Now, researchers at Columbia Engineering have developed a new lithium extraction technique that could speed up production, reduce pollution, and tap reserves that existing technologies struggle to access.

Their findings, published in the journal Joule, describe a process called switchable solvent selective extraction, or S3E (pronounced S three E). The method uses a temperature responsive solvent to pull lithium directly from salty underground brines, even when lithium concentrations are low or mixed with other minerals that are difficult to separate.

New Lithium Extraction Method Shows Strong Selectivity

According to the research team, S3E demonstrated impressive selectivity 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, one of the most common contaminants in lithium brines, through a chemical precipitation step that separates the unwanted material.

Unlike many current direct lithium extraction systems, S3E does not depend on specialized binding chemicals or large amounts of postprocessing. Instead, it relies on the unique way lithium ions interact with water molecules inside a solvent that changes behavior depending on temperature.

At room temperature, the solvent absorbs lithium and water from the brine. Once heated, the system releases purified lithium and water while regenerating the solvent so it can be reused repeatedly.

Why Current Lithium Production Is a Problem

About 40% of the world's lithium supply comes from salty underground brines located beneath desert regions. Most producers rely on solar evaporation, a process that pumps brine into enormous outdoor ponds and leaves it exposed to the sun for months or even years until enough water evaporates.

This approach is heavily dependent on 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 requires significant water use in already water stressed regions.

"There's no way solar evaporation alone can match future demand," said Ngai Yin Yip, La Von Duddleson Krumb Associate Professor of Earth and Environmental Engineering at Columbia University. "And there are promising lithium-rich brines, like those in California's Salton Sea, where this method simply can't be used at all."

Salton Sea Lithium Could Power Millions of EV Batteries

To test the system, researchers used synthetic brines designed to mimic conditions at California's Salton Sea, a geothermal region believed to contain enough lithium to supply more than 375 million EV batteries.

After four extraction cycles using the same solvent batch, the team recovered nearly 40% of the lithium. The results suggest the technology could eventually support continuous large scale operation.

"This is a new way to do direct lithium extraction," said Yip. "It's fast, selective, and easy to scale. And it can be powered by low-grade heat from waste sources or solar collectors."

The researchers emphasized that the project is still at the proof of concept stage and has not yet been fully optimized for efficiency or maximum lithium recovery. Even so, they believe S3E could become a viable alternative to evaporation ponds and hard rock mining, which currently dominate global lithium production despite their environmental drawbacks.

Cleaner Lithium Production for the Clean Energy Transition

As demand for batteries continues to rise worldwide, cleaner lithium extraction technologies may become increasingly important for the clean energy transition.

"We talk about green energy all the time," said Yip. "But we rarely talk about how dirty some of the supply chains are. If we want a truly sustainable transition, we need cleaner ways to get the materials it depends on. This is one step in that direction."