Samsung Electronics Co Ltd has paid 3 billion yuan ($449 million; 408 million euros) for a stake in Chinese electric-car maker BYD Co Ltd, which is backed by US billionaire investor Warren Buffett's Berkshire Hathaway Inc.

Shanghai Samsung Semiconductor, a unit of the South Korean company, has bought 52.26 million shares at 57.4 yuan a share in a private placement that raised 14.5 billion yuan in total, according to BYD on July 21.

The investment gives Samsung a 1.92 percent stake, making it the ninth-largest investor in the company.

BYD intends to use the proceeds of the private placement to fund an expansion in lithium-ion batteries production and research and development in new energy vehicles.

The smartphone and memory chipmaker said last week that an investment in BYD would strengthen Samsung's semiconductor business for cars. The two companies plan to cooperate in e-vehicle components and promote automotive-related businesses.

Last year, China surpassed the United States for the first time to become the world's biggest e-vehicle market. The Chinese government wants the sales of e-vehicles to exceed 3 million units by 2025.

Electronics makers like Samsung are competing for a slice of automotive sales as carmakers use more electronic sensors and displays in their push for more automated vehicles.

BYD has 24 production hubs in China, and the company is to build a battery factory in Qinghai province. A new factory in Shanxi province is also expected to manufacture up to 5,000 e-cars, 5,000 electric special-purpose vehicles and 2,000 trucks for industrial and mining works annually.

Du Xiaoying contributed to this story.