Canadian company Volt Lithium is currently testing a new technology at Alberta that extracts lithium, a key metal for batteries, from low concentration salt water, with lithium extraction rate going as high as 90%, in the hope of transforming old oilfields to lithium mine bases.
Demand for li-ion batteries is increasing at an unprecedented pace under energy transformation and the net-zero emission trend, as well as the popularization of EVs in each country, while power grids around the world would also require li-ion battery energy storage systems to regulate and balance electricity. However, activation of a mine takes 13 years. According to the statistics of the IEA, existing and emerging mines and salt water plants will only fulfill 50% of the demand.
Since the traditional method is now proven to be an untimely solution, it all comes down to new lithium extraction technology. Goldman Sachs pointed out from its report in April that direct lithium extraction (DLE) offers a potential revolutionary approach that allows fast and affordable elevation of salt water production, which resembles what shale is to oil.
Traditional lithium extraction from ground water primarily utilizes a large brine pool that evaporates water for a year or longer until lithium is extracted by chemical reagents, before it is processed into lithium carbonate or lithium hydroxide, where 40-60% of lithium can usually be extracted from salt water, and the cost for each ton of lithium carbonate equivalent is US$3,300-4,900. In comparison, DLE only requires several hours, and demands 95% fewer land, as well as a lower level of cost, since highly selective absorbent molecules are only needed in the salt water.
Volt recently announced that the demonstration project has managed to extract 90% of lithium from a pool that dropped to a concentration of 34mg/L, and 97% of lithium from a pool with a concentration of 120mg/L. The demonstration project is situated at an old and depleted oilfield in Rainbow Lake of Alberta, where the team first drilled more than 1,300 wellbores to obtain salt water.
Volt estimates the piece of land to contain about 4.9 million tons of lithium carbonate at a cost of roughly US$3,000/ton, and about 20K tons can be excavated each year. Volt pointed out that multiple oilfields in North America can be excavated through the patented technology, while the relatively simple process of the team could further lower the cost. The company is also establishing the first permanent pilot factory.
Goldman Sachs estimates that salt water roughly occupies 2/3 of global lithium resources, but only accounts for about 40% of current production. Production volume should rise from 50% to 80% if the DLE technology climbs to a penetration rate of 20-40%, which would ramp up lithium production by as much as 140K tons in 2028, followed by an increase of roughly 8% in global supply of raw materials.
(A brine pool for excavation of lithium carbonate is depicted in the first photo; source: shutterstock)