Reuters: General Motors Corp will invest $30 million in its planned U.S. plant that will build next-generation batteries for its all-electric Chevrolet Volt, the head of GM’s flagship Chevrolet brand said on Tuesday. The facility, scheduled to open in Michigan in 2010, will assemble lithium-ion battery cells manufactured by South Korea’s LG Chem Ltd into 400-pound packs, which will power the heavily touted Volt plug-in car. “We chose Chevy because we can’t be niche with the Volt. We …