EV battery health & degradation: what every buyer should know
How lithium-ion packs age, what typical degradation looks like over eight years, and the charging habits that make the biggest difference.
Battery degradation is the concern that stops most people buying an electric car, and it is the one the data has treated most kindly. Packs do lose capacity, but far more slowly than early fears suggested, and the pattern is now well documented across large fleets.
This guide is a placeholder outline while we finish our full breakdown. The sections below cover what the finished article will explain in detail.
How much capacity cars actually lose
Large fleet studies put typical degradation at roughly one to two percent a year, with a steeper drop in the first months and a long, slow decline afterwards. Outright pack failure outside warranty remains rare.
- Most loss happens early, then the curve flattens
- Wide variation between individual cars and climates
- Chemistry matters: LFP packs behave differently from NMC
What accelerates degradation
Heat, time at very high or very low states of charge, and heavy reliance on DC fast charging are the main factors within a driver's control.
- Routinely charging to 100% and leaving it there
- Frequent DC fast charging as the primary method
- Sustained high ambient temperatures without active cooling
Habits that help
Day-to-day charging to around 80%, topping up to 100% only before long trips, and using slower AC charging where possible all extend pack life. LFP cars are an exception and generally want a periodic full charge.
Warranties and second life
Battery warranties commonly run to eight years or 100,000 miles with a guaranteed minimum capacity. Packs that fall below usable automotive capacity still have value in stationary storage.
Detailed degradation data by model is coming soon.
Put this guide to work
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