What does SOH mean on a battery report?
SOH stands for State of Health. It describes the condition of the drive battery relative to its original condition, using the test’s assessment method. It is usually shown as a percentage. Read that figure with the test method and supporting findings, rather than treating it as a complete verdict on the car.
For a used electric car or plug-in hybrid, a battery health check provides information to consider alongside the vehicle’s history, condition and suitability for your journeys.
SOH versus State of Charge: what is the difference?
| Reading | What it tells you |
|---|---|
| State of Charge (SOC) | How full the battery is now. It rises when you charge and falls as you use energy. |
| State of Health (SOH) | The battery’s assessed condition relative to its original condition, according to the test method. |
Charging to 100% fills the battery to its current usable limit. It does not restore lost capacity or prove that the battery is as healthy as when it was new.
Does SOH show battery degradation?
Battery degradation means a change in performance or capacity as the battery ages and is used. SOH can help assess that change, but it is an estimate based on a particular method. It is not a countdown of the battery’s remaining years.
Where a report defines SOH as retained capacity, a result of 90% means approximately 90% of the new-battery reference used by that method. It does not promise exactly 90% of the car’s original driving range: weather, speed, heating and driving conditions also affect range.
What is a good SOH for a used EV?
There is no single percentage that makes every used EV a good or bad purchase. Consider its age, mileage, battery type, test method, other findings and the range you need. A high SOH alone cannot rule out every battery fault.
Ask for a dated report that identifies the car and the test. Check any battery warranty terms separately with the manufacturer; an independent report does not guarantee a warranty claim will be accepted.
Why can Autel and AVILOO show different results?
Both use vehicle battery information, but apply different assessment and reporting methods. AVILOO FLASH applies its own analysis and provides a separate certificate. Different percentages do not necessarily mean that the battery changed between tests.
Our BMW 330e sample reports recorded 96% with Autel and 93.3% with AVILOO on the same day. These are results for that particular car. Read the reports separately; averaging the figures does not create a valid new test result.
Compare the Autel SOH Blitz and AVILOO FLASH checks or open the sample battery reports.
How do I book an EV SOH test in Dublin or Leinster?
BatteryReport.ie provides mobile electric car and plug-in hybrid battery health checks at your home, workplace or the seller’s location, with the owner’s permission. Give Eoghan the make, model, year, battery version if known and appointment Eircode so compatibility can be checked.
The Autel check costs €129 in Dublin or €179 in Meath, Kildare, Wicklow and Louth, including a free diagnostic scan of supported electronic systems. All other counties are priced on request. Add AVILOO FLASH for €40. These are checks of the high-voltage drive battery; they do not replace a full physical vehicle inspection.
For the wider purchase decision, use our used EV buying checklist for Ireland.
Further reading
SEAI: buying a used EV · AVILOO: certificate methodology and limitations