Fisker unveiled the Karma hybrid four-door sports sedan at the 2008 Detroit Auto Show. First production car will be delivered by the end of 2009. The company is considering metro Detroit as it decides where to build the luxury hybrid-sedan

The vehicle is billed to drive 620 miles using the battery pack and onboard gas-powered generator. The first 50 comes from a battery pack that can be charged in a household outlet.

Fisker is one of several automakers in a race to be the first to offer a plug-in hybrid powered by a lithium-ion battery pack. The technology is promising, but risky, as developers test chemical combinations and software to keep the batteries from overheating.

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