🔋 EV Battery Degradation Calculator

The calculator uses average yearly capacity loss measured in real-world vehicles. In a January 2026 study of more than 22,700 EVs, Geotab found average degradation of 2.3% per year: around 1.5% per year for vehicles that mainly used AC or lower-power charging and up to 3.0% per year for vehicles relying heavily on DC fast charging above 100 kW. Vehicles in hot climates lost about 0.4% more per year.

Remaining capacity is estimated as 100% − (yearly loss × years). Many batteries lose slightly more in the first year or two and then level off, so long-term results are often a little better than a straight line.

The result is compared with the typical warranty threshold of 70% capacity within 8 years or 100,000 miles in the U.S.

How much battery capacity do EVs lose per year?

On average around 2–3% per year in recent real-world data, depending mainly on how often the car uses high-power DC fast charging and on climate.

When should an EV battery be replaced?

Most warranties cover a battery that falls below about 70% of its original capacity within 8 years or 100,000 miles in the U.S. Many batteries stay well above this level for much longer.

How can I slow down battery degradation?

Use AC charging for everyday needs, avoid leaving the car at 100% or near 0% for long periods, keep it cool in hot weather and follow the charging advice in your owner's manual.