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CA-3224567-C - DEVICE AND METHOD FOR MANUFACTURING AN ELECTRODE

CA3224567CCA 3224567 CCA3224567 CCA 3224567CCA-3224567-C

Abstract

The invention relates to a method for manufacturing an electrode (4) with a substrate (30) and with a first dry film (22), wherein to form a first dry film (22), solvent-free dry film material is brought into a first nip (18) formed between a first roller (6) and a second roller (8), wherein the first dry film (22) formed in the first nip (18) is conveyed roller-borne into a second nip (24) formed between the second roller (8) and a third roller (10) and compressed there, and wherein, for laminating, the compressed first dry film (22) and the substrate (30) are conveyed into a third nip (26) formed between the third roller (10) and a fourth roller (12), wherein the first dry film (22) is conveyed roller-borne into the third nip (26). Moreover, the invention relates to a corresponding device (2) for manufacturing the electrode (4).

Inventors

  • Ludger Bußwinkel
  • Sebastian Reuber
  • Roland Schmidt-Lobach
  • Sven Schopf

Assignees

  • VOLKSWAGEN AG

Dates

Publication Date
20260505
Application Date
20231222
Priority Date
20230103

Claims (18)

  1. 27 What is claimed is: 1. A method for manufacturing an electrode with a foil-like substrate and with a first dry film, wherein to form the first dry film, solvent-free dry film material is conveyed into a first nip formed between a first roller and a second roller, wherein the first dry film formed in the first nip is conveyed roller-borne into a second nip formed between the second roller and a third roller and compressed there, wherein for lamination, the compressed first dry film and the substrate are conveyed into a third nip formed between the third roller and a fourth roller, wherein the first dry film is conveyed roller-borne into the third nip, and wherein line load for dry film formation in the first nip is between 200 N/mm and 2000 N/mm, line load for the compression in the second nip is between 500 N/mm and 4000 N/mm, and line load for the lamination in the third nip is between 200 N/mm and 2000 N/mm.
  2. 2. The method according to claim 1, wherein to form a second dry film, solvent-free dry film material is brought into a fourth nip formed between a fifth roller and a sixth roller, wherein the second dry film formed in the fourth nip is conveyed roller-borne into a fifth nip formed between the sixth roller and a seventh roller and compressed there, wherein, for joint lamination, the compressed second dry film and the substrate laminated with the first dry film are conveyed into a sixth nip formed between the seventh roller and an eighth roller, and wherein the second dry film is conveyed roller-borne into the 28 sixth nip.
  3. 3. The method according to claim 1, wherein to form a second dry film, solvent-free dry film material is conveyed into a fourth nip formed between a fifth roller and a sixth roller, wherein the second dry film formed in the fourth nip is conveyed roller-borne into a fifth nip formed between the sixth roller and the fourth roller and compressed there, wherein, for joint lamination, the compressed second dry film, the substrate and the first dry film are conveyed into the third nip, and wherein the second dry film is conveyed roller-borne into the third nip.
  4. 4. The method according to any one of claims 1 to 3, wherein the first dry film is compressed in the second nip to a density between 1.0 g/cm3 and 4 g/cm3.
  5. 5. The method according to any one of claims 1 to 3, wherein the first dry film is compressed in the second nip to a density between 1.4 g/cm3 and 3.7 g/cm3.
  6. 6. The method according to claim 2 or 3, wherein the second dry film is compressed in the fifth nip to a density between 1.0g/cm3 and 4g/cm3.
  7. 7. The method according to claim 2 or 3, wherein the second dry film is compressed in the fifth nip to a density between 1.4 g/cm3 and 3.7 g/cm3.
  8. 8. The method according to claim 6 or 7, wherein the first dry film is compressed in the second nip to a density between 1.0 g/cm3 29 and 4 g/cm3.
  9. 9. The method according to claim 6 or 7, wherein the first dry film is compressed in the second nip to a density between 1.4 g/cm3 and 3.7 g/cm3.
  10. 10. The method according to one of claims 1 to 9, wherein the first dry film is compressed in the second nip to a thickness between 10 μm and 200 μm.
  11. 11. The method according to one of claims 1 to 9, wherein the first dry film is compressed in the second nip to a thickness between 40 μm and 120 μm.
  12. 12. The method according to any one of claims 2, 3, and 6 to 9, wherein the second dry film is compressed in the fifth nip to a thickness between 10μm and 200μm.
  13. 13. The method according to any one of claims 2, 3, and 6 to 9, wherein the second dry film is compressed in the fifth nip to a thickness between 40μm and 120μm.
  14. 14. The method according to one of claims 1 to 13, wherein the circumferential speed of the second roller is greater than the circumferential speed of the first roller, and/or wherein the circumferential speed of the third roller is greater than the circumferential speed of the second roller.
  15. 15. The method according to one of claims 1 to 14, wherein the temperature of the second roller is adjusted to be greater than the temperature of the first roller, and/or wherein the temperature of the third roller is greater than the temperature of the second roller.
  16. 16. The method according to one of claims 1 to 15, wherein the surface of the second roller has a greater roughness than the surface of the first roller, and/or wherein the surface of the third roller has a greater roughness than the surface of the second roller.
  17. 17. A device for manufacturing an electrode with a substrate and with a first dry film comprising: a first roller and a second roller, wherein a first nip is formed between the first roller and the second roller, a conveying apparatus for conveying solvent-free dry film material into the first nip, a third roller, wherein a second nip is formed between the second roller and the third roller for compressing a first dry film formed in the first nip, a fourth roller, wherein a third nip is formed between the third roller and the fourth roller, and a feed apparatus for feeding the substrate into the third nip, wherein line load of the first nip, the second nip, and/or the third nip is individually adjustable, and wherein line load for dry film formation in the first nip is between 200 N/mm and 2000 N/mm, line load for the compression in the second nip is between 500 N/mm and 4000 N/mm, and line load in the third nip for lamination of the compressed first dry film and the substrate is between 200 N/mm and 2000 N/mm.
  18. 18. The device according to claim 17, wherein: gap width of the first nip, the second nip, and/or the third nip is individually adjustable, and/or 31 the gap width is regulated in the first nip, and/or the second nip.

Description

Description Device and method for manufacturing an electrode The invention relates to a device and a method for manufacturing an electrode which comprises a substrate and a dry film layer with active material. To manufacture an electrode with a substrate and with a dry film as is known, for example, from WO 2018/210723 Al, first a dry film material is conveyed using a powder conveyor between two rollers of a roller device. By using these rollers, pressure and/or shear forces are introduced into the dry film material so that the dry film forms. The dry film is conveyed on one of the rollers into another gap. In so doing, a substrate is additionally fed through this additional gap so that the dry film is laminated to the substrate. In such a manufacturing method, the dry film has a comparatively low density. This is disadvantageous with regard to energy and/or power density for direct use in a battery of a motor vehicle so that the dry film is typically recompressed. For this purpose, the dry film is recompressed, for example, while laminating the substrate with the dry film. However, the risk exists of wrinkling in an arrester area of the substrate and/or the risk of a crack in the substrate, in particular due to inhomogeneities. The object of the invention is to present a particularly suitable method and/or a particularly suitable device for manufacturing an electrode with a substrate and with a dry film. In particular, the manufactured electrode should have a comparatively dense dry film, 1 Date Re9ue/Date Received 2023-12-22 and/or recompression during lamination should be avoided. With regard to the method, the object is solved according to the invention by the features of claim 1. With respect to the device, the object is solved according to the invention by the features of claim 9. Advantageous embodiments and developments are the subject matter of the dependent claims. The statements associated with the device also apply analogously to the method and vice versa. The invention relates to a method for manufacturing an electrode, in particular for a lithium-ion battery. In this case, the electrode comprises a substrate, in particular a foil-like substrate such as a metal foil, and a first dry film, which is arranged on a first side of the substrate, preferably joined to the substrate, in particular laminated onto the substrate. The substrate expediently forms a current collector of the electrode. The dry film expediently forms a layer with active material which is provided in particular for an anode or for a cathode of a lithium-ion battery. According to the method, in a first step to form a first dry film, solvent-free dry film material is brought, in particular conveyed, into a first nip, which first nip is formed between a first roller and a second roller. The dry film material conveyed into the first nip is processed using the first and the second roller into the first dry film. For this purpose, a pressing and/or shearing force is generated on the dry film material using the first and second roller so that the particles of the dry film material bond together. The dry film material is expediently a granular material also described as a granulate, for example a powder or a powder mixture. 2 Date Re9ue/Date Received 2023-12-22 The dry film material has a (dry) active material, a (dry) binder, and/ or a ( dry) conductive agent. In other words, the dry film material comprises a mixture consisting of undissolved active material particles, undissolved binder particles, and/or undissolved conductive agent particles. In a second step, the first dry film formed in the first nip is conveyed roller-borne into a second nip, which is formed between the second roller and a third roller. In other words, the first dry film is conveyed using the second roller from the first nip into the second nip. In so doing, the first dry film is not freestanding, but is arranged on the second roller for conveyance from the first nip to the second nip, and is in particular borne, that is, entrained, thereby. By using the second and the third roller, the first dry film is compressed in the second nip. The first dry film is expediently compressed to a specified target density or a specified target thickness. The target density, or respectively the target thickness is in particular the density, or respectively thickness which the dry film should have after the manufacture of the electrode, that is, also in its use in a battery cell, in particular a Li-ion battery cell. The target density, or respectively the target thickness is hence preferably selected such that additional compression of the dry film is unnecessary and is expediently also not carried out. Accordingly, recompression of the first dry film during lamination onto the substrate (see step three) is unnecessary. Alternatively, a comparatively low line load is used for this purpose. As a result, the risk of damage to the first dry film and/or the substrate during recompress