The Chevrolet Volt is a battery-powered, four-passenger electric vehicle that uses a gas engine to create additional electricity to extend its range. The Volt draws from GM previous experience in starting the modern electric vehicle market when it launched the EV1 in 1996, according to GM Vice Chairman Robert A. Lutz.

"The EV1 was the benchmark in battery technology and was a tremendous achievement," Lutz said. "Even so, electric vehicles, in general, had limitations. They had limited range, limited room for passengers or luggage, couldnt climb a hill or run the air conditioning without depleting the battery, and had no device to get you home when the batterys charge ran low.

"The Chevrolet Volt is a new type of electric vehicle. It addresses the range problem and has room for passengers and their stuff. You can climb a hill or turn on the air conditioning and not worry about it."

The Volt can be fully charged by plugging it into a 110-volt outlet for approximately six hours a day. When the lithium-ion battery is fully charged, the Volt can deliver 40 city miles of pure electric vehicle range. When the battery is depleted, a 1L, three-cylinder turbocharged engine spins at a constant speed, or revolutions per minute (rpm), to create electricity and replenish the battery. According to Lutz, this increases the fuel economy and range.

"If you lived within 30 miles from work (60 miles round trip) and charged your vehicle every night when you came home or during the day at work, you would get 150 miles per gallon," Lutz said. "More than half of all Americans live within 20 miles of where they work (40 miles round trip). In that case, you might never burn a drop of gas during the life of the car."

In addition, the Chevrolet Volt is designed to run on E85, a fuel blend of 85 percent ethanol and 15 percent gasoline. Using E85, fuel economy of 150 mpg would translate into more than 525 miles per petroleum gallon.

General Motors has also announced it has awarded advanced battery development contracts to two suppliers to design and test lithium-ion batteries for use in the Saturn Vue Green Line plug-in hybrid SUV.

One contract has been awarded to Johnson Controls Saft Advanced Power Solutions, LLC, a joint venture between Tier 1 automotive supplier Johnson Controls and Saft. Another agreement was signed with Cobasys, in partnership with A123Systems. Cobasys, based in Orion, Mich., is a joint venture between Chevron Technology Ventures LLC, a subsidiary of Chevron Corp., and Energy Conversion Devices, Inc. A123Systems, based in Watertown, Mass., is a leading manufacturer of high power lithium-ion batteries.

The two test batteries, one from Cobasys A123Systems and the other from Johnson Controls Saft , will be evaluated in prototype Saturn Vue Green Line plug-in hybrids beginning later this year. While both are lithium-ion batteries, the chemistry differs significantly. The suppliers also use unique methods in the design and assembling of the battery packs.