Fortune profiles Warren Buffett and his investment in Chinese electric car and battery maker BYD.

Last fall Berkshire Hathaway bought 10% of BYD for $230 million. The deal, which is awaiting final approval from the Chinese government, didn’t get much notice at the time. It was announced in late September, as the global financial markets teetered on the abyss. But Buffett and Munger and Sokol think it is a very big deal indeed. They think BYD has a shot at becoming the world’s largest automaker, primarily by selling electric cars, as well as a leader in the fast-growing solar power industry.