Method for separating and recycling waste lithium battery pole piece material

Abstract

The invention discloses a method for separating and recycling a waste lithium battery pole piece material, and belongs to the field of lithium battery recycling. The method for separating and recycling the waste lithium battery pole piece material comprises the following steps that: S1, a pole piece of a waste lithium battery is obtained, wherein the pole piece comprises a current collector and a coating layer formed on the surface of the current collector; and S2, an anode and a cathode are provided, a positive plate in the pole piece is taken as the anode, and / or a negative plate in the pole piece is taken as the cathode, in an alkaline electrolyte aqueous solution, the anode and the cathode are electrified to perform high-current pulse charge-discharge cycle treatment to electrolyze water, and then the anode and the cathode are soaked in an acidic aqueous solution, at least part of the coating layer on the pole piece is separated from the current collector, the current in the high-current pulse charge-discharge cycle treatment is 2-10 C, and the charge-discharge interval is 5-60 s. On the premise of simplifying the recovery process, the fluid and the coating can be effectively separated and recovered, the recovery and separation efficiency is high, and the purity of a final product is high.

Description

technical field [0001] This application relates to the field of lithium battery recycling, in particular, to a method for separating and recycling waste lithium battery pole piece materials. Background technique [0002] The high energy density, high rate performance, long cycle life, high working voltage and other advantages of lithium power batteries have become a new type of energy storage battery that is currently receiving much attention. At the same time, through the unremitting efforts of scientific researchers in the industry, the battery life has been doubled. Therefore, lithium batteries have become the preferred energy storage application batteries for electric vehicles. As various automobile giants accelerate the pace of electrification, the installed capacity of power batteries in the future will soared. The magnification of global demand for lithium battery materials has caused the price of key battery materials to skyrocket, pushing up the manufacturing costs...

AI Technical Summary

Problems solved by technology

[0007]CN108365286A proposes a method for stripping the anode current collector of a nickel-cobalt-manganese ternary lithium battery based on a supercritical liquid, including putting the anode material of a nickel-cobalt-manganese ternary lithium battery into In the reaction kettle, add a solvent to completely submerge the positive electrode material of the nickel-cobalt-manganese ternary lithium battery, with the aid of mechanical stirring, and use supercritical fluid to dissolve and strip the organic components in the positive electrode material under a certain humidity and pressure, which is difficult to recycle.

[0008] CN108736086A discloses a supercritical fluid extraction method to reclaim polyvinylidene fluoride, aluminum and positive electrode waste (active material and conductive carbon powder mixture) in the positive plate of lithium ion waste batteries ) method, this method does not use acid-base treatment electrodes, does not need high-temperature incineration, does not produce chemical waste liquid and toxic waste gas, and can be directly recycled as raw materials, but it is not easy to use on a large scale

[0009] In the CN111769340A patent invention, it is proposed to disassemble and dry the waste battery to obtain a dry positive electrode sheet, then mix the electrode sheet with deionized water, and conduct ultrasonic treatment at a frequency of 20-40KHz , and then treated at a low temperature of -30-50°C for 80-100 minutes, so long-term ultrasonic and low-temperature freezing treatment, and finally the coating layer on the positive electrode sheet of the waste battery can be separated from the current collector. This method does not add additional toxic and harmful chemical reagents. No toxic waste gas is produced during the treatment process, which is friendly to the environment, but the treatment time is too long, and excessive ultrasound will cause some aluminum foil to be crushed and mixed with the positive electrode active material, which consumes a lot of energy and has disadvantages

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