CALIPATRIA, Calif.—In the U.S. hunt for lithium, an essential component of the batteries that power electric vehicles and cellphones, one big untapped source might be bubbling under a giant lake in Southern California.
The U.S. currently imports almost all of its lithium, but research shows large reserves in underground geothermal brines—a scalding hot soup of minerals, metals and saltwater. The catch: Extracting lithium from such a source at commercial scale is untested.
At California’s Salton Sea, three companies, including one owned by Warren Buffett’s conglomerate Berkshire Hathaway Inc., are pushing ahead with plans to do just that. Those efforts are backed by money from governments eager to secure supplies of critical minerals that are key to several modern technologies. Prices of lithium recently rose at their fastest pace in years as supply-chain…
