Aviloo Study of 500,000 EVs Finds Most Batteries Retain 90% Capacity After 100,000 Miles
Large-scale diagnostics data debunks battery 'brick' myths while highlighting the longevity gap between liquid-cooled and air-cooled systems.
Most electric vehicle batteries remain remarkably healthy as they age, typically retaining over 90% of their original capacity after 100,000 miles. A comprehensive study by EV diagnostics firm Aviloo suggests that the fear of batteries suddenly failing or "turning into bricks" is largely unfounded for the majority of modern models.
Analyzing 500,000 battery health tests across 20 popular EV models between 2022 and 2026, Aviloo found that the Hyundai Ioniq 5 was a standout performer. The model led the study in battery health at both the 50,000 km milestone, where it maintained over 97% capacity, and the 100,000 km mark, where it stayed above 95%. As vehicles reached 150,000 km, the Mercedes-Benz EQA and Hyundai Ioniq 5 tied for the highest median capacity at 93.97% and 93.79%, respectively.
The Cooling Divide
The data reveals a stark contrast in degradation based on thermal management systems. Liquid-cooled batteries consistently outperformed air-cooled alternatives. The Nissan Leaf and Renault Zoe, both of which utilize air-cooling, showed significantly higher degradation. After 150,000 km, the Leaf's median health dropped to 86.67%, while the Zoe fell to 87.33%.
Tesla's popular offerings landed in the middle-to-bottom range of the study's high-mileage bracket. At the 150,000 km mark, the Tesla Model Y recorded a median health score of 90.3%, while the Model 3 trailed slightly at 88.94%.
Why It Matters
For used EV buyers and current owners, these findings provide a data-driven baseline for expected range loss. The study suggests that a 10% drop in range at 100,000 miles is a reasonable expectation for most drivers, reducing the perceived risk of long-term ownership.
Beyond mileage, the results underscore the technical superiority of liquid-cooling in preserving cell chemistry. However, hardware is not the only factor. An Aviloo representative noted that manufacturers use different battery chemistries with various trade-offs, meaning that even identical charging habits can produce very different results across different models.
What's Next
As the used EV market expands, the industry is likely to place a higher premium on vehicles with proven thermal management systems. While the general trend is positive, the impact of extreme climates and specific fast-charging habits remains a critical area for further analysis. Future data will likely focus on whether these degradation curves remain linear or accelerate as batteries pass the 200,000 km threshold.