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When it comes to buying an electric car, especially a used one, long-term battery health can be an important consideration. A study by Swedish used-car marketplace Carla analyzed the results of 9,954 electric vehicle (EV) battery tests run between 2022 and 2026 to identify the EV models that retain the most battery capacity after about 62,000 miles (100,000 kilometers). To ensure a fair comparison, Carla only included models with a substantial number of battery tests using technology developed by AVILOO, a company specializing in independent EV battery diagnostics.

After analyzing the data, Kia and Hyundai — both part of South Korea's Hyundai Motor Group — emerged as the brands whose models retained the most battery capacity over time. The Kia e-Niro came out on top, retaining 97.25% of its reported battery health after 62,000 miles on the road, with the Hyundai Kona following closely at 97.18%. Another Kia car, the EV6, placed third at 95.95%.…