Guide · Battery check
Where to get the battery check for a used EV — and whether you can do it yourself
The battery is the most expensive part of an electric car and the biggest unknown when buying used. The good news: in Switzerland you can have its condition assessed independently and do not depend on the goodwill of the seller. Here is who does it, what it costs and whether you can do it yourself.
Two kinds of test
Both measure the «state of health» (SoH), that is the capacity remaining compared with the new condition — but with differing thoroughness.
- Flash test: around 20 minutes via the diagnostic port, on site, certificate immediately. A snapshot. Good for a quick, standardised figure.
- Premium or used-car test: the precise one. A device records a full discharge run, from 100 down to below 10 per cent, evaluates millions of data points and also identifies individual weak cells. More effort, more precise, certificate in about two working days.
Who offers it in Switzerland
- TCS. Offers the Aviloo flash test at its vehicle inspection centres. In the canton of Zurich CHF 75 for members, CHF 115 for non-members; the more comprehensive used-EV test CHF 255 and CHF 330 respectively. Prices differ by TCS section. The TCS was the first provider of this standardised test in Switzerland, supported by EnergieSchweiz.
- ACS. The Automobile Club of Switzerland works with Aviloo and arranges the premium test, certificate by email within two working days. Members receive special terms.
- AXA. The insurer has offered its customers discounted access to the Aviloo test since 2023. Here too the same procedure sits behind it.
- Aviloo directly. The Austrian company is behind both tests. You can order the premium test directly, from around 99 euros — device by post, you drive, certificate by email.
- Garages. Many workshops, the eGarage partners among them, carry out the Aviloo test on site.
- The seller. More and more often a certificate is already included, on the used-car platforms as well. Check the date in that case: a two-year-old certificate describes a different condition.
Worth knowing: those are many doors, but almost always the same provider stands behind them. TCS, ACS, AXA and most garages all resell the Aviloo procedure. An equivalent, independent competing certificate is currently all but absent from the Swiss market. The SoH figure that the car itself reports via the diagnostic port is no substitute — it is manufacturer-specific and not comparable across brands.
Do not confuse the two — insurance is not a test. An EV insurance policy with battery cover, such as «Elektro-Plus» at Zurich, replaces the battery in the event of damage or covers harm caused by incorrect charging. It tells you nothing about the state of health of the battery. A battery test measures exactly that condition, but does not help you when the battery fails. One protects your wallet, the other your purchase decision. AXA appears in the list above because it arranges the test — not because of its insurance. The safety check an insurer performs after a repair is not an SoH certificate either.
For the price negotiation you do not need an expensive device, you need a certificate issued by someone independent.
Can you do it yourself?
Partly yes, and that surprises many. The premium test is a self-test at its core: the device arrives by post, you run the battery down yourself, upload the data and receive the certificate — with no workshop appointment at all.
It gets cheaper still with a simple OBD adapter for 20 to 50 francs and an app such as Car Scanner or, for Nissan, LeafSpy. On many models these read out a raw SoH value. Two catches: it depends on the model and you have to be able to judge the figure yourself — and it is not an independent, standardised certificate to put in front of a seller or a manufacturer. For your own peace of mind the adapter is enough. As evidence in a negotiation it is worthless.
What the test does not answer
An SoH test measures capacity and cells. It does not check the mechanics and the periphery of the battery — housing, seals, sensors, pumps, cables. The TCS states this explicitly. And a flash snapshot is less exact than a full discharge run. It also holds that SoH is not simply SoH: different procedures do not deliver the same value. Anyone reading the figure should know what it covers and what it does not.
What the SoH value means exactly, and which figure is good or bad, is set out in the used-or-new tab under «Checking the battery».
Sources: TCS (Aviloo flash test, used-EV test), prices for the canton of Zurich via Blick (March 2025); ACS press release on the Aviloo partnership; Aviloo (premium test, certificate); EnergieSchweiz (electric mobility roadmap). Prices vary by TCS section and over time — check before booking.
