# US 12,002,999 B2 · 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 12,002,999 B2 - Document ID: US12002999B2 - Status: Granted - Kind: B2 - Application number: 17/287,078 - Filed: 2019-10-23 - Published: 2021-11-18 - Granted: 2024-06-04 - Earliest claimed: 2018-10-26 - Assignees: GS Yuasa International Ltd. - Applicants: GS Yuasa International Ltd. - Inventors: Hironori Ichinohashi - Web page: https://patentgrep.com/patent/US12002999B2 ## CPC - H01G 11/76: specially adapted for integration in multiple or stacked hybrid or EDL capacitors - H01M 50/545: formed by the casing of the cells (cup shaped terminals adapted for cells having curved cross-section H01M50/56) - H01G 11/72: specially adapted for integration in multiple or stacked hybrid or EDL capacitors - 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 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 50/103: prismatic or rectangular (H01M50/109, H01M50/11 take precedence) - H01M 50/15: for prismatic or rectangular cells (H01M50/153 takes precedence) - H01M 50/176: for prismatic or rectangular cells (H01M50/181 takes precedence) - H01M 50/533: characterised by the shape of the leads or tabs - H01M 50/534: characterised by the material of the leads or tabs - H01M 50/531: Electrode connections inside a battery casing - H01M 50/536: characterised by the method of fixing the leads to the electrodes, e.g. by welding - H01M 2220/20: Batteries in motive systems, e.g. vehicle, ship, plane - Y02E 60/10: Energy storage using batteries - Y02T 10/70: Energy storage systems for electromobility, e.g. 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 - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An energy storage device includes a case, an electrode assembly housed in the case, a current collector arranged between the electrode assembly and a lid of the case in Z-axis direction, and an electrode terminal fixed to the lid. The current collector has a terminal connecting portion connected to the electrode terminal and an electrode connecting portion connected to the electrode assembly. The terminal connecting portion and the electrode connecting portion are arranged side by side in X-axis direction intersecting with the Z-axis direction, and a thickness of the electrode connecting portion is smaller than a thickness of the terminal connecting portion. ## Claims ### Claim 1 An energy storage device including a case and an electrode assembly housed in the case, the energy storage device comprising: a current collector arranged between the electrode assembly and a wall of the case in a first direction; and an electrode terminal fixed to the wall, wherein the current collector includes: a terminal connecting portion connected to the electrode terminal; and an electrode connecting portion connected to the electrode assembly, wherein the terminal connecting portion and the electrode connecting portion are arranged side by side in a second direction intersecting with the first direction, wherein a thickness of the electrode connecting portion is smaller than a thickness of the terminal connecting portion, wherein the electrode assembly includes an electrode assembly body portion and a tab portion protruding from a part of the electrode assembly body portion in the first direction, wherein the electrode assembly includes a positive electrode plate and a negative electrode plate, wherein the tab portion is disposed between the electrode assembly body portion and the wall in the first direction, wherein the tab portion includes a plurality of tabs on the positive electrode plate and a plurality of tabs on the negative electrode plate, and wherein the plurality of tabs on the positive electrode plate and the plurality of tabs on the negative electrode plate protrude toward the wall. ### Claim 2 (depends on 1) The energy storage device according to claim 1, wherein a width of the electrode connecting portion in a third direction intersecting with the first direction and the second direction is larger than a width of the terminal connecting portion in the third direction. ### Claim 3 (depends on 2) The energy storage device according to claim 2, wherein an area of a cross section of the electrode connecting portion orthogonal to the second direction is equal to or larger than an area of a cross section of the terminal connecting portion orthogonal to the second direction. ### Claim 4 (depends on 2) The energy storage device according to claim 2, wherein the current collector further has an intermediate portion that connects the terminal connecting portion and the electrode connecting portion, and wherein the intermediate portion is formed to be smaller in thickness and larger in width in the third direction as it approaches from the terminal connecting portion to the electrode connecting portion. ### Claim 5 (depends on 1) The energy storage device according to claim 1, wherein an end portion of the electrode connecting portion in the third direction intersecting with the first direction and the second direction is bent toward the electrode assembly. ### Claim 6 (depends on 1) The energy storage device according to claim 1, wherein a surface of the current collector facing the wall is flat, and wherein a step is formed on a surface of the current collector facing the electrode assembly due to difference in thickness between the terminal connecting portion and the electrode connecting portion. ### Claim 7 (depends on 1) The energy storage device according to claim 1, wherein the electrode connecting portion is disposed between the electrode assembly and the wall in the first direction. ### Claim 8 (depends on 1) The energy storage device according to claim 1, wherein the current collector, the electrode assembly and the wall are arranged along the first direction. ### Claim 9 (depends on 1) The energy storage device according to claim 1, wherein the tab portion of the electrode assembly extends in a third direction intersecting with the first direction and the second direction. ### Claim 10 (depends on 1) The energy storage device according to claim 1, wherein the electrode assembly includes an oval cross-sectional shape. ### Claim 11 (depends on 1) The energy storage device according to claim 1, wherein the electrode assembly includes an elliptical cross-sectional shape. ### Claim 12 (depends on 1) The energy storage device according to claim 1, wherein a cross-sectional area of the electrode connecting portion is less than a cross-sectional area of the terminal connecting portion. ### Claim 13 (depends on 1) The energy storage device according to claim 1, wherein an area of a cross section of the electrode connecting portion orthogonal to the second direction is made equal to or more than an area of a cross section of the terminal connecting portion orthogonal to the second direction. ### Claim 14 (depends on 1) The energy storage device according to claim 1, wherein the current collector further includes an intermediate portion that connects the terminal connecting portion and the electrode connecting portion that each have different thicknesses and widths. ### Claim 15 (depends on 14) The energy storage device according to claim 14, wherein the intermediate portion has a cross-sectional area that is substantially constant at a portion where the terminal connecting portion and the electrode connecting portion are connected.