A recent study indicates that electric vehicle (EV) batteries retain more capacity over time than many drivers expect, suggesting that concerns about long-term battery durability may be overstated. The research, conducted by Avilio, an Austria-based battery health analysis group, reveals that most used EVs maintain approximately 90 percent of their original usable battery capacity after traveling 150,000 kilometers.

The study assessed half a million battery health tests conducted globally between 2022 and 2026 across 20 popular EV models, including Tesla’s Model Y and Volkswagen’s ID.4. Avilio found the median state of health (SoH) — a measure of remaining battery capacity relative to its original — ranged from 87 to 94 percent after 150,000 kilometers. At earlier mileage intervals, the median SoH was higher, between 91 and 97 percent after 50,000 kilometers, and between 88 and 95 percent after 100,000 kilometers.

Battery warranty coverage for EVs typically spans eight years or 160,000 kilometers (100,000 miles), with manufacturers obligated to replace batteries if capacity drops below 70 percent. The findings suggest that most EV batteries remain well above that threshold by the time warranties expire.

Avilio’s analysis also noted significant variation in battery degradation even within the same model, influenced by factors such as climate, battery size, and driver behavior. For example, Nissan’s Leaf ZE1, which has a smaller battery necessitating more frequent charging, exhibited the largest variation in SoH at 150,000 kilometers—up to 13.5 percentage points—equating to roughly 29 kilometers in driving range per charge. Tesla’s Model Y showed an SoH spread of up to 11 percentage points, Volkswagen’s ID.4 between 11 and 12 points, and Hyundai’s Ioniq 5 more than 12 points.

Marcus Berger, CEO of Avilio, highlighted the impact of environmental conditions and charging habits on battery health. He pointed to faster degradation in hotter climates and advised owners against leaving batteries fully charged while parked, recommending an ideal charge level between 30 and 70 percent to preserve battery life.

The study did not include Chinese EV models due to insufficient data.

In the UK, the findings come amid calls from major EV organizations for the government to introduce mandatory battery health certifications. Proponents argue such measures would bolster consumer confidence and improve transparency in the used EV market. James Strong, used-car sales and delivery manager at Tesla UK, said there is growing demand for reliable battery health information. He stated that a nationally recognized standard for battery SoH would help reassure buyers and reward owners who properly maintain their vehicles.