Comprehensive recovering method of waste lithium iron phosphate battery

Abstract

The invention provides a comprehensive recovering method of waste lithium iron phosphate batteries, which has simple and reasonable process, low recovering cost and high added value. The method comprises the following steps: utilizing an organic solvent to dissolve an adhesive on battery cell fragments, and realizing the separation of lithium iron phosphate material and clean aluminum and copper foils through screening, wherein the aluminum and copper foils are recovered by smelting; utilizing a NaOH solution to remove residual aluminum foil scraps in the lithium iron phosphate material, and removing graphite and remaining adhesive by heat treatment; after dissolving the lithium iron phosphate with acid, utilizing sodium sulphide to remove copper ions, and utilizing the NaOH solution or ammonia solution to allow iron, lithium and phosphorus ions in the solution to generate sediments; adding iron source, lithium source or phosphorus source compounds to adjust the molar ratio of iron, lithium and phosphorus; and finally adding a carbon source, and obtaining a lithium iron phosphate cathode material through ball milling and calcination in inert atmosphere. After the treatment of the steps, the recovery rate of valuable metals in the batteries is more than 95%, and the comprehensive recovery rate of the lithium iron phosphate cathode material is more than 90%.

Description

technical field [0001] The invention belongs to the technical field of recycling waste batteries, in particular to a method for comprehensive recycling of waste lithium iron phosphate batteries. Background technique [0002] With the explosive development of 3C electronic products and various electric tools, people's demand for secondary batteries has increased dramatically. The lithium-ion battery has the characteristics of being environmentally friendly, high specific energy (140Wh / kg), high voltage platform, long cycle life, good rate performance, small self-discharge, and no memory effect, which is far superior to lead-acid and Ni-Cd , Ni-MH batteries have been widely used in military and civilian fields. Large-capacity, long-life power lithium-ion batteries represented by lithium iron phosphate cathode materials are used in power batteries such as electric bicycles, electric motorcycles, and electric vehicles due to their advantages such as good safety, good cycle perf...

AI Technical Summary

Problems solved by technology

The above-mentioned patent only involves the recycling of positive electrode waste in the production process of lithium iron phosphate batching, mixing, sieving, coating, etc., and simply removes the binder, grinds and sieves the waste slurry generated during production. However, the chemical composition of the positive electrode material in the waste lithium iron phosphate battery has changed, so this physical recycling method is not suitable for the waste lithium iron phosphate battery

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