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CN-115810786-B - Roll, winding device, cell winding method, electrochemical device, and electronic apparatus

CN115810786BCN 115810786 BCN115810786 BCN 115810786BCN-115810786-B

Abstract

The application relates to a roller, a winding device, a cell winding method, an electrochemical device and an electronic device. The roller comprises a roller main body and an acting piece, wherein the acting piece is positioned on the outer wall of the roller main body and is provided with an acting substance, and the acting piece can contact with the positive electrode active material of the positive electrode plate before the positive electrode plate is wound on a winding shaft.

Inventors

  • SHI CHUNMEI
  • Cai Rule
  • YANG CHENGLONG
  • HU YONG
  • ZHANG HAIMING
  • TANG DAICHUN

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20211020

Claims (18)

  1. 1. A roll for a winding apparatus, comprising: a roller body capable of rotating axially around itself; An action member located on an outer wall of the roller body; The acting piece is provided with an acting substance, and the acting substance can be contacted with the positive electrode active material of the positive electrode plate before the positive electrode plate is wound on the winding shaft, so that the activity of the positive electrode active material is reduced.
  2. 2. A roll according to claim 1, wherein the reaction member comprises a first chamber containing the reaction substance, the chamber walls of the first chamber having capillary openings to retain the reaction substance within the first chamber.
  3. 3. A roll according to claim 2, wherein the first chamber has a communication portion for communicating with a pressure source, the active substance flowing out of the capillary holes to contact the positive electrode sheet when the pressure source applies pressure to the active substance.
  4. 4. The roll of claim 2, wherein the capillary openings are one or more of circular or polygonal in shape.
  5. 5. A roll according to claim 2, characterized in that the viscosity of the active substance is 0.5-8 mPa-s.
  6. 6. A roll according to claim 2, wherein the active substance comprises one or more of water, N-methylpyrrolidone.
  7. 7. A roll according to claim 2, wherein the inner and outer walls of the roll body define a second chamber containing the active substance, the second chamber being in communication with the first chamber for supplying the active substance thereto.
  8. 8. A roll according to claim 1, characterized in that the application member comprises an adhesive area, which is provided with a gummed paper, which gummed paper comprises a substrate and a backing adhesive bonded to the substrate, the application substance comprising the backing adhesive.
  9. 9. A roll according to any one of claims 1-8, characterized in that the roll body is circular or polygonal in shape.
  10. 10. The roll of claim 8 wherein the backing comprises any pressure sensitive adhesive having a 180 degree plane peel strength >0.01N/mm and the substrate is selected from the group consisting of polyethylene terephthalate, polypropylene, and fusible polytetrafluoroethylene.
  11. 11. A winding device, characterized by comprising: the winding shaft is used for winding the positive pole piece; a roller according to any one of claims 1-10, wherein said roller is located on the upstream side of said winding shaft; And the intermittent actuating device is connected with the roller piece, so that the acting piece of the roller piece can intermittently contact the acting substance with the positive electrode active material of the positive electrode plate before the positive electrode plate is wound on the winding shaft, and the activity of the positive electrode active material is reduced.
  12. 12. The winding device according to claim 11, comprising a plurality of press roll positions, wherein at least one of the plurality of press roll positions is provided with the roll member in correspondence.
  13. 13. A winding device, characterized by comprising: the winding shaft is used for winding the positive pole piece; a roller according to claim 8 or 10, wherein the roller is located on the upstream side of the winding shaft; the intermittent actuating device is connected with the roller piece, so that the acting piece of the roller piece can intermittently contact the acting substance with the positive electrode active material of the positive electrode plate before the positive electrode plate is wound on the winding shaft, and the activity of the positive electrode active material is reduced; The intermittent actuating device comprises a position adjusting mechanism, and the position of the roller piece can be intermittently adjusted until the back adhesive contacts with the positive pole piece so as to bond part of the material of the positive pole piece away from the positive pole piece.
  14. 14. A winding device, characterized by comprising: the winding shaft is used for winding the positive pole piece; a roller according to any one of claims 2-7, wherein said roller is located on the upstream side of said winding shaft; the intermittent actuating device is connected with the roller piece, so that the acting piece of the roller piece can intermittently contact the acting substance with the positive electrode active material of the positive electrode plate before the positive electrode plate is wound on the winding shaft, and the activity of the positive electrode active material is reduced; The intermittent actuation device includes a pressure source capable of intermittently applying pressure to the active substance so that the active substance intermittently flows out of the capillary holes to be in contact with the positive electrode sheet.
  15. 15. A method of winding a battery cell, characterized in that the active material is applied to the positive electrode active material of the positive electrode sheet to be wound by using the roll member according to any one of claims 1 to 10 to reduce the activity of the positive electrode active material.
  16. 16. The method of winding a battery cell according to claim 15, wherein the active material is in contact with the inner corner position of the positive electrode sheet when the positive electrode sheet being wound corresponds to the inner corner position of the positive electrode sheet, and is not in contact with the positive electrode sheet when the positive electrode sheet being wound corresponds to a position other than the inner corner position of the positive electrode sheet.
  17. 17. The method of winding a battery cell according to claim 16, wherein the active material is in contact with an inner corner position of an innermost positive electrode sheet of the battery cell when the positive electrode sheet to be wound is the inner corner position of the innermost positive electrode sheet, and is in non-contact with the positive electrode sheet when the positive electrode sheet to be wound is in a position other than the inner corner position of the innermost positive electrode sheet.
  18. 18. The cell winding method according to claim 16 or 17, wherein when the positive electrode sheet to be wound corresponds to the inner-ring corner position of the positive electrode sheet, the action time of the action substance with the inner-ring corner position is 1s to 2min.

Description

Roll, winding device, cell winding method, electrochemical device, and electronic apparatus Technical Field The application relates to a roll, a winding device, a cell winding method, an electrochemical device and an electronic device. Background The winding type structure is one of the common battery cell structures of the current secondary battery, and has the advantages of high production efficiency and low cost. However, the battery cell with the winding structure has the safety risk and even has the problems of short circuit failure and the like. Disclosure of Invention In view of the problems in the prior art, the present application aims to provide a roller, a winding device, a cell winding method, an electrochemical device and an electronic device, so as to solve the safety problem of the winding type cell and improve the reliability of the electrochemical device and the electronic device. In a first aspect, the application provides a roller comprising a roller body, an acting member located on an outer wall of the roller body, wherein the acting member has an acting substance capable of contacting a winding object before the winding object is wound on a winding shaft. In the technical scheme of the embodiment of the application, the property of a winding object is convenient to change, for example, a roller is suitable for a winding device of a winding type battery Cell, an acting element of the roller is adopted to contact an acting substance with a positive electrode active material of the positive electrode plate, the CB value (Cell Balance, the ratio of the active material capacity of a negative electrode to the active material capacity of the positive electrode) of the inner ring corner position of the battery Cell is improved, the lithium precipitation problem can be effectively avoided, the safety problem of the winding type battery Cell is solved, the reliability of an electrochemical device and electronic equipment is improved, meanwhile, the structure of the roller is adopted, the influence on the winding production process is small, and the advantages of high production efficiency and low cost of the winding type battery Cell are reserved. In some embodiments, the action member comprises a first chamber containing the action substance, the chamber wall of the first chamber having capillary holes to retain the action substance within the first chamber. The capillary structure can control the contact time of the active substance with the wound object by a simple structure. In some embodiments, the first chamber has a communication for communicating with a pressure source that, when applying pressure to the active substance, flows out of the capillary holes to contact the windings. The structure that the pressure source is communicated with the first cavity is adopted, the structure is simple, the influence on the property of the acting substance is small, and the reliability of the acting substance on the active material is improved. In some embodiments, the capillary holes are one or more of round or polygonal in shape, and through flexible arrangement of the capillary holes, sufficient contact of the active substances with various areas and inner ring corner positions of the shapes can be ensured. In some embodiments, the active substance has a viscosity of 0.5-8mPa/s, and the active substance in this viscosity range is easily accommodated in the first chamber. In some embodiments, the active substance comprises one or more of water, N-methylpyrrolidone, which is a common substance in cell production, readily available. In some embodiments, the inner wall and the outer wall of the roller body define a second chamber, the second chamber contains the active substance, the second chamber is communicated with the first chamber so as to supply the active substance to the first chamber, thus the active substance can be stored by utilizing the self structure of the roller body, the active substance is conveniently conveyed to the first chamber of the acting piece, and the integration level of the winding device comprising the roller piece is improved, so that the winding device is compact in structure. In some embodiments, the active member includes an adhesive region provided with an adhesive sheet including a substrate and a backing adhesive bonded to the substrate, and the active substance includes the backing adhesive. The gummed paper structure is adopted, so that the roller is easy to arrange on the roller main body, and the roller is simple in structure. In some embodiments, the roller body is circular or polygonal in shape, and by flexible setting of the shape of the roller body, the shape of the bonding area of the acting element can be ensured to be matched with the shape of the winding type battery cell, and the gummed paper is fully contacted with the inner ring corner positions of various areas and shapes. In some embodiments, the back adhesive comprises any pressure-sensitive adhe