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the essentials in 22 minutesBattery SoH explained: what the figure means for a used EV
The SoH figure shows how much capacity the battery still has. Which value is normal at which age, why two measurements can differ, and what buyers and sellers can do with the number.
Read →then:2 · Why one figure is not enough3 · How long does the battery last?4 · All testing routes compared5 · What a certificate must deliver
Buying & Selling
5 articlesSelling an EV on Kleinanzeigen: Proving Battery Health
How to put your Tesla's battery proof into a Kleinanzeigen ad so buyers believe it: as a gallery photo with a QR code, as a short link in the text, and in chat. Turn the battery question into your best argument.
Updated: 19 August 2026Selling a Used Tesla: How to Prevent the Battery Price Discount
Buyers push the price down with battery anxiety — often by four-figure amounts. How to prove your pack's condition, structure the listing right, and flip the burden of proof in the negotiation.
EV Battery Certificates: Cost, Rules, What They Prove (2026)
What a battery certificate is, which types exist, what they cost, when uploading one is mandatory — and how to spot a certificate worth trusting.
Whoever Measures Has a Stake: What Makes a Battery Certificate Independent
Warranty claims and residual values both hang on the SoH figure, and the manufacturer carries the cost of either. Why that is a structural conflict of interest, how some manufacturers solve it themselves, and how to spot an issuer without one.
Will a Battery Certificate Hold Up in Court?
No battery certificate binds a court — not one from a large inspection group either. How German courts treat these documents, the four properties that make a certificate usable, and what buyers and sellers should do about it.
Testing & Measuring
4 articlesTesla's Built-In Battery Health Test: Steps, Duration, Limits (2026)
How the in-car battery health test works, why it often refuses to start, how long it really takes and why Tesla is currently removing it from many cars.
Updated: 22 August 2026Read the SoH or Measure It? What the Garage Figure Can and Cannot Tell YouNew
At a franchised garage or through an OBD dongle, the SoH is read out of the battery management system. What that figure means, why it can differ from measured capacity, and what a seller gains from it.
Checking Tesla Battery Health: Every Method Compared (2026)
In-car test, service mode, Tessie, Aviloo or Akkubrief: what each method costs, how long it takes, and what its result actually proves to a buyer.
Battery SoH Gets a Global Standard: What UN GTR 22 and Euro 7 Mean
For years SoH was a matter of definition — every measurement its own truth. Now, for the first time, there is a worldwide standard for how battery ageing is to be measured: UN Regulation GTR 22 with its State of Certified Energy metric. What lies behind it, what the science says about it, and why we align with it.
Battery Basics
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