# US 11,114,729 B2 · Energy storage device and method of manufacturing energy storage device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,114,729 B2 - Document ID: US11114729B2 - Status: Granted - Kind: B2 - Application number: 15/761,464 - Filed: 2016-09-27 - Published: 2018-11-29 - Granted: 2021-09-07 - Earliest claimed: 2015-09-29 - Assignees: GS Yuasa International Ltd. - Applicants: GS Yuasa International Ltd. - Inventors: Hirokazu Kambayashi; Kazuto Maeda - Web page: https://patentgrep.com/patent/US11114729B2 ## CPC - H01G 9/04: Electrodes {or formation of dielectric layers thereon} - H01G 9/0029: {Processes of manufacture} - H01G 9/008: Terminals - H01G 11/10: Multiple hybrid or EDL capacitors, e.g. arrays or modules (housings, cases, encapsulations or mountings thereof H01G11/78) - H01G 11/72: specially adapted for integration in multiple or stacked hybrid or EDL capacitors - H01G 11/76: specially adapted for integration in multiple or stacked hybrid or EDL capacitors - H01G 11/80: Gaskets; Sealings - H01G 11/82: Fixing or assembling a capacitive element in a housing, e.g. mounting electrodes, current collectors or terminals in containers or encapsulations - H01M 50/528: Fixed electrical connections, i.e. not intended for disconnection - H01M 50/533: characterised by the shape of the leads or tabs - H01M 50/536: characterised by the method of fixing the leads to the electrodes, e.g. by welding - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 50/538: Connection of several leads or tabs of wound or folded electrode stacks - Y02E 60/10: Energy storage using batteries - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) - 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 An energy storage device including: an electrode assembly and a positive electrode current collector, wherein the positive electrode current collector includes an electrode connecting portion connected to the electrode assembly, the electrode connecting portion includes a first portion and a second portion which has a smaller wall thickness than the first portion and is joined to the electrode assembly, and either one of the second portion or the electrode assembly includes a first convex portion projecting toward the other in a joined portion. ## Claims ### Claim 1 An energy storage device, comprising: an electrode assembly which includes an electrode converged portion; and a current collector, wherein the electrode converged portion includes converged current collecting foils stacked in a stacking direction, wherein the current collector includes an electrode connecting portion connected to the electrode converged portion, wherein the electrode connecting portion includes a first portion and a second portion which has a smaller wall thickness than the first portion and is joined to the electrode assembly, wherein one of the second portion and the electrode converged portion includes a first convex portion projecting toward another of the second portion and the electrode converged portion in a joined portion in the stacking direction, and wherein the another of the second portion and the electrode converged portion includes a second convex portion that projects from the another of the second portion and the electrode converged portion away from the one of the second portion and the electrode converged portion in the stacking direction. ### Claim 2 (depends on 1) The energy storage device according to claim 1, wherein the current collector further includes a terminal connecting portion connected to an electrode terminal, and wherein at least a portion of the first portion is disposed between the terminal connecting portion and the second portion. ### Claim 3 (depends on 1) The energy storage device according to claim 1, wherein the electrode connecting portion includes a plurality of the second portions, and wherein at least a portion of the first portion is disposed between the plurality of the second portions. ### Claim 4 (depends on 1) The energy storage device according to claim 1, wherein at least a portion of the first portion is disposed on a periphery of the second portion. ### Claim 5 (depends on 1) The energy storage device according to claim 1, further comprising a cover member disposed at a position where the cover member sandwiches the electrode assembly in cooperation with the electrode connecting portion, wherein the cover member includes a first cover portion and a second cover portion which has a smaller wall thickness than the first cover portion and is joined to the electrode assembly. ### Claim 6 (depends on 1) The energy storage device according to claim 1, further comprising a cover member disposed at a position where the cover member and the electrode connecting portion sandwich the electrode assembly. ### Claim 7 (depends on 6) The energy storage device according to claim 6, wherein the cover member is disposed on a surface of the electrode converged portion. ### Claim 8 (depends on 6) The energy storage device according to claim 6, wherein, in a projecting direction of the first convex portion toward said another of the second portion and the electrode assembly, the cover member is disposed on the surface of the electrode converged portion. ### Claim 9 (depends on 8) The energy storage device according to claim 8, wherein, in the projecting direction of the first convex portion toward said another of the second portion and the electrode assembly, the electrode connecting portion is disposed on another surface of the electrode converged portion. ### Claim 10 (depends on 1) The energy storage device according to claim 1, wherein the current collector further includes a terminal connecting portion connecting opposing sides of the first portion that are disposed on opposing sides of the electrode assembly, respectively. ### Claim 11 (depends on 10) The energy storage device according to claim 10, wherein the terminal connecting portion is disposed on a surface of the electrode converged portion that extends between the opposing sides of the electrode assembly. ### Claim 12 (depends on 10) The energy storage device according to claim 10, wherein the first portion is disposed between the second portion and the terminal connecting portion. ### Claim 13 (depends on 1) The energy storage device according to claim 1, wherein, in a longitudinal direction of an extension of the electrode connecting portion, the second portion is disposed between opposing sides of the first portion. ### Claim 14 (depends on 13) The energy storage device according to claim 13, wherein, in the longitudinal direction of the extension of the electrode connecting portion, the first convex portion is disposed between opposing sides of the second portion. ### Claim 15 An energy storage device, comprising: an electrode assembly including converged current collecting foils stacked in a stacking direction; a current collector including an electrode connecting portion connected to the electrode assembly; and a cover member disposed at a position where the cover member and the electrode connecting portion sandwich the electrode assembly, wherein the electrode connecting portion includes a first portion and a second portion which has a smaller wall thickness than the first portion and is joined to the electrode assembly, wherein one of the second portion and the electrode assembly includes a first convex portion projecting toward another of the second portion and the electrode assembly in a joined portion in the stacking direction, wherein the another of the second portion and the electrode assembly includes a second convex portion that projects from the another of the second portion and the electrode assembly away from the one of the second portion and the electrode assembly in the stacking direction, and wherein the cover member includes a first cover portion and a second cover portion which has a smaller wall thickness than the first cover portion and is joined to the electrode assembly. ### Claim 16 (depends on 15) The energy storage device according to claim 15, wherein, in a projecting direction of the first convex portion toward said another of the second portion and the electrode assembly, the cover member is disposed on a surface of the electrode assembly. ### Claim 17 (depends on 16) The energy storage device according to claim 16, wherein, in the projecting direction of the first convex portion toward said another of the second portion and the electrode assembly, the electrode connecting portion is disposed on another surface of the electrode assembly. ### Claim 18 (depends on 15) The energy storage device according to claim 15, wherein the current collector further includes a terminal connecting portion connecting opposing sides of the first portion that are disposed on opposing sides of the electrode assembly, respectively. ### Claim 19 (depends on 15) The energy storage device according to claim 15, wherein, in a longitudinal direction of an extension of the electrode connecting portion, the second portion is disposed between opposing sides of the first portion. ### Claim 20 A method of manufacturing an energy storage device including an electrode assembly which includes an electrode converged portion, and a current collector including an electrode connecting portion connected to the electrode converged portion, the method comprising: forming a thin wall thickness portion having a smaller wall thickness than another portion on the electrode connecting portion; and joining the thin wall thickness portion and the electrode assembly to each other by plastic deformation, wherein the electrode converged portion is formed by converging current collecting foils stacked in a stacking direction, wherein one of the thin wall thickness portion and the electrode converged portion includes a first convex portion projecting toward another of the thin wall thickness portion and the electrode converged portion in a joined portion in the stacking direction, and wherein the another of the thin wall thickness portion and the electrode converged portion includes a second convex portion that projects from the another of the thin wall thickness portion and the electrode converged portion away from the one of the thin wall thickness portion and the electrode converged portion in the stacking direction.