By NORIHIKO SHIROUZU

SHENZHEN, China — BYD Auto Co. is expected to unveil here Sunday what it claims as China’s first mass-produced electric vehicle, the BYD F3DM — one key reason why the investor Warren E. Buffett invested $230 million to take a 10% stake in BYD Auto’s parent company.

Shenzhen City Mayor Xu Zongheng said Saturday the 2008 China High-tech Fair, opening here Sunday, will showcase, among other “innovative achievements” by Chinese companies, the F3DM, an electric car the home-grown auto maker is planning to launch in China by the end of November, pending government approval.

The F3DM (DM stands for dual mode) is an electric vehicle with a small gasoline combustion engine on board to charge the car’s battery when it runs out or assist the electric engine when accelerating. The car, capable of going as far as 100 to 110 kilometers all on electricity when fully charged, is similar in design to the much-hyped Chevy Volt, which General Motors Corp. is scrambling to launch by the end of 2010.

With the F3DM, BYD is launching a so-called plug-in hybrid electric car two years ahead of GM and Toyota Motor Corp, the two global automotive giants that have pledged to come up with similar green cars by 2010. Both GM and Toyota say they are taking more time to make sure lithium-ion batteries they are using for their electric cars are safe.

BYD uses iron-phosphate-based lithium-ion batteries, which it claims it has developed on its own, for the F3DM. Wang Chuanfu, chairman of BYD Co. — the auto maker’s parent company, said those batteries are “inherently safe” because they are more chemically stable, although they compromise to some extent the ability to pack energy in each cell, compared with more conventional lithium-ion batteries.

Mr. Wang declined to provide a sales target or a price range for the new electric car, but he had said at an industry conference in Beijing earlier this year that the car could carry a price tag of about 150,000 Yuan to make the car comparatively more affordable.

This ability by BYD to offer a green car at an affordable price is one of the several factors that have spurred MidAmerican Energy Holdings Co., 87.4% of which Mr. Buffett’s Berkshire Hathaway owns, to invest in BYD. According to BYD’s Mr. Wang, the company may accelerate its plans for entering the U.S. and European markets by using MidAmerican Energy’s money. It wasn’t clear immediately when BYD plans to launch products in the U.S. and European markets, however.

The Shenzhen company, better known for being a top global producer of rechargeable batteries for cell phones and other devices, began producing cars in 2005. It has since become one of China’s fast-growing home-grown brands with the gasoline-powered F3 compact sedan.