Supplemental Prospectus (Form 424B5)

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-296469

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document contains two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also supplements and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part is the accompanying prospectus, which provides more general information, some of which may not apply to this offering. If the information contained or incorporated by reference in this prospectus supplement differs or varies from the information contained in the accompanying prospectus, you should rely on the information set forth in this prospectus supplement.

In this prospectus supplement and the accompanying prospectus, as permitted by law, we "incorporate by reference" information from other documents that we file with the Securities and Exchange Commission (the "SEC"). This means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus supplement and the accompanying prospectus and should be read with the same care. When we update the information contained in documents that have been incorporated by reference by making future filings with the SEC, the information incorporated by reference in this prospectus supplement and the accompanying prospectus is considered to be automatically updated and superseded. In other words, in case of a conflict or inconsistency between information contained in this prospectus supplement and the accompanying prospectus and information incorporated by reference into this prospectus supplement and the accompanying prospectus, you should rely on the information contained in the document that was filed most recently with the SEC.

Neither we nor the underwriters have authorized any other person to provide you with any information other than that contained or incorporated by reference into this prospectus supplement, the accompanying prospectus or any relevant free writing prospectus prepared by or on behalf of us or to which we have referred you. We and the underwriters take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

The information contained in this prospectus supplement and the accompanying prospectus is accurate only as of the date of this prospectus supplement or the date of the accompanying prospectus, as applicable, and the information in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate only as of the date of those respective documents, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or of any sale of our common stock. Our business, financial condition, results of operations and prospects may have changed since those dates. It is important for you to read and consider all information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus in making your investment decision. You should read this prospectus supplement, the accompanying prospectus and any free writing prospectus that we have authorized for use in connection with this offering, as well as the documents incorporated by reference herein and therein and the additional information described under "Where You Can Find More Information" and "Incorporation by Reference" in this prospectus supplement and in the accompanying prospectus, before investing in our common stock.

As used in this prospectus supplement, unless the context otherwise requires, references to "Aeva," "company," "we," "us" and "our" refer to Aeva Technologies, Inc.

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This prospectus supplement, the accompanying prospectus and the information incorporated herein or therein by reference contains market data, industry statistics and other data that have been obtained or compiled from information made available by independent third parties. We have not independently verified the accuracy and completeness of such data.

All trademarks, service marks and trade names appearing in this prospectus supplement are the property of their respective holders. Use or display by us of other parties' trademarks, trade dress, or products in this prospectus supplement is not intended to, and does not, imply a relationship with, or endorsements or sponsorship of, us by the trademark or trade dress owners.

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RISK FACTORS

Investing in our securities is speculative and involves a high degree of risk. Before investing in our securities, you should consider carefully the risks described below, together with the risks described in the section entitled "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2025, which is incorporated by reference in its entirety, as well as the other information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus that we authorize for use in connection with this offering, including our financial statements and the related notes thereto. If any of the following risks occur, our business, financial condition, results of operations and future growth prospects could be materially and adversely affected. In these circumstances, the market price of our common stock could decline, and you may lose all or part of your investment. This prospectus supplement also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in the forward-looking statements as a result of a number of factors, including the risks described below. See "Special Note Regarding Forward-Looking Statements."

Risks Related To This Offering

If you purchase our securities in this offering, you will incur immediate and substantial dilution in the book value of your shares.

Investors purchasing securities in this offering will pay a price per share that substantially exceeds the as adjusted net tangible book value per share of our common stock. As a result, investors purchasing securities in this offering will incur immediate dilution of $     per share (or $     per share if the underwriters exercise their option to purchase additional shares in full), representing the difference between the public offering price of $     and our as adjusted net tangible book value per share as of March 31, 2026. To the extent outstanding options or warrants to purchase shares of our common stock are exercised, or restricted stock units are settled in shares of our common stock, investors in this offering may incur further dilution. For more information on the dilution you may suffer as a result of investing in this offering, see the section of this prospectus supplement entitled "Dilution."

We may allocate the net proceeds from this offering in ways that you and other stockholders may not approve.

Our management will have broad discretion in the application of the net proceeds from this offering, including for any of the purposes described in the section titled "Use of Proceeds." Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. Our management might not apply our net proceeds in ways that ultimately increase the value of your investment, and the failure by our management to apply these funds effectively could harm our business. Pending their use, we may invest the net proceeds from this offering in interest-bearing, investment-grade securities, certificates of deposit or government securities. These investments may not yield a favorable return to our stockholders. If we do not invest or apply the net proceeds from this offering in ways that enhance stockholder value, we may fail to achieve expected results, which could cause our stock price to decline.

If we sell shares of our common stock in future financings, stockholders may experience immediate dilution and, as a result, our stock price may decline.

We may from time to time issue additional shares of common stock at a discount from the current trading price of our common stock. As a result, our stockholders would experience immediate dilution upon the purchase of any shares of our common stock sold at such discount. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preferred stock or common stock. If we issue common stock or securities convertible into common stock, our stockholders would experience additional dilution and, as a result, our stock price may decline.

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Future sales of our common stock, or the perception that such sales may occur, could depress the price of our common stock.

The price of our common stock could decline if there are substantial sales of our common stock, particularly sales by our directors, executive officers and significant stockholders, or if there is a large number of shares of our common stock available for sale and the market perceives that sales will occur. After this offering, we will have      outstanding shares of our common stock, based on the number of shares outstanding as of March 31, 2026 and assuming that the underwriters do not exercise their option to purchase additional shares of common stock. All of the shares of common stock sold in this offering will be available for sale in the public market, unless purchased by our affiliates or existing stockholders who are subject to lock-up restrictions described below.

We, our executive officers and directors have agreed that, among other things and subject to certain exceptions, during the period ending 60 days after the date of this prospectus supplement, we and they will not offer, sell, dispose of or hedge any shares of our common stock, subject to specified limited exceptions, without, in each case, the prior written consent of Morgan Stanley & Co. LLC, who may release any of the securities subject to these lock-up agreements at any time without notice. Shares held by directors, executive officers and other affiliates will be subject to volume limitations under Rule 144 under the Securities Act of 1933, as amended (the "Securities Act"), and various vesting agreements. Sales of a substantial number of such shares upon expiration of the lock-up agreements, the perception that such sales may occur or early release of these agreements, could cause our market price to fall or make it more difficult for you to sell your common stock at a time and price that you deem appropriate.

In addition, we have filed a registration statement registering under the Securities Act the shares of our common stock reserved for issuance under our 2021 Incentive Award Plan, as amended, and our ESPP, including shares issuable upon exercise of outstanding options. These shares can be freely sold in the public market upon issuance, subject to volume limitations applicable to affiliates and the lock-up agreements described above.

We cannot predict the effect that future sales of common stock or other equity-related securities would have on the market price of our common stock.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus, and the information incorporated by reference in this prospectus and any prospectus supplement contain or may contain forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), which statements involve substantial risk and uncertainties. All statements contained in this prospectus supplement or accompanying prospectus and any incorporated by reference herein or therein other than statements of historical fact, including statements regarding our future results of operations and financial position, our business strategy and plans, our objectives for future operations and our anticipated use of proceeds from this offering, are forward-looking statements. The words "believe," "may," "will," "estimate," "continue," "anticipate," "goal," "plan," "intend," "expect," "seek", and similar expressions are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and trends. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including our history of losses, and limited sales; the risk our programs are not fully developed and commercialized, or if such programs experience significant delays; our limited operating history; the risk that our strategic initiatives designed to grow our business, including our selection by a top European passenger original equipment manufacturer and our strategic collaboration with LG Innotek Co., Ltd., may not be successful or may prove more costly than we currently anticipate; the risk our products are not selected for inclusion in development programs for assisted driving systems or autonomous driving systems , industrial automation, consumer device, robotics and security applications, or are not adopted by customers; the lengthy period of time from a design win to implementation, and the risks of cancellation or postponement of the contract or unsuccessful implementation; the risk our forward looking estimates of certain financial metrics, including but not limited to Order Book, may prove inaccurate; the risk that we may be unable to effectively manage our supply chain; the risk that the complexity of our products could result in unforeseen delays or expenses from undetected defects, errors or reliability issues in hardware or software which could reduce the market adoption of new products, damage our reputation with current or prospective customers, expose Aeva to product liability and other claims and adversely affect our operating costs; continued pricing pressures, automotive original equipment manufacturer ("OEM") cost reduction initiatives and the ability of automotive OEMs to re-source or cancel vehicle or technology programs; the risks relating to incurring substantial R&D costs and devoting significant resources to identifying and commercializing new products; uncertainty related to the market adoption of LiDAR, including Aeva's 4D LiDAR technology; the risk our transition to an outsourced manufacturing business model may not be successful; risks related to product liability or warranty claims that could result in significant direct or indirect costs to us; the risk of our high dependence on the services of Soroush Salehian Dardashti and Mina Rezk, our two founders; the potential interruption or failure of our information technology and communication systems and cybersecurity risks to our operational systems, security systems, infrastructure, integrated software in our LiDAR solutions and those risks described under "Risk Factors" of this prospectus supplement, the accompanying prospectus, and in our Annual Report on Form 10-K for the year ended December 31, 2026 as well as any periodic report incorporated by reference in this prospectus supplement or the accompanying prospectus. Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties and assumptions, the future events and trends discussed in this prospectus may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements.

You should not rely upon forward-looking statements as predictions of future events. The forward-looking statements contained in this prospectus, any prospectus supplement, the information incorporated by reference in this prospectus or any prospectus supplement, or any free writing prospectus we may authorize are based on information currently available to us and expectations and assumptions that we deem reasonable at the time the statements were made. We do not undertake any obligation to update any forward-looking statements in this prospectus, any prospectus supplement, including the information incorporated by reference in this prospectus or

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any prospectus supplement, any free writing prospectus we may authorize or in any of our other communications, except as required by law. Such forward-looking statements are subject to risks, uncertainties (some of which are beyond our control) and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements. All such forward-looking statements should be read as of the time the statements were made and with the recognition that these forward-looking statements may not be complete or accurate at a later date.

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USE OF PROCEEDS

We estimate that net proceeds from this offering will be approximately $    million, or approximately $    million if the underwriters exercise their option to purchase additional shares in full, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We currently intend to use the net proceeds from this offering for general corporate purposes including to meet the accelerating commercial interest in AI infrastructure and Co-Packaged Optics (CPO) in addition to the growing demand for existing applications.

Pending our use of the net proceeds from this offering, we plan to invest the net proceeds in interest-bearing, investment-grade securities, certificates of deposit or government securities.

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DIVIDEND POLICY

We have never declared or paid cash dividends on our common stock. We currently intend to retain all available funds and any future earnings for use in the operation of our business and do not anticipate paying any cash dividends on our common stock in the foreseeable future. Any decision to declare and pay dividends as a public company in the future will be made at the discretion of our board of directors and will depend on, among other things, our results of operations, financial condition, cash requirements, contractual restrictions and other factors that our board of directors may deem relevant. In addition, our ability to pay dividends may be limited by covenants of any existing and future outstanding indebtedness we or our subsidiaries incur.

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CAPITALIZATION

The following table sets forth our cash and cash equivalents and capitalization as of March 31, 2026:

You should read this table in conjunction with the sections titled "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our financial statements and related notes appearing in our Annual Report on Form 10-K for the year ended December 31, 2205 and our Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, which are incorporated by reference in this prospectus supplement and the accompanying prospectus.

The number of shares of our common stock issued and outstanding as of March 31, 2026 as reported in the table above excludes:

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DILUTION

If you invest in our common stock in this offering, your ownership interest will be immediately diluted to the extent of the difference between the public offering price per share of our common stock and the as adjusted net tangible book value per share of our common stock immediately after the completion of this offering.

Historical net tangible book value per share represents our total tangible assets less our liabilities and preferred stock that is not included in equity divided by the total number of shares of common stock outstanding. As of March 31, 2026, our historical net tangible book value was approximately $(13.0) million, or $(0.21) per share of common stock, based on 62,984,603 shares of common stock outstanding as of March 31, 2026.

After giving effect to our sale in this offering of     shares of common stock at the public offering price of $     per share, and after deducting estimated underwriting discounts and commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of March 31, 2026 would have been approximately $     million, or $     per share of our common stock. This amount represents an immediate increase in as adjusted net tangible book value of $     per share to our existing stockholders and an immediate dilution of $     per share to investors participating in this offering. Net tangible book value dilution per share to new investors participating in this offering represents the difference between the amount per share paid by purchaser of common stock in this offering and the as adjusted net tangible book value per share of common stock immediately after completion of this offering.

Dilution per share to new investors purchasing our common stock is determined by subtracting as adjusted net tangible book value per share after this offering from the public offering price per share paid by new investors. The following table illustrates this dilution to new investors on a per share basis (without giving effect to any exercise by the underwriters of their option to purchase additional shares):

If the underwriters' option to purchase additional shares in this offering is exercised in full, the as adjusted net tangible book value would be $      per share, the increase in the net tangible book value per share for existing stockholders would be $     per share and the dilution to new investors participating in this offering would be $     per share.

The foregoing tables and calculations (other than the historical net tangible book value calculation) are based on 62,984,603 shares of our common stock outstanding as of March 31, 2026, and unless otherwise indicated, excludes:

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To the extent that outstanding warrants, stock options or RSUs are exercised or settled, as the case may be, you may experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital by issuing equity or convertible debt securities, your ownership will be further diluted.

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES FOR NON-U.S. HOLDERS OF OUR COMMON STOCK

The following is a general discussion of the material U.S. federal income tax consequences applicable to non-U.S. holders (as defined below) with respect to their ownership and disposition of shares of our common stock issued pursuant to this offering. For purposes of this discussion, a non-U.S. holder means a beneficial owner of our common stock (other than an entity or arrangement that is treated as a partnership for U.S. federal income tax purposes) that is not, for U.S. federal income tax purposes, any of the following:

This discussion is based on current provisions of the Internal Revenue Code of 1986, as amended (the "Code"), existing, temporary and proposed Treasury Regulations promulgated thereunder, published administrative pronouncements of the Internal Revenue Service or, the IRS, and other applicable authorities, all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any such change or differing interpretation could alter the tax consequences described in this discussion. There can be no assurance that the IRS will not challenge one or more of the tax consequences described herein, and we have not obtained, nor do we intend to obtain, a ruling with respect to the U.S. federal income tax consequences to a holder of the ownership or disposition of our common stock.

This discussion assumes that a non-U.S. holder holds shares of our common stock as a capital asset (generally, property held for investment) for U.S. federal income tax purposes. This discussion does not address all aspects of U.S. federal income taxation that may be important to a particular non-U.S. holder in light of that non-U.S. holder's individual circumstances, nor does it address any aspects of the unearned income Medicare contribution tax pursuant to the Health Care and Education Reconciliation Act of 2010, the special tax accounting rules under Section 451(b) of the Code, any U.S. gift or estate taxes, any U.S. alternative minimum taxes or any state, local or non-U.S. taxes. This discussion may not apply, in whole or in part, to particular non-U.S. holders in light of their individual circumstances or to holders subject to special treatment under the U.S. federal income tax laws (such as insurance companies, tax-exempt organizations, financial institutions, brokers or dealers in securities, "controlled foreign corporations," "passive foreign investment companies," non-U.S. holders that hold our common stock as part of a straddle, hedge, conversion transaction or other integrated investment, and certain U.S. expatriates). If a partnership (or other entity or arrangement treated as a partnership for U.S. federal income tax purposes) holds our common stock, the tax treatment of a partner therein will generally depend on the status of the partner and the activities of the partnership. Partners of a partnership holding our common stock should consult their tax advisor as to the particular U.S. federal income tax consequences applicable to them of the purchase, ownership and disposition of our common stock.

INVESTORS CONSIDERING THE PURCHASE OF OUR COMMON STOCK SHOULD CONSULT THEIR OWN TAX ADVISORS REGARDING THE APPLICATION OF THE U.S. FEDERAL INCOME AND ESTATE TAX LAWS TO THEIR PARTICULAR SITUATIONS AND THE CONSEQUENCES OF NON-U.S., STATE, OR LOCAL LAWS AND TAX TREATIES.

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Dividends

We do not expect to declare or make any distributions on our common stock in the foreseeable future. If we do pay dividends on shares of our common stock, however, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Distributions in excess of our current and accumulated earnings and profits will constitute a return of capital that is applied against and reduces, but not below zero, a non-U.S. holder's adjusted tax basis in shares of our common stock. Any amount distributed in excess of basis will be treated as capital gain and will be subject to the treatment described below under "-Gain on Sale or Other Disposition of Common Stock." Any distributions will also be subject to the discussion below under "-Backup Withholding and Information Reporting" and "-Foreign Account Tax Compliance Act."

Any dividend paid to a non-U.S. holder on our common stock that is not effectively connected with a non-U.S. holder's conduct of a trade or business in the United States will generally be subject to U.S. withholding tax at a 30% rate. The withholding tax might apply at a reduced rate, however, under the terms of an applicable income tax treaty between the United States and the non-U.S. holder's country of residence. Non-U.S. holders should consult their own tax advisors regarding their entitlement to benefits under a relevant income tax treaty. Generally, in order for us or our paying agent to withhold tax at a lower treaty rate, a non-U.S. holder must certify its entitlement to treaty benefits. A non-U.S. holder generally can meet this certification requirement by providing an IRS Form W-8BEN, W-8BEN-E or other appropriate IRS Form W-8 (or any successor or substitute form thereof) to us or our paying agent. If the non-U.S. holder holds the stock through a financial institution or other agent acting on the holder's behalf, the holder will be required to provide appropriate documentation to the holder's agent. The holder's agent will then be required to provide certification to us or our paying agent, either directly or through other intermediaries. Any such certifications provided to an applicable withholding agent or intermediary must be updated periodically. If a non-U.S. holder is eligible for a reduced rate of U.S. federal withholding tax under an income tax treaty, such non-U.S. holder may generally obtain a refund or credit of any excess amounts withheld by filing an appropriate claim for a refund with the IRS in a timely manner.

Dividends received by a non-U.S. holder that are effectively connected with a U.S. trade or business conducted by the non-U.S. holder, and if required by an applicable income tax treaty between the United States and the non-U.S. holder's country of residence, are attributable to a permanent establishment of fixed base maintained by the non-U.S. holder in the United States, are not subject to U.S. withholding tax. To obtain this exemption, a non-U.S. holder must provide us or our paying agent with an IRS Form W-8ECI (or any successor or substitute form thereof) properly certifying that such dividends are effectively connected with the non-U.S. holder's conduct of a trade or business within the United States. Such effectively connected dividends, although not subject to withholding tax, are taxed at the same U.S. federal income tax rates applicable to U.S. persons, net of certain deductions and credits. In addition, dividends received by a corporate non-U.S. holder that are effectively connected with a U.S. trade or business of the corporate non-U.S. holder may also be subject to a branch profits tax at a rate of 30% or such lower rate as may be specified by an applicable tax treaty.

Gain on Sale or Other Disposition of Common Stock

Subject to the discussions below under "-Backup Withholding and Information Reporting" and "-Foreign Account Tax Compliance Act," non-U.S. holders will generally not be subject to U.S. federal income tax on any gains realized on the sale, exchange or other disposition of our common stock unless:

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The FIRPTA rules may apply to a sale, exchange or other disposition of our common stock if we are, or were within the shorter of the five-year period preceding the disposition and the non-U.S. holder's holding period, a "U.S. real property holding corporation," or USRPHC. In general, we would be a USRPHC if interests in U.S. real property comprised at least half of the value of our business assets. We do not believe that we are a USRPHC and we do not anticipate becoming one in the future. Even if we are or were to become a USRPHC, gain arising from the sale or other taxable disposition by a non-U.S. holder will not be subject to U.S. federal income tax if our common stock is "regularly traded," as defined by applicable Treasury Regulations, on an established securities market, and such non-U.S. holder owned, actually and constructively, 5% or less of our common stock throughout the shorter of the five-year period ending on the date of the sale or other taxable disposition and the non-U.S. holder's holding period.

If any gain from the sale, exchange or other disposition of our common stock, (i) is effectively connected with a U.S. trade or business conducted by a non-U.S. holder and (ii) if required by an applicable income tax treaty between the United States and the non-U.S. holder's country of residence, is attributable to a permanent establishment or fixed base maintained by such non-U.S. holder in the United States, then the gain generally will be subject to U.S. federal income tax at the same rates applicable to U.S. persons, net of certain deductions and credits. If the non-U.S. holder is a corporation, under certain circumstances, that portion of its earnings and profits that is effectively connected with its U.S. trade or business, subject to certain adjustments, generally would be subject also to a "branch profits tax" at a rate of 30% or such lower rate as may be specified by an applicable income tax treaty.

Backup Withholding and Information Reporting

We must report annually to the IRS and to each non-U.S. holder the amount of distributions paid to, and the tax withheld with respect to, each non-U.S. holder. These reporting requirements apply regardless of whether withholding was reduced or eliminated by an applicable tax treaty. Copies of this information reporting may also be made available under the provisions of a specific tax treaty or agreement with the tax authorities in the country in which the non-U.S. holder resides or is established.

A non-U.S. holder will generally be subject to backup withholding on distributions on our common stock paid to such holder unless such holder certifies under penalties of perjury that, among other things, it is a non-U.S. holder, generally by providing an applicable and properly completed IRS Form W-8BEN, IRS Form W-8BEN-E, or IRS Form W-8ECI (and the payer does not have actual knowledge or reason to know that such holder is a U.S. person) or otherwise establishes an exemption.

Information reporting and backup withholding generally are not required with respect to the amount of any proceeds from the sale or other disposition of our common stock by a non-U.S. holder outside the United States through a foreign office of a foreign broker that does not have certain specified connections to the United States. However, if a non-U.S. holder sells or otherwise disposes of its shares of common stock through a U.S. broker or the U.S. offices of a foreign broker, the broker will generally be required to report the amount of proceeds paid to the non-U.S. holder to the IRS and impose backup withholding on that amount unless such non-U.S. holder provides appropriate certification to the broker of its status as a non-U.S. holder (and the payer does not have actual knowledge or reason to know that such holder is a U.S. person) or otherwise establishes an exemption.

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Backup withholding is not an additional income tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder generally can be credited against the non-U.S. holder's U.S. federal income tax liability, if any, or refunded, provided that the required information is furnished to the IRS in a timely manner. Non-U.S. holders should consult their tax advisors regarding the application of the information reporting and backup withholding rules to them.

Foreign Account Tax Compliance Act

Under the Foreign Account Tax Compliance Act ("FATCA"), withholding tax of 30% applies to certain payments to foreign financial institutions, including investment funds, and certain other non-U.S. persons that fail to comply with certain information reporting and certification requirements pertaining to their direct and indirect U.S. securityholders and/or U.S. accountholders and do not otherwise qualify for an exemption. Under applicable Treasury Regulations and IRS guidance, this withholding currently applies to payments of dividends, if any, on, and, subject to the proposed Treasury Regulations discussed below, gross proceeds from the sale or other disposition of, our common stock. An intergovernmental agreement between the United States and a foreign country may modify the requirements described in this paragraph.

While, beginning on January 1, 2019, withholding under FATCA would have applied also to payments of gross proceeds from the sale or other disposition of our common stock, proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued.

Prospective investors are encouraged to consult with their own tax advisors regarding the possible implications of FATCA on their investment in our common stock.

PROSPECTIVE INVESTORS SHOULD CONSULT THEIR OWN TAX ADVISORS REGARDING THE POTENTIAL APPLICATION OF WITHHOLDING UNDER FATCA TO THEIR INVESTMENT IN OUR COMMON STOCK. THE PRECEDING DISCUSSION OF U.S. FEDERAL INCOME TAX CONSEQUENCES IS FOR GENERAL INFORMATION PURPOSES ONLY. IT IS NOT TAX ADVICE. EACH PROSPECTIVE INVESTOR SHOULD CONSULT ITS OWN TAX ADVISOR REGARDING THE PARTICULAR U.S. FEDERAL, STATE, LOCAL, AND NON-U.S. TAX CONSEQUENCES OF PURCHASING, HOLDING, AND DISPOSING OF OUR COMMON STOCK, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAWS.

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UNDERWRITING

Under the terms and subject to the conditions in an underwriting agreement dated the date of this prospectus supplement, the underwriters named below, for whom Morgan Stanley & Co. LLC is acting as representative, have severally agreed to purchase, and we have agreed to sell to them, severally, the number of shares indicated below:

The underwriters and the representative are collectively referred to as the "underwriters" and the "representative," respectively. The underwriters are offering the shares of common stock subject to their acceptance of the shares from us and subject to prior sale. The underwriting agreement provides that the obligations of the several underwriters to pay for and accept delivery of the shares of common stock offered by this prospectus supplement are subject to the approval of certain legal matters by their counsel and to certain other conditions. The underwriters are obligated to take and pay for all of the shares of common stock offered by this prospectus supplement if any such shares are taken. However, the underwriters are not required to take or pay for the shares covered by the underwriters' option to purchase additional shares described below.

The underwriters initially propose to offer part of the shares of common stock directly to the public at the offering price listed on the cover page of this prospectus supplement and part to certain dealers at a price that represents a concession not in excess of $    per share under the public offering price. After the initial offering of the shares of common stock, the offering price and other selling terms may from time to time be varied by the representative.

We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to     additional shares of common stock at the public offering price listed on the cover page of this prospectus supplement, less underwriting discounts and commissions. To the extent the option is exercised, each underwriter will become obligated, subject to certain conditions, to purchase about the same percentage of the additional shares of common stock as the number listed next to the underwriter's name in the preceding table bears to the total number of shares of common stock listed next to the names of all underwriters in the preceding table.

The following table shows the per share and total public offering price, underwriting discounts and commissions, and proceeds before expenses to us. These amounts are shown assuming both no exercise and full exercise of the underwriters' option to purchase up to an additional      shares of common stock.

The estimated offering expenses payable by us, exclusive of the underwriting discounts and commissions, are approximately $   . We have agreed to reimburse the underwriters for all expenses relating to clearance of this offering with the Financial Industry Regulatory Authority.

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Our common stock is listed on the NASDAQ Global Select Market under the trading symbol "AEVA".

We have agreed that, without the prior written consent of Morgan Stanley & Co. LLC on behalf of the underwriters, we will not, and will not publicly disclose an intention to, during the period ending 60 days after the date of this prospectus supplement (the "restricted period"), (a) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for shares of common stock or (b) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the common stock, whether any such transaction is to be settled by delivery of common stock or such other securities, in cash or otherwise, or (c) file any registration statement with the Securities and Exchange Commission relating to the offering of any shares of common stock or any securities convertible into or exercisable or exchangeable for common stock.

The restrictions described in the immediately preceding paragraph to do not apply to:

Our directors and officers (each, a "lock-up party" and together, the "lock-up parties") have agreed that, without the prior written consent of Morgan Stanley & Co. LLC on behalf of the underwriters, they will not, and will not publicly disclose an intention to, during the restricted period, (a) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for shares of common stock or (b) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the common stock, whether any such transaction is to be settled by delivery of common stock or such other securities, in cash or otherwise. The lock-up parties acknowledge and agree that they are precluded from engaging in any hedging or other transaction designed or intended, or which could reasonably be expected to lead to or result in, a sale or disposition of any shares of common stock, or any securities convertible into or exercisable or exchangeable for common stock, even if any such sale or disposition transaction or transactions would be made or executed by or on behalf of someone other than the lock-up parties.

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The restrictions described in the immediately preceding paragraph do not apply to (a) transactions relating to shares of common stock or other securities acquired in open market transactions after the completion of this offering; (b) transfers of shares of common stock or any security convertible into common stock (1) as a bona fide gift or charitable contribution or (2) for bona fide estate planning purposes, in each case, in a transfer not involving a disposition for value; (c) transfers or dispositions of shares of common stock or any security convertible into or exercisable for common stock to any member of the immediate family of the lock-up party or any trust for the direct or indirect benefit of the lock-up party or the immediate family of the lock-up party, or if the lock-up party is a trust, to a trustor, trustee or any beneficiary (including such trustor, trustee or beneficiary's estate) in a transaction not involving a disposition for value; (d) distributions, transfers or dispositions of shares of common stock or any security convertible into or exercisable for common stock to any corporation, partnership, limited liability company, other entity that is an affiliate of the lock-up party or of which all of the beneficial ownership interests of which are held by the lock-up party or the immediate family of the lock-up party in a transaction not involving a disposition for value; (e) transfers or dispositions of shares of common stock or any security convertible into or exercisable for common stock (1) by will, other testamentary document or intestate succession and (2) by operation of law including, without limitation, pursuant to orders of a court or regulatory agency, in connection with a negotiated divorce settlement, pursuant to a qualified domestic relations order or by other court order; (f) to a nominee or custodian of a person or entity to whom a disposition or transfer would be permissible under the clauses above; (g) distributions, transfers or dispositions of shares of common stock or any security convertible into or exercisable for common stock to limited partners or stockholders of the lock-up party; (h)(1) to us in connection with the vesting, settlement, or exercise of restricted stock units, options, warrants or other rights to purchase shares of common stock (including, in each case, by way of "net" or "cashless" exercise), including for the payment of exercise price and tax and remittance payments due as a result of the vesting, settlement, or exercise of such restricted stock units, options, warrants or rights, provided that any such shares of common stock received upon such exercise, vesting or settlement shall be subject to the foregoing restrictions, and provided further that any such restricted stock units, options, warrants or rights are held by the lock-up party pursuant to an agreement or equity awards granted under a stock incentive plan or other equity award plan, each such agreement or plan which is described herein or (2) as a part of sales of stock that we elected to automatically have sold through an approved broker as necessary to satisfy tax withholding requirements upon the vesting of any restricted stock or restricted stock units; (i) pursuant to a bona fide third-party tender offer, merger, consolidation or other similar transaction, that is approved by our board of directors, made to all holders of our capital stock involving a change of control; provided, that, in the event that such tender offer, merger, consolidation or other similar transaction is not completed, the shares of common stock or any securities convertible into or exercisable for common stock beneficially owned by the lock-up party shall remain subject to the foregoing restrictions; (j) transfers or sales of common stock pursuant to any Rule 10b5-1 Plan that has been entered into by a lock-up party prior to the date of this prospectus supplement, provided that any filing required to be made under Section 16(a) of the Exchange Act as a result of such transfer or sale shall state that such transfer or sale is pursuant to a trading plan pursuant to Rule 10b5-1; (k) the establishment of a trading plan on behalf of a shareholder, officer or director pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of common stock, provided that (1) such plan does not provide for the transfer of common stock during the restricted period and (2) the extent a public announcement or filing under the Exchange Act, if any, is required of or voluntarily made by or on behalf of a lock-up party or us regarding the establishment of such plan, such announcement or filing shall include a statement to the effect that no transfer of common stock may be made under such plan during the restricted period. Notwithstanding the foregoing, in the case of any transfer or distribution pursuant to clause (b) through (g), each transferee, donee or distributee will be subject to the foregoing restrictions, and provided further that in the case of any transfer or distribution pursuant to clause (c) through (g), no filings under Section 16(a) of the Exchange Act shall be required or voluntarily made.

Morgan Stanley & Co. LLC, in its sole discretion, may release the common stock and other securities subject to the lock-up agreements described above in whole or in part at any time.

In order to facilitate the offering of the common stock, the underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the common stock. Specifically, the underwriters may sell

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more shares than they are obligated to purchase under the underwriting agreement, creating a short position. A short sale is covered if the short position is no greater than the number of shares available for purchase by the underwriters under the option. The underwriters can close out a covered short sale by exercising the option or purchasing shares in the open market. In determining the source of shares to close out a covered short sale, the underwriters will consider, among other things, the open market price of shares compared to the price available under the option. The underwriters may also sell shares in excess of the option, creating a naked short position. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the common stock in the open market after pricing that could adversely affect investors who purchase in this offering. As an additional means of facilitating this offering, the underwriters may bid for, and purchase, shares of common stock in the open market to stabilize the price of the common stock. These activities may raise or maintain the market price of the common stock above independent market levels or prevent or retard a decline in the market price of the common stock. The underwriters are not required to engage in these activities and may end any of these activities at any time.

We and the underwriters have agreed to indemnify each other against certain liabilities, including liabilities under the Securities Act.

A prospectus supplement in electronic format may be made available on websites maintained by one or more underwriters, or selling group members, if any, participating in this offering. The representative may agree to allocate a number of shares of common stock to underwriters for sale to their online brokerage account holders. Internet distributions will be allocated by the representative to underwriters that may make Internet distributions on the same basis as other allocations.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. Certain of the underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for us, for which they received or will receive customary fees and expenses.

In addition, in the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities and instruments. Such investment and securities activities may involve our securities and instruments. The underwriters and their respective affiliates may also make investment recommendations or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long or short positions in such securities and instruments.

Selling Restrictions

Notice to Prospective Investors in the European Economic Area

In relation to each Member State of the European Economic Area (each, a "Relevant State") no shares of common stock have been offered or will be offered pursuant to the offering to the public in that Relevant State prior to the publication of a prospectus in relation to the shares of common stock which has been approved by the competent authority in that Relevant State or, where appropriate, approved in another Relevant State and notified to the competent authority in that Relevant State, all in accordance with the Prospectus Regulation, except that the shares of common stock may be offered to the public in that Relevant State at any time:

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provided that no such offer of the shares of common stock shall require us or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation. Each person who initially acquires any shares of common stock or to whom any offer is made will be deemed to have represented, acknowledged and agreed to and with each of the underwriters and us that it is a "qualified investor" within the meaning of Article 2(e) of the Prospectus Regulation. In the case of any shares of common stock being offered to a financial intermediary as that term is used in the Prospectus Regulation, each such financial intermediary will be deemed to have represented, acknowledged and agreed that the shares of common stock acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares of common stock to the public other than their offer or resale in a Relevant State to qualified investors as so defined or in circumstances in which the prior consent of the underwriters have been obtained to each such proposed offer or resale.

For the purposes of this provision, the expression an "offer to the public" in relation to the shares of common stock in any Relevant State means the communication in any form and by any means of sufficient information on the terms of the offer and any shares of common stock to be offered so as to enable an investor to decide to purchase or subscribe for any shares of common stock, and the expression "Prospectus Regulation" means Regulation (EU) 2017/1129.

Notice to Prospective Investors in the United Kingdom

No shares of common stock have been offered or will be offered pursuant to the offering to the public in the United Kingdom, except that the shares of common stock may be offered to the public in the United Kingdom at any time:

For the purposes of this provision, the expression an "offer to the public" in relation to the shares of common stock in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offer and any shares of common stock to be offered so as to enable an investor to decide to buy or subscribe for any shares of common stock and the expression "POATRs" means the Public Offers and Admissions to Trading Regulations 2024.

In addition, in the United Kingdom, this document is being distributed only to, and is directed only at, and any offer subsequently made may only be directed at persons who are "qualified investors" (as defined in the Prospectus Regulation) (i) who have professional experience in matters relating to investments falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Order") and/or (ii) who are high net worth companies (or persons to whom it may otherwise be lawfully communicated) falling within Article 49(2)(a) to (d) of the Order (all such persons together being referred to as

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"relevant persons") or otherwise in circumstances which have not resulted and will not result in an offer to the public of the shares of common stock in the United Kingdom within the meaning of the POATRs. Any person in the United Kingdom that is not a relevant person should not act or rely on the information included in this document or use it as basis for taking any action. In the United Kingdom, any investment or investment activity that this document relates to may be made or taken exclusively by relevant persons.

Notice to Prospective Investors in Canada

The shares of common stock may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares of common stock must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser's province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser's province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 (or, in the case of securities issued or guaranteed by the government of a non-Canadian jurisdiction, section 3A.4) of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Notice to Prospective Investors in Switzerland

This prospectus does not constitute an offer to the public or a solicitation to purchase or invest in any shares of common stock. No shares of common stock have been offered or will be offered to the public in Switzerland, except that offers of shares of common stock may be made to the public in Switzerland at any time under the following exemptions under the Swiss Financial Services Act (the "FinSA"):

provided that no such offer of shares of common stock shall require us or any investment bank to publish a prospectus pursuant to Article 35 FinSA.

The shares of common stock have not been and will not be listed or admitted to trading on a trading venue in Switzerland.

Neither this document nor any other offering or marketing material relating to the shares of common stock constitutes a prospectus as such term is understood pursuant to the FinSA and neither this document nor any other offering or marketing material relating to the shares of common stock may be publicly distributed or otherwise made publicly available in Switzerland.

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Notice to Prospective Investors in Australia

This prospectus:

The shares of common stock may not be directly or indirectly offered for subscription or purchased or sold, and no invitations to subscribe for or buy the shares of common stock may be issued, and no draft or definitive offering memorandum, advertisement or other offering material relating to any shares of common stock may be distributed in Australia, except where disclosure to investors is not required under Chapter 6D of the Corporations Act or is otherwise in compliance with all applicable Australian laws and regulations. By submitting an application for the shares of common stock, you represent and warrant to us that you are an Exempt Investor.

As any offer of shares of common stock under this prospectus will be made without disclosure in Australia under Chapter 6D.2 of the Corporations Act, the offer of those securities for resale in Australia within 12 months may, under section 707 of the Corporations Act, require disclosure to investors under Chapter 6D.2 if none of the exemptions in section 708 applies to that resale. By applying for the shares of common stock you undertake to us that you will not, for a period of 12 months from the date of issue of the shares of common stock, offer, transfer, assign or otherwise alienate those shares of common stock to investors in Australia except in circumstances where disclosure to investors is not required under Chapter 6D.2 of the Corporations Act or where a compliant disclosure document is prepared and lodged with ASIC.

Notice to Prospective Investors in Japan

The shares of common stock have not been and will not be registered pursuant to Article 4, Paragraph 1 of the Financial Instruments and Exchange Act (the "FIEA"). Accordingly, none of the shares of common stock nor any interest therein may be offered or sold, directly or indirectly, in Japan or to, or for the benefit of, any "resident" of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to or for the benefit of a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIEA and any other applicable laws, regulations and ministerial guidelines of Japan in effect at the relevant time.

Notice to Prospective Investors in Singapore

This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares of common stock may not be circulated or distributed, nor may the shares of common stock be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than:

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Singapore SFA Product Classification-In connection with Section 309B of the SFA and the CMP Regulations 2018, unless otherwise specified before an offer of shares of common stock, we have determined, and hereby notify all relevant persons (as defined in Section 309A(1) of the SFA), that the shares of common stock are "prescribed capital markets products" (as defined in the CMP Regulations 2018) and Excluded Investment Products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

Notice to Prospective Investors in the Dubai International Financial Centre

This prospectus relates to an Exempt Offer in accordance with the Markets Rules 2012 of the Dubai Financial Services Authority (the "DFSA"). This prospectus is intended for distribution only to persons of a type specified in the Markets Rules 2012 of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for this prospectus. The securities to which this prospectus relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the securities offered should conduct their own due diligence on the securities. If you do not understand the contents of this prospectus you should consult an authorized financial advisor.

In relation to its use in the Dubai International Financial Centre (the "DIFC") this prospectus is strictly private and confidential and is being distributed to a limited number of investors and must not be provided to any person other than the original recipient, and may not be reproduced or used for any other purpose. The interests in the securities may not be offered or sold directly or indirectly to the public in the DIFC.

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Notice to Prospective Investors in Israel

This prospectus does not constitute a prospectus under the Israeli Securities Law, 5728-1968 (the "Israeli Securities Law") and has not been filed with or approved by the Israel Securities Authority. In Israel, this prospectus is being distributed only to, and is directed only at, and any offer of the shares of common stock is directed only at, (i) a limited number of persons in accordance with the Israeli Securities Law and (ii) investors listed in the first addendum (the "Addendum") to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and "qualified individuals," each as defined in the Addendum (as it may be amended from time to time), or, collectively referred to as qualified investors (in each case, purchasing for their own account or, where permitted under the Addendum, for the accounts of their clients who are investors listed in the Addendum). Qualified investors are required to submit written confirmation that they fall within the scope of the Addendum, are aware of the meaning of same and agree to it.

Notice to Prospective Investors in Hong Kong

The shares of common stock have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) (the "SFO") of Hong Kong and any rules made thereunder; or (b) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) (the "CO") of Hong Kong or which do not constitute an offer to the public within the meaning of the CO. No advertisement, invitation or document relating to the securities has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to securities which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" as defined in the SFO and any rules made thereunder.

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LEGAL MATTERS

The validity of the shares of our common stock offered in this prospectus supplement will be passed upon for us by Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP, Redwood City, California. Davis Polk & Wardwell LLP, New York, New York, is acting as counsel for the underwriters in connection with this offering.

EXPERTS

The consolidated financial statements incorporated in this prospectus by reference have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such financial statements are incorporated in reliance upon the report of such firm given their authority as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at https://www.aeva.com. Information accessible on or through our website is not incorporated herein or a part of this prospectus.

We have filed with the SEC a registration statement under the Securities Act relating to the offering of these securities. The registration statement, including the attached exhibits, contains additional relevant information about us and the securities. This prospectus supplement and the accompanying prospectus do not contain all of the information set forth in the registration statement. The registration statement and the documents referred to below under "Incorporation by Reference" are also available on our website, https://www.aeva.com. This website address, and the website addresses included in any documents incorporated by reference herein, are not intended to function as hyperlinks, and the information contained on such websites and on the SEC's website is not incorporated by reference in this prospectus supplement and the accompanying prospectus and you should not consider it a part of this prospectus supplement or the accompanying prospectus.

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INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference into this prospectus supplement certain information we file with it, which means that we can disclose important information by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede information contained in this prospectus supplement. We incorporate by reference the documents listed below that we have previously filed with the SEC (excluding any portions of any Form 8-K that are not deemed "filed" pursuant to the General Instructions of Form 8-K):

We also incorporate by reference into this prospectus supplement additional documents that we may file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus supplement and prior to the completion or termination of the offering, but excluding any information deemed furnished and not filed with the SEC. Any statements contained in a previously filed document incorporated by reference into this prospectus supplement is deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement, or in a subsequently filed document also incorporated by reference herein, modifies or supersedes that statement.

This prospectus supplement may contain information that updates, modifies or is contrary to information in one or more of the documents incorporated by reference in this prospectus supplement.

We have not, and the underwriters have not, authorized anyone to provide you with information, or to make any representation, different from that contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, along with the information contained in any free writing prospectus that we have authorized for use in connection with this offering. We and the underwriters take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. You should not assume that the information in this prospectus supplement is accurate as of any date other than the date of this prospectus supplement or the date of the documents incorporated by reference in this prospectus supplement.

We will provide to each person, including any beneficial owner, to whom this prospectus supplement is delivered, upon written or oral request, at no cost to the requester, a copy of any and all of the information that is incorporated by reference in this prospectus supplement. You should direct any requests for documents to:

Aeva Technologies, Inc.

555 Ellis Street

Mountain View, CA 94043

(650) 481-7070

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PROSPECTUS

Common Stock

Preferred Stock

Debt Securities

Warrants

Up to 3,509,719 shares of common stock offered by the selling stockholder

Shares of common stock offered by additional selling stockholders

We may offer and sell from time to time, in one or more offerings, in amounts, at prices and on terms determined at the time of any such offering, (1) shares of our common stock, (2) shares of our preferred stock, which we may issue in one or more series, (3) debt securities, which may be senior debt securities or subordinated debt securities, or (4) warrants to purchase our common stock.

In addition, this prospectus relates to the offer and potential resale from time to time of (1) up to 3,509,719 shares of our common stock (the "resale shares") held by a selling stockholder (together with its permitted transferees, the "selling stockholder") in amounts, at prices, and on terms that will be determined at the time of the applicable offering and (2) shares of our common stock held by selling stockholders to be named later (the "additional selling stockholders"). The selling stockholder acquired the resale shares from us pursuant to a subscription agreement dated May 13, 2025. We issued the resale shares to the selling stockholder in reliance upon the exemption from registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the "Securities Act"). Our registration of the shares offered by the selling stockholder or any additional selling stockholder does not mean that such selling stockholder or additional selling stockholder will offer or sell any shares of our common stock. We will not receive any of the proceeds from the sale of our common stock by the selling stockholder or any additional selling stockholder. The selling stockholder and any additional selling stockholder will bear all discounts, concessions, commissions and stock transfer taxes, if any, attributable to its sales of shares of our common stock.

Each time we or any additional selling stockholders sell shares of our common stock, we or such additional selling stockholders will provide the specific terms of the offering, and, if applicable, the additional selling stockholders, in a supplement to this prospectus. This prospectus provides you with a general description of the securities we may offer. The securities may be offered by us at prices and on terms determined at the time of offering. We may also authorize one or more free writing prospectuses to be provided to you in connection with such offerings. The prospectus supplement and any related free writing prospectus may add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as the documents incorporated by reference herein and therein, before you invest in the securities described in this prospectus.

We, the selling stockholder or any additional selling stockholder may offer and sell the securities described in this prospectus and any prospectus supplement separately or together sale through underwriters, dealers or agents, or directly to purchasers, or through a combination of these methods. See "Plan of Distribution" beginning on page 8 of this prospectus. If any underwriters, dealers or agents are involved in the sale of these securities we will set forth their names and describe their compensation in the applicable prospectus supplement.

Our common stock, $0.0001 par value per share, is listed on The Nasdaq Global Select Market ("Nasdaq") under the symbol "AEVA." On June 2, 2026, the closing price of our common stock was $27.76 per share.

Investing in our securities involves risks. See the section of this prospectus captioned "Risk Factors" beginning on page 5, as well as in any applicable prospectus supplement and in our Securities and Exchange Commission ("SEC") filings that are incorporated by reference herein.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

The date of this prospectus is June 3, 2026

TABLE OF CONTENTS

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any prospectus supplement, and the information incorporated by reference in this prospectus and any prospectus supplement contain or may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), which statements involve substantial risk and uncertainties. All statements contained in this prospectus other than statements of historical fact, including statements regarding our future results of operations and financial position, our business strategy and plans, and our objectives for future operations, are forward-looking statements. The words "believe," "may," "will," "estimate," "continue," "anticipate," "goal," "plan," "intend," "expect," "seek", and similar expressions are intended to identify forward-looking statements. We have based these forward-looking statements largely on our current expectations and projections about future events and trends. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including our history of losses, and limited sales; the risk our programs are not fully developed and commercialized, or if such programs experience significant delays; our limited operating history; the risk that our strategic initiatives designed to grow our business, including our selection by a top European passenger original equipment manufacturer and our strategic collaboration with LG Innotek Co., Ltd., may not be successful or may prove more costly than we currently anticipate; the risk our products are not selected for inclusion in development programs for assisted driving systems or autonomous driving systems , industrial automation, consumer device, robotics and security applications, or are not adopted by customers; the lengthy period of time from a design win to implementation, and the risks of cancellation or postponement of the contract or unsuccessful implementation; the risk our forward looking estimates of certain financial metrics, including but not limited to Order Book, may prove inaccurate; the risk that we may be unable to effectively manage our supply chain; the risk that the complexity of our products could result in unforeseen delays or expenses from undetected defects, errors or reliability issues in hardware or software which could reduce the market adoption of new products, damage our reputation with current or prospective customers, expose Aeva to product liability and other claims and adversely affect our operating costs; continued pricing pressures, automotive original equipment manufacturer ("OEM") cost reduction initiatives and the ability of automotive OEMs to re-source or cancel vehicle or technology programs; the risks relating to incurring substantial R&D costs and devoting significant resources to identifying and commercializing new products; uncertainty related to the market adoption of LiDAR, including Aeva's 4D LiDAR technology; the risk our transition to an outsourced manufacturing business model may not be successful; risks related to product liability or warranty claims that could result in significant direct or indirect costs to us; the risk of our high dependence on the services of Soroush Salehian Dardashti and Mina Rezk, our two founders; the potential interruption or failure of our information technology and communication systems and cybersecurity risks to our operational systems, security systems, infrastructure, integrated software in our LiDAR solutions and those risks described under "Risk Factors" of this prospectus, any prospectus supplement that we may file, and in any Annual Report on Form 10-K and any Quarterly Report on Form 10-Q incorporated by reference in this prospectus or any prospectus supplement. Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties and assumptions, the future events and trends discussed in this prospectus may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements.

You should not rely upon forward-looking statements as predictions of future events. The forward-looking statements contained in this prospectus, any prospectus supplement, the information incorporated by reference in this prospectus or any prospectus supplement, or any free writing prospectus we may authorize are based on information currently available to us and expectations and assumptions that we deem reasonable at the time the statements were made. We do not undertake any obligation to update any forward-looking statements in this prospectus, any prospectus supplement, including the information incorporated by reference in this prospectus or any prospectus supplement, any free writing prospectus we may authorize or in any of our other communications,

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except as required by law. Such forward-looking statements are subject to risks, uncertainties (some of which are beyond our control) and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements. All such forward-looking statements should be read as of the time the statements were made and with the recognition that these forward-looking statements may not be complete or accurate at a later date.

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ABOUT THIS PROSPECTUS

This prospectus is part of an automatic registration statement that we filed with the Securities and Exchange Commission (the "SEC") as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended (the "Securities Act"), utilizing a "shelf" registration process. Under this shelf registration process, we may offer and sell any combination of the securities described in this prospectus from time to time in one or more offerings, and the additional selling stockholders to be named in a supplement to this prospectus may offer and sell shares of our common stock from time to time in one or more offerings as described in this prospectus. The selling stockholder may use the shelf registration to sell up to 3,509,719 shares of common stock from time to time through any means described in the section titled "Plan of Distribution."

You should rely only on the information contained in this prospectus (as supplemented and amended), including the information incorporated by reference, or any free writing prospectus we may authorize. We and/or the selling stockholder provided the information contained in the aforementioned documents only as of the date of the applicable document, and it is possible that the information, including our business, financial condition, and results of operations, may have changed since that date.

This prospectus only provides you with a general description of the securities that we, the selling stockholder and/or any additional selling stockholder may offer. Each time we and/or any additional selling stockholder sell securities pursuant to this prospectus, we and/or such additional selling stockholder will provide a prospectus supplement that contains specific information about the terms of the offering, including the specific amounts and prices of the securities offered. In addition, the prospectus supplement may also add, update or change the information contained in this prospectus. If this prospectus is inconsistent with the prospectus supplement, you should rely upon the prospectus supplement.

We urge you to read carefully this prospectus (as supplemented and amended) before deciding whether to purchase the common stock being offered.

Neither we or the selling stockholder have authorized anyone to provide any information other than that contained or incorporated by reference in this prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. Neither we nor the selling stockholder take any responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Neither we nor the selling stockholder are making an offer of our securities in any state where the offer is not permitted. You should not assume that the information contained in or incorporated by reference in this prospectus or any prospectus supplement or in any such free writing prospectus is accurate as of any date other than their respective dates.

Unless the context otherwise requires, the terms "Aeva," "we," "us," "our," and "the Company" mean Aeva Technologies, Inc. and its subsidiaries.

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AEVA TECHNOLOGIES, INC.

Overview

Our vision is to bring perception to broad applications. Through our Frequency Modulated Continuous Wave ("FMCW") sensing technology, we believe we are introducing the world's first 4D LiDAR-on-chip that, along with our proprietary software applications, have the potential to enable the adoption of LiDAR across broad applications.

Founded in 2017 by former Apple engineers Soroush Salehian and Mina Rezk and led by a multidisciplinary team of engineers and operators experienced in the field of sensing and perception, Aeva's mission is to bring the next wave of perception technology to broad applications from automated driving, manufacturing automation and smart infrastructure, robotics and consumer devices. Our 4D LiDAR-on-chip combines silicon photonics technology that is proven in the telecom industry with precise instant velocity measurements and long-range performance for commercialization.

Unlike legacy 3D LiDAR, which relies on Time-of-Flight ("ToF") technology and measures only depth and reflectivity, Aeva's solution leverages a proprietary FMCW technology to measure velocity in addition to depth, reflectivity and inertial motion. We believe the ability of Aeva's solution to measure instant velocity for every pixel is a major advantage over ToF-based sensing solutions. Furthermore, Aeva's technology is free from interference from other LiDAR and sunlight, and our core innovations within FMCW are intended to enable vehicles to see at significantly higher distances of up to 500 meters.

We believe the advantages of our 4D LiDAR-on-chip allow us to provide the first LiDAR solution that is fully integrated onto a chip with superior performance at scale, with the potential to enable higher level of automation for vehicles and the potential to drive new categories of perception across industrial automation, consumer device applications, and security markets.

Corporate Information

Aeva Technologies, Inc. was originally incorporated in Delaware as a special purpose acquisition company on August 16, 2019 under the name InterPrivate Acquisition Corp. ("IPV"). On March 12, 2021, the Company consummated a business combination (the "Business Combination") with Aeva, Inc. In connection with the consummation of the Business Combination, the Company changed its name from IPV to Aeva Technologies, Inc. The Company's common stock is listed on the Nasdaq Global Select Market under the symbol "AEVA".

Aeva is a Delaware corporation. Our principal offices are located at 555 Ellis Street, Mountain View, CA 94043, and our telephone number is (650) 481-7070. Our website address is https://www.aeva.com. Information contained on or accessible through our website is not part of this prospectus and is not incorporated by reference herein.

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RISK FACTORS

Investing in our securities involves a high degree of risk. Before deciding whether to purchase our securities, you should consider carefully the risks and uncertainties discussed under the section titled "Risk Factors" contained in our most recent Annual Report on Form 10-K, as updated by our subsequent Quarterly Reports on Form 10-Q and other filings we make with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus and the documents incorporated by reference. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory, or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, financial condition, results of operations, or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section above titled "Special Note Regarding Forward-Looking Statements."

Sales of a substantial number of our securities in the public market by the selling stockholder or by our other existing stockholders could cause the price of our common stock to fall.

Sales of a substantial number of shares of our common stock in the public market could occur at any time.

The selling stockholder can sell, under this prospectus, up to 3,509,719 shares, representing approximately a 5.6% beneficial ownership interest of our common stock as of March 31, 2026. Sales of a substantial number of our shares of common stock in the public market by the selling stockholder or by our other existing securityholders, or the perception that those sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that such sales may have on the prevailing market price of our common stock. The sale of all the securities being offered in this prospectus could result in a significant decline in the public trading price of our securities. In addition, the registration of these shares of common stock for resale creates the possibility of a significant increase in the supply of our common stock in the market. The increased supply, coupled with the potential disparity in purchase prices, may lead to heightened selling pressure, which could negatively affect the public trading price of our common stock.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of securities as set forth in the applicable prospectus supplement.

We will not receive any proceeds from the sale of the securities by the selling stockholder or any additional selling stockholder, but in certain cases we may pay fees and expenses relating to the registration or an offering of such securities, such as registration and filing fees, fees and expenses for complying with federal and state securities laws and Nasdaq rules and regulations, and fees and expenses incurred in connection with a listing, if any, of any of the securities on any securities exchange or association.

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ADDITIONAL SELLING STOCKHOLDERS

Additional selling stockholders are persons or entities that, directly or indirectly, have acquired, or will from time to time acquire from us, our securities. Such additional selling stockholders may be parties to registration rights agreements with us, or we otherwise may have agreed or agree to register their securities for resale. The term "additional selling stockholders" includes donees, pledgees, transferees, distributees or other successors-in-interest selling shares of our common stock or interests in our common stock received after the date of this prospectus from an additional selling stockholder as a gift, pledge, partnership distribution or other transfer.

Information about additional selling stockholders, where applicable, will be set forth in a prospectus supplement, in an amendment to the registration statement of which this prospectus is a part, or in filings we make with the SEC under the Exchange Act, which are incorporated by reference.

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PLAN OF DISTRIBUTION

We may, from time to time, sell the securities offered through this prospectus in primary offerings on any stock exchange, market or trading facility on which our securities are traded or quoted or in private transactions. The selling stockholder or any additional selling stockholder may, from time to time, sell, transfer, distribute or otherwise dispose of certain of its shares of common stock or interests in our common stock on any stock exchange, market or trading facility on which shares of our common stock are traded or in private transactions. The common stock may be distributed at a fixed price or prices, which may be changed, market prices prevailing at the time of sale, prices related to the prevailing market prices, or negotiated prices.

As used in this section, the term "selling stockholders" includes donees, pledgees, transferees, distributees or other successors-in-interest selling shares of our common stock or interests in our common stock received after the date of this prospectus from the selling stockholder or any additional selling stockholder as a gift, pledge, partnership distribution or other transfer.

We or the selling stockholders may use any one or more of the following methods when selling or otherwise disposing of the securities offered by this prospectus:

A selling stockholder that is an entity may elect to make an in-kind distribution of common stock to its members, partners or stockholders pursuant to the registration statement of which this prospectus is a part by delivering a prospectus, as amended or supplemented. To the extent that such transferees are not affiliates of ours, such transferees will receive freely tradable shares of common stock pursuant to the distribution effected through this registration statement.

Each time that we or any of the selling stockholders sell securities covered by this prospectus, we or the selling stockholders will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms and conditions of the offering, including:

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Sale through underwriters or dealers

If underwriters are used in a sale by us or a selling stockholder, the underwriters will acquire the securities for their own account, including through underwriting, purchase, security lending or repurchase agreements with us. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions. Underwriters may sell the common stock in order to facilitate transactions in any of our other securities (described in this prospectus or otherwise), including other public or private transactions and short sales. Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless otherwise indicated in the applicable prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions, and the underwriters will be obligated to purchase all the offered common stock if they purchase any of them. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers. The applicable prospectus supplement will include the names of the principal underwriters, the respective amount of the securities underwritten, the nature of the obligation of the underwriters to take the securities and the nature of any material relationship between an underwriter, us and any selling stockholder.

If dealers are used in the sale of securities offered through this prospectus, we or a selling stockholder will sell the securities to them as principals. They may then resell the securities to the public at varying prices determined by the dealers at the time of resale. The applicable prospectus supplement will include the names of the dealers and the terms of the transaction.

The selling stockholder and any underwriters, broker-dealers or agents that participate in the sale of our securities or interests therein may be "underwriters" within the meaning of Section 2(11) of the Securities Act. Any discounts, commissions, concessions or profit they earn on any resale of shares of our securities may be underwriting discounts and commissions under the Securities Act. If a selling stockholder is an "underwriter" within the meaning of Section 2(11) of the Securities Act, then the selling stockholder will be subject to the prospectus delivery requirements of the Securities Act. Underwriters and their controlling persons, dealers and agents may be entitled, under agreements entered into with us and the selling stockholders, to indemnification against and contribution toward specific civil liabilities, including liabilities under the Securities Act.

Direct sales and sales through agents

We or a selling stockholder may sell the securities offered through this prospectus directly. In this case, no underwriters or agents would be involved. Such common stock may also be sold through agents designated from time to time. The applicable prospectus supplement will name any agent involved in the offer or sale of the offered securities and will describe any commissions payable to the agent by us. Unless otherwise indicated in the applicable prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

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We or a selling stockholder may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those common stock. The terms of any such sales will be described in the applicable prospectus supplement.

Selling stockholders also may resell a portion of our common stock in open market transactions in reliance upon Rule 144 under the Securities Act, provided that they meet the criteria and we and they conform to the requirements of that rule, or pursuant to other available exemptions from the registration requirements of the Securities Act.

Selling stockholders may, from time to time, pledge or grant a security interest in some shares of our common stock owned by them and, if a selling stockholder defaults in the performance of its secured obligations, the pledgees or secured parties may offer and sell such shares of common stock from time to time, under this prospectus, or under an amendment or supplement to this prospectus amending the list of the selling stockholders to include the pledgee, transferee or other successors in interest as the selling stockholders under this prospectus. The selling stockholders also may transfer shares of our common stock in other circumstances, in which case the transferees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

Delayed delivery contracts

If the applicable prospectus supplement indicates, we or a selling stockholder may authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase common stock at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future. The contracts would be subject only to those conditions described in the applicable prospectus supplement. The applicable prospectus supplement will describe the commission payable for solicitation of those contracts.

Stabilization and other transactions

Any underwriter we use in the sale of offered securities may engage in stabilizing transactions, syndicate covering transactions and penalty bids in accordance with Rule 104 under the Exchange Act. Stabilizing transactions involve bids to purchase the underlying security in the open market for the purpose of pegging, fixing or maintaining the price of the securities. Syndicate covering transactions involve purchases of the securities in the open market after the distribution has been completed in order to cover syndicate short positions.

Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a syndicate covering transaction to cover syndicate short positions. Stabilizing transactions, syndicate covering transactions and penalty bids may cause the price of the securities to be higher than it would be in the absence of the transactions. The underwriters may, if they commence these transactions, discontinue them at any time.

Derivative transactions and hedging

We, a selling stockholder, the underwriters or other agents may engage in derivative transactions involving our securities. These derivatives may consist of short sale transactions and other hedging activities. The underwriters or agents may acquire a long or short position in the securities, hold or resell securities acquired and purchase options or futures on the securities and other derivative instruments with returns linked to or related to changes in the price of the securities. In order to facilitate these derivative transactions, we may enter into security lending or repurchase agreements with the underwriters or agents. The underwriters or agents may effect the derivative transactions through sales of the common stock to the public, including short sales, or by lending the common stock in order to facilitate short sale transactions by others. The underwriters or agents may also use the securities purchased or borrowed from us or others (or, in the case of derivatives, common stock received from us in settlement of those derivatives) to directly or indirectly settle sales of the securities or close out any related open borrowings of the securities.

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Electronic auctions

We may also make sales through the Internet or through other electronic means. Since we may from time to time elect to offer securities directly to the public, with or without the involvement of agents, underwriters or dealers, utilizing the Internet or other forms of electronic bidding or ordering systems for the pricing and allocation of such securities, you should pay particular attention to the description of that system we will provide in a prospectus supplement.

Such electronic system may allow bidders to directly participate, through electronic access to an auction site, by submitting conditional offers to buy that are subject to acceptance by us, and which may directly affect the price or other terms and conditions at which such securities are sold. These bidding or ordering systems may present to each bidder, on a so-called "real-time" basis, relevant information to assist in making a bid, such as the clearing spread at which the offering would be sold, based on the bids submitted, and whether a bidder's individual bids would be accepted, prorated or rejected.

Upon completion of such an electronic auction process, securities will be allocated based on prices bid, terms of bid or other factors. The final offering price at which common stock would be sold and the allocation of common stock among bidders would be based in whole or in part on the results of the Internet or other electronic bidding process or auction.

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DESCRIPTION OF SECURITIES

This prospectus contains a summary of our capital stock, and the preferred stock, debt securities, and warrants that may be issued in the future. These summaries are not meant to be a complete description of each security. The particular terms of any security to be issued pursuant hereto will be set forth in a related prospectus supplement. This prospectus and the accompanying prospectus supplement will contain the material terms and conditions for each security.

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DESCRIPTION OF CAPITAL STOCK

The following summary of the material terms of our capital stock is not intended to be a complete summary of the rights and preferences of such securities. Because it is only a summary, it may not contain all the information that is important to an investor in our securities. Defined terms used and not defined herein shall have the meaning ascribed to such terms in our Annual Report on Form 10-K. We urge you to read our Second Amended and Restated Certificate of Incorporation ("Certificate of Incorporation") in its entirety for a complete description of the rights and preferences of our capital stock.

Our Certificate of Incorporation authorizes the issuance of 422,000,000 shares of common stock, $0.0001 par value per share and 10,000,000 shares of preferred stock, $0.0001 par value. The following description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our Certificate of Incorporation and amended and restated bylaws, each of which is incorporated by reference as an exhibit to our Annual Report on Form 10-K.

Common Stock

Voting Power

Except as otherwise required by law or as otherwise provided in any Preferred Stock Designation, the holders of the common stock possess all voting power for the election of our directors and all other matters submitted to a vote of stockholders of ours. Holders of the common stock have one vote in respect of each share of stock held by such holder on matters to be voted on by stockholders. Except as otherwise required by law, holders of the common stock, as such, are not be entitled to vote on any amendment to the Certificate of Incorporation (including any resolutions adopted by our Board of Directors approving the issue of preferred stock (a "Preferred Stock Designation")) that relates solely to the rights, powers, preferences or other terms of one or more outstanding series of our preferred stock if the holders of such affected series of our preferred stock are entitled to vote on such amendment pursuant to the Certificate of Incorporation (including any Preferred Stock Designation) or pursuant to the Delaware General Corporation Law (the "DGCL").

Dividends

Subject to applicable law and the rights and preferences of any holders of any outstanding series of preferred stock of the Company, holders of the common stock are entitled to receive dividends when, as and if declared by our Board of Directors, payable either in cash, in property or in shares of capital stock.

Liquidation, Dissolution and Winding Up

Upon our liquidation, dissolution or winding up and after payment in full of all amounts required to be paid to creditors and to any holders of our preferred stock having liquidation preferences, if any, the holders of the common stock are entitled to receive pro rata our remaining assets available for distribution.

Preemptive or Other Rights

Subject to the preferential rights of any other class or series of stock, all shares of common stock have equal dividend, distribution, liquidation and other rights, and have no preference or appraisal rights, except for any appraisal rights provided by the DGCL. Furthermore, holders of common stock have no preemptive rights and there are no conversion, sinking fund or redemption rights, or rights to subscribe for any of our securities. The rights, powers, preferences and privileges of holders of the common stock are subject to those of the holders of any shares of our preferred stock that our Board of Directors may authorize and issue in the future.

Election of Directors

Our Board of Directors is divided into three classes, each of which generally serve for a term of three years with only one class of directors being elected in each year. There is no cumulative voting with respect to the election

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of directors, with the result that the holders of more than 50% of the shares voted for the election of directors can elect all of the directors.

Classified Board of Directors

Our Certificate of Incorporation provides that our Board of Directors is divided into three classes of directors, with the classes to be as nearly equal in number as possible, and with each director serving a three-year term. As a result, approximately one-third of our Board of Directors is elected each year. The classification of directors has the effect of making it more difficult for stockholders to change the composition of our Board of Directors.

Authorized but Unissued Shares

The authorized but unissued shares of common stock and preferred stock are available for future issuance without stockholder approval, subject to any limitations imposed by the listing standards of Nasdaq. These additional shares may be used for a variety of corporate finance transactions, acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could make more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

Stockholder Action; Special Meetings of Stockholders

Our Certificate of Incorporation provides that stockholders may not take action by written consent, but may only take action at annual or special meetings of stockholders. As a result, a holder controlling a majority of our capital stock would not be able to amend our Bylaws or remove directors without holding a meeting of stockholders called in accordance with our Bylaws. This restriction does not apply to actions taken by the holders of any series of preferred stock of ours to the extent expressly provided in the applicable Preferred Stock Designation. Further, our Certificate of Incorporation provides that, subject to any special rights of the holders of preferred stock, only our Board of Directors, the chairperson of our Board of Directors or the chief executive officer of the Company's may call special meetings of stockholders, thus prohibiting a holder of our common stock from calling a special meeting. These provisions might delay the ability of stockholders to force consideration of a proposal or for stockholders controlling a majority of our capital stock to take any action, including the removal of directors.

Advance Notice Requirements for Stockholder Proposals and Director Nominations

Our Bylaws provide that stockholders seeking to bring business before our annual meeting of stockholders, or to nominate candidates for election as directors at its annual meeting of stockholders, must provide timely notice. To be timely, a stockholder's notice will need to be delivered to, or mailed and received at, our principal executive offices not less than 90 days nor more than 120 days prior to the one-year anniversary of the preceding year's annual meeting, except in the case of a special meeting to nominate candidates for election as directors, timely notice shall not less than the later of 90 days prior to the special meeting or the 10th day following the day on which public disclosure of the date of the special meeting is first made by us). In the event that the date of the annual meeting is more than 30 days before or more than 60 days after such anniversary date, to be timely, a stockholder's notice must be so delivered, or mailed and received, not later than the 90th day prior to such annual meeting or, if later, the 10th day following the day on which public disclosure of the date of such annual meeting was first made by us. Our Bylaws also specify certain requirements as to the form and content of a stockholders' notice. These provisions may preclude our stockholders from bringing matters before its annual meeting of stockholders or from making nominations for directors at its annual meeting of stockholders.

Amendment of Charter or Bylaws

Our Bylaws may be amended or repealed by our Board of Directors or by the affirmative vote of the holders of at least 66²/₃% of the voting power of all of the shares of our capital stock entitled to vote in the election of

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directors, voting as one class. The affirmative vote of the holders of at least 66²/₃% of the voting power of the then outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class, is required to amend certain provisions of our Certificate of Incorporation.

Board Vacancies

Any vacancy on our Board of Directors may be filled by a majority vote of the directors then in office, although less than a quorum, or by a sole remaining director, subject to any special rights of the holders of preferred stock. Any director chosen to fill a vacancy will hold office until the expiration of the term of the class for which he or she was elected and until his or her successor is duly elected and qualified or until their earlier resignation, removal from office, death or incapacity. Except as otherwise provided by law, the Stockholders Agreement or our Bylaws, in the event of a vacancy in our Board of Directors, the remaining directors may exercise the powers of our full Board of Directors until the vacancy is filled.

Exclusive Forum Selection

Our Certificate of Incorporation provides that unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware will, to the fullest extent permitted by applicable law, be the sole and exclusive forum for: (i) any derivative action brought by a stockholder on our behalf, (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or stockholders, (iii) any action arising under our Certificate of Incorporation, our Bylaws or the DGCL or (iv) any action asserting a claim against us governed by the internal affairs doctrine. Any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock is deemed to have notice of and consented to the exclusive forum provisions in the Certificate of Incorporation. In addition, the Certificate of Incorporation designates the federal district courts of the United States of America as the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act.

Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. As a result, the exclusive forum provision in the Certificate of Incorporation will not apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction.

Although we believe these provisions benefit us by providing increased consistency in the application of Delaware law in the types of lawsuits to which it applies, a court may determine that these provisions are unenforceable, and to the extent they are enforceable, the provisions may have the effect of discouraging lawsuits against our directors and officers, although our stockholders shall not be deemed to have waived its compliance with federal securities laws and the rules and regulations thereunder.

Section 203 of the Delaware General Corporation Law

We are subject to the provisions of Section 203 of the DGCL. In general, Section 203 prohibits a Delaware corporation that is listed on a national securities exchange or held of record by more than 2,000 stockholders from engaging in a "business combination" with an "interested stockholder" for a three-year period following the time that such stockholder becomes an interested stockholder, unless the business combination is approved in a prescribed manner. A "business combination" includes, among other things, certain mergers, asset or stock sales or other transactions resulting in a financial benefit to the interested stockholder. An "interested stockholder" is a person who, together with affiliates and associates, owns, or did own within three years prior to the determination of interested stockholder status, 15% or more of the corporation's outstanding voting stock. Under Section 203, a business combination between a corporation and an interested stockholder is prohibited unless it satisfies one of the following conditions:

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Under certain circumstances, Section 203 of the DGCL will make it more difficult for a person who would be an "interested stockholder" to effect various business combinations with a corporation for a three-year period. This provision may encourage companies interested in acquiring us to negotiate in advance with our Board of Directors because the stockholder approval requirement would be avoided if our Board of Directors approves either the business combination or the transaction which results in the stockholder becoming an interested stockholder. Section 203 of the DGCL also may have the effect of preventing changes in our Board of Directors and may make it more difficult to accomplish transactions which stockholders may otherwise deem to be in their best interests.

Preferred Stock - Limitations on Rights of Holders of Common Stock

Our Certificate of Incorporation provides that shares of our preferred stock may be issued from time to time in one or more series. Our Board of Directors is authorized to establish the voting rights, if any, designations, preferences and relative, participating, optional or other special rights of the shares of such series, and the qualifications, limitations or restrictions thereof, applicable to the shares of each series of our preferred stock. Our Board of Directors is able to, without stockholder approval, issue our preferred stock with voting and other rights that could adversely affect the voting power and other rights of the holders of our common stock and could have anti-takeover effects. The ability of our Board of Directors to issue our preferred stock without stockholder approval could have the effect of delaying, deferring or preventing a change of control of us or the removal of existing management.

Listing of Securities

Our common stock is currently listed on the Nasdaq Global Select Market under the symbol "AEVA".

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Continental Stock Transfer & Trust Company.

Limitation on Liability and Indemnification of Directors and Officers

The Certificate of Incorporation provides that our directors and officers are indemnified and advanced expenses by the Company to the fullest extent authorized or permitted by the DGCL as it now exists or may in the future be amended. In addition, the Certificate of Incorporation provides that our directors will not be personally liable to the Company or its stockholders for monetary damages for breaches of their fiduciary duty as directors to the fullest extent permitted by the DGCL.

The Certificate of Incorporation also permits us to purchase and maintain insurance on behalf of any officer, director, employee or agent of ours for any liability arising out of his or her status as such, regardless of whether the DGCL would permit indemnification.

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These provisions may discourage stockholders from bringing a lawsuit against our directors for breach of their fiduciary duty. These provisions also may have the effect of reducing the likelihood of derivative litigation against directors and officers, even though such an action, if successful, might otherwise benefit us and our stockholders. Furthermore, a stockholder's investment may be adversely affected to the extent we pay the costs of settlement and damage awards against directors and officers pursuant to these indemnification provisions. We believe that these provisions, the insurance and the indemnity agreements are necessary to attract and retain talented and experienced directors and officers.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to our directors, officers and controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

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DESCRIPTION OF DEBT SECURITIES

We have summarized below general terms and conditions of the debt securities that we may offer and sell pursuant to this prospectus. When we offer to sell a particular series of debt securities, we will describe the specific terms and conditions of the series in a prospectus supplement to this prospectus. We will also indicate in the applicable prospectus supplement whether the general terms and conditions described in this prospectus apply to the series of debt securities. The terms and conditions of the debt securities of a series may be different in one or more respects from the terms and conditions described below. If so, those differences will be described in the applicable prospectus supplement.

We will issue the debt securities in one or more series under an indenture between us and a trustee to be selected by us. The following description of provisions of the indenture does not purport to be complete and is subject to, and qualified in its entirety by reference to, the indenture, which has been filed with the SEC as an exhibit to the registration statement of which this prospectus forms a part. A form of each debt security, any future supplemental indenture or similar document also will be so filed. You should read the indenture and any supplemental indenture or similar document because they, and not this description, define your rights as holder of our debt securities. All capitalized terms have the meanings specified in the indenture.

For purposes of this section of this prospectus, references to "we," "us" and "our" are to Aeva Technologies, Inc. and not to any of its subsidiaries.

General

We may issue, from time to time, debt securities, in one or more series, that will consist of either senior debt ("Senior Debt Securities"), senior subordinated debt ("Senior Subordinated Debt Securities"), subordinated debt ("Subordinated Debt Securities") or junior subordinated debt ("Junior Subordinated Debt Securities" and, together with the Senior Subordinated Debt Securities and the Subordinated Debt Securities, the "Subordinated Securities"). Debt securities, whether senior, senior subordinated, subordinated or junior subordinated, may be issued as convertible debt securities or exchangeable debt securities.

The indenture does not limit the amount of debt securities that we may issue. We may, without the consent of the holders of the debt securities of any series, issue additional debt securities ranking equally with, and otherwise similar in all respects to, the debt securities of the series (except for any differences in the issue price and, if applicable, the initial interest accrual date and interest payment date) so that those additional debt securities will be consolidated and form a single series with the debt securities of the series previously offered and sold; provided that if the additional debt securities are not fungible with the debt securities of the series previously offered or sold for U.S. federal income tax purposes, the additional debt securities will have a separate CUSIP or other identifying number.

The indenture provides that we may issue debt securities up to the principal amount that we may authorize and may be in any currency or currency unit designated by us. Except for the limitations on consolidation, merger and sale of all or substantially all of our assets contained in the indenture, the terms of the indenture do not contain any covenants or other provisions designed to afford holders of any debt securities protection with respect to our operations, financial condition or transactions involving us.

We may issue the debt securities issued under the indenture as "discount securities," which means they may be sold at a discount below their stated principal amount. These debt securities, as well as other debt securities that are not issued at a discount, may, for U.S. federal income tax purposes, be treated as if they were issued with "original issue discount," because of interest payment and other characteristics. Special U.S. federal income tax considerations applicable to debt securities issued with original issue discount will be described in more detail in any applicable prospectus supplement.

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Provisions of the Indenture

The applicable prospectus supplement for a series of debt securities that we issue will describe, among other things, the following terms of the offered debt securities:

The applicable prospectus supplement will set forth certain U.S. federal income tax considerations for holders of any debt securities and the securities exchange or quotation system on which any debt securities are listed or quoted, if any.

Debt securities issued by us will be structurally subordinated to all indebtedness and other liabilities of our subsidiaries, except to the extent any such subsidiary guarantees or is otherwise obligated to make payment on such debt securities.

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Senior Debt Securities

Payment of the principal of, and premium, if any, and interest on, Senior Debt Securities will rank on a parity with all of our other unsecured and unsubordinated debt.

Senior Subordinated Debt Securities

Payment of the principal of, and premium, if any, and interest on, Senior Subordinated Debt Securities will be junior in right of payment to the prior payment in full of all of our unsubordinated debt. We will set forth in the applicable prospectus supplement relating to any Senior Subordinated Debt Securities the subordination terms of such securities as well as the aggregate amount of outstanding debt, as of the most recent practicable date, that by its terms would be senior to the Senior Subordinated Debt Securities. We will also set forth in such applicable prospectus supplement limitations, if any, on issuance of additional debt ranking senior to the Senior Subordinated Debt Securities.

Subordinated Debt Securities

Payment of the principal of, and premium, if any, and interest on, Subordinated Debt Securities will be subordinated and junior in right of payment to the prior payment in full of all of our unsubordinated and senior subordinated debt. We will set forth in the applicable prospectus supplement relating to any Subordinated Debt Securities the subordination terms of such securities as well as the aggregate amount of outstanding indebtedness, as of the most recent practicable date, that by its terms would be senior to the Subordinated Debt Securities. We will also set forth in such prospectus supplement limitations, if any, on issuance of additional debt ranking senior to the Subordinated Debt Securities.

Junior Subordinated Debt Securities

Payment of the principal of, and premium, if any, and interest on, Junior Subordinated Debt Securities will be subordinated and junior in right of payment to the prior payment in full of all of our unsubordinated, senior subordinated and subordinated debt. We will set forth in the applicable prospectus supplement relating to any Junior Subordinated Debt Securities the subordination terms of such securities as well as the aggregate amount of outstanding debt, as of the most recent practicable date, that by its terms would be senior to the Junior Subordinated Debt Securities. We will also set forth in such prospectus supplement limitations, if any, on issuance of additional debt ranking senior to the Junior Subordinated Debt Securities.

Conversion or Exchange Rights

Debt securities may be convertible into or exchangeable for other securities or property of us. The terms and conditions of conversion or exchange will be set forth in the applicable prospectus supplement. The terms will include, among others, the following:

Consolidation, Merger or Sale

We cannot consolidate or merge with or into, or transfer or lease our properties and assets substantially as an entirety to, any person, and we shall not permit any other person to consolidate with or merge into us, unless:

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Subject to certain exceptions, when the person to whom our assets are transferred or leased has assumed our obligations under the debt securities and the indenture, we shall be discharged from all our obligations under the debt securities and the indenture.

This covenant would not apply to any recapitalization transaction, a change of control of us or a highly leveraged transaction, unless the transaction or change of control were structured to include a merger or consolidation or transfer or lease of our properties and assets substantially as an entirety.

Events of Default

Unless otherwise indicated, the term "Event of Default," when used in the indenture with respect to the debt securities of any series, means any of the following:

An Event of Default for a particular series of debt securities does not necessarily constitute an Event of Default for any other series of debt securities issued under the indenture.

If an Event of Default (other than an Event of Default relating to events of bankruptcy, insolvency or reorganization of us) involving any series of debt securities has occurred and is continuing, the trustee or the holders of a specified aggregate principal amount of the debt securities of each affected series may declare the entire principal amount of all the debt securities of such affected series, and the interest accrued thereon, if any, to be due and payable immediately. The holders of not less than a majority in aggregate principal amount of the debt securities of an affected series may, after satisfying conditions, rescind and annul any of the above-described declarations and consequences involving such series.

If an Event of Default relating to events of bankruptcy, insolvency or reorganization of us occurs and is continuing, then the entire principal amount of all of the debt securities outstanding, and the interest accrued thereon, if any, will automatically become due and payable immediately, without any declaration or other act by the trustee or any holder.

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The indenture imposes limitations on suits brought by holders of debt securities against us with respect to an Event of Default. Except as provided below, no holder of debt securities of any series may institute any action against us under the indenture unless:

Notwithstanding the foregoing, each holder of debt securities of any series has the right, which is absolute and unconditional, to receive payment of the principal of, and premium and interest, if any, on, such debt securities when due and to institute suit for the enforcement of any such payment, and such rights may not be impaired without the consent of that holder of debt securities.

We will be required to file annually with the trustee a certificate, signed by one of our officers, stating whether or not the officer knows of any default by us in the performance, observance or fulfillment of any condition or covenant of the indenture.

Registered Global Securities

We may issue the debt securities of a series in whole or in part in the form of one or more fully registered global securities that we will deposit with a depositary or with a nominee for a depositary identified in the applicable prospectus supplement and registered in the name of such depositary or nominee. In such case, we will issue one or more registered global securities denominated in an amount equal to the aggregate principal amount of all of the debt securities of the series to be issued and represented by such registered global security or securities.

Unless and until it is exchanged in whole or in part for debt securities in definitive registered form, a registered global security may not be transferred except as a whole:

The applicable prospectus supplement relating to a series of debt securities will describe the specific terms of the depositary arrangement with respect to any portion of such series represented by a registered global security. We anticipate that the following provisions will apply to all depositary arrangements for debt securities:

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The laws of some states may require that certain purchasers of securities take physical delivery of the securities in definitive form. These laws may limit the ability of those persons to own, transfer or pledge beneficial interests in registered global securities.

So long as the depositary for a registered global security, or its nominee, is the registered owner of the registered global security, the depositary or the nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by the registered global security for all purposes under the indenture. Except as set forth below, owners of beneficial interests in a registered global security:

Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for the registered global security and, if the person is not a participant, on the procedures of a participant through which the person owns its interest, to exercise any rights of a holder under the indenture.

We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder is entitled to give or take under the indenture, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take the action, and those participants would authorize beneficial owners owning through those participants to give or take the action or would otherwise act upon the instructions of beneficial owners holding through them.

We will make payments of principal and premium, if any, and interest, if any, on debt securities represented by a registered global security registered in the name of a depositary or its nominee to the depositary or its nominee, as the case may be, as the registered owners of the registered global security. None of us, the trustee or any other agent of us or the trustee will be responsible or liable for any aspect of the records relating to, or payments made on account of, beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to the beneficial ownership interests.

We expect that the depositary for any debt securities represented by a registered global security, upon receipt of any payments of principal and premium, if any, and interest, if any, in respect of the registered global security, will immediately credit participants' accounts with payments in amounts proportionate to their respective beneficial interests in the registered global security as shown on the records of the depositary. We also expect that standing customer instructions and customary practices will govern payments by participants to owners of beneficial interests in the registered global security held through the participants, as is now the case with the securities held for the accounts of customers in bearer form or registered in "street name." We also expect that any of these payments will be the responsibility of the participants.

If the depositary for any debt securities represented by a registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act, we will

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appoint an eligible successor depositary. If we fail to appoint an eligible successor depositary within 90 days, we will issue the debt securities in definitive form in exchange for the registered global security. In addition, we may at any time and in our sole discretion decide not to have any of the debt securities of a series represented by one or more registered global securities. In such event, we will issue debt securities of that series in a definitive form in exchange for all of the registered global securities representing the debt securities. The trustee will register any debt securities issued in definitive form in exchange for a registered global security in such name or names as the depositary, based upon instructions from its participants, shall instruct the trustee.

Discharge, Defeasance and Covenant Defeasance

We can discharge or defease our obligations under the indenture as set forth below. Unless otherwise set forth in the applicable prospectus supplement, the subordination provisions applicable to any Subordinated Securities will be expressly made subject to the discharge and defeasance provisions of the indenture.

We may discharge our obligations to holders of any series of debt securities that have not already been delivered to the trustee for cancellation and that have either become due and payable or are by their terms to become due and payable within one year (or to be called for redemption within one year). We may effect a discharge by irrevocably depositing with the trustee cash or U.S. government obligations, as trust funds, in an amount certified to be sufficient to pay when due, whether at maturity, upon redemption or otherwise, the principal of, and premium, if any, and interest on, the debt securities and any mandatory sinking fund payments.

Unless otherwise provided in the applicable prospectus supplement, we may also discharge any and all of our obligations to holders of any series of debt securities at any time ("legal defeasance"). We also may be released from the obligations imposed by any covenants of any outstanding series of debt securities and provisions of the indenture, and we may omit to comply with those covenants without creating an Event of Default ("covenant defeasance"). We may effect legal defeasance and covenant defeasance only if, among other things:

Although we may discharge or defease our obligations under the indenture as described in the two preceding paragraphs, we may not avoid, among other things, our duty to register the transfer or exchange of any series of debt securities, to replace any temporary, mutilated, destroyed, lost or stolen series of debt securities or to maintain an office or agency in respect of any series of debt securities.

We may exercise our legal defeasance option notwithstanding our prior exercise of our covenant defeasance option.

Modifications of the Indenture

The indenture provides that we and the trustee may enter into supplemental indentures without the consent of the holders of debt securities to:

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The indenture also provides that we and the trustee may, with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding debt securities of all series of Senior Debt Securities or Subordinated Securities, as the case may be, then outstanding and affected thereby (voting as one class), add any provisions to, or change in any manner, eliminate or modify in any way the provisions of, the indenture or modify in any manner the rights of the holders of the debt securities. We and the trustee may not, however, without the consent of the holder of each outstanding debt security affected thereby:

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Concerning the Trustee

The indenture provides that there may be more than one trustee under the indenture, each with respect to one or more series of debt securities. If there are different trustees for different series of debt securities, each trustee will be a trustee of a trust under the indenture separate and apart from the trust administered by any other trustee under the indenture. Except as otherwise indicated in this prospectus or any accompanying prospectus supplement, any action permitted to be taken by a trustee may be taken by such trustee only with respect to the one or more series of debt securities for which it is the trustee under the indenture. Any trustee under the indenture may resign or be removed with respect to one or more series of debt securities. All payments of principal of, and premium, if any, and interest on, and all registration, transfer, exchange, authentication and delivery (including authentication and delivery on original issuance of the debt securities) of, the debt securities of a series will be effected by the trustee with respect to such series at an office designated by the trustee.

The indenture contains limitations on the right of the trustee, should it become a creditor of us, to obtain payment of claims in some cases or to realize on certain property received in respect of any such claim as security or otherwise. The trustee may engage in other transactions. If it acquires any conflicting interest relating to any duties with respect to the debt securities, however, it must eliminate the conflict or resign as trustee.

The holders of a majority in aggregate principal amount of any series of debt securities then outstanding will have the right to direct the time, method and place of conducting any proceeding for exercising any remedy available to the trustee with respect to such series of debt securities, provided that the direction would not conflict with any rule of law or with the indenture, would not be unduly prejudicial to the rights of another holder of the debt securities, and would not involve any trustee in personal liability. The indenture provides that in case an Event of Default shall occur and be known to any trustee and not be cured, the trustee must use the same degree of care as a prudent person would use in the conduct of his or her own affairs in the exercise of the trustee's power. Subject to these provisions, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request of any of the holders of the debt securities, unless they shall have offered to the trustee security and indemnity satisfactory to the trustee.

No Individual Liability of Incorporators, Stockholders, Officers or Directors

The indenture provides that no incorporator and no past, present or future stockholder, officer or director of us or any successor corporation in their capacity as such shall have any individual liability for any of our obligations, covenants or agreements under the debt securities or the indenture.

Governing Law

The indenture and the debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

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DESCRIPTION OF WARRANTS

General

We may issue debt warrants for the purchase of debt securities or stock warrants for the purchase of preferred stock or common stock.

The warrants will be issued under warrant agreements to be entered into between us and the purchasers or between us and a bank or trust company, as warrant agent, all to be set forth in the applicable prospectus supplement relating to any or all warrants in respect of which this prospectus is being delivered. We will file a copy of the warrant and warrant agreement with the SEC each time we issue a series of warrants, and these warrants and warrant agreements will be incorporated by reference into the registration statement of which this prospectus forms a part.

The following description sets forth certain general terms and provisions of the warrants to which any applicable prospectus supplement may relate. The particular terms of the warrants to which any applicable prospectus supplement may relate and the extent, if any, to which such general provisions may apply to the warrants so offered will be described in the applicable prospectus supplement. The following summary of certain provisions of the warrants, warrant agreements and warrant certificates does not purport to be complete and is subject to, and is qualified in its entirety by express reference to, all the provisions of the warrant agreements and warrant certificates, including the definitions therein of certain terms.

Debt Warrants

General. Reference is made to the applicable prospectus supplement for the terms of debt warrants in respect of which this prospectus is being delivered, the debt securities warrant agreement relating to such debt warrants and the debt warrant certificates representing such debt warrants, including the following:

The debt warrant certificates will be exchangeable for new debt warrant certificates of different denominations and debt warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the debt securities purchasable upon such exercise and will not be entitled to any payments of principal and premium, if any, and interest, if any, on the debt securities purchasable upon such exercise.

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Exercise of Debt Warrants. Each debt warrant will entitle the holder to purchase for cash such principal amount of debt securities at such exercise price as shall in each case be set forth in, or be determinable as set forth in, the applicable prospectus supplement relating to the debt warrants offered thereby. Unless otherwise specified in the applicable prospectus supplement, debt warrants may be exercised at any time up to 5:00 p.m., New York City time, on the expiration date set forth in the applicable prospectus supplement. After 5:00 p.m., New York City time, on the expiration date, unexercised debt warrants will become void.

Debt warrants may be exercised as set forth in the applicable prospectus supplement relating to the debt warrants. Upon receipt of payment and the debt warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will, as soon as practicable, forward the debt securities purchasable upon such exercise. If less than all of the debt warrants represented by such debt warrant certificate are exercised, a new debt warrant certificate will be issued for the remaining amount of debt warrants.

Stock Warrants

General. Reference is made to the applicable prospectus supplement for the terms of stock warrants in respect of which this prospectus is being delivered, the stock warrant agreement relating to such stock warrants and the stock warrant certificates representing such stock warrants, including the following:

The stock warrant certificates will be exchangeable for new stock warrant certificates of different denominations and stock warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their stock warrants, holders of stock warrants will not have any of the rights of holders of shares of capital stock purchasable upon such exercise, and will not be entitled to any dividend payments on such capital stock purchasable upon such exercise.

Exercise of Stock Warrants. Each stock warrant will entitle the holder to purchase for cash such number of shares of preferred stock or common stock, as the case may be, at such exercise price as shall in each case be set forth in, or be determinable as set forth in, the applicable prospectus supplement relating to the stock warrants offered thereby. Unless otherwise specified in the applicable prospectus supplement, stock warrants may be exercised at any time up to 5:00 p.m., California time, on the expiration date set forth in the applicable prospectus supplement. After 5:00 p.m., California time, on the expiration date, unexercised stock warrants will become void.

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Stock warrants may be exercised as set forth in the applicable prospectus supplement relating thereto. Upon receipt of payment and the stock warrant certificates properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will, as soon as practicable, forward a certificate representing the number of shares of capital stock purchasable upon such exercise. If less than all of the stock warrants represented by such stock warrant certificate are exercised, a new stock warrant certificate will be issued for the remaining amount of stock warrants.

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SELLING STOCKHOLDER

As previously disclosed, on May 13, 2025, we entered into a subscription agreement with the selling stockholder, pursuant to which we agreed to sell and issue in a private placement (the "Private Placement") an aggregate of 3,509,719 shares of common stock at a price of $9.26 per share, for aggregate gross proceeds of approximately $32.5 million. The closing of the Private Placement occurred on August 20, 2025. This prospectus covers the resale or other disposition from time to time by the selling stockholder of the resale shares that were issued to the selling stockholder by us in the Private Placement. We are registering the offer and sale of the resale shares to satisfy certain registration obligations that we granted the selling stockholder in connection with the Private Placement.

The following table sets forth certain information provided by or on behalf of the selling stockholder concerning the common stock that may be offered from time to time by such selling stockholder pursuant to this prospectus. The selling stockholder identified below may have sold, transferred, or otherwise disposed of all or a portion of their securities after the date on which they provided us with information regarding their securities. Any changed or new information given to us by the selling stockholder, including regarding the identity of, and the securities held by, such selling stockholder, will be set forth in a prospectus supplement or amendments to the registration statement of which this prospectus is a part, if and when necessary. The selling stockholder may sell all, some or none of such securities in this offering. See "Plan of Distribution."

The table is based on information supplied to us by the selling stockholder, with beneficial ownership and percentage ownership determined in accordance with the rules and regulations of the SEC. This information does not necessarily indicate beneficial ownership for any other purpose. We have based our calculation of the percentage of beneficial ownership of the selling stockholder before the offering on 62,984,603 shares of common stock outstanding as of March 31, 2026. Percentage ownership of shares of our common stock after this offering gives effect to the sale by the selling stockholder of 3,509,719 shares of our common stock in this offering. The information in this table assumes the sale of all shares offered by the selling stockholder and that the selling stockholder does not acquire any additional shares.

The registration for resale of the shares does not mean that the selling stockholder will sell or otherwise dispose of all or any of these shares of common stock. The selling stockholder may sell or otherwise dispose of all, a portion or none of such shares from time to time. We do not know the number of shares, if any, that will be offered for sale or other disposition by the selling stockholder under this prospectus. We currently have no agreements, arrangements or understandings with the selling stockholder regarding the sale of any of the shares.

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LEGAL MATTERS

The validity of the securities being offered hereby is being passed upon for us by Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP, Redwood City, California. As appropriate, any underwriters will also be advised about the validity of the securities and other legal matters by their own counsel, which will be named in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements incorporated in this prospectus by reference have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report. Such financial statements are incorporated in reliance upon the report of such firm given their authority as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at https://www.aeva.com. Information accessible on or through our website is not incorporated herein or a part of this prospectus.

This prospectus is part of a registration statement we filed with the SEC. This prospectus omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information on us and the securities we or the selling stockholder are offering. Statements in this prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements.

INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC to the extent set forth herein, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated by reference in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below and any future filings that we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (in each case, other than those documents or the portions of those documents furnished (but not filed) pursuant to Items 2.02 or 7.01 of any Current Report on Form 8-K), until the offering of the common stock being registered under this prospectus is terminated or completed:

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We will provide without charge to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, upon written or oral request of any such person, a copy of any or all of the documents that have been or may be incorporated by reference into this prospectus at no cost. Any such request may be made in writing or by telephoning us at the following address or telephone number:

Aeva Technologies, Inc.

555 Ellis Street

Mountain View, CA 94043

(650) 481-7070

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$100,000,000

Common Stock

PROSPECTUS SUPPLEMENT

Joint Book-Running Managers

, 2026