The world's EV revolution runs on lithium, and right now most of it comes out of the ground the slow way — pumped into vast outdoor ponds and left in the sun for months, or years, until the water boils off. A team at Columbia Engineering says it has a better idea, and they have just published the proof.
In a paper in Joule, researchers from Columbia University describe a new lithium extraction method they call switchable solvent selective extraction, or S3E (pronounced "S three E"). The technique uses a temperature-sensitive solvent to pull lithium directly out of underground saltwater brines — even when concentrations are low or the brine is contaminated with other metals.
How S3E works
At room temperature, the S3E solvent absorbs lithium and water from the raw brine. Heat it up, and the solvent releases a purified lithium stream and resets itself, ready to be reused. The whole cycle takes minutes rather than months and does not depend on hot sun, flat land, or unlimited water.
"There's no way solar evaporation alone can match future demand," said Ngai Yin Yip, the Columbia engineering professor who led the work. "And there are promising lithium-rich brines, like those in California's Salton Sea, where this method simply can't be used at all."
Far more selective than current systems
The technique's standout feature is selectivity — how well it grabs lithium while leaving other minerals behind. In lab tests, S3E pulled lithium 10 times more efficiently than sodium and 12 times more efficiently than potassium. A separate chemical precipitation step strips out magnesium, the contaminant most likely to ruin a lithium extraction process.
Unlike most "direct lithium extraction" systems being commercialized today, S3E does not depend on exotic binding chemicals or heavy post-processing. The trick is the way lithium ions interact with water molecules inside the temperature-responsive solvent — physics doing the work that complicated chemistry usually has to.
The Salton Sea — a hidden lithium superpower
To stress-test the system, the researchers ran it on synthetic brines designed to mimic the chemistry of California's Salton Sea, a geothermal region in the Imperial Valley thought to hold enough lithium to power more than 375 million EV batteries.
After four extraction cycles using the same batch of solvent, the team recovered nearly 40 percent of the available lithium — promising numbers for a benchtop demo. With further engineering, the team believes the process can run continuously at industrial scale, with the solvent recycled essentially indefinitely.
If S3E performs in the field the way it performs in the lab, the implications are significant. Lithium production could finally move into wetter, more developed regions like the Salton Sea or oilfield brines in the U.S. Gulf Coast, dramatically shortening supply chains and cutting the water and land footprint of an industry currently dominated by South America's "Lithium Triangle."
Why this matters for clean energy
Roughly 40 percent of the world's lithium today comes from brine evaporation in places like Chile's Atacama Desert. Those operations require flat, sunny terrain, enormous quantities of land, and water that nearby communities often need for drinking and farming.
A faster, less thirsty process means batteries can scale to meet the demands of EVs and grid storage without scaling the environmental costs alongside them. For the energy transition, that is exactly the kind of unsexy chemistry win that quietly changes the trajectory of decarbonization.
Columbia Engineering says the team is now working with industrial partners to test S3E on real-world brines.
