The companies said on Friday the new investment in their Ultium CAM plant, expected to start operating in 2025, will be used to set up additional facilities for local on-site processing of critical minerals used in electric vehicle (EV) batteries.

The companies had invested about $327 million in the plant last year, according to media reports.

The latest investment in capacity is expected to support GM's target to build 1 million EVs in North America by 2025 as major automakers push to make them more accessible to consumers and eventually establish cost parity with internal combustible engines.

Shares of GM rose 1.5% to $33.50 in premarket trading.

In April, GM also partnered with Samsung SDI and the companies said they will invest over $3 billion to build an EV battery manufacturing plant in the United States.

GM-POSCO's Ultium CAM, a joint venture established last year, will support production of about 360,000 Chevrolet, Cadillac, GMC, Buick and BrightDrop vehicles annually between 2025-2030 in North America.

The latest investment from GM and POSCO comes days after Canada's federal government and the Quebec province each provided about C$150 million ($112 million) for the facility in Becancour, Quebec that will produce cathode active material (CAM) for EV batteries.

CAM includes components such as processed nickel, lithium and other materials that make up about 40% of the cost of a battery. Cathodes are also the most complex and costly chemical component of an electric vehicle battery.

(Reporting by Priyamvada C in Bengaluru; Editing by Shinjini Ganguli)