Repair and regeneration method for lithium cobaltate positive active material in waste lithium ion battery

Abstract

The invention discloses a repair and regeneration method for a lithium cobaltate positive active material in a waste lithium ion battery. The method comprises the following steps: discharging the waste lithium ion battery, dismantling to obtain a waste positive plate, roasting the waste positive plate, dissolving in water, and filtering to obtain waste lithium cobaltate powder; mixing the waste lithium cobaltate powder with potassium pyrosulfate according to a certain ratio, roasting, leaching a roasted product by the water, adding a potassium carbonate solution into a leaching solution, filtering, supplementing a certain amount of lithium carbonate into filter residues, performing ball-milling, compacting, and roasting in a resistance furnace to obtain the lithium cobaltate positive material with good electrochemical performance, wherein filter liquor is subjected to component adjustment by sulfuric acid and then crystallized to obtain potassium hydrogen sulfate.

Description

technical field [0001] The invention relates to a technology for repairing and regenerating lithium cobalt oxide cathode active materials in waste lithium ion batteries. Background technique [0002] Lithium-ion batteries are a new generation of secondary batteries developed rapidly in the 1990s, and are widely used in small portable electronic communication products and electric vehicles. According to statistics, in 2009, the output of lithium-ion batteries in my country reached 1.87 billion, and in 2010, the output of lithium-ion batteries in my country reached 2.68 billion. Since the service life of lithium-ion batteries is generally 2-3 years, the problems of environmental pollution and resource waste caused by discarded lithium-ion batteries have become increasingly prominent. The problem of how to properly dispose of discarded lithium-ion batteries cannot be ignored. The recycling and reuse of resources such as Co, Ni, Mn, Li, Al, and Cu in waste lithium-ion batteries...

AI Technical Summary

Problems solved by technology

[0005] In the repair and regeneration methods of lithium cobaltate positive electrode active materials in waste lithium ion batteries that have been reported so far, the regeneration process uses sulfuric acid plus hydrogen peroxide, sodium thiosulfate, hydrochloric acid, and nitric acid to dissolve waste LiCoO 2 , acid gas, Cl 2 or NO x Exhaust gas, which has caused serious secondary pollution to the atmospheric environment

In addition, there are many subsequent treatment procedures and long processes for the leaching solution, resulting in high recovery costs; in order to improve the metal recovery rate and shorten the leaching time, the leaching process adopts a higher acid concentration and leaching temperature, which has high requirements for the anti-corrosion of the leaching equipment.

A method for re-obtaining lithium cobaltate by directly calcining the positive active material stripped from the positive electrode sheet of the spent lithium ion battery at high temperature, the electrochemical performance of the prepared lithium cobaltate cannot meet the performance requirements of lithium ion batteries

Using waste LiCoO 2 The method of roasting after mixing the powder with alkali metal sodium and potassium salts has the disadvantages of a large amount of alkali metal sodium and potassium salts in the roasting process and a large amount of precipitant oxalate in the recovery process, resulting in high recovery costs; LiCoO 2 Ball milling technology after materials are mixed with natural organic acid and hydrogen peroxide has the disadvantages of easy corrosion of ball milling equipment and generation of waste water containing organic matter in the recycling process