The seller can get you this data for free

Dealers rarely show a real state-of-health figure. But under the EU Data Act any owner can request their vehicle's data export free of charge from the Volkswagen Group portal. So:

1. Ask the seller early to request the historical data package for the car and send you the file — it costs them a few clicks and a few days' wait, and covers roughly the last two months of driving.
2. Drop the file into this tool. You get an independent report:
   • Measured usable battery capacity, when the export includes diagnostic history — integrated from actual charging sessions and matched against the pack sizes that model shipped with (a pack measuring 80 kWh can only be a degraded 86, never a healthy 77 — the tool reasons accordingly), with a session-by-session table showing exactly how each measurement was made.
   • Cell imbalance — an early-warning indicator no test drive or range test will show, broken down by state of charge and load.
   • Odometer cross-check — the diagnostic odometer channel against the reported mileage field, a basic tampering sanity check.
   • How the battery was treated — DC fast-charge share, charges past 80%, deep discharges, idle drain, and whether the car spent its parked nights conditioning the pack.
3. A seller who refuses to share a free, privacy-redacted export about the car they're selling is also telling you something.

The reference export contained no location data, and the dashboard redacts the VIN and account identifiers by default. The result still contains detailed vehicle history, so sellers should review it and share it deliberately.

Best supported: the MEB platform family — VW ID.3/ID.4/ID.5/ID.7/ID. Buzz, Cupra Born/Tavascan, Škoda Enyaq/Elroq, Audi Q4 e-tron — which share the same 96-series battery packs. Other Volkswagen Group vehicles still get the documented fields, ledgers and the package audit.