Summer Charging: 5 Warm Weather Tips for EVs

I'm Joe and I lead the EVgo Charging Crew. Please email me at support@EVgo.com or get in touch via Twitter and let me know what I can do to make it even easier and more convenient to fast charge your EV with EVgo.

Whew! It’s hot outside — or at least it usually is during the summer months. As temperatures rise, people who own EVs (or are EV-curious) may be wondering: how is owning an EV different than owning an internal combustion engine (ICE) vehicle when it comes to hot temperatures? This winter, we wrote about how cold weather affects charging and battery range. In warm weather, owning an EV is a little different than owning an ICE vehicle, but not by much.

Summer heat affects all cars, including ICE vehicles. When combustion engines get too hot, parts expand and warp, oil cooks and loses effectiveness, and engines can even seize up. Thankfully, engine cooling systems filled with antifreeze do a good job at keeping engines from getting too hot.

Similarly, EVs have cooling systems to keep their batteries from overheating. The thermal management system for the battery is built to both heat and cool the battery to keep it around 60-80 degrees Fahrenheit. This is quite a bit different from an engine cooling system which is primarily meant to only cool to a range around 190-210 degrees Fahrenheit (a combustion engine also produces a LOT more waste heat than a battery!).

An EV battery performs best within a certain temperature range because its power is generated by a chemical reaction that functions best within that range. When it’s hot outside, the thermal management system uses a small amount of power from the battery itself to maintain temperature (and when plugged in, the system pulls a bit of power from the grid to maintain the battery’s temperature).

All that said, here are a few warm weather tips to help you maximize your EV’s range and keep your battery healthy all summer long.

5 Warm Weather Tips for EVs:

1. Park your EV in the shade or in a garage (if you can).

If you don’t have access to a garage or shaded parking at home, whenever you’re out and about and have the option to park inside a parking structure or out in the hot sun, choose the parking structure! This will allow your battery and the cabin to cool down while parked. You’ll use less battery power cooling your car back down when you get back to your car, too.

2. Precondition your EV before getting inside. (If it’s plugged in, keep it plugged in while you precondition).

Preconditioning allows you to pre-heat or pre-cool the car’s cabin before you begin your journey, allowing you to use less of the energy stored in the battery for these functions. Most EVs come with an integrated app that you can use to precondition (by cooling or warming) your EV’s cabin before you get inside, but preconditioning may also be activated via the car’s media system. It’s best to precondition your EV while it’s still plugged in so that you use energy from the grid to cool the car and your battery down. This gives you more range, along with a comfier car when you get inside.

3. Ease up on the accelerator and brakes.

When it’s hot outside, easing up on the accelerator and brakes will use less energy, which will keep your battery cooler. You can also use ECO mode (or Chill Mode if you’re a Tesla driver), which limits the energy expended when driving.

4. Take it easy on the A/C if you need the range.

By itself, driving in hot weather will have a minimal impact on your range. Using your A/C on a hot day will have a small impact on your range. In fact, the heater in an EV typically uses more energy than the A/C, opposite that of a gas car. In city driving, you can consider rolling your windows down instead of using the A/C, but on the highway, rolling your windows down usually has a more negative effect (by producing drag) than just using the A/C moderately.

5. Limit your fast charge to an 80% State of Charge (SoC)* and charge at night whenever possible.

As your charging speed slows down throughout your fast charge, it’s usually a better use of your time to unplug after you reach 80% SoC. The energy transfer from the charger to your battery warms up your battery, so if it’s an especially hot day (and your battery is already warm), your EV may limit charging speeds to keep the battery cooler and healthier. At 80% SoC, you’re probably better off switching to an L2 charger if you need to top off. Charging at night when it’s cooler out will be even better for your battery, and you’ll be conserving energy on the grid if your utility company experiences demand constraints during the day.

If you have overnight charging available for your EV, it’s good to leave it plugged in with the SoC limit set to roughly 50%. For some vehicles, it’s also a good idea to have a small trickle charger, also known as a battery tender, on the 12V battery.* 

*Refer to your owner’s manual for more specifics on best practices for your EV model.

As EV adoption grows, many new EV owners might notice that charging and maintaining your EV is similar to charging and maintaining your smartphone. If you’re using your phone on a hot day and have a lot of apps running, it’s often a good idea to close a few apps to let your phone cool down. Your EV is similar. Thankfully, your EV’s BMS and thermal management system do an excellent job keeping your battery cool and healthy.

If you’re curious about what happens to public fast chargers in particularly hot weather, we have good news for you! EVgo chargers are built to withstand extreme weather and shouldn’t experience heat-related issues. If you ever encounter any issues on the EVgo network, don’t hesitate to give our EVgo Charging Crew a call at 877-494-3833. 

When the next heat wave comes, we hope these tips help you and your EV brave the higher temperatures. If you’re curious to learn more, check out our Charging Basics page, and click here to find an EVgo fast charger!