April 17, 2012. The average price of lithium-ion battery packs for electric vehicles fell 14 percent in the past year as production capacity exceeded demand. Batteries cost $689 a kilowatt-hour in the first quarter of 2012, compared with $800 a year earlier. Prices for batteries have dropped 30 percent since 2009, making electric vehicles less expensive. Electric vehicles such as Mitsubishi Motors Corp.'s i-MiEV, Nissan Motor Co.'s Leaf and Tesla Motors Inc.'s Model S require between 16 kilowatt-hours and 85 kilowatt-hours of storage, which accounts for about 25 percent of their cost. The industry has capacity to produce about 10 gigawatt- hours of battery packs more than it needs now, enough for 400,000 all-electric vehicles, and that surplus may reach 17 gigawatt-hours by the end of 2013. Battery prices may drop to about $150 a kilowatt-hour by 2030. About 43,000 electric vehicles were sold in 2011.