Used EV shoppers lack critical battery health information

Automaker practices for collecting data on used batteries vary. General Motors collects data, with customer consent, on battery capacity, charging events, state of charge and other diagnostic information via OnStar.

“We’ll have more to share in the future” on making that data available to owners and shoppers, said Natalee Runyan, senior manager in GM’s electrification communications group.

Ford declined to provide testing details.

“A Ford dealer’s checklist for pre-owned EV sale includes parameters that also apply to gas-powered products,” said Charles Poon, global director of electrified systems engineering at the automaker. “Specific to EVs, we [inspect] cooling systems, charging systems, vehicle cluster and underbody damage — including the battery.”

Hyundai assesses battery capacity via a scan tool used by its dealers. In the future, the automaker plans to publish the battery pack’s state of health on the window sticker or in the inspection report of certified pre-owned vehicles, said spokesperson Miles Johnson.

VW collects no data on battery condition during vehicle operation, said Mark Gillies, Volkswagen Group of America spokesperson. But its dealer diagnostic tools offer two tests. The first, which takes several hours, is part of the certification process for a certified pre-owned vehicle. A shorter second test provides current state of health (in percent of original capacity) that can be released to customers who may, for instance, question the range of a vehicle.

All four automakers warrant batteries against total failure for eight years or 100,000 miles. Hyundai and VW said if capacity falls below 70 percent of the original battery, the pack would be replaced under warranty. GM’s warranty is higher — 75 percent of original capacity.