US car giant General Motors is a step closer to bringing its new generation electric hybrid car into production by awarding development contracts for the most important component: the battery.
The Chevrolet Volt, launched at this year's Detroit Motor Show, combines battery power with a conventional engine in a system that uses no fuel for the first 40 miles of driving.
The car's battery pack will consist of hundreds of lithium ion modules, mounted in a two-metre long array on the centre line of the chassis.
Michigan-based Compact Power and German firm Continental Automotive Systems will develop the modules.
The battery is just one way the Volt can use power, however; GM is also developing fuel cell technology and the internal combustion engine could be a unit fuelled by conventional petrol, diesel, biodiesel, pure ethanol or a blend of ethanol and petrol.
The Volt is part of GM's overall strategy to 'take the car out of the energy and environment debate,' said Chris Borroni-Bird, director of advanced technology vehicle concepts. 'The long-term goal is power from a hydrogen fuel cell,' he said.
Both batteries and fuel cells have pros and cons, he added: fuel cells have a better range and are quick to refuel, and batteries are more durable and affordable. However, Borroni-Bird said, GM is confident it can make a fuel cell with a 300 miles range, durable over 150,000 miles of driving, for a cost of $25/kW of power, by 2010.
The switch to electric power will also allow the control systems of cars to be completely redesigned, with by-wire systems replacing brakes and mechanical steering.
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