# US 2026/0100403 A1 · Mandrel for winding electrode of secondary battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2026/0100403 A1 - Document ID: US20260100403A1 - Status: Published application - Kind: A1 - Application number: 19/348,919 - Filed: 2025-10-03 - Published: 2026-04-09 - Earliest claimed: 2024-10-08 - Assignees: Samsung SDI Co., Ltd. - Applicants: Samsung SDI Co., Ltd. - Inventors: Ju Hyung Lee - Web page: https://patentgrep.com/patent/US20260100403A1 ## CPC - H01M 10/0409: {for cells with wound electrodes} - H01M 10/0431: {Cells with wound or folded electrodes (H01M10/045 takes precedence)} - Y02E 60/10: Energy storage using batteries - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - 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 - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract The present disclosure relates to a mandrel for winding an electrode of a secondary battery, and provides a mandrel for winding an electrode of a secondary battery including a first mandrel member comprising a plurality of exterior faces including longitudinal side surfaces and a first surface, wherein a first hollow portion is provided between the longitudinal side surfaces, and a second mandrel member spaced apart from the first mandrel member and comprising a plurality of exterior faces including second longitudinal side surfaces and a second surface, wherein a second hollow portion is provided between the second longitudinal side surfaces. ## Claims ### Claim 1 A mandrel for winding an electrode of a secondary battery, comprising: a first mandrel member comprising a plurality of exterior faces including longitudinal side surfaces and a first surface, wherein a first hollow portion is provided between the longitudinal side surfaces; and a second mandrel member spaced apart from the first mandrel member, the second mandrel comprising a plurality of exterior faces including second longitudinal side surfaces and a second surface facing the first surface, wherein a second hollow portion is provided between the second longitudinal side surfaces. ### Claim 2 (depends on 1) The mandrel of claim 1, wherein the first mandrel member includes: a first flat surface intersecting the first surface and including a first through hole portion; and a second flat surface intersecting the first surface, spaced apart from and facing the first flat surface, and including a second through hole portion. ### Claim 3 (depends on 2) The mandrel of claim 2, wherein the first mandrel member includes a first tip portion protruding from the first flat surface and accommodated in the first hollow portion. ### Claim 4 (depends on 3) The mandrel of claim 3, wherein the first tip portion is not in contact with the second flat surface and has a width that becomes smaller toward an end portion. ### Claim 5 (depends on 3) The mandrel of claim 3, wherein the first mandrel member further includes a second tip portion protruding from the second flat surface and accommodated in the first hollow portion. ### Claim 6 (depends on 5) The mandrel of claim 5, wherein the second tip portion is not in contact with the first flat surface and has a width that becomes smaller toward an end portion. ### Claim 7 (depends on 5) The mandrel of claim 5, wherein the first tip portion comprises a plurality of first tip portions, the second tip portion comprises a plurality of second tip portions, and the plurality of first and second tip portions are disposed to be spaced apart from each other along a longitudinal direction of the first mandrel member. ### Claim 8 (depends on 7) The mandrel of claim 7, wherein the plurality of first tip portions and second tip portions are disposed in an alternating manner. ### Claim 9 (depends on 2) The mandrel of claim 2, wherein the first mandrel member includes: a first inclined surface extending in an inclined manner from the first flat surface; and a second inclined surface extending in an inclined manner from the second flat surface and connected to the first inclined surface. ### Claim 10 (depends on 9) The mandrel of claim 9, wherein: an interior angle between the first flat surface and the first inclined surface forms an obtuse angle; and an interior angle between the second flat surface and the second inclined surface forms an obtuse angle. ### Claim 11 (depends on 1) The mandrel of claim 1, wherein the second mandrel member includes: a third flat surface intersecting the second surface and including a third through hole portion; and a fourth flat surface intersecting the second surface, spaced apart from and facing the third flat surface, and including a fourth through hole portion. ### Claim 12 (depends on 11) The mandrel of claim 11, wherein the second mandrel member includes a third tip portion protruding from the third flat surface and accommodated in the second hollow portion. ### Claim 13 (depends on 12) The mandrel of claim 12, wherein the third tip portion is not in contact with the fourth flat surface and has a width that becomes smaller toward an end portion. ### Claim 14 (depends on 12) The mandrel of claim 12, wherein the second mandrel member further includes a fourth tip portion protruding from the fourth flat surface and accommodated in the second hollow portion. ### Claim 15 (depends on 14) The mandrel of claim 14, wherein the fourth tip portion is not in contact with the third flat surface and has a width that becomes smaller toward an end portion. ### Claim 16 (depends on 14) The mandrel of claim 14, wherein the third tip portion comprises a plurality of third tip portions, the fourth tip portion comprises a plurality of fourth tip portions, and the plurality of third and fourth tip portions are disposed to be spaced apart from each other along a longitudinal direction of the second mandrel member. ### Claim 17 (depends on 16) The mandrel of claim 16, wherein the plurality of third tip portions and fourth tip portions are disposed in an alternating manner. ### Claim 18 (depends on 11) The mandrel of claim 11, wherein the second mandrel member includes: a third inclined surface extending in an inclined manner from the third flat surface; and a fourth inclined surface extending in an inclined manner from the fourth flat surface and connected to the third inclined surface. ### Claim 19 (depends on 18) The mandrel of claim 18, wherein: an interior angle between the third flat surface and the third inclined surface forms an obtuse angle; and an interior angle between the fourth flat surface and the fourth inclined surface forms an obtuse angle.