By Ernest Scheyder

LOS ANGELES Exxon Mobil has yet to decide which lithium filtration technology it will deploy as part of its aggressive plans to become one of the world's top producers of the metal used to make electric vehicle (EV) batteries, an executive said on Tuesday.

On Monday, the oil giant unveiled its long-awaited lithium strategy and said it aims to filter the ultralight metal from reservoirs about 10,000 feet beneath the U.S. state of Arkansas. Reuters first reported the news last weekend.

Exxon's expansion into the sector will rely on one or more of a so-far unproven fleet of direct lithium extraction (DLE) technologies that Eramet, Sunresin, Rio Tinto and others are working to commercialize.

Choosing which DLE technology to license will be a crucial decision upon which Exxon's production of the battery metal will rely. The company has held talks with a range of DLE technology providers, including International Battery Metals and privately held EnergySource Minerals.

"We haven't chosen a (DLE) company yet. We're in the process of evaluating a number of companies," Patrick Howarth, Exxon's global product manager for lithium, said in an interview on the sidelines of the Benchmark Week 2023 strategic minerals conference in Los Angeles.

The company will provide details on its DLE process once it formally decides to proceed with its lithium project, a technical step known as formal investment decision, he said. He declined to be more specific on timing.

Even though it has yet to pick a DLE technology, Exxon is confident it can start producing lithium by 2027 on 120,000 acres in Arkansas that it acquired earlier this year, Howarth said.

"What we've seen as we've looked at a number of the (DLE) technology providers is pretty consistent abilities on the brine that we've got within Arkansas to extract lithium," he said.

Because it not yet chosen a DLE technology, Exxon also has not yet forecast how much lithium it ultimately aims to produce. The company is drilling test wells across Arkansas to study the underground brine reservoir.

"From there, we'll be able to come back with a more fulsome number about production ambitions," Howarth said.

Separately, Exxon has a lithium partnership with Tetra Technologies to develop a smaller parcel in Arkansas that is expected to be producing 10,000 metric tons of lithium per year by 2026.

Exxon is also studying where else in the world it could produce lithium, Howarth said.

(Reporting by Ernest Scheyder; Editing by David Gregorio)