Method for comprehensively separating and recycling materials in retired batteries

Abstract

The invention belongs to the field of waste battery recycling, and particularly discloses a method for comprehensively separating and recycling materials in a decommissioned battery, which comprises the following steps of: (1) disassembling the decommissioned battery to obtain a mixture of a positive pole piece and a negative pole piece; (2) soaking the mixture of the positive pole piece and the negative pole piece in water and stirring, so that the positive component material and the negative component material are stripped from the current collector; and (3) secondary sieving is carried out, so that a powdery negative electrode component material, a sheet-shaped positive electrode component material, copper and aluminum are obtained through separation and recovery. Based on the principle that positive and negative binders have different properties and the characteristic of good ductility of a metal foil material, for a waste battery with low binder content (less than or equal to 6%) in a positive material, a mixture of a positive pole piece and a negative pole piece is stirred in a water environment and is matched with secondary sieving treatment, so that the positive and negative binders in the waste battery are uniformly mixed. Powdery negative electrode component materials, sheet-shaped positive electrode component materials, copper and aluminum can be recycled, and efficient separation and recycling of the positive electrode materials and the negative electrode materials and the current collector are achieved.

Description

technical field [0001] The invention belongs to the field of waste battery recycling, and more specifically relates to a method for comprehensively separating and recycling materials in decommissioned batteries, which can realize the comprehensive separation and recycling of materials related to positive pole pieces and negative pole pieces inside the battery. Background technique [0002] Lithium-ion batteries have high energy density and power density, and are widely used in consumer electronics, large-scale energy storage, electric vehicles, 5G and other fields. Electric vehicles are the development trend in the future, and the output and demand of the supporting power batteries are also increasing rapidly year by year. In addition to lithium-ion batteries, sodium-ion and other battery systems are also emerging and will occupy an important position in the future. The rapid development of power batteries also means that my country is about to face the retirement of a large...

AI Technical Summary

Problems solved by technology

The application number is 201610886130.9, and the title of the invention is "Method for Recovering Lithium Iron Phosphate from Waste Lithium Batteries". The positive electrode piece of lithium iron phosphate is soaked in the mixed solution of organic reagent and water, and the positive electrode material is assisted by ultrasound. The steps of the method are: Simple, but involves the use of organic reagents such as NMP (NMP plays a role in dissolving PVDF), NMP has reproductive system toxicity and will cause harm to human health

[0004] Chinese patent CN1758478A discloses a method for recovering positive and negative electrode materials from waste and old pole pieces. This patent uses two methods: high temperature method and specific gravity method. The high temperature method is to decompose the binder through high temperature to achieve the effect of separation. The specific gravity method separates the substrate fragments from the positive electrode powder by ball milling the pole pieces and sieving, then uses water to stir to remove the binder in the positive electrode powder, and then filters and pulverizes Sieve, although it also discloses stirring in water to remove PVDF, wherein the ball mill plays the main role of separating the active material and the current collector, and water plays an auxiliary role, there are still problems such as low purity and low yield of the positive electrode material after the ball mill is pulverized and separated

[0005] Chinese patent CN107282285A discloses a method for separating the positive and negative electrodes of a lithium-ion battery. The product is placed in a sodium bromide solution, and the density of the positive electrode active material and the current collector is different, and the liquid buoyancy is used for sorting. The method of separating the positive electrode current collector from the positive electrode material, but the separation of the positive electrode material from the positive electrode current collector still relies on crushing treatment, the solution only plays a role in sorting, and there are still problems such as the toxicity of lithium bromide solution

[0006] Chinese patent CN109904545A discloses a method for reclaiming separators, copper foils, positive electrode sheets, and negative active materials from waste lithium-ion power batteries, although it also discloses the use of aqueous solution Separation of the negative electrode active material and the current collector, but there is no recycling of the positive electrode material with the positive electrode binder, and there is still the problem of not realizing the separation of the positive electrode material and the positive electrode current collector

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