San Francisco Chronicle: The next phase in the rebirth of the electric car is turning into a battle between General Motors and Nissan Motor Co. GM executives, speaking Tuesday at a plug-in car conference in San Jose, said their Chevrolet Volt will cost $41,000 when it hits the market later this year. The price had been the subject of intense speculation for years. That price puts the Volt in competition with the electric Nissan Leaf, which will cost $32,780 when it appears in December. Buyers of both …