DETROIT—General Motors will build a new factory in North America as part of an upcoming joint venture with a South Korean chemical manufacturer.

GM signed a “non-binding term sheet” Dec. 1 to create a joint venture with POSCO Chemical. The automaker expects to execute definitive agreements soon, likely by the first quarter of next year, says Doug Parks, GM’s executive vice president of global product development, purchasing and supply chain.

GM and POSCO will then announce a site in North America to build a new factory by 2024 to process key battery materials used in GM’s Ultium electric vehicle platform.

Ultium will underpin and propel all of GM’s future EVs, starting with the 2022 GMC Hummer EV pickup that is being built at Factory ZERO in Detroit and Hamtramck.

“We need to control our own destiny especially when it comes to battery production,” Parks says. “The majority of the Ultium platform will be sourced, processed and produced in North America by 2025.”

In June, GM announced plans to build two new battery cell manufacturing plants in the United States by mid-decade in its joint-venture Ultium LLC with LG Energy Solution. Those factories will make the batteries for the Ultium platform. GM has not disclosed the locations.

GM is presently building two other Ultium battery plants. One is in northeast Ohio near GM’s former Lordstown Assembly plant and another is in Tennessee near its Spring Hill assembly plant, where it will build the 2023 Cadillac Lyriq electric SUV.

The new factory that GM will build with POSCO will process cathode active material (CAM) and feed it to the four Ultium factories. CAM is a key battery material that makes up about 40 percent of the cost of a battery cell.

“When the plant goes online in 2024, it will create hundreds of jobs,” says Parks. “This will be a significant investment by both companies.”