How to check the battery of a used EV
SOH, charging behavior, warranty, and practical checks before buying a used electric car.
Why the battery is the central risk
In a used electric car, the battery is the most expensive component and usually the hardest to assess without diagnostics. The range shown on the dashboard isn't enough on its own — it depends on recent driving, temperature, tires, climate control, and the car's own software estimate.
SOH is a useful signal, but not a universal guarantee. Different brands use different measurement methods. Some display a value directly through the BMS, others require a service tool, and some only offer indirect parameters.
Minimum check
- Compare the advertised SOH against a report from an independent diagnostic check.
- Check whether there's a battery warranty and whether it's transferable.
- Take a test drive with at least a partially warmed battery.
- Test AC charging and, if possible, DC fast charging.
- Check for warning lights or reduced power output.
What to ask the seller
Ask when the last diagnostic check was done, whether the battery has been repaired, whether any modules have been replaced, and whether the car sat for long periods at very low or very high charge levels. Ask for documents, not just verbal assurances.
Legal and financial context
FindVolta does not guarantee the SOH values shown in listings. The platform displays data entered by the seller or structured by the system, but this does not replace an independent technical inspection. Before paying, have the car checked by a workshop that isn't a party to the deal.