Monthly Myth: Your EV battery must be replaced in 5 to 10 years
Take a look at the truth
BY TIM BENFORD: PRESIDENT OF DRIVE ELECTRIC DAYTON, PAST VICE-PRESIDENT OF ELECTRIC AUTO ASSOCIATION
Data gleaned from multiple Tesla owners has shown a mere 10% average battery degradation after over 160,000 miles.
The battery in your electric car will last beyond its eight-year warranty. But given all the rampant battery life myths, how would you know that? Let’s look at the facts.
At the heart of every vehicle is an energy source to drive the wheels. For internal combustion engines (ICE), it’s a tank of gas that burns to release required energy. For an electric vehicle (EV), it’s a battery charged with electrons that provides energy to an electric motor.
The myth
A gas tank is a hardy component that can be tricky to replace but is not terribly expensive. An EV battery is a large and complex subsystem formed to the underside of the vehicle in a skateboard-like configuration. Unlike gas tanks, batteries make up approximately 40 percent of the value of an electric car.
Therefore, prospective EV buyers are often concerned about the complexity, life span, and replacement cost of the battery. They hear it needs to be replaced in five to 10 years, but that’s just not true. Let’s myth-bust this one-by-one.
EVs aren’t like phones
Most people who have experience with smartphones are aware that lithium-ion (Li-ion) batteries lose their capacity to hold charge over time. These folks worry that an EV’s battery will behave in the same way. However unlike a smartphone, an EV battery consists of multiple AA-battery-like containers that in most cases are supported by a Battery Management System. It automatically keeps the battery at an optimum temperature for a long life, at 70 degrees, where humans too are at their happiest.
An EV’s battery’s life can be maintained when it is not always charged to 100% and is not sitting empty for long. Most EVs have a user interface that informs the owner of the battery’s charge level. Keeping an eye on the battery’s health is a simple routine behavior for an EV owner.
EVs smart charge
Smartphone batteries are charged every day and degrade considerably after a few years. The average EV driver charges an EV just a few times per month. EVs also charge in a much smarter fashion, replenishing just depleted cells. This distributes the load across many thousands of cells that make up the whole battery.
Data gleaned from multiple Tesla owners has shown a mere 10% average battery degradation after over 160,000 miles. Most ICE cars are on the scrap heap long before they complete such mileage. Indeed, most people only keep their vehicles for approximately six years.
Cleaner sourcing extends use
More and more batteries are now manufactured from metals other than cobalt. These new metals not only last longer in batteries, they also address anxiety that prospective EV shoppers have had about the use of child labor in the cobalt mining process. In fact, the EV industry is more responsibly-sourced of late, and has a higher percentage of recycled components. The 2018 Tesla Model 3 battery consists of 2.9% cobalt. It is predicted that cobalt-free batteries could reach the market by 2025.
Interestingly, most plug-in vehicle makers are working with other battery types (such as lithium-iron-phosphate and lithium-manganese) which have inherent safety advantages and provide more years of service.
Used batteries see a second life
Another favorite anti-EV argument is that recycling Li-ion batteries is difficult, expensive or even flat-out impossible. However that is not the case. Recycling International reports that some 97,000 tons of Li-ion batteries were recycled in 2018, and over 1 GWh worth are currently serving in second-life applications.
500% less likely to catch fire
Finally, when news of an EV battery fire hits the headlines, fears are raised in the minds of buyers. To put the risk in perspective, UK data from 2019 obtained by Air Quality News revealed that the London Fire Brigade dealt with just 54 EV fires compared to 1,898 petrol and diesel fires.
Similarly, so far in 2020, London fire services have dealt with 1,021 petrol and diesel fires and just 27 EV fires.
As Elon Musk himself tweeted: “Teslas, like most electric cars, are over 500% less likely to catch fire than combustion engine cars, which carry massive amounts of highly flammable fuels.”
90% after 200k miles
Tesla's 2019 impact report showed that the majority of Model S and X cars had more than 90% battery life after 200,000 miles of driving.
Not surprisingly, the majority of manufacturers are so confident in the durability of their EV batteries that they offer a battery warranty that’s usually 100,000 miles or eight years for 70% capacity. At the recent European Conference on Batteries, Elon Musk reported that batteries under development will give EVs 620 miles of range and a 15-year life. He also announced advances that will allow Tesla to slash battery manufacturing costs, speeding a global shift to renewable energy.
Conclusion
The facts show that EV batteries are very durable and warrantied for approximately eight years. Although range will degrade slightly over time, the battery will not need replacement for at least eight years, and will likely be totally acceptable for normal use far beyond that. Concerns about battery life should not dissuade potential buyers from purchasing an EV.
However, when they do get over this battery myth, these buyers may assume there are limited EV models to choose from. Next month we’ll take a crack at that myth.