ChargeX Consortium Identifies Automated Solution To Fix Key Part of Electric Vehicle Charging User Experience

ChargeX Consortium Identifies Automated Solution To Fix Key Part of Electric Vehicle Charging User Experience

National laboratory researchers and industry collaborators in the National Charging Experience Consortium (ChargeX Consortium) have identified a new mechanism called "seamless retry" that could alleviate a common electric vehicle (EV) driver frustration with public charging by automatically restarting failed EV charging sessions, so users do not have to.

While the current public charging network offers EV drivers more than 205,000 places to charge across the nation-a number that continues to grow in real time-there is a continued need to improve the reliability of these charging options for drivers while they are away from home.

The rapid rollout of the number of public charging locations across the nation has boosted convenience for EV drivers. However, sometimes user intervention is still needed to restart the direct-current (DC) fast charging EV charging sessions if they fail to initiate. Currently, a simple unplug and replug of the charging connector can quickly fix the problem but puts the burden on the user to manually restart the charging session.

To reduce the need for user interventions when EV charging fails to initiate by automatically restarting failed sessions, researchers participating in the ChargeX Consortium from the National Renewable Energy Laboratory (NREL), Idaho National Laboratory (INL), and Argonne National Laboratory (ANL), along with industry contributors recently released a new report detailing the benefits of a new hands-free, tech-enabled mechanism aptly named "seamless retry."

"Seamless retry directly impacts how the driver interacts with their vehicle and EV charging infrastructure," said Kristi Moriarty, a senior transportation researcher at NREL and a ChargeX Consortium lead "By resolving a variety of session failure types automatically, we have unlocked a significantly scalable way of improving users' future charging experiences."

Automation To Improve the User Experience

The ChargeX Consortium identified the seamless retry mechanism as a viable solution to boost operational efficiency, demonstrate potential for intelligent design through automation, resolve a common technical challenge, and unburden drivers who previously have had to manually restart charging sessions that failed to initiate. Put simply, the user no longer needs to physically get out of their car to unplug and replug the charging connector when a charging session fails.

The consortium's novel mechanism can specifically be applied to DC fast charging scenarios where an unplug and replug of the charging connector resolves the failure. Seamless retry makes the restart invisible by automatically resetting the vehicle and EV charging infrastructure and initiating the new charge.

As public charging stands currently, if a user starts a session and leaves the vehicle for a period of time, they may return to a car with little to no charge because the charging session failed to initiate. While it is possible for the user to currently receive a failed charging session alert through an application or text message, without seamless retry, the user must physically return to the vehicle to restart the charging session.

"The added convenience of seamless retry is what makes this approach so beneficial to adopt," said Ed Watt, a researcher at NREL and lead author of the Recommended Practice Seamless Retry for Electric Vehicle Charging report. "With a seamless retry mechanism in place, an EV driver at a retail center can plug in a charging connector, provide user input data, leave to shop, and feel confident that they will return to a charged vehicle."

ChargeX researchers also considered deterrents of seamless retry as part of their new findings. During a charging session, the user may become frustrated at the additional time required to start charging due to seamless retry. To address this potential downside, the consortium mentioned that the EV industry should consider integrating additional system information provided to the user during the seamless retry process, such as status updates, recommendations based on type of charging failure, and number of attempts made.

Seamless Retry Future Work

As the user experience is defined and further understood, additional work will help advance the seamless retry mechanism. The ChargeX Consortium's future work in this area will continue to evolve to include developing more targeted retry methods, additional implementation details, and verification test cases.

The ChargeX Consortium is a convening of ANL, INL, NREL, and industry stakeholders, with research funded by the Joint Office of Energy and Transportation. The consortium unites private and public stakeholders to solve EV charging challenges and create recommendations to improve the EV charging user experience at scale.

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