Posco International, the trading and energy arm of Posco Group, announced Tuesday that it has signed a $40 million contract with Australian mining company Black Rock Mining to secure natural graphite, a key material for secondary batteries.

The signing event was held on the sidelines of the joint annual meeting between the Australia-Korea Business Council and the Korea-Australia Business Council in Perth, Australia, Tuesday. The event was attended by Korea’s Trade Minister Cheong In-kyo, Australia's Resources Minister Madeleine King, Posco Group Chairman Chang In-wha, Posco International CEO Lee Kye-in and Kim Jun-hyung, head of Posco Holdings’ secondary battery materials department.

With this agreement, Posco Group now holds a 19.9 percent stake in Black Rock Mining’s Mahenge Mine in Tanzania.

Posco International previously signed a contract with Black Rock Mining last year to build a plant at the Tanzanian mine, which will supply 30,000 tons of graphite annually over 25 years once the plant begins operation.

This year’s contract involves an additional plant to double the total supply, with production to start in 2026.

The company explained that the contract aims to establish stable supply chains for graphite and, in addition, includes global sales rights for the material, which it plans to leverage to expand its graphite business. The company also stated that it estimates the industrial-grade graphite produced from the mine will be sufficient for domestic use.

“Posco will continuously explore new business opportunities that enhance the global competitiveness of South Korea’s key industries, such as metals and secondary battery materials. To this end, the group will actively utilize its global network and diverse industrial portfolios to build such supply chains,” said Chang during the signing event.