These EVs Have The Best Summer Driving Range 

Much of the Central, Midwest and Northeast U.S. is grappling with a dangerous heat wave this week, with temperatures soaring above 90 degrees Fahrenheit (32 degrees Celsius), even hitting 100F (37C) in some areas. Cold weather is well-known for affecting the range and performance of electric vehicles, but extreme heat like this can also have its own consequences.

But there are ways to mitigate the impact of extreme heat and some EVs are inherently better than others at resisting the effects of hot climate.

Battery health and data start-up Recurrent released a new study on Monday, analyzing real-world data from 29,719 EVs. It found that EVs indeed lose some range when the needle climbs to uncomfortable levels, but the range loss is minimal at 90F. When the mercury climbs to 100F, the range drop is more significant, although not as dramatic as when the polar vortex sets in.

For starters, EVs work perfectly fine even in extreme heat. The high-voltage batteries have a wide operating temperature. 

The battery will still function at those temperatures, but it may be less efficient in converting that stored energy into meaningful range and performance compared to when it is operating at more pleasant exterior temperatures. Tesla, for example, advises owners to avoid exposing its vehicles to ambient temperatures above 140F or -22F for more than 24 hours at a time.

Why Do EVs Lose Range In Extreme Heat?

EVs lose some driving range in extreme heat because the battery’s thermal management systems work extra hard to keep the cells cool, using its own energy to accomplish that.

When it’s burning outside, the electrolyte in a battery—which allows the ions to travel during the charge and discharge cycles—loosens up, causing energy to escape. The opposite happens when it’s freezing outside, with the electrolyte thickening and restricting ion movement.

Think of it like cake batter—the cake will only taste great if the consistency of the batter is perfect. Battery cells follow a similar principle, but have several redundant systems in place to ensure the consistency doesn’t go wrong.

Lastly, EVs also lose extra range in extreme heat because we tend to use air conditioning for longer periods of time, which drains more energy from the pack. But modern lithium-ion batteries are incredibly advanced, with sophisticated cooling systems that keep the cell temperature in check regardless of the weather outside.

Range Loss At 90F and 100F

Photo by: InsideEVs

According to Recurrent, the Audi Q8 E-Tron, BMW i4 and the Rivian R1S retain 98% of their driving range at 90F. The Hyundai Ioniq 5 and Rivian R1T retain 97% of their range, rounding out the top five models. The Ford Mustang Mach-E, Tesla Model 3 and Model Y aren’t all that far behind, retaining 96%, 95% and 94% of their driving range at 90F. On average the range loss is about 5%.

When you bump that up to 100F, the average range loss increases to about 15%. It can even be more than 20% on some EVs like the Cadillac Lyriq. So the Lyriq all-wheel drive with 319 miles of range may only deliver 250 miles of real world range if exposed to 100F or more for a prolonged period of time. 

At that temperature, the BMW i4 and Rivian R1S retained about 92% of their driving range. The Hyundai Ioniq 5 retains about 90% range at 100F.

Heat Pump Vs. No Heat Pump

Photo by: Ford

Recurrent also found that EVs with a heat pump—a device that recycles waste heat without consuming too much energy—lose more range in summer than EVs without a heat pump. Vehicles equipped with a heat pump lost 7% range on average in 90F and 15% in 100F. EVs without a heat pump lost 3% range on average in 90F and 13% in 100F.

That’s because heat pumps are optimized for cold-weather efficiency, not extreme heat. They’re great at keeping the cabin warm by repurposing waste heat from the drivetrain. But when the system is reversed to cool the cabin in hot weather, it can become less efficient than a simpler, conventional A/C setup.

Still, the difference in performance is relatively small and won’t be a dealbreaker for most EV buyers.

Best Practices To Preserve EV Range In Summer

Photo by: Tesla

Leaving your EV parked with a low state of charge isn’t ideal in any weather—hot or cold. In summer, the battery draws energy to cool itself, so it’s wise to keep the charge around 50%, or better yet, plugged in with an 80% charge limit. This helps maintain battery health by keeping those charge-carrying ions from drifting off.

If you’re leaving the car parked for an extended period—say, while you’re out of town—try to park it in the shade. That doesn’t mean your EV will melt if it’s left outside, but giving it a roof overhead is a smarter move when temperatures are soaring. If it’s outside, the cabin will likely heat up, and you’ll have to blast the AC to cool it down when you’re back, which is again, inefficient.

Plus, under a shade, the battery’s thermal management system will have less work to do to keep the cells healthy and cool.

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