The Hyundai Ioniq 5 has emerged as the electric vehicle with the longest-lasting battery, according to a comprehensive global study analyzing battery health across more than 500,000 vehicles. The study, conducted by Austrian EV battery diagnostic firm AVILOO, assessed 20 popular EV models over a four-year period from 2022 to 2026, examining battery State of Health (SoH) data from tests performed in North and South America, Europe, Asia, and Australia.
The SoH rating indicates the remaining capacity of an EV's battery compared to its original maximum capacity. A 90% SoH, for instance, means the battery retains 90% of its original range. Encouragingly, none of the 20 models tested exhibited a median SoH drop exceeding 10% within the first 50,000 kilometers (approximately 31,000 miles).
The Hyundai Ioniq 5 achieved the highest median SoH of 97.13%. Following closely in second place was the Mercedes EQA with a median SoH of 96.56%. The Hyundai Kona secured third place with a median SoH of 96.27%.
Other notable models in the top ten include the Audi Q8 e-tron (fourth, 95.71%), BMW i4 (fifth, 95.60%), and Volkswagen ID.4 (sixth, 95.24%). The top ten was rounded out by the Volvo XC40 Recharge (seventh, 95.15%), Skoda Enyaq (eighth, 95.14%), Ford Mustang Mach-E (ninth, 95.09%), and Audi Q4 e-tron (tenth, 95.04%).
Battery Degradation Factors
The study found that EVs with smaller battery packs tend to show greater degradation, primarily because they require more frequent charging cycles. The Nissan Leaf (ZE1) and Renault Zoe, both featuring relatively smaller batteries, recorded the highest degradation levels among the top 20, with SoH scores of 91.23% and 91.64% respectively. Each charging cycle contributes to gradual wear, reducing overall battery capacity over time.
Conversely, vehicles equipped with batteries larger than 80kWh, such as the Hyundai Ioniq 5, generally achieved higher median SoH scores. The Ioniq 5, with its large battery, recorded a 97.13% median SoH at 50,000 km. While battery size is a significant factor, the study also noted exceptions, like the Tesla Model Y, which showed relatively lower performance compared to other large-battery EVs.
Variability in Battery Health
AVILOO CEO Marcus Berger highlighted that battery performance can vary significantly not only between different EV models but also between individual vehicles of the same model. "A gap of 10 or 15 per cent in state of health is a real difference in range, in what a car is worth, and in what you can rely on it for," Berger stated. He emphasized that independent testing is crucial for owners to understand their specific vehicle's battery health.
