BEIJING (Reuters) - Chinese automaker BYD Co Ltd (1211.HK), backed by Warren Buffett's Berkshire Hathaway Inc (BRKa.N), on Sunday predicted an up to 91-percent profit increase in the first nine months of the year, as government policies drive green car sales.

The Shenzhen-based company forecast an 83 percent to 91 percent rise in net profit for the first nine months, between 3.6 billion yuan ($539.8 million) to 3.7 billion yuan, according to a stock exchange filing.

For the first half of 2016, BYD reported 2.3 billion yuan in profit, a 384 percent increase year-on-year, on the low end of the company's predicted increase of 382 percent to 425 percent.

BYD, which focuses on making green energy cars and batteries for personal electronics, had reported successive quarters of triple-digit growth since third quarter 2015 after years of favorable government policies finally sparked a boom in sales of full electric cars and plug-in hybrids.

Berkshire Hathaway's stake in BYD fell to 8.25 percent from 9.1 percent previously after a share sale in July in which South Korea's Samsung Electronics Co Ltd and other investors bought a stake in the Chinese automaker.

BYD's board recommended an interim cash dividend of 0.367 yuan per share, according to the filing.

(Reporting by Jake Spring; Editing by Stephen Coates and Raissa Kasolowsky)