Battery degradation has long been one of the main reasons new car buyers have hesitated to purchase an electric vehicle. However, data from a new study, described as the largest independent analysis of used EV batteries ever conducted, reveals that the top-performing models lose less than 5 percent of their range after 93,205 miles (150,000 km) of driving. The findings suggest that modern battery packs will comfortably outlast the average lifespan of most new cars.
The study, published by the Austrian battery analytics company Aviloo, is based on more than 500,000 individual battery tests and covers 20 of the industry’s most popular electric models. After 93,205 miles on the road, the Mercedes-Benz CLA emerged as the outright leader, retaining 94 percent of its original usable capacity. It finished ahead of the Hyundai Ioniq 5, which retained 93.6 percent, the Hyundai Kona EV at 93 percent, and the Volvo XC40 Recharge at 92.8 percent. The Ford Mustang Mach-E and the Polestar 2 both retained 92.5 percent of their capacity.
The results are particularly striking for Tesla, a brand often associated with class-leading battery technology. The Tesla Model Y retained just 90.3 percent of its battery capacity after the same distance, while the Tesla Model 3 fared worse, holding onto only 88.9 percent. Both figures place the American manufacturer firmly in the lower half of the rankings. Other weak performers included the Renault Zoe at 87.3 percent, the Mini Cooper SE at 87.1 percent, and the Nissan Leaf at 86.7 percent, all of which are models equipped with relatively small battery packs.
Aviloo’s data also highlights how different models degrade at different rates over time. At the 31,068-mile (50,000 km) mark, the Hyundai Ioniq 5 was the best performer, retaining 97.1 percent of its capacity, followed by the Mercedes-Benz CLA at 96.6 percent and the Hyundai Kona EV at 96.3 percent. The Audi Q8 e-tron retained 95.7 percent, the BMW i4 95.6 percent, and both the Volvo XC40 Recharge and VW ID.4 held onto 95.2 percent. By the time the vehicles reached 62,000 miles (100,000 km), the Mercedes-Benz EQA had taken the lead with 95 percent retention, with the Ioniq 5 and BMW i4 close behind at 95.3 and 94.3 percent respectively.
The study’s authors caution that the figures represent median values across all tested vehicles, not a guarantee for any individual car. Battery health ratings for the same model can vary by as much as 13.5 percent between good and bad examples, meaning that driving style, charging habits, and climate all play a significant role in long-term degradation. Nevertheless, the overall picture is encouraging for EV adoption. Even the weakest performers in the study, such as the Nissan Leaf, retained more than 86 percent of their capacity after 93,205 miles, which is still sufficient for the daily driving needs of most motorists.
For buyers concerned about the longevity of electric powertrains, the study offers a clear takeaway: the technology has matured to the point where battery packs are no longer the weak link in an EV’s lifespan. The gap between the best and worst performers, however, shows that not all batteries are created equal, and that model choice remains an important factor for those planning to keep their car for the long haul.