A new technique for extracting lithium could bypass the slow, water hungry evaporation ponds that have long made battery production an environmental problem. Researchers at Columbia Engineering in the United States have developed a method that pulls the metal directly from salty underground brines using a solvent that changes behavior with temperature. The process works even on low quality lithium sources that current technologies cannot use efficiently.
A solvent that switches on and off with heat
The method is called switchable solvent selective extraction, or S3E. At room temperature, the solvent absorbs lithium and water from the brine. When heated, it releases purified lithium and water while regenerating itself for reuse. During testing, the system extracted lithium at rates up to 10 times higher than sodium and 12 times higher than potassium. It also removed magnesium, a common contaminant, through a chemical precipitation step. The system does not rely on specialized binding chemicals or extensive postprocessing, which sets it apart from many existing direct lithium extraction approaches.
Why current lithium production falls short
About 40 percent of the world's lithium supply comes from salty underground brines beneath desert regions. Most producers use solar evaporation, pumping brine into enormous outdoor ponds and leaving it exposed to the sun for months or even years until enough water evaporates. This method requires dry climates, flat terrain, and vast stretches of land, making it practical only in select places such as Chile's Atacama Desert and parts of Nevada. It also consumes significant water in already water stressed regions. The Columbia team published their findings in the journal Joule, noting that solar evaporation alone cannot match future demand.
The significance of this work lies in its potential to unlock lithium reserves that current methods cannot reach. By making extraction faster and less dependent on specific geography and climate, the technique could help diversify supply and reduce the environmental footprint of battery production. The researchers did not speculate on commercial timelines or costs, but the method offers a clear alternative to a process that has long been one of clean energy's dirtiest secrets.
