Design News for Mechanical and Design Engineers

“Normally, we pre-determine the design of the vehicle powertrain,” noted Frank Weber, global vehicle line executive and chief engineer of e-Flex Systems for GM. “But in the case of the Volt, we’re taking a much riskier path, where we are doing parallel development of the powertrain, battery, and vehicle itself.”

The highly-publicized Volt has drawn the interest of automotive community because it represents GM’s re-entry into the electric vehicle market. GM’s earlier entrant, known as the EV1, became a symbol of the electric vehicle movement’s failures when it was discontinued eight years ago. The EV1 was even the subject of a documentary movie, “Who Killed the Electric Car?”

Within the automotive engineering community, however, the Volt is considered vastly different because it uses an on-board internal combustion engine to supply power when its batteries run out of charge. Plans are for the car to have a 40-mile, battery-only driving range. When the batteries’ charge runs out, it will use the internal combustion engine to re-charge them, and gain as much as 600 more miles.

GM engineers said that this week that the giant automaker still harbors production intent for the vehicle. “It’s the project within GM that has the highest priority,” Weber said. “This is no scientific project and it’s no show car.”

The company has 500 engineers assigned to the project, Weber said.

Battery experts have questioned whether GM’s suppliers will be able to deal with some of the technical issues facing the project. Many believe that the battery packs, which will weigh more than 400 pounds, will cost too much to make the Volt profitable.

“We have always said this will be an expensive battery pack,” Weber said. “But once lithium-ion batteries are produced in higher volume, we expect the cost of those battery packs to go down significantly.”

Weber said EV batteries have improved tremendously in the past ten years. “In terms of energy and power, we have the same battery pack as the EV1, but it’s only one-third the size,” Weber said. “There is a very high confidence level that we can get it to the 40-mile range.”

Weber acknowledged, however, that any problems with the development of the battery pack could cause the car’s schedule to be pushed back. In that case, he said, the 2010 target “would be a stretch.”