Geotab recently published a real-world analysis of electric vehicle (EV) battery degradation based on telematics data from over 22,700 EVs spanning 21 different models, finding that modern EV batteries continue to perform robustly across typical vehicle lifespans.
The study, led by Senior Manager of Sustainable Mobility Charlotte Argue, reports an average annual battery degradation rate of 2.3 %, indicating that EV batteries generally retain a significant portion of their original capacity over time.
Key Findings from the Geotab Analysis
- Robust overall battery health: The updated dataset confirms that modern EV batteries are “built to last beyond a typical vehicle’s service life,” underscoring their durability in real-world conditions.
- Average degradation rate: The analysis found a 2.3 % annual degradation rate across the large sample, with projected capacity retention of approximately 81.6 % after eight years.
- Impact of charging power: High-power DC fast charging (above 100 kW) emerged as a significant stressor on battery health, contributing to higher degradation compared to lower-power charging conditions.
- Climate effects: Vehicles operating in hotter climates showed moderately higher degradation, with hotter conditions imposing a 0.4 % per year penalty compared to milder climates.
- Utilization trade-offs: Higher daily vehicle use was associated with measurable increases in battery degradation but was described as a trade-off that can be acceptable for fleet productivity and return on investment.
- State of charge observations: The study noted that battery degradation accelerates only when vehicles spend over 80 % of their time at or near full or near-empty charge levels.
Geotab’s findings provide updated, large-scale evidence of how EV batteries age under current usage patterns. The company stresses the influence of charging practices, climate conditions, and vehicle utilization on battery longevity, offering data to inform both fleet strategies and individual EV ownership decisions.
