How long do electric vehicle batteries actually last?

"As the fleet of EVs on the road ages, new data pooled from tens of thousands of vehicles is showing those batteries are lasting longer than expected. Batteries come with warranties, but they don't last as long as the car. If a high-voltage battery chokes out midway through a car's life, it needs replacing at a price tag that can run in the ballpark of $5,000 to $20,000."

"Lithium-ion batteries undergo two kinds of aging. First, there's calendar aging: They degrade as time goes on, holding less juice, even if they just sit in storage. Then there's cyclical aging, which is how much a battery degrades based on its use being charged and discharged, over and over again. That means there's no way to dodge degradation."

"Recurrent, a research firm that pulls in data from over 30,000 EV drivers, describes it as an 'S curve.' There's a rapid decline at the beginning, a long leveling off, and then a more rapid decline at the end. 'It's very much like breaking in a pair of shoes,' says Liz Najman, the director of market insights at Recurrent."

Early predictions about electric vehicle battery lifespan were pessimistic, with 2010 estimates suggesting only seven years of usable life. This created buyer hesitation since replacement costs range from $5,000 to $20,000 and batteries typically outlast warranty periods. However, accumulated data from over 30,000 EV drivers reveals batteries are degrading more slowly than expected. Battery degradation occurs through two mechanisms: calendar aging, which happens over time regardless of use, and cyclical aging from repeated charging and discharging. The degradation pattern follows an S-curve with rapid initial decline, extended stability, then accelerated decline later, similar to breaking in new shoes.

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