General Motors has announced a next-generation hybrid system using a new, more powerful, lithium-ion battery made by Hitachi.

The high-volume system will be introduced in North America in 2010 and then rolled out world-wide.

GM said this new cost-effective technology would improve fuel economy by up to 20% while the new battery would help make the new system nearly three times more powerful than the current one.

"This new system is another important step in our broad-based strategy to reduce vehicle fuel consumption and emissions," Wagoner said in Geneva on Tuesday.

The new system will build upon the belt-alternator-starter hybrid technology currently available in the North American market Saturn Vue and Aura and Chevrolet Malibu.

By building on this proven technology, Wagoner said, GM would be able to make the system more cost-effective and expand its application in GM's global vehicle lines.

"In order to have a real impact in reducing oil consumption, oil imports, and CO2 emissions, advanced technologies must be affordable enough to drive high-volume applications," he said.

"We plan to roll out this next-generation hybrid technology globally, across our brands and regions, starting in 2010 in North America, and we expect that volumes will eventually exceed 100,000 units annually."

The next-generation hybrid will complement GM's two-mode hybrid system launched in 2007 in the Chevrolet Tahoe and GMC Yukon large SUVs and to be offered this year in the Cadillac Escalade full-size SUV and the Chevrolet Silverado and GMC Sierra full-size pickups.

The first front-wheel-drive application for the two-mode system will be in the 2009 Saturn Vue Green Line SUV.

GM said the increased power from the lithium-ion battery will allow the next-generation system to be used in a wide range of global powertrains, including naturally aspirated engines, new high-efficiency turbocharged engines, bio-fuel engines and diesels.

The technology is being shown at Geneva in the Saab 9-X BioPower hybrid concept which can achieve 117g CO2/km emissions and projected fuel consumption of just 4.9l/100 km (48 mpg) when running on petrol on the EU combined test cycle.

This new hybrid system helps optimise fuel efficiency and reduce emissions by turning the engine off at idle; offering brief electric-only propulsion; using a more powerful electric motor to enhance engine efficiency; extending fuel cutoff during deceleration; extending regenerative braking to recapture more energy; and performing intelligent hybrid battery charging.

For additional energy savings, a six-speed automatic transmission also may be used, depending on the vehicle application, GM said.

GM's current hybrid system was introduced in 2006 in the Saturn Vue Green Line SUV and Shanghai GM announced in January that the Buick LaCrosse Eco-Hybrid sedan would be its first application in Asia-Pacific markets.

By the end of 2008, GM will offer eight hybrid models in North America and nine worldwide, and will introduce 16 new hybrid vehicles over the next four years.