“A Secure Energy Future: Progress Report” issued by the Obama Administration says the cost of batteries for electric and hybrid cars will drop within the next three years to an affordable level, helping the U.S. shake its dependence on foreign oil. Much of the expected price drop is attributable to increased battery production. A 10-kilowatt-hour battery that would give an electric car a 40-mile range would cost about $3,600 by 2015.