POSCO Group is moving its lithium business beyond resource acquisition and production capacity toward securing global customers, linking Australian hard-rock resources, Argentine brine and Korean processing facilities with battery supply chains in North America, Europe and China.

POSCO Holdings said on Aug. 19 that it signed a Strategic Framework Agreement with Ningbo Ronbay New Energy at the POSCO Center in Seoul to cooperate across the secondary battery materials value chain, including battery-grade lithium supply and battery recycling.

The agreement is significant not simply because POSCO is partnering with a major Chinese cathode materials producer, but because it could connect lithium assets accumulated over years of investment with one of the world's largest battery materials markets.

Under the agreement, the companies will cooperate on the supply of lithium produced by POSCO Pilbara Lithium Solution in Korea from Australian hard-rock resources, brine-based lithium produced by POSCO Argentina, and recycled lithium recovered from used batteries by POSCO HY Clean Metal.

POSCO Pilbara Lithium Solution plans to complete Ronbay's qualification process for its battery-grade lithium hydroxide by the fourth quarter of this year, laying the groundwork for potential commercial-scale supply.

The latest move fits into a broader lithium strategy POSCO has been building across several continents.

In April, POSCO Holdings signed an agreement with Australia's Mineral Resources to invest about $765 million in interests linked to the Wodgina and Mt. Marion lithium mines in Western Australia. The investment gives POSCO access to 30% of lithium concentrate attributable to the joint-venture interests.

Wodgina has lithium reserves equivalent to approximately 6.2 million tons of lithium carbonate, while Mt. Marion has about 2.2 million tons, according to POSCO.

Securing resources, however, represents only the upstream portion of the strategy.

In Korea, POSCO Pilbara Lithium Solution processes Australian lithium ore into battery-grade lithium hydroxide at its production complex in the Yulchon Industrial Complex in South Jeolla Province.

In South America, POSCO is developing its brine-based lithium business around the Hombre Muerto salt lake in Argentina, creating a second resource and production route independent of hard-rock lithium.

POSCO Argentina turned profitable in the second quarter of this year, providing an early indication that the group's long-term investment in Argentine brine lithium is moving toward commercial returns.

POSCO has also begun connecting this production network with major battery customers.

In February, the group signed a long-term agreement to supply SK On with up to 25,000 tons of lithium from 2026 through 2028. The volume is sufficient for batteries for roughly 400,000 electric vehicles and is expected to support SK On's battery projects in Europe and North America.

The Ronbay partnership potentially adds China to that customer map.

Ningbo Ronbay New Energy is a major Chinese cathode materials producer known for high-nickel cathode materials. The company has been expanding beyond nickel-cobalt-manganese, or NCM, cathodes into lithium iron phosphate, lithium manganese iron phosphate and sodium-ion battery materials.

For POSCO, completing Ronbay's qualification process would provide more than another potential customer. It could demonstrate that lithium hydroxide produced at POSCO's Korean facilities meets the requirements of a major Chinese cathode producer and provide a pathway into the world's largest battery materials manufacturing market.

Recycling represents another piece of the partnership.

POSCO HY Clean Metal already supplies nickel, cobalt and manganese to Ronbay's operations in China and EMT, Ronbay's precursor subsidiary in Korea. The companies plan to expand their cooperation toward a closed-loop system in which critical minerals recovered from used batteries are returned to battery materials production.

Taken together, POSCO's emerging lithium model stretches from resource ownership to processing, customer supply and recycling: lithium mines and salt lakes provide raw materials, Korean and Argentine operations convert them into battery-grade products, global battery and cathode companies provide demand, and recycling operations recover materials for reuse.

The strategy has become increasingly important under POSCO Group Chairman Chang In-hwa.

At the group's CEO Investor Day in July, Chang identified steel, lithium and energy as POSCO's three "Triple-core" businesses, elevating lithium alongside the group's traditional steel operations as a central pillar of future growth.

POSCO aims to establish annual lithium production capacity of 173,000 tons by 2033 and become one of the world's five largest lithium producers. It is also targeting more than 1.8 trillion won in operating profit from its lithium business by 2035.

The next challenge is therefore not simply expanding production capacity, but securing enough long-term demand to support those investments.

Lithium prices remain highly exposed to swings in electric vehicle demand and global supply. For producers, competitive resources and reliable processing capacity alone may not be sufficient; long-term customers and diversified end markets can become equally important to profitability.

POSCO's moves this year suggest that its strategy is increasingly addressing both sides of that equation. It has strengthened upstream access through Australian mine investments, advanced brine production in Argentina, secured a multi-year supply agreement with SK On for European and North American projects, and is now seeking to connect its Korean lithium hydroxide production with Ronbay in China.

The Ronbay agreement, however, remains an initial step. The key milestone will be whether the qualification scheduled for the fourth quarter leads to commercial supply volumes and a longer-term contract.

If it does, the partnership could mark an important transition for POSCO's lithium strategy — from building a global resource and production network to proving that the network can generate sustained demand across the world's major battery markets.

Yeon Choul-woong More by this reporter