Most EV Batteries Retain Over 90% Capacity After 93,000 Miles, Study Finds

Electric vehicle batteries are proving far more resilient than public perception suggests, with the vast majority maintaining high capacity well into their lifespans. A comprehensive independent study has found that most EV batteries retain over 90% of their original usable capacity after 150,000 kilometers (approximately 93,000 miles).

The research, conducted by Austrian diagnostics firm AVILOO, analyzed more than 500,000 battery tests across 20 popular EV models. The data reveals that top-performing vehicles lose very little of their range over this distance. Specifically, the Mercedes-Benz EQA led the group with a median State of Health (SoH) of 94% at the 150,000 km mark. It was followed closely by the Hyundai IONIQ 5 at 93.8% and the BMW i4 at 93.6%.

A New Standard for Measurement

Battery degradation has long been a primary deterrent for potential EV buyers, often fueled by anecdotal evidence or inconsistent manufacturer data. To get an accurate picture, AVILOO utilized its proprietary FLASH Test. This method involves a three-minute diagnostic via the vehicle's OBD port using a statistical model trained on real-world data. By bypassing the vehicle's own Battery Management System (BMS), which varies significantly between manufacturers, the study provided a standardized benchmark for comparison across different brands.

Market Implications and Performance Gaps

These findings provide critical empirical evidence that could stabilize and increase confidence in the used EV market. When batteries do not wear out as quickly as feared, the residual value of second-hand electric cars becomes more predictable. However, the study also highlighted a performance gap between models. The Tesla Model 3, for instance, recorded a median SoH of 88.9% at 150,000 km, placing it in the bottom third of the studied models.

Analysts noted a correlation between battery size and the rate of decline. Smaller battery packs, such as those found in the Mini Cooper SE and Nissan Leaf, showed faster degradation. This is largely attributed to more frequent charging cycles required to cover the same distance as vehicles with larger packs.

The Road Ahead

As the industry moves toward longer-range batteries and more efficient thermal management, the data suggests that the battery pack is unlikely to be the limiting factor in a vehicle's lifespan. The best packs in the study remain north of 93% health after 93,000 miles, suggesting these batteries are not wearing out at a rate that should alarm consumers. Future monitoring will likely focus on whether these trends hold as vehicles surpass the 300,000 km threshold.