Summary:

This invention provides a lithium recovery method based on polyvalent ion salts and ultrasonic stripping. The method specifically includes: leaching the negative electrode material by using lithium extraction reagent to obtain solid-liquid mixture, using ultrasonic stripping to accelerate the leaching rate. The lithium extraction solution is an organic solvent dissolved with aromatic compounds and polyvalent ion salts. The obtained solid-liquid mixture is separated to obtain a Li-rich solution, which can achieve efficient recovery of lithium from waste lithium-ion batteries. By adding polyvalent ion salt in the leaching process and combining with ultrasonic stripping, the polyvalent ion salts with large ionic radius is embedded in the graphite layer to destroy the layered structure, so that the active lithium is exposed and it is easier to react with aromatic compounds. The time is greatly shortened and the efficiency is improved using this method.

Link: http://epub.cnipa.gov.cn/patent/CN117802323A