Physical purification method for recycling positive powder from lithium ion battery

Abstract

The invention relates to a physical purification method for recycling a positive powder from a lithium ion battery, and belongs to the technical field of recycling of lithium ion batteries. The physical purification method for recycling the positive powder from the lithium ion battery comprises the steps of performing first magnetic separation on the positive powder obtained by recycling by employing a magnetic field with magnetic induction intensity being 2,500-3,500Gs, removing a selected substance, performing second magnetic separation on remaining powder by employing a magnetic field withmagnetic induction intensity larger than 7,000Gs, and electing a separated substance, thereby obtaining the positive powder, wherein the positive material of the lithium ion battery contains at leastone element of cobalt, manganese, iron and nickel. The purification method is simple in process, low in equipment investment, low in cost and wide in adaptability, the positive powder with purity reaching 96% or above can be obtained by magnetic separation of a weak magnetic field in one time, and meanwhile, the aluminum recycle rate also can be improved.

Description

technical field [0001] The invention relates to a physical purification method for recovering positive electrode powder from a lithium ion battery, 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 recycling 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. Therefore, the recycling of used lithium-ion batteries is of great significance. [0003] Since more ...

AI Technical Summary

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. 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.

If you want to obtain a higher purity positive electrode powder, you need to use a finer screen for sieving. In this case, the purity of the positive electrode powder can also reach more than 98%, but the finer the screen for the positive electrode powder The material is sieved, and a large number of positive electrode powder particles with larger particle sizes are mixed into the aluminum particles, which greatly reduces the purity of the recovered aluminum and the effective recovery rate of the positive electrode powder.

In addition, in the process of recycling the positive electrode powder, it is inevitable that the iron that has been worn off by the equipment will be brought into the positive electrode powder, which further increases the difficulty of separating the positive electrode powder by physical methods. How to ensure the effective use of the positive electrode powder In the case of low recovery rate, further improving the purity of the positive electrode powder recovered by physical methods has become an urgent problem to be solved.

Images