Massive test result compilation reveals which electric vehicles have healthiest batteries

Swedish used-car marketplace Kvdbil has made a new compilation of which used electric (EV) and plug-in hybrid (PHEV) vehicles have the healthiest batteries. Kia is best in class, but both Volvo and Tesla are on the top list. The compilation also shows that the batteries in electric and plug-in hybrids last significantly longer than many people think.

For the first time, Kvdbil has collected data from plug-in cars that have undergone the company's battery tests. The results – with tests from more than 1,300 cars – provide new insight into which car brands deliver the best battery health over time.

Kia stands out in the compilation; several of their car batteries show very high levels of State of Health (SoH). The South Korean brand tops both the EV list and the PHEV list with its cars. Volvo has one model among the EVs and two among the PHEVs. Tesla's Model Y is at the top among the EVs.

Eight out of ten cars receive top marks

Despite some differences between different brands, the overall picture is positive: Eight out of ten (79%) cars in the review received the highest rating in Kvdbil's three-star system, which means an SoH of more than 90%.

“The degradation of a car battery occurs slowly thanks to advanced technology and smart design, including cooling the battery cells. This is also evident in this result, which busts the myth that used car batteries do not last long. Even after a few years of use, most rechargeable batteries still have a lot left to give, something that drivers can increase further with good charging patterns,” says Martin Reinholdsson, test manager at Kvdbil.

Good for the environment – ​​and your wallet

The fact that the batteries in rechargeable cars stay in such good condition for such a long time means that buyers can feel confident in buying a used electric vehicle. Rechargeable cars are not only a sustainable choice for the environment – ​​but also a smart long-term investment for the wallet.

“Our tests show that the cars lose very little range over time, but with that said, you should not rely entirely on the car manufacturers' own WLTP data,” Reinholdsson says. “For those who want to buy a used electric car, this is a clear signal: You are getting a car that delivers performance and mileage that will last in the long run.”

The car brands with the best used battery (highest average rating for SoH based on just over 1,300 tests):

1. Kia
2. Audi
3. Opel
4. Tesla
5. Mercedes
6. Peugeot
7. Volvo
8. BMW
9. Volkswagen
10. Skoda

The electric cars with the best used battery:

1. Kia EV6
2. Kia e-Niro
3. Tesla Model Y
4. Opel Mokka-e
5. Mazda MX-30
6. Audi Q4 e-tron
7. Fiat 500e
8. Volvo XC40 Recharge
9. Citroen e-C4
10. Volkswagen ID 4

The plug-in hybrids with the best used battery:

1. Kia Sportage
2. Kia Optima
3. Volvo XC60
4. Kia Ceed
5. Volvo V60
6. Peugeot 3008
7. BMW 530e
8. Volkswagen Passat GTE
9. BMW X1
10. BMW 330e

Martin Reinholdsson's five tips on how to best take care of your car battery:

“Don't charge your battery fully often. Try to keep the battery's charge between 20% and 80% during everyday life and save a 100% charge for just before longer trips. Avoid extreme heat and cold. Protect your battery from extreme temperatures by parking it cool when it's hot, preheating the car when it's plugged in in the cold and using any battery preconditioning. Fast charge rarely. Use fast charging when needed but not all the time; avoid fast charging an ice-cold battery and top up with the charger at home before leaving. Don't leave your car fully charged. Don't leave your car parked for long near 0 or 100%, and if it's going to be parked for more than two weeks, leave it around 40% to 60% and turn off energy-intensive functions. Set a charge limit. Take advantage of your car's software support by setting a charge limit (for example, 80%), scheduling charging so that it's ready close to departure, and keeping the software updated.”

About the survey

The statistics are based on Kvdbil's review of battery health in 1,366 used electric and plug-in hybrid cars (723 electric cars and 643 plug-in hybrids) that have passed through the company's platform.