LOS ANGELES -- General Motors could begin production of wheel hub electric motors by the end of this decade, says r&d chief Larry Burns. The technology would allow easy conversion of conventional powertrains to hybrids.
The technology, still in the early stages of development at GM, packages an electric drive motor in the center of a wheel. Wheel motors would enable GM to turn a front-wheel- or rear-wheel-drive vehicle into an all-wheel-drive hybrid powertrain without radically re-engineering the vehicle platform.
GM officials discussed the technology here last week as part of a nationwide "tech tour" showing off hybrid and fuel cell vehicles.
Wheel hub motors are a key element in GM's vision for fuel cell vehicles, as detailed in the Autonomy concept vehicle, which was introduced at the Detroit auto show in January 2002. The Autonomy design centered on a thin "skateboard" platform that housed the fuel cell, with electric motors mounted at each wheel. Differing body designs could be attached to the skateboard, offering the owner the flexibility of a sports car, minivan or sedan.
But several technical hurdles remain to be overcome, including the costs of the system and the weight added at the wheel, which affects ride quality. The wheel hub motor weighs about 65 pounds, GM officials said. But the motors also require a liquid cooling system and battery.
Adding wheel motors to a conventional powertrain would create a parallel hybrid, where either powertrain can operate independently. The Chrysler group is working on parallel hybrid technology it calls Through the Road, using an electric motor to power two wheels and an internal combustion engine to power the other wheel set.
Current hybrids, such as the Toyota Prius and Honda Civic, are series hybrids, with the electric motor sandwiched between the gasoline engine and transmission.