Separation method for cathode and anode plates in recovery process of lithium ion batteries

Abstract

The invention relates to a separation method for cathode and anode plates in a recovery process of lithium ion batteries and belongs to the technical field of recovery of lithium ion batteries. The separation method includes the steps of: performing magnetic separation to mixed chips, which are composed of cathode chips and anode chips and are formed during the recovery process of lithium ion batteries, in a magnetic field, of which the magnetic inductive intensity is higher than 9000 Gs, thus separating the cathode chips out, wherein a cathode material of the cathode chips includes at least one of cobalt, manganese, iron and nickel. The separation method is simple and high-effective, is low in recovery cost and is free of generation of pollutants. Through the separation method, the separation rate of the cathode chips can reach more than 95% through one-stage magnetic separation and can reach more than 98% through more than two stages of magnetic separation. The method can significantly increase the recovery rate and recovery purity of cathode and anode powders and copper and aluminum granules in subsequent steps.

Description

technical field [0001] The invention relates to a method for separating positive and negative plates in the recovery process of lithium ion batteries, and belongs to the technical field of lithium ion battery recovery. Background technique [0002] With the country's vigorous promotion of electric vehicles, a large number of power lithium batteries will be scrapped in the future. According to the prediction of China Automotive Technology Research Center, the recovery rate of waste batteries in my country will be less than 2% in the future. Waste lithium-ion batteries contain reusable resources, such as valuable metals such as aluminum and copper, graphite, and positive electrode materials, as well as a large amount of electrolyte solution; if these waste lithium batteries are not handled properly, it will cause a great waste of resources. and serious environmental pollution. [0003] In the prior art, the main valuable recycled materials for lithium-ion batteries are copper...

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Problems solved by technology

[0002] With the country's vigorous promotion of electric vehicles, a large number of power lithium batteries will be scrapped in the future, and according to the prediction of China Automotive Technology Research Center, the recovery rate of waste batteries in my country will be less than 2% in the future

Waste lithium-ion batteries contain reusable resources, such as valuable metals such as aluminum and copper, graphite, and positive electrode materials, as well as a large amount of electrolyte solution; if these waste lithium batteries are not handled properly, it will cause a great waste of resources. and severe environmental pollution

[0003] In the prior art, the main valuable recycled materials for lithium-ion batteries are copper, aluminum, positive electrode powder and negative electrode powder, and more than 90% of the valuable recycled materials are on the positive and negative electrodes of lithium-ion batteries. The positive electrode sheet is aluminum foil coated with positive electrode material, and the negative electrode sheet of lithium ion battery is copper foil coated with negative electrode material; how to realize the efficient recovery of valuable materials under the premise of ensuring the purity of recycled materials has become the key to the recycling technology of waste lithium batteries; the existing technology There are two recycling methods: one is to remove the battery casing, and then separate the positive and negative electrodes manually or with complex mechanical equipment. After the separated negative and positive electrodes are separated, they are crushed and powdered, and the copper and negative electrodes are separated by air separation. And aluminum and positive electrode powder, the efficiency of the positive and negative plate separation method is particularly low, not suitable for mass production; the second is to crush the lithium-ion battery as a whole without dismantling the shell to make powder, and then separate the mixture of copper and aluminum and the positive electrode powder , a mixture of negative electrode powder, but it is difficult to separate the mixture of copper and aluminum from the mixture of positive and negative electrode powder, and the purity of the material cannot be guaranteed

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