The world’s only getting hotter, and you may have heard that temperature affects your battery. So if you leave your car parked out in the hot sun, is it possible that by the time you come back, the battery will be flat? Should you keep your jump cables handy every time there’s a heat wave – whether or not you have a charger?
The good news is that heat doesn’t do anything to your car battery’s actual charge, so there’s no risk of it going flat and needing to be jumped. The bad news is that sustained high temperatures will slowly damage the battery over time, shortening its lifespan. So while you won’t notice an effect on any given day, you may find that you need to buy an entirely new battery after only a few years, when it should have lasted a few years more. Even if your battery finally dies on a cold winter day, the culprit might well have been the last few summers.
What does hot weather do to a car battery?
Inside a battery are liquid chemicals that hold and, under the right conditions, release electrical charge. Heat, though, has a nasty habit of making liquids less, well, liquid. As the temperature causes evaporation, the newly released gases can cause corrosion to the battery’s body and lead plates. This might only be by a small amount on any one day, but over time, it adds up to damage. In turn, that damage will bring the battery’s end date closer. Evaporation will also weaken the chemicals’ ability to hold charge over time.
For this reason, car batteries parked in colder climates tend to last much longer than those parked in hotter ones. AAA estimates that the difference is worth about two years of lifespan, which is a sizeable percentage of any battery’s expected life. If you’re able, keep your car parked in cool, shaded locations, preferably a garage. Even a tree would be better than open sky. Of course, making sure you are buying the best car batteries will also help.
What does hot weather do to EVs?
Batteries are always important, but they are especially important for electric vehicles, since they’re what make them move. Everything said above applies to EVs as well, but in addition, higher temperatures actually affect the travel distance of EVs. According to a study published by Recurrent, at 100 degrees Fahrenheit, an EV will lose an average of 31% of its range.
That isn’t a matter of physics, though, or at least not directly. The EV will automatically try to cool its batteries while running, but that very process, of course, takes power — which all comes from the batteries. So energy that could have been used to take you farther is instead getting diverted to keeping itself from overheating.
What’s more, charging up an EV in high heat actually puts additional stresses on the batteries, accelerating their demise. If possible, wait to charge until the temp comes down a little bit.
