Interested in buying an EV but holding out because of questions about battery lifespan? Well, now, new research recently presented at the 245th National Meeting & Exposition of the American Chemical Society (ACS) can provide you with the answers that you’re looking for.
“The battery pack could be used during a quite reasonable period of time ranging from 5 to 20 years depending on many factors,” said Mikael G. Cugnet, Ph.D., who talked about the research at the ACS meeting. “That’s good news when you consider that some estimates put the average life expectancy of a new car at about eight years.”
According to Cugnet, the battery’s lifespan is dependent upon the temperature, state of charge, and the charge protocol. The performance of the battery declines much more strongly after the temperature reaches around 86 degrees Fahrenheit, for example. “The higher the temperature, the lower the battery service life. A temperature above 86 degrees F affects the battery pack performance instantly and even permanently if it lasts many months like in Middle East countries.”
Cugnet also recommends that electric vehicle (EV) owners be aware of how fully their batteries are charged — that’s another important factor in the battery’s longevity. He states that a fully charged battery is more susceptible to power loss at temperatures over 86 degrees F.
In order to test the limits of the currently used lithium-ion EV batteries, the researchers put the batteries through a reconstructed version of the experience that they typically go through, but while in the laboratory. “Using data gleaned from a real five-mile trip in an EV, they put EV battery packs and cells through simulated lifetimes of driving with cycles of draining and recharging. The researchers considered a battery to be beyond its useful lifespan when it had lost 20 percent of its full power.”
Knowing that an EV’s battery typically lasts an impressive 5-20 years, longer than most cars are owned, should provide some peace of mind to those considering the purchase of an EV. And will hopefully help to spur further EV growth.
Something worth noting is that even after their use in EVs, the batteries are still quite useful for other purposes. The researchers mention that many EV makers are currently working on what are known as second life uses for the batteries, after they’ve lost enough charge to be considered worth replacing in EVs. Such uses include: as backup power sources for computers and medical equipment; and as electrical grid storage, for use with intermittent power sources such as solar photovoltaics. Many manufacturers are also currently working to develop recycling programs that will allow the reuse of many of a battery’s components.