Updated electric vehicle (EV) battery health data from Geotab shows that modern EV batteries continue to perform strongly through their operational lifespan, even as fast charging becomes more common.

In its updated EV battery health study, Geotab analyzed real-world battery health data from more than 22,700 electric vehicles across 21 makes and models, drawing on several years of aggregated telematics information. The updated analysis shows an average annual battery degradation rate of 2.3%, compared to 1.8% in Geotab’s 2024 findings.

The increase reflects changes in how EVs are used, notably a growing reliance on high-power DC fast charging. EV lifespan can be a concern for both individual drivers and fleet operators, particularly as adoption accelerates across commercial and public-sector fleets. By understanding how batteries age under different charging, climate, and usage conditions, operators can better manage EV performance, protect battery health, and make more informed decisions about vehicle deployment and charging strategy throughout the vehicle's life.

“EV battery health remains strong, even as vehicles are charged faster and deployed more intensively,” said Charlotte Argue, senior manager of Sustainable Mobility at Geotab. “Our latest data shows that batteries are still lasting well beyond the replacement cycles most fleets plan for. What has changed is that charging behavior now plays a much bigger role in how quickly batteries age, giving operators an opportunity to manage long-term risk through smart charging strategies.”

Charging Power as a Dominant Factor

The analysis shows that charging power is now the strongest operational influence on EV battery health. Vehicles that relied heavily on DC fast charging above 100 kW experienced faster degradation, averaging up to 3.0% per year, compared with around 1.5% for vehicles that primarily used AC or lower-power charging.

Other factors, such as climate, showed a smaller independent effect. Vehicles operating in hotter regions degraded at a rate of around 0.4% per year faster than those in mild climates.

Strict Charging Rules Aren't as Critical

The data also challenge the need for strict day-to-day charging constraints. Vehicles that regularly used a wider state-of-charge range did not show higher degradation unless they spent prolonged, habitual periods near full or near empty charge levels.

Higher-use vehicles showed slightly faster degradation, increasing by around 0.8% per year compared to the lowest-use group, but this is an acceptable trade-off relative to the operational and cost benefits of keeping vehicles in service. For many fleets, these productivity gains directly translate into a lower cost per mile over the vehicle’s life.

“For fleets, the focus should be balance,” Argue added. “Using the lowest charging power that still meets operational needs can make a measurable difference to long-term battery health without limiting vehicle availability.”

EV Battery Degradation, Explained

Battery degradation is a natural process that reduces a battery's storage capacity over time.

Battery condition is measured as state of health (SOH). Batteries begin their life at 100% SOH and deteriorate gradually. For example, a 60-kWh battery operating at 80% SOH effectively behaves like a 48-kWh battery.

Geotab’s data shows that, while degradation rates vary by model, charging behavior, and usage patterns, the majority of modern EV batteries remain fit for purpose well beyond typical ownership and fleet-replacement timelines.

Pay Attention to EV Battery Data

Accurate state-of-health information, enabled by comprehensive telematics data, is key to helping people make the most of electric vehicles. Telematics data insights, available in Geotab’s EV Battery Health report, enable fleets to determine the true battery capacity of their EVs, understand degradation rates, and maximize value throughout their life cycle.