Swedish study finds EV batteries retain over 90% capacity, debunking common degradation myths
Published on Nov 09, 2025 at 11:11 PM (UTC+4)
by Henry Kelsall
Last updated on Nov 07, 2025 at 7:46 PM (UTC+4)
Edited by
Amelia Jean Hershman-Jones
A Swedish study has managed to debunk the theory that EV batteries degrade massively and lose capacity over time.
One of the big worries for first-time electric car buyers is how much the batteries degrade over time, and how much capacity for overall range they can retain.
A study in Sweden by the used-car marketplace, Kvdbil, has analysed the ‘state of health’ of over 1,300 used EVs as well as plug-in hybrids to find out what happens.
As the study showed, it turns out that EVs can retain nearly all of their original battery technology over a few years.
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EV batteries retain more capacity than you think
According to Kvdbil, the study was overwhelmingly positive regarding the health of EV batteries.
They found that eight out of 10 used electric cars would retain more than 90 percent of their battery capacity.
That is far better than critics and customers have claimed and feared would be the case.
At the top of the study were the Kia EV6 and e-Niro, as well as the Tesla Model Y.
The Model Y still remains one of the most popular electric vehicles in the world.
Potential EV customers will likely be happy to hear the findings of the study.
Buyers could easily expect years of reliable service and charge from an electric car.
Battery degradation occurs slowly in an EV
Martin Reinholdsson, test manager at Kvdbil, spoke about how quickly electric cars can drain.
He said: “The degradation of a car battery occurs slowly thanks to advanced technology and smart design, including cooling of the battery cells.”
This, he also said, confirmed the myth that used car batteries ‘wouldn’t last long.’
In fact, it is now possible that they might begin to outlast the cars they are in.
Longer-life batteries are also good news for the environment.
It could, in theory, mean fewer batteries end up in landfills or need to be recycled.
Batteries being recycled will also mean fewer minerals need to be mined from the earth.
That is one of the most damaging processes involved in EV manufacturing.
So, for those worrying about degradation, it looks like you don’t need to worry anymore.
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Henry is a content writer with nearly ten years experience, having written for various publications since 2017. Qualifying with a Sports Journalism degree from Staffordshire University, Henry loves all things automotive but has a particular soft spot for classic Japanese cars and anything Lancia. He also has a curious passion for steam locomotives.
