A new study suggests that excessive heat can greatly diminish electric vehicle range. The findings are similar to other studies that show how excessive cold also reduces range. Thankfully, it seems as though the range is mostly unaffected unless the temperature is in the triple digits.
Seattle-based Recurrent studies and tests thousands of vehicles each year in order to analyze the relationship between batteries and their range. Its latest data indicates that when things get really hot, EVs could lose almost a third of their stated range. While Recurrent didn’t name names, it says that some vehicles saw a drop in their range of 31 percent when temperatures climbed above 100 degrees Fahrenheit (38 degrees Celsius).
Recurrent is the same company that last year found that freezing temperatures have a nearly identical effect. Both the Ford Mustang Mach-E and the Volkswagen ID.4 saw dips in range of 30 percent when temps dropped below 30 degrees Fahrenheit (-1 degrees Celsius). At the same time, it’s worth noting that less extreme temperatures exhibit very little influence on battery range.
Read: New Thermal Cloak Keeps EVs Running At Peak Performance
Recurrent also pointed out that its data about triple-digit range depletion is very limited for now. “Note that the range loss at 100 degrees is based on extremely limited data, and we will update it when we have more confidence in the value,” it says in the study. CEO Scott Case explained to Automotive News that gathering such data is tough because most driving is done early in the day before triple digits are reached.
According to Greg Less from the University of Michigan Battery Lab, the decrease in range at those high temps comes down to chemistry. “Once you’re above [104 degrees Fahrenheit] you start to have a breakdown of the passive emission layer on the anode, and that breakdown will then cause consumption of the liquid electrolyte, which will shorten the lifetime of your battery,” he said.
It seems as though we’ll have to wait to see if Recurrent releases any data on which models specifically suffer the most in high temps. Until then the lesson is clear, avoid driving electric vehicles in extreme weather conditions whenever possible.
