Method for recycling battery electrodes

Patent metadata

Field	Value
Publication number	US-2023299372-A1
Application number	US-202118007753-A
Country	US
Kind code	A1
Filing date	Jun 16, 2021
Priority date	Jun 17, 2020
Publication date	Sep 21, 2023
Grant date	—

Abstract

Provided is a method for recycling a battery electrode by immersing the electrode into a delamination solution and subsequently precipitating a polymeric binder with the addition of a precipitation agent; wherein the electrode comprises a current collector and an electrode layer material coated on one side or both sides of the current collector; wherein the electrode layer material comprises a polymeric binder; and wherein the polymeric binder comprises a copolymer comprising a structural unit derived from an acid group-containing monomer and a structural unit derived from a hydrogen bond-forming group-containing monomer (ii). The method disclosed herein circumvents complex separation process, corrosion of current collector and contamination of polymeric binder, enables excellent materials recovery and allows the recycling of battery electrode to be achieved in a highly efficient manner.

First claim

What is claimed is:

1 . A method for recycling a battery electrode, comprising the steps of:
a) immersing an electrode, comprising a current collector and an electrode layer material coated on one side or both sides of the current collector, into a delamination solution to form a heterogeneous mixture; b) screening the heterogeneous mixture to separate the current collector and the electrode layer material from the delamination solution; c) adding the electrode layer material and a precipitation agent into an aqueous solvent to form a first suspension; wherein the electrode layer material comprises a polymeric binder and an electrode active material; and wherein the polymeric binder comprises a copolymer comprising a structural unit derived from an acid group-containing monomer and a structural unit derived from a hydrogen bond-forming group-containing monomer (ii).

2 . The method of claim 1 , wherein the copolymer further comprises a structural unit derived from a hydrogen bond-forming group-containing monomer (i); wherein the hydrogen bond-forming group-containing monomer (i) is selected from the group consisting of an amide group-containing monomer, a hydroxyl group-containing monomer and combinations thereof; and wherein the hydrogen bond-forming group-containing monomer (ii) is selected from the group consisting of a nitrile group-containing monomer, an ester group-containing monomer, an epoxy group-containing monomer, a fluorine group-containing monomer and combinations thereof.

3 . The method of claim 1 , wherein the molar ratio of the structural unit derived from an acid group-containing monomer to the structural unit derived from a hydrogen bond-forming group-containing monomer (ii) in the copolymer is from about 0.1 to about 5; and wherein the proportion of the structural unit derived from a hydrogen bond-forming group-containing monomer (ii) is from about 5% to about 85% by mole, based on the total number of moles of monomeric units in the copolymer in the polymeric binder.

4 . The method of claim 1 , wherein the current collector is in the form of a foil, sheet, film or a combination thereof; and wherein the current collector is selected from the group consisting of stainless steel, titanium, nickel, aluminum, copper, platinum, gold, silver, chromium, zirconium, tungsten, molybdenum, silicon, tin, vanadium, zinc, cadmium, or alloys thereof, electrically-conductive resin and combinations thereof.

5 . The method of claim 1 , wherein the acid group-containing monomer is selected from the group consisting of a carboxylic acid group-containing monomer, a sulfonic acid group-containing monomer, a phosphonic acid group-containing monomer and combinations thereof; and wherein the pK a of the acid group-containing monomer is at least 0.1 pH unit above the pK a of the precipitation agent.

6 . The method of claim 5 , wherein the carboxylic acid group-containing monomer is selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, 2-butyl crotonic acid, cinnamic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, 4,4-dimethyl itaconic acid, 2-ethylacrylic acid, isocrotonic acid, cis-2-pentenoic acid, trans-2-pentenoic acid, angelic acid, tiglic acid, 3,3-dimethyl acrylic acid, 3-propyl acrylic acid, trans-2-methyl-3-ethyl acrylic acid, cis-2-methyl-3-ethyl acrylic acid, 3-isopropyl acrylic acid, trans-3-methyl-3-ethyl acrylic acid, cis-3-methyl-3-ethyl acrylic acid, 2-isopropyl acrylic acid, trimethyl acrylic acid, 2-methyl-3,3-diethyl acrylic acid, 3-butyl acrylic acid, 2-butyl acrylic acid, 2-pentyl acrylic acid, 2-methyl-2-hexenoic acid, trans-3-methyl-2-hexenoic acid, 3-methyl-3-propyl acrylic acid, 2-ethyl-3-propyl acrylic acid, 2,3-diethyl acrylic acid, 3,3-diethyl acrylic acid, 3-methyl-3-hexyl acrylic acid, 3-methyl-3-tert-butyl acrylic acid, 2-methyl-3-pentyl acrylic acid, 3-methyl-3-pentyl acrylic acid, 4-methyl-2-hexenoic acid, 4-ethyl-2-hexenoic acid, 3-methyl-2-ethyl-2-hexenoic acid, 3-tert-butyl acrylic acid, 2,3-dimethyl-3-ethyl acrylic acid, 3,3-dimethyl-2-ethyl acrylic acid, 3-methyl-3-isopropyl acrylic acid, 2-methyl-3-isopropyl acrylic acid, trans-2-octenoic acid, cis-2-octenoic acid, trans-2-decenoic acid, α-acetoxyacrylic acid, β-trans-aryloxyacrylic acid, α-chloro-β-E-methoxyacrylic acid, methyl maleic acid, dimethyl maleic acid, phenyl maleic acid, bromo maleic acid, chloromaleic acid, dichloromaleic acid, fluoromaleic acid, difluoro maleic acid, nonyl hydrogen maleate, decyl hydrogen maleate, dodecyl hydrogen maleate, octadecyl hydrogen maleate, fluoroalkyl hydrogen maleate, maleic anhydride, methyl maleic anhydride, dimethyl maleic anhydride, acrylic anhydride, methacrylic anhydride, methacrolein, methacryloyl chloride, methacryloyl fluoride, methacryloyl bromide and combinations thereof.

7 . The method of claim 5 , wherein the sulfonic acid group-containing monomer is selected from the group consisting of vinylsulfonic acid, methylvinylsulfonic acid, allylvinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 2-sulfoethyl methacrylic acid, 2-methylprop-2-ene-1-sulfonic acid, 2-acrylamido-2-methyl-1-propane sulfonic acid, 3-allyloxy-2-hydroxy-1-propane sulfonic acid and combinations thereof.

8 . The method of claim 5 , wherein the phosphonic acid group-containing monomer is selected from the group consisting of vinyl phosphonic acid, allyl phosphonic acid, vinyl benzyl phosphonic acid, acrylamide alkyl phosphonic acid, methacrylamide alkyl phosphonic acid, acrylamide alkyl diphosphonic acid, acryloylphosphonic acid, 2-methacryloyloxyethyl phosphonic acid, bis(2-methacryloyloxyethyl) phosphonic acid, ethylene 2-methacryloyloxyethyl phosphonic acid, ethyl-methacryloyloxyethyl phosphonic acid and combinations thereof.

9 . The method of claim 1 , wherein the proportion of structural unit derived from an acid group-containing monomer is from about 5% to about 85% by mole, based on the total number moles of monomeric units in the copolymer in the polymeric binder.

10 . The method of claim 2 , wherein the nitrile group-containing monomer is selected from the group consisting of acrylonitrile, α-halogenoacrylonitrile, α-alkylacrylonitrile, α-chloroacrylonitrile, α-bromoacrylonitrile, α-fluoroacrylonitrile, methacrylonitrile, α-ethylacrylonitrile, α-isopropylacrylonitrile, α-n-hexylacrylonitrile, α-methoxyacrylonitrile, 3-methoxyacrylonitrile, 3-ethoxyacrylonitrile, α-acetoxyacrylonitrile, α-phenylacrylonitrile, α-tolylacrylonitrile, α-(methoxyphenyl)acrylonitrile, α-(chlorophenyl)acrylonitrile, α-(cyanophenyl)acrylonitrile, vinylidene cyanide and combinations thereof; and wherein the proportion of structural unit derived from a nitrile group-containing monomer is from about 5% to about 85% by mole, based on the total number moles of monomeric units in the copolymer in the polymeric binder.

11 . The method of claim 2 , wherein the amide group-containing monomer is selected from the group consisting of acrylamide, methacrylamide, N-methyl methacrylamide, N-ethyl methacrylamide, N-n-propyl methacrylamide, N-isopropyl methacrylamide, isopropyl acrylamide, N-n-butyl methacrylamide, N-isobutyl methacrylamide, N,N-dimethyl acrylamide, N,N-dimethyl methacrylamide, N,N-diethyl acrylamide, N,N-diethyl methacrylamide, N-methylol methacrylamide, N-(methoxymethyl)methacrylamide, N-(ethoxymethyl)methacrylamide, N-(propoxymethyl)methacrylamide, N-(butoxymethyl)methacrylamide, N,N-dimethylaminopropyl methacrylamide, N,N-dimethylaminoethyl methacrylamide, N,N-dimethylol methacrylamide, diacetone methacrylamide, diacetone acrylamide, methacryloyl morpholine, N-hydroxyl methacrylamide, N-methoxymethyl acrylam

Assignees

• Grst Int Ltd

Inventors

• Ho Kam Piu
• Jiang Yingkai
• Dong Yangjian

Classifications

• B29L2031/3468

  Batteries, accumulators or fuel cells (battery cases B29L2031/7146) · CPC title

• B29B2017/0293

  Dissolving the materials in gases or liquids · CPC title

• C08J3/16

  by coagulating dispersions {(C08J3/122 takes precedence)} · CPC title

• H01M4/667

  in the form of layers, e.g. coatings · CPC title

• C22B7/006

  Wet processes · CPC title