Chinese electric vehicle maker Nio has invested in a startup firm that is developing fusion technologies, according to a source with direct knowledge and a company filing, placing more bets in other areas of the energy sector.

The newly established company, Neo Fusion, will research and develop technologies that aim to bring controlled fusion for commercial uses globally in two decades, the source said.

With registration capital of 5 billion yuan ($723.37 million), Neo Fusion is 50% controlled by China's eastern province of Anhui government-owned energy companies and investment arms, according to the financial details in the company registration filing seen by Reuters.

Nio invested 995 million yuan for a 19.9% stake while Nio Capital, the investment firm founded by Nio's chief executive William Li, invested 505 million yuan for a 10.1% share, it showed.

"Staying true to the original aspiration of Blue Sky Coming, Nio aims to facilitate the R&D and commercialization of nuclear fusion technology by making financial investment into this project," which plans to attract more strategic and financial investors in phases, Nio said in a statement to Reuters on Friday.

Nio Capital and Anhui's State-owned Assets Supervision and Administration Commission did not immediately rely to requests for comment.

Fusion is seen to one day be able to help the world slash emissions linked to climate change. Unlike today's fission reactors, it can generate power without producing long-lasting radioactive waste.

Technological advances in recent years have brought it closer to being achieved in reality, sparking an investment spree among companies and governments globally, including the United States, Japan and China, which want to dominate the next generation of energy technology.

The investment by Nio also underscored the loss-making EV maker's ambitions in the power and energy sector.

While some people have criticised battery swapping stations as a costly investment, Nio argues that battery swapping is both a quicker solution to powering up EVs and an energy storage facility to improve grid stability.

It has also been developing battery technologies and is planning to build a battery plant with annual capacity of 40 gigawatt hours in Hefei city in Anhui province, Reuters reported previously.

($1 = 6.9121 Chinese yuan renminbi)