Lithium Recycling from Used Li-ion Batteries using Innovative Electrodialysis with Lithium Ionic conductor

In recent years, the industrial importance of lithium (Li) has increased due to its use in Li-ion batteries. Previously, the author had developed a method for the recovery of Li from seawater using a Li ionic superconductor functioning as a Li-ion separation membrane (LISM). In this method, only Li ions were successfully recovered from seawater through the LISM. Consequently, the author then developed a new innovative method for recycling Li from used Li-ion batteries using the LISM. This innovative method involves the use of an LISM, whereby only Li ions in a solution of used Li-ion batteries permeate from the positive electrode side to the negative electrode side during electrodialysis; the other ions, including Co, Al, and F, do not permeate the membrane. Li0.29La0.57TiO3 was selected as the LISM. The positive side of the dialysis cell was filled with used Li-ion battery solution. Then the negative side was filled with distilled water. The applied dialysis voltage was 5 V, and electrode area was 16 cm2. The Li recovery ratio increased with electrodialysis time. Subsequently, Co, Al, and F were not permeated. After electrodialysis, CO2 gas was bubbled in the Li recovery water to produce lithium carbonate (Li2CO3) as a raw material for Li-ion batteries. The Li2CO3 deposition was easily generated by the reaction of CO2 gas and the Li recovery solution as a lithium hydroxide (LiOH) solution. This new method for recycling Li-ion batteries shows good energy efficiency and is easily scalable. Thus, this electrodialysis method is suitable for the recovery of Li from used Li-ion batteries.