Method for recycling lithium iron phosphate wastes in manufacturing link of lithium iron phosphate batteries

Abstract

The invention discloses a method for recycling lithium iron phosphate wastes in the manufacturing link of lithium iron phosphate batteries and relates to lithium ion batteries. The recycling method is characterized by comprising the following steps: after a pole piece to be recycled is put into a muffle furnace, baking is performed for 2-3h at the temperature of 400-600 DEG C, the decomposition of a binder fails, and an active material lithium iron phosphate and conductive agent powder completely fall off from a current collector aluminum foil; after the powder is put in the muffle furnace, baking is performed for 4-6h at the temperature of 650-800 DEG C, sieving is performed to obtain lithium iron phosphate power; filtering is performed, the lithium iron phosphate power is washed with deionized water, and an ethanol wetting agent after washing is added to obtain turbid liquid; soluble lithium salt, molysite and phosphate are proportionally mixed into an ethanol solution, the mixed solution is added into the turbid liquid for mixing, and vacuum drying is performed at the temperature of 120-140 DEG C; roasting is performed for 3-6h at the temperature of 650-850 DEG C in an inert gas atmosphere to obtain acceptable materials. The method has the advantages of being good in electrochemical performance of recycled materials, high in reuse rate and low in cost.

Description

technical field [0001] The invention relates to the manufacture of lithium ion batteries, and more specifically to a method for recycling and reusing lithium iron phosphate waste in the manufacturing process of lithium iron phosphate batteries. Background technique [0002] Lithium-ion batteries are widely used in portable devices, mobile power supplies, large electric vehicles, communication power supplies, and other fields due to their high operating voltage, high energy density, wide temperature range, long life, no memory effect, and environmental protection. application prospects. The structure of a lithium-ion battery is mainly composed of positive and negative electrodes, a separator, an electrolyte, and a casing. According to the manufacturing process of the existing lithium iron phosphate battery, the active material lithium iron phosphate, a conductive agent and a binder are generally mixed in a solvent to make a slurry, which is evenly coated on the current colle...

AI Technical Summary

Problems solved by technology

According to the manufacturing process of the existing lithium iron phosphate battery, the active material lithium iron phosphate, a conductive agent and a binder are generally mixed in a solvent to make a slurry, which is evenly coated on the aluminum foil of the current collector by using a coating equipment, while in During the coating and subsequent slitting process, it is inevitable to produce waste pole pieces and scraps that do not meet the process requirements, resulting in production loss and increasing production costs

[0003] At present, the recovery method of the lithium iron phosphate material of the positive electrode of the lithium ion battery is generally to remove the binder and the conductive agent through high-temperature baking, and then obtain it through sieving, but the electrochemical performance of the lithium iron phosphate obtained by this method is poor, and the reuse rate is low. not tall

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