# US 2018/0026309 A1 · Separator core and separator roll > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026309 A1 - Document ID: US20180026309A1 - Status: Published application - Kind: A1 - Application number: 15/654,946 - Filed: 2017-07-20 - Published: 2018-01-25 - Earliest claimed: 2016-07-21 - Assignees: Sumitomo Chemical Company, Limited - Applicants: Sumitomo Chemical Company, Limited - Inventors: Daizaburo YASHIKI; Daijiro HOSHIDA - Web page: https://patentgrep.com/patent/US20180026309A1 ## CPC - H01M 10/0587: of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators - B65H 75/10: without flanges, e.g. cop tubes - H01M 4/13: Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof - H01M 10/049: {Processes for forming or storing electrodes in the battery container} - H01M 10/052: Li-accumulators - H01M 10/0567: characterised by the additives - H01M 50/403: Manufacturing processes of separators, membranes or diaphragms - H01M 50/461: {with adhesive layers between electrodes and separators} - B65H 2401/11: Polymer compositions - B65H 2701/5122: Plastics - B65H 2701/534: Stackable or interlockable reels or parts of reels - B65H 2701/535: Dimensional aspect, e.g. non-cylindrical cores - H01M 50/406: Moulding; Embossing; Cutting - 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 - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES - 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 A core (u1, u2) around which a nonaqueous electrolyte secondary battery separator is to be wound. A side surface of the core (u1, u2) has a depression (20). This makes it possible, in a case where cores (separator cores) are stored by being stacked while still wet after cleaning, to prevent damage to a core caused by a problem where cores stick together and an core lower in a stack falls when a core higher in the stack is removed. ## Claims ### Claim 1 A separator core around which a nonaqueous electrolyte secondary battery separator is to be wound, wherein: a side surface of the separator core has a depression. ### Claim 2 (depends on 1) The separator core according to claim 1, wherein: the depression includes an imprinted portion. ### Claim 3 (depends on 1) The separator core according to claim 1, wherein: each of an outer ring, a rib, and an inner ring constituting the separator core is identical in width, as measured in a direction of a stacking axis which passes through a center of the side surface of the separator core; and the depression is provided to at least one of (i) a side surface of the outer ring, (ii) a side surface of the rib, and (iii) a side surface of the inner ring. ### Claim 4 (depends on 3) The separator core according to claim 3, wherein: the depression includes an imprinted portion. ### Claim 5 (depends on 3) The separator core according to claim 3, wherein: the depression is one of a plurality of depressions which are provided to at least one of two side surfaces of the separator core, the plurality of depressions being provided such that, when viewed from above, in a case where any one of the plurality of depressions is rotated around the stacking axis, the one of the plurality of depressions which is rotated overlaps with each other one of the plurality of depressions. ### Claim 6 (depends on 3) The separator core according to claim 3, wherein: the depression is one of a plurality of depressions which are provided to at least one of two side surfaces of the separator core, the plurality of depressions being provided such that, when viewed from above, in a case where any one of the plurality of depressions is rotated around the stacking axis, the one of the plurality of depressions which is rotated does not overlap with each other one of the plurality of depressions. ### Claim 7 (depends on 1) The separator core according to claim 1, wherein: the depression is rotationally symmetrical, at all angles of rotation, with respect to a stacking axis which passes through a center of the side surface of the separator core. ### Claim 8 (depends on 1) The separator core according to claim 1, wherein: the separator core is constituted by an outer ring, a rib, and an inner ring; and the depression is constituted by a portion of the separator core in which portion one or two of (i) the outer ring, (ii) the rib, and (iii) the inner ring is/are smaller in width, as measured in a direction of a stacking axis which passes through a center of the side surface of the separator core, than each remaining one of (i) the outer ring, (ii) the rib, and (iii) the inner ring. ### Claim 9 (depends on 8) The separator core according to claim 8, wherein: the depression is constituted by a portion of the separator core in which portion the inner ring is smaller in width, as measured in the direction of the stacking axis, than the outer ring. ### Claim 10 (depends on 8) The separator core according to claim 8, wherein: the depression is constituted by a portion of the separator core in which portion the outer ring is smaller in width, as measured in the direction of the stacking axis, than the inner ring. ### Claim 11 (depends on 8) The separator core according to claim 8, wherein: the rib includes a plurality of ribs; and the depression is constituted by a portion of the separator core in which portion each of the outer ring and the inner ring is smaller in width, as measured in the direction of the stacking axis, than each of the plurality of ribs. ### Claim 12 (depends on 8) The separator core according to claim 8, wherein: the rib includes a plurality of ribs; and the depression is constituted by a portion of the separator core in which portion each of the plurality of ribs is smaller in width, as measured in the direction of the stacking axis, than each of the outer ring and the inner ring. ### Claim 13 (depends on 1) The separator core according to claim 1, wherein: the depression has a depth of not less than 0.1 mm. ### Claim 14 (depends on 1) The separator core according to claim 1, wherein: the depression occupies not less than 3% and not more than 25% of a total area of the side surface having the depression. ### Claim 15 (depends on 1) A separator roll comprising: a separator core as recited in claim 1; and a nonaqueous electrolyte secondary battery separator wound around the separator core.