Posco Chemical, a chemical materials unit of South Korean steel giant Posco, signed a deal to supply General Motors with 13 trillion won’s ($10 billion) worth of cathode materials on Thursday.

Cathode materials determine the capacity and average voltage of batteries.

With the deal, Posco will now supply high-nickel cathode materials, largely used as electric car batteries, to LG-GM joint venture Ultium Cells for three years.

Posco chemical also plans to build production lines in North America to meet the demands for GM’s expanding electric car business.

GM and Posco Chemical plan to cooperate further to establish a global supply chain for electric vehicle batteries by establishing a precursor factory that will produce raw materials for cathodes, and signing additional supply deals for cathode and anode materials, according to Posco Chemical.