# US 2023/0056045 A1 · Cap Assembly, Secondary Battery Comprising the Same, and Battery Pack > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0056045 A1 - Document ID: US20230056045A1 - Status: Published application - Kind: A1 - Application number: 17/789,889 - Filed: 2021-02-03 - Published: 2023-02-23 - Earliest claimed: 2020-02-06 - Assignees: LG Energy Solution, Ltd. - Applicants: LG Energy Solution, Ltd. - Inventors: Jong In Son - Web page: https://patentgrep.com/patent/US20230056045A1 ## CPC - H01M 50/152: for cells having curved cross-section, e.g. round or elliptic (H01M50/15, H01M50/153 take precedence) - H01M 50/183: Sealing members - H01M 50/3425: {in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member} - H01M 50/533: characterised by the shape of the leads or tabs - H01M 50/578: in response to pressure - H01M 50/583: in response to current, e.g. fuses - H01M 50/186: characterised by the disposition of the sealing members - 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 relates to a secondary battery. The secondary battery comprises: an electrode assembly; a can configured to accommodate the electrode assembly; an electrolyte impregnated into the electrode assembly while being injected into the can; and a cap assembly mounted on an opening of the can, wherein the cap assembly comprises: a top cap in which a top hole is formed to pass vertically; a safety vent which is provided under the top cap and in which a vent hole is formed to pass vertically; and a current interrupt device (CID) filter which is provided under the safety vent, to which a positive electrode tab provided in the electrode assembly is coupled, and in which a CID hole is formed to pass vertically, wherein the CID hole is closed or opened by the positive electrode tab. ## Claims ### Claim 1 A secondary battery comprising: an electrode assembly; a can accommodating the electrode assembly therein, the can having a longitudinal axis extending in a vertical direction; an electrolyte impregnated into the electrode assembly within the can; and a cap assembly mounted on an opening of the can, wherein the cap assembly comprises: a top cap in which a top hole extends therethrough in the vertical direction; a safety vent which is provided under the top cap and in which a vent hole extends therethrough in the vertical direction; and a current interrupt device (CID) filter which is provided under the safety vent, to which a positive electrode tab of the electrode assembly is coupled, and in which a CID hole extends therethrough in the vertical direction, wherein the CID hole is configured to be closed or opened by movement of the positive electrode tab. ### Claim 2 (depends on 1) The secondary battery of claim 1, wherein, the top hole, the vent hole, and the CID hole are formed along a same line extending in the vertical direction, and the positive electrode tab, is visible from an outside of the secondary battery through the top hole, the vent hole, and the CID hole. ### Claim 3 (depends on 1) The secondary battery of claim 1, wherein the vent hole has a diameter greater than respective diameters of each of the top hole and the CID hole. ### Claim 4 (depends on 1) The secondary battery of claim 1, wherein the safety vent and the CID filter are coupled to each other, thereby connecting the vent hole to the CID hole. ### Claim 5 (depends on 4) The secondary battery of claim 4, wherein a gap between an outer circumferential surface of the vent hole and an outer circumferential surface of the CID hole, is sealed. ### Claim 6 (depends on 1) The secondary battery of claim 1, wherein the positive electrode tab comprises a lower tab part and an upper tab part, wherein the lower tab part is connected to the electrode assembly, and the upper tab part has a first end connected to both the lower tab part and the CID filter and a second end opposite the first end that is configured to be selectively in surface contact with or separated from a bottom surface of the CID filter to close or open the CID hole. ### Claim 7 (depends on 6) The secondary battery of claim 6, wherein the positive electrode tab is made of a material having an elastic restoring force so that the second end of the upper tab part is elastically in surface contact with the bottom surface of the CID filter. ### Claim 8 (depends on 6) The secondary battery of claim 6, wherein a lower end of an inner circumferential surface of the CID hole and the positive electrode tab configured to be selectively sealed to one another. ### Claim 9 (depends on 1) The secondary battery of claim 1, wherein the positive electrode tab comprises a sealing protrusion configured to be inserted into the CID hole to seal the CID hole. ### Claim 10 (depends on 9) The secondary battery of claim 9, wherein the sealing protrusion is formed as a hemispherical protrusion extending from a surface of the positive electrode tab. ### Claim 11 (depends on 4) The secondary battery of claim 4, further comprising a sealing ball disposed in the CID hole. ### Claim 12 (depends on 1) The secondary battery of claim 1, further comprising a closing cover coupled to the top hole, wherein the closing cover is made of a same material as the top cap. ### Claim 13 (depends on 1) A battery pack comprising: one or more secondary batteries each according to claim 1; and a battery case accommodating the one or more secondary batteries therein. ### Claim 14 A cap assembly configured to be mounted on an opening of a can accommodating an electrode assembly therein and having a longitudinal axis extending in a vertical direction, the cap assembly comprising: a top cap in which a top hole extends therethrough in the vertical direction; a safety vent which is provided under the top cap and in which a vent hole extends therethrough in the vertical direction; and a CID filter which is provided under the safety vent and in which a CID hole extends therethrough in the vertical direction. ### Claim 15 (depends on 14) The cap assembly of claim 14, wherein the top hole, the vent hole, and the CID hole are formed along a same line extending in the vertical direction.