# US 12,119,503 B2 · Cap assembly and secondary battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,119,503 B2 - Document ID: US12119503B2 - Status: Granted - Kind: B2 - Application number: 18/237,902 - Filed: 2023-08-25 - Published: 2023-12-21 - Granted: 2024-10-15 - Earliest claimed: 2018-09-19 - Assignees: Contemporary Amperex Technology (Hong Kong) Limited - Applicants: Contemporary Amperex Technology Co., Limited - Inventors: Fenggang Zhao; Yuqun Zeng; Jian Guo; Quankun Li; Peng Wang - Web page: https://patentgrep.com/patent/US12119503B2 ## CPC - H01M 50/148: characterised by their shape - H01M 50/176: for prismatic or rectangular cells (H01M50/181 takes precedence) - H01M 50/55: on the same side of the cell - H01M 50/553: Terminals adapted for prismatic, pouch or rectangular cells - H01M 50/588: outside the batteries, e.g. incorrect connections of terminals or busbars - H01M 50/593: Spacers; Insulating plates - 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 disclosure relates to a cap assembly and a secondary battery. The cap assembly includes a cap plate provided with an electrode lead-out hole; an electrode terminal, covering the electrode lead-out hole and including a main body, wherein the main body is provided with a recess on a side wall; an isolating member including a receiving portion, wherein the main body is received in the receiving portion; and a protrusion, connected to an inner wall of the isolating member and extending towards an axis of the electrode lead-out hole, wherein the protrusion is received in the recess so as to prevent the main body from rotating relative to the isolating member. The cap assembly according to the embodiments of the present application can improve an overcurrent capacity and stability of the electrode terminal. ## Claims ### Claim 1 A secondary battery, comprising: a case provided with an opening; an electrode assembly accommodated in the case; and, a cap assembly, comprising: a cap plate, provided with an electrode lead-out hole; an electrode terminal, covering the electrode lead-out hole and comprising a main body, wherein the main body is located on a side of the cap plate facing away from an inner side of the secondary battery and provided with a recess on a side wall; an isolating member located on the side of the cap plate facing away from the inner side of the secondary battery and comprising a receiving portion, wherein the main body is received in the receiving portion; and a protrusion, connected to an inner wall of the isolating member and extending towards an axis of the electrode lead-out hole, wherein the protrusion is received in the recess so as to prevent the main body from rotating relative to the isolating member, wherein the cap assembly is configured to cover the opening to close the case with the electrode assembly therein, wherein the main body is provided with a plurality of recesses spaced apart from each other on the side wall, and the number of the protrusions is equal to the number of the recesses, and the cap assembly further comprises: a sealing member, which is located on the side of the cap plate facing away from the inner side of the secondary battery and is disposed between the cap plate and the main body of the electrode terminal to keep sealing between them, and a connecting piece for electrically connecting the electrode terminal with the electrode assembly, the connecting piece comprises a protruding portion, which extends into the electrode lead-out hole from the inner side of the secondary battery and is connected with the electrode terminal. ### Claim 2 (depends on 1) The secondary battery according to claim 1, wherein the recess is configured to extend through the main body in a thickness direction. ### Claim 3 (depends on 1) The secondary battery according to claim 1, wherein the main body is formed in a cylindrical shape. ### Claim 4 (depends on 1) The secondary battery according to claim 1, wherein the isolating member and the protrusion are integrally formed and are made of the same material. ### Claim 5 (depends on 1) The secondary battery according to claim 1, wherein the electrode terminal further comprises an external connection portion, which is located on a side of the main body facing away from the cap plate, and the main body extends beyond a peripheral surface of the external connection portion. ### Claim 6 (depends on 1) The secondary battery according to claim 1, wherein the isolating member is in contact with the main body, and in a thickness direction, a part of the isolating member is located on a side of the main body facing away from the cap plate so as to prevent the main body from moving in a direction away from the cap plate. ### Claim 7 (depends on 1) The secondary battery according to claim 1, wherein the cap assembly further comprises a connecting member, which is fixedly connected with the cap plate and is isolated from the main body through the isolating member, the connecting member comprises a first connecting portion located on a side of the main body facing away from the cap plate, and a part of the isolating member is located between the first connecting portion and the cap plate. ### Claim 8 (depends on 7) The secondary battery according to claim 7, wherein the connecting member further comprises an intermediate transition portion and a second connecting portion, the intermediate transition portion is connected between the first connecting portion and the second connecting portion, and the second connecting portion extends away from the main body. ### Claim 9 (depends on 8) The secondary battery according to claim 8, wherein the first connecting portion is formed in an annular shape, the intermediate transition portion is formed in a tubular shape, and the second connecting portion is formed in an annular shape. ### Claim 10 (depends on 8) The cap assembly secondary battery according to claim 8, wherein the cap plate is provided with a groove, and the second connecting portion is received in the groove, the groove comprises a first planar surface and a first arc surface, the second connecting portion comprises a second planar surface and a second arc surface, the first arc surface is engaged with the second arc surface while the first planar surface is connected to the second planar surface so as to prevent the connecting member from rotating relative to the cap plate. ### Claim 11 (depends on 1) The secondary battery according to claim 1, wherein the main body of the electrode terminal is does not extend into the electrode lead-out hole. ### Claim 12 (depends on 1) The secondary battery according to claim 1, wherein the recess is configured to not extend through the main body in a thickness direction, and the protrusion engages with the recess to apply a force towards the cap plate to the main body.