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Battery knowledge for buying and selling used EVs: independent, with sources and free of sales pressure.
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the essentials in 22 minutesBattery SoH Value Explained: What the State of Health Tells You
The SoH value is the single most important number when buying a used EV — and the most misunderstood. What counts as good, where the figure deceives, and why it proves little without history.
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
4 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 2026Whoever Measures Has a Stake: What Makes a Battery Certificate IndependentNew
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.
Selling 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.
Testing & Measuring
3 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 2026Checking 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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