G.M. Tones Down the Volt

RICK WAGONER, chairman of General Motors, unwrapped the production version of the series hybrid Chevrolet Volt as part of the company's 100th anniversary celebration on Tuesday. The Volt, whose small gas engine does not drive the wheels but keeps the 16 kilowatt-hour lithium-ion battery pack charged, will look nothing like the concept car that G.M. carted around to auto shows for years.