Deliveries under the deal will begin in August, with 20,000 dry metric tonnes of concentrate to be shipped annually for six years.

Mining activity in May dropped 2.3% compared with the same month in 2018 as the sector continued to confront sharply falling ore grades at its largest deposits.

The projects mark one of the the biggest expansions of solar and storage ever proposed in the US.

The miner expects to invest 525 million euros in the Centenario deposit with the aim of producing 24,000 tonnes of lithium carbonate equivalent per year.

POSCO's decision is the latest in a string of setbacks for Chile, which has struggled to modernize its lithium policies, boost output and develop a domestic battery industry.

The EV market has boomed in recent years, but still makes up just a fraction of total car sales.

Capital projects were overshadowed when investors turned their attention to other markets. That's all changing.