In winter's chill, cold batteries mean trouble for plug-in cars

Nobody worried about cold-weather performance of electric vehicle battery packs when it was warm outside, but now that Old Man Winter has descended, the problem is beginning to surface. When cars have a range of no more than 100 miles, the loss of 20 to 30 percent of that is a very big issue indeed.

Carmakers have long known to expect reduced performance from lithium-ion batteries in cold weather, but the early adopters now driving around in BMW Mini E and electric Smart cars (in Europe) are guinea pigs for what they do in the real world. There is teething pain here; some people are having issues.

Timothy Gill, a New Jersey computer consultant describes the 65 to 70 miles he gets from his Mini E as “pathetic.” His experiences include needing a tow truck when the car was a mile from home — and he thought he had plenty of juice left. But he still loves his Mini E, as do most of the people testing it in New York, New Jersey and California.

As Consumer Reports points out, Mitsubishi warns drivers of its i-MiEV electric not to use the heater because it will cut the range in half. And the heater is a likely factor in the BMW Mini E’s range-loss, too. The Mini E uses ducting to direct warmed air at the batteries, but it’s an experimental program (with just 450 cars in the U.S. and 150 in Germany) so BMW is not likely to engineer a costly thermal management system for it.

Physorg