The takeaway: As electric vehicles become more popular, owners are discovering that modern EV batteries are surprisingly durable, lasting far longer than commonly believed. A new study now finds that these batteries continue to perform consistently throughout their operational life, even with frequent use of DC fast charging.
According to data published by GeoTab, the average annual battery degradation rate for EVs is only around 2.3 percent – much lower than most car owners expect. Degradation depends on several factors, with the most important being how frequently the vehicle is charged using high-power DC fast charging above 100 kW.
Mileage also directly affects battery health, as vehicles that undergo more charge cycles experience greater degradation than those that are used less frequently. The study found that EVs charged less than once a week show an average degradation of about 1.5 percent per year, while batteries charged every couple of days degrade around 2.3 percent annually.
Climate can also influence long-term battery health, with very hot weather reportedly accelerating degradation by approximately 0.4 percent. However, charging power and frequency remain the dominant factors affecting battery longevity.
The study also examined the effects of charging to 100 percent and discharging to zero. While most automotive and consumer electronics companies caution against fully charging or fully depleting devices that use lithium-ion or lithium-carbon batteries, the data suggests that, in the case of EVs, these extremes have minimal impact in real-world usage.
However, leaving an EV at either 100 percent or zero percent charge for extended periods can negatively affect battery health. The study found that if an EV spends 80 percent of its time in either of these extreme states of charge, the battery degrades about 0.5 percent faster.
The analysis covered more than 22,700 EVs in 2025, spanning 21 different models across several major brands. While results were largely consistent within vehicle categories, there were notable variations depending on operating conditions, battery chemistry, and vehicle size.
For instance, multi-purpose vehicles, including light vans, averaged a higher degradation rate of 2.7 percent per year, compared with light passenger cars – such as sedans and SUVs – which exhibited an average decline of around 2.0 percent per year. Energy density and battery management configurations also reportedly influence battery longevity.