Freeport McMoran, which owns 51% of the mine, plans to invest around $7.5 billion to expand.
Teck has acquired a 6.89% ownership in the junior explorer.
Three projects were already announced for Oman, Saudi Arabia, and the United Arab Emirates.
The partnership between Codelco and SQM is a major component of president Boric's plan to boost the state role in Chile's production of lithium.