Which EVs Have Longest Battery Life?

Wed 10th Aug 2022

While many motorists are at the very early stages of their EV journey, they only need worry about range and access to charging points. But for the more mature EV owner, there is the looming prospect that over time, the performance of the car’s battery will begin to degrade.

Like most things in motoring, not all cars perform the same on that scale, and now analysis has been done to tell us which cars have the longest battery life.

The research, which has been conducted by Canadian Fleet Management company Geotab, has studied the battery degradation data of some 6,300 pure electric and plug-in hybrid vehicles since 2014. The analysis found that the average battery retained 93.9% of its performance after three years, and 87.9% of its performance after six years. However, the analysis shows that battery loss tends to plateau after an initial early dip and then only begins fast degradation after 10-12 years.

According to the University of Birmingham, there are a range of conditions which can help retain the performance of your battery. Dr Gavin Harper, a critical materials fellow said: “It’s not just the number of charge-to-discharge cycles that a Lithium-Ion battery goes through that will cause degradation, but also the degree to which that battery is cycled. 

“Slow charging prolongs battery life, but rapid charging will cause faster degradation. Temperature control is also important. While colder temperatures will temporarily affect battery capacity, causing them to produce less power, batteries regain their function when they warm up. More long-term damage is done by having Lithium-Ion batteries at too high a temperature.”

So what are the top performing cars of the Geotab research? The 2017 Kia Soul EV retains 98.8% State of Health (SOH) after two years and eight months, the 2014 Renault Kangoo ZE has 97.5% after three years and the 2017 VW e-Golf has 96.9% after two years and eight months. To give some perspective, the worst performing car the 2018 Mitsubishi Outlander has 86.7% SOH after one year and eight months.