EV drivers have long known the effect that cold weather can have on batteries. However, cold isn't the only weather that needs to be considered when it comes to EV battery performance. Overheating is a problem that affects all cars which can happen a lot when it's extreme heat out there. And by extreme heat, we mean that when the temperature is above 95°F or 35°C. We will explain how heat can affect EV batteries, as well as some tips for EV owners to help you find the best way to take care of your cars during hot weather.
How extreme heat affect your EVs?
Most electric vehicles are powered by lithium-ion batteries which have an ideal operating range of around 70 degrees Fahrenheit. When it is hot outside, the temperature control system uses a small amount of energy from the battery itself to maintain the temperature. It will reduce the driving range. Still, overheating can happen. An overheated battery can cause issues with charging, as the charging speed can decrease or halt altogether for safety.
Tips for charging during hot weather
- Don't park in the sun
All electric vehicles soak up the heat when you park them in direct sunlight. And the lithium-ion batteries in your EV can lose charge if left out in the sun for too long. Neither of those situations is good for battery range, so be sure to park in the shade whenever possible.
- Preconditioning
We have learned about preconditioning in our article about charging in cold weather. It's also useful when in hot weather. Preconditioning the car for a few minutes while it's still plugged in.
- Charge the battery slowly at night
By charging at night, you can avoid the extreme heat and peak hours. Charging in the hot sun not only means you won’t get the best out of your battery, it’s also a drain on the power grid.
- 80% rule
Lithium batteries aren't as efficient as they could be and need to be replaced sooner when they're overcharged. Charging higher than 80% whilst the weather is hot can cause cell degradation, a condition that occurs when lithium battery cells lose the capacity to charge at their original rate.
