How long will the battery on your electric vehicle last?

Typical battery wear

The vast majority of electric vehicle (EV) traction batteries from major automakers come with an eight-year/160,000-kilometre warranty. Since these batteries—and the engines they power—have fewer mechanical components than an internal combustion engine, they are less likely to break down and need replacing.

But that doesn’t mean EV batteries will last forever. Over time and use, their initial capacity decreases slightly, notes Martin Archambault, spokesperson for the Association des véhicules électriques du Québec (AVEQ). “Capacity loss varies, but it is almost always less than 2 to 3% per year,” he says. “The biggest threat to EV batteries is heat. That’s why manufacturers are doing more and more to protect them from heat. The latest batteries are generally better insulated and cooled.”

So as it ages you should expect your battery to lose some run time. How much may vary by make, vehicle, usage, and other factors. In fact, the first buyers of Tesla and Nissan e-cars found that the manufacturer’s predictions were often more pessimistic than their actual results.

Replacing the battery: Manufacturer’s warranties can be clear as mud 

It’s not always easy to make heads or tails of warranties on new electric vehicles. Since faulty batteries are relatively rare, few people have had to go through the process of replacing this essential EV component. Automakers prefer not to bind themselves with overly restrictive replacement warranties, notes CAA-Quebec. 

“If your traction battery needs to be replaced, do you install a new battery or a used or reconditioned one? And at what percent of its original capacity is it considered defective?” asks Pierre-Serge Labbé, Vice President of Automotive Services at CAA-Quebec. “This is key because the battery’s capacity is what dictates an EV’s value. You can’t leave that decision to the manufacturer. Current and future owners need to know what to expect,” he says.

Surprisingly, Labbé points out that it’s luxury carmakers that actually have the most nebulous warranties. Makers like Kia and Hyundai already have generous warranties on their fuel-operated vehicles to attract buyers, and now they’re adopting the same approach for the EV sector. And along with American manufacturers, Nissan, and Tesla, they’re the only ones who clearly set out the minimum capacity for a replacement battery. Makers like Audi, BMW, and Mercedes-Benz are more restrictive, with more limitations on coverage for the electric motor and other components.

Clearing up questions about electric vehicles and car warranties

To help you make sense of it all, CAA-Quebec has posted a comprehensive guide to new-vehicle warranties for model year 2019, which includes EV warranties. This guide can be an invaluable tool to help new car shoppers avoid any unpleasant surprises after a few years, even with an electric vehicle.

Got more questions about your EV? Ask the experts at CAA-Quebec Mobility Advisory Services.