# US 2021/0280844 A1 · Adhesive for lithium-ion electrode, electrode for lithium-ion battery and method for manufacturing electrode for lithium-ion battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0280844 A1 - Document ID: US20210280844A1 - Status: Published application - Kind: A1 - Application number: 16/605,639 - Filed: 2018-04-20 - Published: 2021-09-09 - Earliest claimed: 2017-04-21 - Assignees: Sanyo Chemical Industries, Ltd. - Applicants: Sanyo Chemical Industries, Ltd. - Inventors: Tomoya OHTA; Kotaro NASU; Kenichi KAWAKITA; Takuya SUENAGA; Yusuke MORI; Yasuhiko OHSAWA; Yuki KUSACHI; Hajime SATOU; Hiroshi AKAMA; Hideaki HORIE - Web page: https://patentgrep.com/patent/US20210280844A1 ## CPC - H01M 4/045: {Electrochemical coating; Electrochemical impregnation} - H01M 4/622: {being polymers} - H01M 4/043: {involving compressing or compaction} - H01M 4/13: Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof - H01M 4/139: Processes of manufacture - H01M 4/364: {as mixtures} - H01M 4/623: {fluorinated polymers} - H01M 10/052: Li-accumulators - H01M 4/366: {as layered products} - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract The present invention provides a viscous adhesive capable of retaining the shape of an electrode and allowing for production of an electrode for a lithium-ion battery having a structure in which the energy density of the electrode does not decrease. The present invention relates to a viscous adhesive for a lithium-ion electrode which allows active materials to adhere to each other in a lithium-ion electrode, the viscous adhesive having a glass transition temperature of 60° C. or lower, a solubility parameter of 8 to 13 (cal/cm3)1/2, and a storage shear modulus and a loss shear modulus of 2.0×103 to 5.0×107 Pa as measured in a frequency range of 10−1 to 101 Hz at 20° C., wherein the viscous adhesive is an acrylic polymer essentially containing a constituent unit derived from a (meth)acrylic acid alkyl ester monomer, the proportion of the (meth)acrylic acid alkyl ester monomer in monomers constituting the viscous adhesive is 50 wt % or more based on the total monomer weight, and the proportion of a fluorine-containing monomer is less than 3 wt % based on the total monomer weight. ## Claims ### Claim 1 A viscous adhesive for a lithium-ion electrode which allows active materials to adhere to each other in a lithium-ion electrode, the viscous adhesive having a glass transition temperature of 60° C. or lower, a solubility parameter of 8 to 13 (cal/cm3)1/2, and a storage shear modulus and a loss shear modulus of 2.0×103 to 5.0×107 Pa as measured in a frequency range of 10−1 to 101 Hz at 20° C., wherein the viscous adhesive is an acrylic polymer essentially containing a constituent unit derived from a (meth)acrylic acid alkyl ester monomer, the proportion of the (meth)acrylic acid alkyl ester monomer in monomers constituting the viscous adhesive is 50 wt % or more based on the total monomer weight, and the proportion of a fluorine-containing monomer is less than 3 wt % based on the total monomer weight. ### Claim 2 (depends on 1) The viscous adhesive for a lithium-ion electrode according to claim 1, wherein the viscous adhesive contains two or more (meth)acrylic acid alkyl ester monomers as constituent monomers, and the total content of these monomers is 50 wt % or more based on the total constituent monomer weight. ### Claim 3 (depends on 1) The viscous adhesive for a lithium-ion electrode according to claim 1, wherein the viscous adhesive contains, as a constituent monomer, a monovinyl monomer copolymerizable with the (meth)acrylic acid alkyl ester monomer. ### Claim 4 (depends on 1) The viscous adhesive for a lithium-ion electrode according to claim 1, wherein the viscous adhesive contains a (meth)acrylic acid monomer as a constituent monomer. ### Claim 5 (depends on 1) An electrode for a lithium-ion battery comprising: an unbound product between the viscous adhesive according to claim 1 and a coated electrode active material including an electrode active material that occludes and releases lithium ions and a coating layer containing a coating resin on at least a portion of a surface of the electrode active material. ### Claim 6 (depends on 5) The electrode for a lithium-ion battery according to claim 5, wherein the weight ratio of the coated electrode active material to the viscous adhesive (coated electrode active material/viscous adhesive) is 90/10 to 99.99/0.01. ### Claim 7 (depends on 5) The electrode for a lithium-ion battery according to claim 5, wherein an electrode active material layer constituting the electrode has a thickness of 150 μm or more. ### Claim 8 A method of producing an electrode for a lithium-ion battery, comprising: compressing a mixture of a coated electrode active material and a viscous adhesive for a lithium-ion electrode so as to form an electrode active material layer formed from an unbound product of the mixture containing the coated electrode active material and the viscous adhesive, the coated electrode active material including an electrode active material that occludes and releases lithium ions and a coating layer containing a coating resin on at least a portion of a surface of the electrode active material, the viscous adhesive for a lithium-ion electrode being a viscous adhesive that allows active materials to adhere to each other in a lithium-ion electrode, the viscous adhesive having a glass transition temperature of 60° C. or lower, a solubility parameter of 8 to 13 (cal/cm3)1/2, and a storage shear modulus and a loss shear modulus of 2.0×103 to 5.0×107 Pa as measured in a frequency range of 10−1 to 101 Hz at 20° C., wherein the viscous adhesive is an acrylic polymer essentially containing a constituent unit derived from a (meth)acrylic acid alkyl ester monomer, the proportion of the (meth)acrylic acid alkyl ester monomer in monomers constituting the viscous adhesive is 50 wt % or more based on the total monomer weight, and the proportion of a fluorine-containing monomer is less than 3 wt % based on the total monomer weight. ### Claim 9 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the viscous adhesive contains two or more (meth)acrylic acid alkyl ester monomers as constituent monomers, and the total content of these monomers is 50 wt % or more based on the total constituent monomer weight. ### Claim 10 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the viscous adhesive contains, as a constituent monomer, a monovinyl monomer copolymerizable with the (meth)acrylic acid alkyl ester monomer. ### Claim 11 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the viscous adhesive contains a (meth)acrylic acid monomer as a constituent monomer. ### Claim 12 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the weight ratio of the coated electrode active material to the viscous adhesive (coated electrode active material/viscous adhesive) in the mixture is 90/10 to 99.99/0.01. ### Claim 13 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the mixture is an electrolyte solution-containing mixture further containing an electrolyte solution, and the electrode active material layer is formed by compressing the electrolyte solution-containing mixture. ### Claim 14 (depends on 8) The method of producing an electrode for a lithium-ion battery according to claim 8, wherein the electrode active material layer has a thickness of 150 μm or more.