Keeping an EV's batteries within their optimum operating temperature range is essential to getting the highest performance and longest life cycles possible from them. Too hot and charge seeps from the cells, too cold and the vehicle's range can drop up to 20 percent with charging sessions taking significantly longer than they would in warmer climes. This is why heat pumps, devices that scavenge waste heat from a vehicle's engine components to provide power other systems, have been finding their ways into a number of electric autos in recent years. Tesla has added them to its Model Y, 3, and S Plaid; Polestar includes them with the PS2 single-motor, and Rivian, well, Rivian does it a little different, but on Monday, GM announced its latest entry into waste heat reclamation game with the debut of its "Ultium Energy Recovery" system.
The UER is "based around an advanced automotive grade heat pump that captures and repurposes otherwise wasted energy," Tim Grewe, GM director of electrification strategy, said during a press call last week. "It's more sophisticated than even the most advanced thermal heat pump that you would find in modern homes."
"We could do several things with this energy," he continued, "including increase the range of our EVs, power low-level electrical functions like heating, and even pre-conditioning of our battery for faster charging and acceleration." For an EV like the new Hummer, the estimated ten percent increase in range that this system provides translates into an extra 30 miles of range. Similarly, this heat pump is what drives the Hummer's Watts to Freedom launch control function, autonomously conditioning the battery temperatures to the optimal level with which to dump as much current they can, as fast as they can, in order to propel the 9,000-pound EV SUV from 0 to 60 in 3 seconds flat.
"It's one of those situations where you want to get the magnets in the motor as cold as you can to give you ultimate torque going forward," GM energy recovery system project manager, Lawrence Zeer, said on the call. "And then you want to warm up the battery because the battery is give you a little more power when they're warmed up." Zeer also points out that given the immense size of these batteries — the Hummer's is rumored to weigh more than 2,900 pounds — "it's got a lot of heat capacity to it." Conversely, the pump will also automatically precondition the batteries if the driver selects an upcoming charging station from the nav computer and can cool the cabin as easily as it warms it.
GM plans to include the recovery system across its electric vehicle lineup including the Hummer EV, the Lyric, and the upcoming Blazer EV. And since the recovery system is already standard throughout GM's EV offerings, folks who've pre-ordered their Lyric and Hummers won't have to turn around and head back to the dealership for a service installation.