Lithium is key to a clean energy future because it is a key component at the heart of electric vehicles and grid energy storage. But producing it comes with significant environmental costs. Among them is the vast amount of land and time needed to extract lithium from briny water, with large operations running into the dozens of square miles and often requiring over a year to begin production.

Now, researchers at Princeton have developed an extraction technique that slashes the amount of land and time needed for lithium production. This research, described in Nature Water, involves a set of porous fibers twisted into strings. When the ends are dipped in a salt-water solution, the water travels up the strings through capillary action and eventually evaporates, leaving behind salt ions such as sodium and lithium, which can be harvested. 

“We aimed to leverage the fundamental processes of evaporation and capillary action to concentrate, separate and harvest lithium,” said Z. Jason Ren, professor of civil and environmental engineering and the Andlinger Center for Energy and the Environment at Princeton and the leader of the research team. “We do not need to apply additional chemicals, as is the case with many other extraction technologies, and the process saves a lot of water compared to traditional evaporation approaches.”

“Our approach is cheap, easy to operate, and requires very little energy. It’s an environmentally friendly solution to a critical energy challenge,” Ren added.