General Motors is developing the Chevrolet Volt electric vehicle and its lithium-ion battery pack on parallel paths—and both have passed significant milestones en route to a targeted November 2010 launch.
Larry Burns, GM vice-president of research and development and strategic planning, tells Car and Driver in an interview that the design of the car has been frozen. Although the production model is not a twin of the Volt concept, the more conventional sedan bears a family resemblance to the Chevy Malibu. And in the interests of speed, it dips into parts bins of existing GM products wherever possible. That likely includes an existing four-cylinder gasoline engine as the onboard means of recharging the battery that, alone, gives the vehicle a range of only 40 miles.
The car was designed around the need to package a battery system with a 150,000-mile life, with enough performance for a 0-to-60-mph time of 8.5 seconds. The Volt concept also underwent changes to improve aerodynamics after extensive wind-tunnel testing.
Time to Hit the Road
And at an event in Detroit, GM execs discussed preparations for road-testing the lithium-ion batteries that will go into the production car—past tests were with nickel-metal hydride batteries. The next stage of testing begins this month, with battery packs in a 2001 Chevy Malibu mule to gather much-needed durability data as the team scrambles to simulate 10 years of usage over the next two.
Burns says initially GM canvassed numerous battery suppliers around the world as part of its e-flex program. After a “bake-off” between suppliers, GM is working with two deemed to “have the chemistries to get there.” Burns says there are eight criteria that GM determined its lithium-ion batteries must meet for automotive application, including such things as energy density, extreme temperature viability, the material set, and cost.
GM has shown a series of concepts with the E-Flex propulsion system: the original gasoline-electric Volt concept, a hydrogen-electric Volt, and the Opel Flextreme, which is diesel-electric.
The Volt will qualify as a PZEV (Partial Zero-Emission Vehicle), and there will be an E85 ULEV (Ultra Low-Emission Vehicle), but there are no plans for a diesel, execs said this week.
Second-Gen Work Under Way
Meanwhile, Burns says work is already under way on the second generation. He declines to give a timeframe.
Plug-ins may be exciting, but with a range of only 40 miles, they fall short in comparison to a family-size fuel-cell vehicle with a 300-mile range and zero emissions. Burns sees work on plug-ins as a complementary play to FCVs that convert hydrogen to electricity onboard, with batteries for power assist and to store energy regenerated in braking.
And he doesn’t anticipate that the Chevy Tahoe or other full-size vehicles—or even minivans, wagons or mid-size SUVs—will be offered as plug-ins. “It’s okay for a Cobalt-sized vehicle, but not something with twice the mass.” For larger vehicles, GM’s two-mode hybrid system makes more sense. And efficient gasoline engines will continue to play a significant role in the future, Burns says.
GM Determined to Be Fuel-Cell-Vehicle Leader
And although the Volt program has been designated a number-one priority at GM, fuel-cell-vehicle development is running full steam as well, Burns says, because GM is determined not to repeat with FCVs what happened with hybrids, with Toyota getting so far out in front of the market. “Toyota creamed us on the Prius,” Burns says. “It won’t happen again.”
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