Evonik wants to make lithium recycling from electric vehicle drive batteries easier, more economical and more environmentally friendly. A ceramic membrane process developed for this purpose should be ready for market in three to five years.
Evonik researchers rely on a ceramic membrane electrochemical process to efficiently process lithium. The process is already being tested in the lab on a pilot scale, according to the company.
At the end of the process, high purity lithium hydroxide should be obtained, suitable for the production of new batteries. And, according to Evonik, the process of achieving this goal should be characterized by a high degree of efficiency. The starting point is a black mass consisting of a mixture of cathode active materials. The lithium-containing leaching solution is obtained by hydrometallurgical processing, which, for example, recovers cobalt and nickel.
This is where Evonik's lithium-ion-selective membrane comes to the rescue: from the recirculating liquid side and the positively charged anode, it allows only positively charged lithium cations to reach the other side with the negatively charged cathode. There, lithium ions combine with hydroxide to form high purity lithium hydroxide. According to Evonik, the degree of purity is almost 100 percent.
This electrochemical process is intended to replace the hydrometallurgical processing of lithium, which has been the norm so far. The goal is to save water, energy and chemicals. In Hanau and Marl, Evonik is currently working on moving the process from the lab to a larger process. The experts are confident that they will bring the ceramic membrane manufacturing process to market maturity in three to five years. This year, the project prototype should be tested with external partners, pilot modules should be created in 2023, and the first larger modules in 2024.