There is no single expiry date for an electric car battery. Age, use, temperature, charging habits and battery design all matter. Many batteries remain useful for years, but the condition of the individual car is more valuable than a general claim.
What battery health means
State of health compares current usable capacity with an original reference. Different assessment methods can give different results. Ask who measured it, when, and what the report actually establishes.
What to check
Look for charging faults, unusually inconsistent range and evidence of repairs. Ask for warranty documents and a VIN-specific check. Manufacturer capacity protection usually has age, mileage and minimum-capacity conditions.
How to assess battery health
Ask whether a state-of-health report exists, which tool or method produced it and when it was run. Diagnostic reports read from the car’s battery management system are more informative than a dashboard range estimate. A test drive and a full charge can reveal obvious issues but do not replace a proper assessment. If no report is available, First EV will say so: Battery health assessment not yet available.
Avoid assumptions
Neither a low mileage nor a full-charge dashboard reading proves battery condition. Build a sensible range buffer around your needs and ask for evidence before purchase.