Chevy, supplier tweak Volt battery pack for more range

DETROIT -- To boost the 2016 Chevrolet Volt's electric-only driving range to 50 miles from 38 on the outgoing first-generation car, engineers reduced the number of cells in the battery pack by about a third, to 192 from 288.

That might seem unusual, but General Motors engineers, working with Volt battery supplier LG Chem Power Inc., made the battery pack's individual cells slightly larger.

And using data gained from examining the batteries in about 300 first-generation customer-owned Volts, engineers increased the amount of power the 2016 Volt's electric motor drains from the battery pack by 9 percent before the gasoline engine kicks in.

The result: Two of the new cells have the same power as three of the old cells, and the 2016 Volt's battery pack weighs 31 pounds less than the 2015 car's pack. 

Weight reductions in the battery pack's T-shaped backbone, powertrain and elsewhere on the car also contributed to the increased electric driving range. But most of the increase traces back to the revamped battery pack, says Bill Wallace, GM's director of global battery systems engineering. 

Volt customers told GM they wanted to go farther on a single charge. GM tested the new Volt's batteries in the Chevrolet Spark EV, he said. 

"The experience from the Spark EV gives us exceptionally high confidence," said Wallace. Pricing for the 2016 Volt is expected to be announced late next month. GM has started building the first preproduction cars in suburban Detroit.