Quick answer
Key takeaways
- Battery “state of health” is not published by DVLA or DVSA and doesn’t appear on the MOT.
- The clearest signal is expected real-world range now versus when the car was new.
- A battery-health grade is only available where a manufacturer test record exists.
- You can get all of this from just the registration and current mileage, before you view the car.
Why battery health decides a used EV's value
With a petrol car, mileage and service history tell most of the story. With an electric car they don't. The battery is the single most expensive component, and two identical models on the same mileage can be worth very different amounts depending on how their packs have been charged, used and stored. A car kept on rapid chargers and left sitting at 100% degrades faster than one home-charged to 80%, and none of that shows up on the V5C, the MOT or the advert.
That's why checking battery health matters more than almost anything else when you buy a used EV. Get it wrong and you could pay for range the car can no longer deliver.
What “battery health” actually means
Three related things get bundled under “battery health”:
- State of health (SoH), the battery's usable capacity now as a percentage of when it was new. A measured SoH needs an OBD test on the car itself.
- Degradation, how much capacity (and therefore range) the pack has lost over time. Some early loss is normal; a steep drop is not.
- Real-world range now, the practical number that matters: how far the car will actually go today, which is lower than the WLTP figure and lower again in winter.
For a fuller explanation, see our guide to what's normal for EV battery degradation.
Five ways to check a used EV's battery health
| Method | What it tells you | Needs the car? |
|---|---|---|
| Dashboard range at 100% | Rough guide to remaining range | Yes |
| Battery-health check by reg | Estimated range now vs new, degradation, warranty left | No, just the plate |
| Physical OBD / SoH test | Measured state of health | Yes, plus a specialist |
| Service & charging history | How the car has been used and charged | Paperwork / seller |
| MOT & mileage history | Usage pattern and any clocking | No |
The dashboard and a physical test both need the car in front of you, useful once you're there, but no help when you're deciding whether a car 100 miles away is even worth the trip. That's the gap a reg-based check fills.
How to check battery health from just the registration
The Used EV Check models battery health from real-world fleet data for the specific car. Enter the UK registration and current mileage and it returns:
- Expected real-world range now versus when the car was new
- An estimated degradation figure for that specific vehicle
- A battery-health grade, shown where a manufacturer test record exists (a comparative grade, not a measured SoH percentage)
- Remaining battery warranty in miles and months
- Full MOT and mileage history to expose clocking or heavy use
It runs before you view the car, so you can rule out tired cars from the listing and compare two candidates on the same basis. Range data is powered by ClearWatt.
What a good result looks like
A healthy used EV shows an expected range now that's close to its original figure for the car's age and mileage, a modest degradation estimate, and plenty of battery warranty still in hand. A car showing a big gap between its new and current range, especially a younger, lower-mileage one, deserves more questions, or a walk away.
Range and battery-health figures are estimates modelled from real-world data and are shown for the specific vehicle in the Used EV Check. Range data is powered by ClearWatt. A battery-health grade is shown where a manufacturer test record exists, it is a comparative grade, not a measured state-of-health percentage.
Check a used EV before you buy
Enter a registration to see a used EV's battery health, real-world range now vs when new and remaining battery warranty, an instant report for £9.99.
Frequently asked questions
Can you check an EV battery health by registration?+
Is a battery-health grade the same as state of health?+
Do I still need a physical battery test?+
How much does it cost to check an EV’s battery health?+
Related guides
Battery & Range
EV battery degradation
How much do EV batteries really degrade? What a normal degradation rate looks like by age and mileage, the warning signs of a tired pack, and how to estimate a used EV's degradation before you buy.
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Real-world EV range
WLTP range vs the range a used EV actually delivers. Why the advert figure is optimistic, how much range a second-hand EV loses with age and cold, and how to check the real-world range now.
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EV battery warranty
How electric car battery warranties work, the typical 8-year/100,000-mile capacity cover, what triggers a claim, how much transfers to you, and how to check the warranty remaining on a used EV.