The hot brine located in a vast underground reserve beneath the Salton Sea likely contains enough lithium to build batteries for 375 million electric vehicles, according to a new report released Tuesday.

The report from Lawrence Berkely National Laboratory and funded by the Energy Department represents the first time researchers have thoroughly quantified how much lithium might be present in the underground reserve.Researchers found that an estimated 18 million metric tons of lithium carbonate is likely available in the large underground pool, which isn’t connected to the Salton Sea.

That large of a lithium deposit could “enable the United States to meet or exceed global lithium demand for decades,” according to a press release from the Department of Energy.”

This is pretty significant, it makes this among the largest lithium brine deposits in the world,” said Michael McKibben, a geochemistry professor from UC Riverside who was among the 22 authors who worked on the report. “This could make the U.S. completely self-sufficient in lithium so we’re no longer importing it via China.”

In an emailed statement to The Desert Sun, Controlled Thermal Resources CEO Rod Colwell said the report “substantiates the robustness and scale of the Salton Sea resource” and “confirms much larger lithium reserves than originally thought.” Controlled Thermal Resources is one of three companies working on projects to extract lithium at commercial scale near the Salton Sea.

Currently, most of the lithium found in electric car batteries in the U.S. originates in South America, then is transported to China to make batteries.

Based on the portion of the geothermal reservoir that’s already been drilled out, researchers know there are at least 4 million tons of lithium in that portion of the brine. The 18 million figure comes from extrapolating what would be possible if the rest of the reservoir was drilled out to produce more geothermal power.

That would be enough for roughly 375 million electric car batteries, according to the Department of Energy – more than the total number of vehicles currently on U.S. roads.