A vital component of the batteries at the heart of electric vehicles and grid energy storage, lithium is key to a clean energy future. But producing the silvery-white metal 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. The researchers say their system can improve production at existing lithium facilities and unlock sources previously seen as too small or diluted to be worthwhile.
The core of the technique, described Sept. 7 in Nature Water, is a set of porous fibers twisted into strings, which the researchers engineered to have a water-loving core and a water-repelling surface. When the ends are dipped in a salt-water solution, the water travels up the strings through capillary action — the same process trees use to draw water from roots to leaves. The water quickly evaporates from each string’s surface, leaving behind salt ions such as sodium and lithium. As water continues to evaporate, the salts become increasingly concentrated and eventually form sodium chloride and lithium chloride crystals on the strings, allowing for easy harvesting.
Read more at: Princeton University
Meiqi Yang, a graduate student in civil and environmental engineering and one of the study's lead authors, operates the string-based approach for lithium extraction. (Photo Credit: Bumper DeJesus)