Beneath California's Salton Sea lies 3.4 million tons of lithium, potentially enough to build 375 million electric-vehicle batteries

Here's something you may not know: many EV batteries begin their life thousands of miles away in South American mines, but that may not be the case for much longer. According to a U.S. Department of Energy fact sheet, the ground under California's Salton Sea is hiding a huge amount of lithium. We’re talking enough to build more than 375 million EV batteries, more than all the cars on U.S. roads today.

Why this desert lake matters so much
The Salton Sea isn't exactly known for clean energy. Most people know it for the heat and the smell. But something is happening deep underground that most Californians probably know nothing about. Deep below the surface is hot, salty water known as geothermal brine. Power plants have been pumping it up for decades to make electricity. Scientists now know that this same water is rich in dissolved lithium, the metal that your phone, laptop, and EV battery depend on.

That DOE estimate isn’t a guess. It comes from years of research conducted at Lawrence Berkeley National Lab. The team that mapped the amount of lithium sitting underground here was led by scientist Patrick Dobson. The figure of 3.4 million tons is the high-end projection from the Lawrence Berkeley National Laboratory study, which is based on an assumption of future gains in extraction technology. Even the safer, already-proven figure is 2.6 million metric tons.


Since 2004, the Salton Sea geothermal field has been producing about 120 million metric tons of brine per year, which contains about 198 parts per million of lithium. This means that approximately 127,000 metric tons of lithium carbonate equivalent (LCE) are extracted each year. The known reservoir is believed to hold 4.1 million metric tons of LCE, but under more optimistic assumptions, this could be up to 18 million metric tons.

This resource could eventually help the U.S. meet or even exceed the world’s demand for lithium for decades to come, according to the Department of Energy fact sheet.

America's lithium problem
This is the part that should actually make you a little concerned. The U.S. has very little capacity to make lithium at home, the Department of Energy fact sheet notes. Almost all the country’s needs are imported and not from a diverse set of places either. The U.S. Geological Survey’s 2024 report on lithium says that more than 90 percent of U.S. lithium imports come from just two countries, Argentina and Chile. A tiny remaining share comes from China.

Demand isn’t slowing down either. If the world sticks to its clean energy goals, global demand for lithium could grow more than 40 times larger by 2040, according to a report from the International Energy Agency. No other battery metal comes near that growth rate. A domestic source this big could really take the pressure off.

How you actually pull lithium out of hot water
You can’t just take a bucket and scoop lithium out of a lake. Instead, engineers rely on a process called Direct Lithium Extraction, or DLE for short. Here's how the process works: the geothermal plants at the Salton Sea already draw hot brine from deep underground to make power. DLE just adds another step. Machines extract the lithium from the brine before it is returned to the ground.

This approach uses existing infrastructure. Today, Salton Sea geothermal plants generate about 400 megawatts of power. The Department of Energy fact sheet says the area eventually could support as much as 2,950 megawatts. Even at today’s smaller scale, the brine flowing through these plants already carries about 21,500 tons of lithium each year, none of which is being captured.

There is a real environmental upside too. The traditional way to mine lithium is either through hard-rock mining or in vast evaporation ponds that need massive amounts of land and water. According to the fact sheet from the Department of Energy, DLE consumes about 99 percent less water per ton of lithium and releases almost no carbon dioxide.

It's not a done deal yet
None of this lithium is actually being extracted and sold at scale today. These figures are resource estimates, not commitments, and they depend on new extraction facilities being built and proven at scale. The researchers at Berkeley Lab themselves concede that their long-term predictions are still early and will need more real-world data over time. Water use, air quality, and small earthquakes linked to geothermal activity are also being watched closely by regulators and local communities.

Why this could matter to you
Maybe you've been reluctant to buy an EV; maybe it's the price, or maybe it's the range anxiety. Either way, this is a story worth your attention. A reliable domestic lithium supply could eventually help reduce battery costs. It also could mean the U.S. is less concerned about fragile foreign supply chains, and it could create real clean-energy jobs in places like California's Imperial Valley. The lithium is already down there, waiting. What happens next comes down to how fast the technology and the funding can catch up to it.