EV Battery Health: Fast Charging Accelerates Degradation

New research indicates that frequent use of high-power DC fast chargers can accelerate electric vehicle (EV) battery degradation by up to 100% compared to slower charging methods. On average, EV batteries lose slightly over 2% of their capacity each year. However, a study analyzing data from over 22,700 EVs found that predominantly using fast chargers can result in an annual degradation rate of 3%, whereas slow charging leads to only 1.5% loss.

This trend is observed as countries expand rapid charging networks, offering quicker replenishment for EV owners. Battery degradation is a natural process, but charging behavior now presents a significant factor in battery aging. While EV batteries generally maintain strong health beyond typical fleet replacement cycles, owners can optimize performance and longevity by adopting smart charging strategies. For instance, EVs consistently using over 12% DC fast charging experienced an increased average annual degradation of 2.5%.

Contrastingly, vehicles primarily using lower-power charging are projected to retain 88% of their original battery capacity after eight years, with a 1.5% annual degradation. Conversely, those frequently employing high-power DC fast charging may only retain 76% capacity after the same period, exhibiting a 3% annual degradation. While climate also affects degradation, its impact is minimal compared to charging habits, suggesting controlled charging is key to battery preservation.