Method for recycling lithium cobalt oxide from waste positive electrode of lithium cobalt oxide battery

Abstract

The invention discloses a method for recycling lithium cobalt oxide from a waste positive electrode of a lithium cobalt oxide battery. The method comprises the following steps of: (1) feeding the waste positive electrode of the lithium cobalt oxide battery into a 1-2mol/L hydrochloric acid lixivium in which citric acid is dissolved, and reacting for 4-6 hours at 60-80 DEG C; (2) filtering the lixivium in the step (1) so as to separate aluminum foil and solid grains; and (3) washing and drying the solid grains; and (4) adding a lithium source into the solid grains to adjust the mass ratio of Co/Li in the solid grains, uniformly mixing, calcining and cooling so as to obtain lithium cobalt oxide. The method adopts the mixed acid of citric acid and hydrochloric acid as the lixivium so as to effectively separate a positive electrode material and the aluminum foil, the process is simple, and no toxic or harmful gases are generated. The first discharge capacity of recovered lithium cobalt oxide can still be 140mAh/g, and the discharge capacity after 40 times of charge and discharge circulation is not less than 90%.

Description

technical field [0001] The invention relates to a method for recovering lithium cobaltate from waste positive plates of lithium cobaltate batteries, and belongs to the technical fields of comprehensive resource utilization and nonferrous hydrometallurgy. Background technique [0002] Lithium cobalt oxide is a common cathode active material for lithium-ion batteries. Because of its good electrochemical performance, processability, high tap density and stable product performance, lithium cobalt oxide batteries occupy a large market share. As a big country in the production and use of lithium cobalt oxide batteries in my country, the recycling of used batteries and production waste has always been a major event involving the long-term occurrence of the country. According to the classification method of my country's solid waste formulated by the State Environmental Protection Administration, lithium-ion batteries and their production wastes belong to the category of hazardous wa...

AI Technical Summary

Problems solved by technology

The fire method mainly uses the method of calcination to volatilize the binder, carbon powder, etc. in the waste, and then add lithium cobalt to sinter to prepare lithium cobaltate, but this method will generate a large amount of toxic and harmful gases, and post-processing is more troublesome; The recovery method is a relatively mature method. It dissolves the electrode material through strong acid, and then uses precipitation separation, ion exchange and solvent extraction to separate and recover the metal elements contained in the leachate. However, the process of this method The process is long, the operation is cumbersome, and the energy consumption is high; there are also studies using dilute acid to corrode the aluminum foil and the positive electrode material, stirring to separate, but this method takes a long time to separate and the separation is not complete