Warren B.

U.S. billionaire Warren Buffett intends to raise his stake in Chinese electric car and battery maker BYD Co. Ltd, BYD's chairman said on Monday, sending shares in his company up 8%.

MidAmerican Energy Holdings, a unit of Buffett's Berkshire Hathaway (BRK-B), bought 10% of BYD for $230 million last September, sparking a massive rally in the stock.

"MidAmerican has always intended to raise its stake in BYD because it believes BYD has good prospects in the development of renewable energy, but we are still considering (whether to sell more)," BYD Chairman Wang Chuanfu told reporters on Monday.

BYD, Hong Kong's largest listed auto stock, also said it expects to sell its e6 electric car in the United States in 2010, a year ahead of schedule.