Researchers have developed a cheaper and more sustainable method for lithium extraction
Spotted: Lithium is a vital component of electric vehicles (EVs) and electric grid storage batteries. Currently, the element is primarily extracted from underground liquid brine reservoirs. The brine is pumped to the surface and distributed to evaporation ponds, where it remains for a period of months or years until most of the liquid water content has evaporated, leaving behind the alkali metal lithium. This is not only time-consuming, but the process generates a considerable amount of toxic waste on the land used.
Now, researchers at Princeton University, led by Professor Zhiyong “Jason” Ren, have developed an extraction technique that gets around these limitations by reducing the amount of land and time needed for lithium production. The technique, described in the journal Nature Water, is based on porous fibres with a water-loving core and water-repelling surface.
The fibres are twisted into strings, and these are dipped in the evaporation ponds. The brine water travels up the strings through capillary action and quickly evaporates, leaving behind lithium salts. Further evaporation concentrates the salts further and eventually forms lithium chloride crystals, which are easily harvested.
The lithium crystals can be collected without the use of additional chemicals – further reducing the industrial waste produced. The researchers claim the entire process can cut the amount of land needed by more than 90 per cent and accelerate the evaporation process by more than 20 times over current methods.
The team behind the technique has been supported by the Princeton Catalysis Initiative and has an award from Princeton’s Intellectual Property Accelerator Fund, as well as seed funding from the Princeton Centre for Complex Materials. Study co-author Sunxiang (Sean) Zheng is leading the launch of a startup, PureLi, which hopes to eventually market the technology for commercial use.
The researchers are not the only ones focused on improving the sustainability of lithium batteries. Other approaches Springwise has recently spotted in the archive include using beads to absorb the brine and batteries made from sodium instead of lithium.
Written By: Lisa Magloff