Science

GM's Volt sparks debate

The buzz around GM's Volt electric car concept has hardly diminished since the company unveiled it three months ago.

The debate surrounding General Motors' Chevrolet Volt has been highly charged, to say the least.

The buzz around the electric car concept has hardly diminished since GM unveiled it three months ago at the North American International Auto Show in Detroit. It's been passionate, and not all of it good.

Critics have accused GM of capitalizing on the global-warming panic to give the financially troubled auto giant a much-needed PR boost.

GM has promised mass-produced electric cars were just around the corner since the first oil crises in the 1970s, some suggest.

They point to its aborted $1.5 billion US effort to market the EV1 in the 1990s as the latest evidence GM can't make good on its promises. Only about 100 of the battery-powered, two-seat commuter cars were delivered into drivers' hands in Arizona and California test markets, despite heavily subsidized leases.

The failure spawned a 2006 documentary — Who Killed the Electric Car? — that suggested a conspiracy between the automotive and oil industries to head off the move to electrics.

The theory is discounted by experts who point to the EV1's well-known problems, including limited range, especially if the heat or air conditioning was turned on, and its impracticality in power-sapping, cold-weather regions.

The car's lead-acid batteries themselves had evolved little since the days of the Ford Model T.

Volt charging ahead, GM says

But GM insists the Volt is for real.

The non-running mockup made a splash at the Detroit show and 300,000 people clicked onto a GM website to say they wanted the car to be built. The EV1 had its fans, too, but only a few opened their wallets.

Vice-chairman Bob Lutz, the company's product-development guru, told reporters at the Geneva Auto Show last month GM would have a running Volt prototype by the end of this year and had set 2010 as its internal target for production.

Lutz and other GM officials were quick to say a lot depends on beating the technological challenges, notably with the car's battery pack, but cynics saw it as another case of backpedalling.

"If we had ham, we could cook up some ham and eggs, if we had eggs," one wag observed on an auto technology website. "But we have a vision of ham and eggs."

Lutz, a legendary car guy who's worked for GM, Ford and Chrysler, replied on his own blog the Volt is not the automotive equivalent of vapourware (a promised computer product that doesn't materialize).

"I've said before that this is not a publicity stunt, but it's as if people don't want to believe it if we give them anything short of a guarantee of Volt delivery … with an exact date, time and sticker price," he said.

Lutz's targets are not far off, said Tony Posawatz, GM line director for the Volt project and the E-flex system that aims to mate electric drive with a variety of energy sources from ethanol to fuel cells.

The pressure has been on since the Detroit show, he said, and Lutz is simply signalling his encouragement.

"But we're obviously not making any production announcements yet — much work to do," said Posawatz.

The Volt concept differs from the defunct EV1 in several crucial areas.

It's a compact four-door sedan about the size of Chevy's Cobalt, intended to carry four or five people and a modest amount of luggage, which should make it attractive to more buyers.

It also has the muscular, hunkered-down look that's popular today, compared with the spacey, wind-cheating shape of the EV1.

Fill 'er up at the socket

But the most important difference is underneath. While the EV1 depended on batteries entirely, the Volt would have a small internal-combustion engine — a so-called range extender.

Studies showed most Americans drive their cars an average of 64 kilometres a day, which the Volt could manage on batteries alone. It could then be plugged in to recharge overnight.

On longer trips, its auxiliary engine kicks in, not to drive the car the way today's hybrids do but to recharge the batteries. That boosts its range to more than 1,000 kilometres and takes the Volt out of the commuter-car ghetto.

The core problem, though, hasn't changed since the EV1.

"The battery is the No. 1 issue," said Posawatz. "We are focused on it literally daily."

Hybrid vehicle battery packs are about a quarter the size of those envisioned for the Volt, which will make tougher performance demands.

In hybrids, the electric drive powers the car at very low speeds or acts as an acceleration booster. But in the Volt, it willdo it all.

The battery pack will have to cope with thousands of charge and discharge cycles over its lifespan, deal with expected heat buildup and be safe in a crash, among other things, said Posawatz.

"Our expectations are that the battery is a 10-year battery,"robust enough to last forabout 240,000 kilometres,he said.

Canadian conditions present the added challenge of cold-weather startup, driveability and range, which has GM looking at various approaches to keeping a parked car's battery pack warm even if it is not plugged in for recharging.

The batteries themselves will be lithium-ion, unlike the EV1's lead-acid units and current hybrids' nickel-metal hydride.

Hybrid battery contracts awarded

GM recently awarded contracts to two supply partnerships to develop batteries to use in its Saturn Vue plug-in hybrid SUV within the next year. Both are seen as in the running to supply battery packs if GM green-lights the Volt.

A123Systems of Watertown, Mass., near Boston, is one of the players and will scale up batteries it now supplies for cordless power tools.

"So there [are]really two steps," CEO David Vieau said. "One is to take the technology that we currently have and employ it in packaging size as a cell that's suitable for automotive, and the second step is to put those cells together in a large system."

Its partner, Cobasys of Orion, Mich., will develop the battery pack's overall system.

The other group working on the Vue project is a partnership of automotive supplier Johnson Controls and Saft Advanced Power Solutions.

Vieau believes Lutz's prediction of a Volt running prototype this year is achievable but mass production depends on how well GM can integrate all the technology at a price that appeals to Chevrolet's bread-and-butter market.

"The batteries are proven in a lab scale, but the work that they (GM) need to do to prove it out to their own satisfaction and a volume scale I guess is not within our judgment to make," said Vieau.

Public interest in the Volt gives its backers within GM additional leverage, said Posawatz.

"On the other hand, there are people that doubt we will have … the financial resources or associated courage to do it or not," he said.

"I think the proof points in that world will only be if we, in fact, do it."