Title : Innovative Lithium Recycling Technique of Used Li-ion Batteries using Li Separation Method by Ionic Conductor: LiSMIC
In recent years, the industrial importance of Li has increased due to its use in Li ion batteries. I propose new method for recovering Li from used Li-ion batteries (LIBs) by using Li separation method by ionic conductor; LiSMIC.
Li0.29La0.57TiO3 (LLT) was selected as the Li separation membrane. Then, I demonstrate that the use of an acid-processed LLT enables us to efficiently extract Li from an Li-containing solution with high alkalinity owing to the Li adsorptivity on the surface of the LLT. The adsorptivity is generated by an ion exchange between Li+ and H+, and the closest known chemical composition of the adsorbent is found to be Ti0.98O1.892(OH)0.108. When the mixed alkaline solution of 0.1-M LiOH, NaOH, and KOH is used for the Li extraction test, the acid-processed LLT (LA–LLT) exhibits superior extraction rate than the unprocessed LLT. It extracts almost all Li from 200 ml of the solution in 72 h, and the maximum recovery speed reaches 3.5 mg/h, which corresponds to 13.5 mA of the electric current associated with the Li permeation through the LA–LLT membrane with a 16-cm2 area.
I also examined industrial application, such as a used LIBs solution, and the extraction was possible. Thus, LiSMIC is most suitable for the Li recycling of used LIBs.