General Motors will guarantee the lithium-ion battery in the Chevrolet Volt for 100,000 miles of driving or eight years, whichever comes first, the automaker announced Wednesday. Popular hybrid car models currently on the market, including the Toyota Prius and the Ford Escape Hybrid, have similar warrantees on their battery packs. The Volt, however, uses a different battery chemistry. Also, since the car runs purely on electricity from the battery for up to 40 miles, the Volt's battery is subjected to greater work loads than one in a gas/electric hybrid. Production of the Volt is still on schedule to begin in November, a GM spokesman said Wednesday. GM plans to produce 10,000 Volts, which will be sold in seven U.S. states, through the end of 2011. Production will expand to 30,000 cars in 2012.