GM says Volt is on target for 2010 launch

“It is the No. 1 priority that we have,” says Frank Weber, executive in charge of the car.

The most recent milestone is installation of lithium-ion battery packs in test-mule Volts–they look like older-model Chevy Malibus outfitted with GM’s E-Flex technology–undergoing proving-ground road tests now. E-Flex should allow the Volt to travel 40 miles on electricity alone before the batteries must be recharged by an onboard generator powered by a gasoline engine (potential diesel or fuel-cell versions would come later). The Volt is expected to have a range of 400 miles. Earlier mules, using older nickel-metal-hydride cells and with battery-only range of only one mile, have been in testing since last fall.

This new testing stage will take about six months, GM says, before the company can move on to the next phase of development. The design is largely complete, but a driveable Volt prototype likely won’t be ready until mid-2009.

The design has changed significantly since the concept was unveiled amid great fanfare at the 2007 Detroit show. The front end has been rounded slightly to improve crash-impact safety and to accommodate an enlarged engine compartment. The roof has been raised slightly for passengers, and the company claims it can accommodate six-foot-two adults comfortably. It is based on GM’s global compact-car chassis, called Delta, which also will spawn conventional cars.

The exterior appearance is nearly finalized. One challenge has been making the car sleeker, and engineers are working at all hours in GM’s cavelike wind tunnel to improve the drag–critical to achieve the 40-mile electric range.

Aerodynamic drag accounts for about 20 percent of the energy consumed by an average vehicle. The original concept performed poorly in the wind tunnel, but GM says it has since reduced drag 30 percent.

Even with the changes, the car is expected to bear a resemblance to the concept Volt, which attracted attention for its eye-catching looks, says Bob Boniface, the car’s design director. In February 2006, he got the initial orders from GM car chief Bob Lutz to start sketching out ideas.

“All of those pieces that were important to the show car are still there. . . . If you see a car on the road, you’ll know it’s the Volt,” Boniface says.

The interior design, also nearly finished, is similar to the inside of the new Malibu, and the dual-cockpit setting appears to take styling cues from early-1960s Corvettes. It will seat four, and designers say it could have ambient lighting, a feature on some of GM’s upper-market vehicles. In keeping with the Volt’s green mantra, the headliner and carpet are expected to be made from recyclable materials, and seat foam will come from a soy-based derivative.

The T-shaped lithium-ion battery pack will be positioned in the center tunnel of the car, under the rear seats. The pack is about six feet long and weighs more than 375 pounds. Offsetting the battery’s weight is a smaller-than-average fuel tank. One concern engineers must address is that commuters might be able to run the Volt on electricity alone for months on end, while gasoline sits unused in the tank. Gas doesn’t age well in such circumstances, yet the engine must be able to run promptly and well on demand after such long fallow periods.

The batteries, though, are the key. Keeping large packs of lithium-ion cells cool and stable is a big challenge. GM intends to make the pack last 10 years or 150,000 miles and must cram its testing of the expected life cycle into the next two years. It’s cycling the batteries, discharging and recharging them on test machinery 24/7, aiming to complete 162,000 miles of testing (200 miles a day) before production. It’s also cranking up the heat in test labs to hasten the aging process to the equivalent of 10 years. The field of potential suppliers has been narrowed to two finalists, and both versions are undergoing side-by-side testing.

At a recent press preview of the Volt’s progress, GM execs were brimming with confidence that the car is on track for 2010, while acknowledging that hurdles remain. A reminder of this is displayed yards away from a Malibu test mule outfitted with E-Flex: a shiny red EV1.

As Roland Matthe, E-Flex engineering group manager, put it, “It’s not a done deal. This project is not normal in regard to risk in the automotive industry.”