Ganfeng, based in southeastern China's Jiangxi province, is one of the world's biggest producers of lithium, a key ingredient in rechargeable batteries, and a supplier of electric carmaker Tesla.
It bought a 37.5% stake in the Cauchari-Olaroz project from Chile's Sociedad Quimica y Minera, or SQM, in 2018 and said in April its Ganfeng Lithium Netherlands Co unit would subscribe for new shares in the operating joint venture (JV) Minera Exar to raise this to 50%.
"The board is pleased to announce that all the conditions precedent set out in the transaction agreement have been fulfilled and completion of the acquisition took place on 17 August 2019," Ganfeng said in a Hong Kong stock exchange filing.
Its JV partner in Cauchari-Olaroz is Toronto-listed Lithium Americas Corp, which says the project is on track to start production in 2020.
(Reporting by Tom Daly; Editing by Mark Potter)
