Scientists Discover Batteries Age Slower Than Previously Thought
Batteries of electric cars last much longer than previously thought, according to research from Stanford University in San Francisco. Another striking conclusion: strangely enough, batteries actually enjoy occasional hard acceleration.
Until recently, all studies on charging and discharging electric cars indicated that if you are careful with your battery, it will last the longest. So, not accelerating hard too often, using the supercharger along the highway as little as possible, and charging and discharging regularly and consistently. But that’s not true at all, it turns out.
The batteries of electric vehicles that are exposed to normal use by drivers in the real world – such as heavy traffic, long highway trips, short city trips, and primarily being parked – could last about a third longer than researchers have generally predicted. This is at least according to a study by scientists from the Stanford Battery Center.
‘Always Tested Wrong’
“We have never tested EV batteries the right way,” says Simona Onori, lead author and associate professor of energy science and engineering at the Stanford Doerr School of Sustainability. Almost always, battery scientists and engineers have tested the lifespan of new battery designs in laboratories using a constant discharge rate, followed by charging.
“To our surprise, the battery lasts longer than we thought based on industrial standard laboratory tests. Thanks to real driving with frequent acceleration, braking to recharge the batteries a bit, stopping to step into a store, and letting the batteries rest for hours, they appear to have a much longer lifespan,” said Onori.
‘Acceleration Peaks Actually Good’
According to the study published in Nature Energy on December 9, the more realistic the profiles reflected actual driving behavior, the higher the EV’s life expectancy became. Even more remarkable: the research showed a link between sharp, short accelerations and slower degradation.
“So stepping hard on the pedal does not speed up the aging process, but actually slows it down,” explained Alexis Geslin, one of the three lead authors of the study. This is contrary to the long-held assumptions of battery researchers that acceleration peaks are bad for EV batteries.
For car buyers, this could be good news. Battery life is a particular concern for people looking to buy a used electric car.