Process for producing a dry film, system for producing a dry film, dry film, and battery containing the dry film

Abstract

The invention relates to a method for preparing a dry film, a system for preparing the dry film, the dry film and a battery comprising the dry film. The method and the system are characterized in that at least two processing devices are used, which are respectively arranged relative to the outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, where the at least two processing devices are adapted to remove a region of the dry film mounted on the carrier roller and on the outer section of the carrier roller. The method and system can provide segmented strip-shaped dry films with high edge accuracy in a fast and energy-saving manner.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202480009638.3 (22) Application Date 2024.01.25 (30) Priority Data 102023101943.0 2023.01.26 DE (85) PCT International Application Entering National Phase Date 2025.07.28 (86) PCT International Application Application Data PCT / EP2024 / 051814 2024.01.25 (87) PCT International Application Publication Data WO2024 / 156822 DE 2024.08.02 (71) Applicant: Fraunhofer Association for the Promotion of Applied Research Address: Munich, Germany (72) Inventors: Julius Rochholg Altschs, Benjamin Schum, Christian Gilles Süle, Sebastian Chek (74) Patent Agency: Beijing Baishansong Intellectual Property Agency (General Partnership) 11413 Patent Attorneys: She Yumei, Xie Pan (51) Int.Cl. B05D 1 / 40 (2006.01) H01M 4 / 04 (2006.01) H01M 10 / 04 (2006.01) (54) Invention Title: Method and System for Preparing Dry Film, Dry Film and Battery Containing Dry Film (57) Abstract: This invention relates to a method for preparing a dry film, a system for preparing a dry film, a dry film and a battery containing the dry film. The method and system are characterized by using at least two processing devices arranged relative to the outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller. These at least two processing devices are adapted to remove the area of ​​the dry film mounted on the carrier roller and on its outer section. The method and system can provide segmented strip dry film with high edge accuracy in a fast and energy-efficient manner.Claims 8 pages, Description 22 pages, Drawings 8 pages, CN 121152689 A 2025.12.16 CN 1 21 15 26 89 A 1. A method for preparing a dry film, comprising feeding a dry powder mixture and / or a dry mixture into a first calendering roll gap formed by a carrier roller and a first pair of pressure rollers, wherein the carrier roller rotates about a carrier roller rotation axis at a first circumferential speed in a first rotation direction, and the pressure rollers rotate about a pressure roller rotation axis at a second circumferential speed lower than the first circumferential speed in a second rotation direction, wherein the second rotation direction is opposite to the first rotation direction, wherein the dry powder mixture and / or the dry mixture passes through the first calendering roll gap in a conveying direction, wherein a dry film is formed that is supported on the carrier roller in at least some areas. The invention is characterized by using at least one first processing device, which is arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller; and using at least one second processing device, which is arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, wherein the carrier roller has an inner section located between the first outer section and the second outer section in a direction parallel to the axis of rotation of the carrier roller, wherein the first processing device and the second processing device are each adapted to remove the region of the dry film supported on the carrier roller and located at the outer section of the carrier roller. 2. The method according to the preceding claim, characterized in that the dry film is laminated onto a substrate during the method, wherein the substrate preferably has at least some regions an undercoat, a three-dimensional structure, a texture, and / or a porous layer for enhancing the adhesion of the dry film, wherein, particularly preferably, i) the undercoat comprises or is composed of a polymer and a conductive material, the thickness of the undercoat is less than 10 μm, preferably less than 2 μm, and / or the undercoat is arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller; and / or ii) the substrate comprises or is composed of a woven fabric, a nonwoven fabric, and / or a stretched mesh as a three-dimensional structure; and / or iii) the texture is prepared by etching, sandblasting, and / or laser processing, wherein the texture is particularly present on the surface of the substrate facing the dry film; and / or iv) the porous layer comprises or is composed of an electrode layer and / or a granular layer.3. The method according to any one of the preceding claims, characterized in that the inner section of the carrier roller has a surface quality to which dry film adheres in at least some regions, wherein, i) the first outer section and / or the second outer section of the carrier roller has a surface quality to which dry film does not adhere, wherein the surface quality is preferably configured as a smooth surface of the carrier roller, wherein the center roughness value Ra of the smooth surface is preferably less than or equal to 50% of the center roughness value of the carrier roller in the inner section, wherein the center roughness value Ra of the smooth surface is particularly preferably 0.005 μm to 1 μm; and / or ii) the first outer section and / or the second outer section of the counterpressure roller has a surface quality to which dry film does not adhere, the first outer section of the counterpressure roller is arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, and the second outer section of the counterpressure roller is arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, wherein the surface quality of the first outer section and / or the second outer section of the counterpressure roller is preferably: a) A concave surface formed as the pressure roller, wherein the radius of the concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, especially less than or equal to 90%, of the radius of the pressure roller in the first region of the inner section of the pressure roller; and / or b) A coating formed as the first outer section and / or the second outer section of the pressure roller, preferably formed as a coating comprising DLC ​​and / or PTFE or composed of DLC and / or PTFE on the first outer section and / or the second outer section of the pressure roller. (Claims 1 / 8 page 2 CN 121152689 A) The coating consists of a composition that results in at least 1 wt.% less dry film adhesion on the pressure roller than the inner section of the pressure roller, particularly at least 10 wt.% less, and preferably no adhesion on the pressure roller. The inner section of the pressure roller optionally has a coating and / or texture to which the dry film adheres. The coating particularly preferably comprises or consists of materials selected from or composed of materials selected from: PTFE, DLC, tungsten carbide, hard chrome, and combinations thereof. The carrier roller optionally has at least one second region of the inner section, the at least one second region being configured similarly to the first outer section and / or the second outer section of the carrier roller.4. The method according to any one of the preceding claims, characterized in that the first processing apparatus and the second processing apparatus each: i) include a cutting unit for separating a region of the dry film supported on the carrier roller at a corresponding outer segment of the carrier roller from a region of the dry film supported on the carrier roller at a corresponding inner segment of the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof; and / or ii) include a removal unit for removing a region of the dry film supported on the carrier roller and located at a corresponding outer segment of the carrier roller, wherein the removal unit is preferably selected from an air nozzle, a scraper, a brush, a suction device, or a combination thereof; and / or iii) have an additional removal unit for removing a region of the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction. 5. The method according to any one of the preceding claims, characterized in that the inner section of the carrier roller is divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, wherein n is an integer, and intermediate regions are respectively arranged between two adjacent inner section regions, the boundaries of the intermediate regions being defined by two opposing boundary lines of the 2n boundary lines in the direction of the rotation axis of the carrier roller, wherein i) the at least two inner section regions have a surface quality to which dry film adheres, and the intermediate regions preferably each have a surface quality to which dry film does not adhere; and / or ii) in a direction perpendicular to the rotation axis of the carrier roller, additional processing equipment is used, respectively opposite to each intermediate region of the inner section, the additional processing equipment being adapted to remove, at least by cutting, a region of the dry film supported on the carrier roller and located in the intermediate region of the carrier roller, wherein each additional processing equipment is particularly preferably: The device includes a cutting unit for separating a region of the dry film supported on the carrier roller at a corresponding intermediate region of the carrier roller from a region of the dry film supported on the carrier roller at an inner section of the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof; and / or includes a removal unit for removing a region of the dry film supported on the carrier roller and located at a corresponding intermediate region of the carrier roller, wherein the removal unit is preferably selected from an air nozzle, a scraper, a brush, a suction device, or a combination thereof.6. The method according to any one of claims 4 or 5, characterized in that the removal unit is used, and optionally the additional removal unit is also used, to feed the removed area of ​​the dry film into a first calendering roll gap, optionally first i) feeding the removed area of ​​the dry film into a dry mixture, the dry mixture being processed into a dry powder mixture, the dry powder mixture being then fed into the first calendering roll gap, wherein processing into a dry powder mixture preferably includes processing selected from extruder processing, jet mill, pin mill, impact mill, mortar mill, roller mill, and combinations thereof; or ii) feeding the removed area of ​​the dry film into a dry mixture and / or a dry mixture, the dry powder mixture and / or the dry mixture being then fed into the first calendering roll gap, wherein the proportion of the removed area of ​​the fed dry film relative to the total proportion of the dry powder mixture and / or the dry mixture is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, and more particularly preferably at least 10 wt.%. 7. The method according to any one of the preceding claims, characterized in that the first calendering roll gap i) has a length of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm, and optionally at most 3000 mm; and / or ii) has a mask and / or funnel arranged above the calendering roll gap, wherein the mask preferably reduces the application of a certain amount of dry powder mixture and / or dry mixture to at least two opposing outer sections of the carrier roll, and optionally also to at least one intermediate region of the inner section of the carrier roll. 8. The method according to any one of the preceding claims, characterized in that the carrier roll and / or the counter-pressure roll a) has a diameter of less than or equal to 100 cm, optionally from 10 cm to 100 cm, particularly preferably less than or equal to 50 cm, optionally from 10 cm to 50 cm, and particularly less than 30 cm; and / or b) has a width greater than 30 cm, preferably greater than 60 cm, particularly preferably greater than 100 cm, and especially at most 300 cm, in a direction perpendicular to the roll axis of the carrier roll and / or the counter-pressure roll.9. The method according to any one of the preceding claims, characterized in that laminating a dry film on a substrate comprises the following steps: i) conveying the dry film on the carrier roller into a second calendering roll gap formed by the carrier roller and the second pair of pressure rollers, wherein the second pair of pressure rollers rotates about the rotation axis of the second pair of pressure rollers in a third rotation direction at a second circumferential speed greater than or equal to a first circumferential speed of the carrier roller, wherein the third rotation direction is opposite to the first rotation direction; ii) optionally, conveying the dry film together with the substrate through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, and especially at least a sixth calendering roll gap; iii) optionally, due to the increase in circumferential speed, conveying a substrate-free dry film through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, and especially at least a sixth calendering roll gap by transfer; wherein a substrate with a laminated dry film is produced. 10. A system for preparing a dry film, comprising: a) an apparatus configured to prepare a dry film from a dry powder mixture and / or a dry mixture, wherein the apparatus includes a carrier roller and a first pair of pressure rollers, wherein the carrier roller and the pressure rollers form a first calendering roll gap to supply the dry powder mixture and / or the dry mixture, wherein the carrier roller is adapted to rotate about a carrier roller rotation axis, and the pressure rollers are adapted to rotate about a pressure roller rotation axis; b) a control unit configured at least to rotate the carrier roller about its carrier roller rotation axis at a first circumferential speed in a first rotational direction, and to rotate the pressure roller about its pressure roller rotation axis at a second circumferential speed lower than the first circumferential speed in a second rotational direction, wherein the second rotational direction is opposite to the first rotational direction, wherein the control unit is particularly configured to set the roll gap width and / or contact pressure in the calendering roll gap between the carrier roller and the first pair of pressure rollers; The system is characterized in that it has at least one first processing device and at least one second processing device, the at least one first processing device being arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, and the at least one second processing device being arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, wherein the carrier roller has an inner section located between the first outer section and the second outer section in a direction parallel to the rotation axis of the carrier roller, and wherein the first processing device and the second processing device are each adapted to remove at least by cutting the area of ​​the dry film supported on the carrier roller and located at the outer section of the carrier roller.11. The system of claim 10, characterized in that the system comprises a substrate and is configured to laminate the dry film onto the substrate, wherein the substrate preferably has at least some regions an undercoat, a three-dimensional structure, a texture, and / or a porous layer for enhancing the adhesion of the dry film, wherein particularly preferred i) the undercoat comprises or is composed of a polymer and a conductive material, the thickness of the undercoat is less than 10 μm, preferably less than 2 μm, and / or the undercoat is arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller; and / or ii) the substrate comprises or is composed of a woven fabric, a nonwoven fabric, and / or a stretched mesh as a three-dimensional structure; and / or iii) the texture is prepared by etching, sandblasting, and / or laser processing; and / or iv) the porous layer comprises or is composed of an electrode layer and / or a granular layer.12. The system according to any one of claims 10 or 11, characterized in that the inner section of the carrier roller has a first surface quality to which dry film adheres in at least some regions, wherein, i) the first outer section and / or the second outer section of the carrier roller has a second surface quality to which dry film does not adhere, wherein the surface quality is preferably designed as a smooth surface of the carrier roller, wherein the center roughness value Ra of the smooth surface is preferably less than or equal to 50% of the center roughness value of the carrier roller in the inner section, wherein the center roughness value Ra of the smooth surface is particularly preferably 0.001 μm to 1 μm; and / or iii) the first outer section and / or the second outer section of the counterpressure roller has a surface quality to which dry film does not adhere, the first outer section of the counterpressure roller being arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, and the second outer section of the counterpressure roller being arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, wherein the surface quality of the first outer section and / or the second outer section of the counterpressure roller is preferably: a) A concave surface formed as the pressure roller, wherein the radius of the concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, especially less than or equal to 90%, of the radius of the pressure roller in the first region of the inner section of the pressure roller; and / or b) a coating formed as the first outer section and / or the second outer section of the pressure roller, preferably a coating comprising DLC ​​and / or PTFE or composed of DLC and / or PTFE, such that the dry film adhesion on the pressure roller is at least 1 wt.%, particularly at least 10 wt.%, less than the inner section of the pressure roller, and preferably has no adhesion on the pressure roller, wherein the inner section of the pressure roller optionally has a coating and / or texture to which the dry film adheres, wherein the coating particularly preferably comprises or is composed of materials selected from or composed of materials selected from: PTFE, DLC, tungsten carbide, hard chrome, and combinations thereof. The carrier roller may optionally have at least one second region of the inner section, the at least one second region being configured to resemble the first outer section and / or the second outer section of the carrier roller.13. The system according to any one of claims 10 to 12, characterized in that the first processing device and the second processing device each i) include a cutting unit configured to separate the region of the dry film at a corresponding outer segment of the carrier roller supported on the carrier roller from the region of the dry film at a corresponding inner segment of the carrier roller supported on the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, and combinations thereof; and / or ii) include a removal unit configured to remove the region of the dry film supported on the carrier roller and located at a corresponding outer segment of the carrier roller, wherein the removal unit is preferably selected from an air nozzle, a scraper, a brush, a suction device, and combinations thereof; and / or iii) have an additional removal unit configured to remove the region of the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction. 14. The system according to any one of claims 10 to 13, characterized in that the inner section of the carrier roller is divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, wherein n is an integer, and intermediate regions are respectively arranged between two adjacent inner section regions, the boundaries of the intermediate regions being defined by two opposing boundary lines of the 2n boundary lines in the direction of the rotation axis of the carrier roller, wherein i) the at least two inner section regions have a surface quality to which dry film adheres, and the intermediate regions preferably each have a surface quality to which dry film does not adhere; and / or ii) the system has, in a direction perpendicular to the rotation axis of the carrier roller, additional processing devices opposite to each intermediate region of the inner section, the additional processing devices being adapted to remove, at least by cutting, the region of the dry film supported on the carrier roller and located in the intermediate region of the carrier roller, wherein each additional processing device is particularly preferably: The device includes a cutting unit configured to separate a region of the dry film supported on the carrier roller at a corresponding intermediate region of the carrier roller from a region of the dry film supported on the carrier roller at an inner section of the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof; and / or includes a removal unit configured to remove a region of the dry film supported on the carrier roller and located at a corresponding intermediate region of the carrier roller, wherein the removal unit is preferably selected from an air nozzle, a scraper, a brush, a suction device, or a combination thereof.15. The system according to any one of claims 13 or 14, characterized in that the removal unit is configured to, optionally, also be configured to, feed the removed area of ​​the dry film into a first calendering roll gap, optionally first feed the removed area of ​​the dry film into a dry mixture being processed into a dry powder mixture, wherein the processing equipment of the system is configured to process the dry mixture into a dry powder mixture and feed the dry powder mixture into the first calendering roll gap, wherein the processing equipment is preferably selected from an extruder, a jet mill, a pin mill, an impact mill, a mortar mill, a roller mill, and combinations thereof; or first supply the removed area of ​​the dry film to the dry powder mixture and / or the dry mixture, wherein the system is configured to supply the dry powder mixture and / or the dry mixture to the first calendering roll gap, wherein the proportion of the removed area of ​​the supplied dry film relative to the total proportion of the dry powder mixture and / or the dry mixture is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, and more particularly preferably at least 10 wt.%. 16. The system according to any one of claims 10 to 15, characterized in that the first calender gap i) has a length of at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm; and / or ii) has a mask and / or funnel arranged above the calender roll gap, wherein the mask is preferably adapted to reduce the application of a certain amount of dry powder mixture and / or dry mixture to at least two opposite outer sections of the carrier roll, and optionally also to at least one intermediate region of the inner section of the carrier roll. 17. The system according to any one of claims 10 to 16, characterized in that the carrier roller and / or the counterweight roller a) has a diameter less than or equal to 100 cm, optionally from 10 cm to 100 cm, particularly preferably less than or equal to 50 cm, optionally from 10 cm to 50 cm, particularly less than 30 cm; and / or b) has a width greater than 30 cm, preferably greater than 60 cm, particularly preferably greater than 100 cm, and especially a maximum of 300 cm in a direction perpendicular to the roller axis of the carrier roller and / or the counterweight roller.18. The system according to any one of claims 10 to 17, characterized in that the system i) comprises a second pair of pressure rollers forming a second calendering roll gap with the carrier roller, wherein the system is configured to convey the dry film on the carrier roller into the second calendering roll gap, wherein the control unit is configured to rotate the second pair of pressure rollers about the rotation axis of the second pair of pressure rollers in a third rotational direction at a second circumferential speed greater than or equal to a first circumferential speed of the carrier roller, wherein the third rotational direction is opposite to the first rotational direction; ii) optionally, further comprising at least a third roller, preferably at least a fourth roller, particularly preferably at least a fifth roller, more preferably at least a sixth roller, and in particular at least a seventh roller; iii) optionally, configured to convey the dry film together with the substrate through at least a third calendering roll gap, preferably also through at least a fourth calendering roll gap, particularly preferably also through at least a fifth calendering roll gap, and in particular through at least a sixth calendering roll gap, wherein the calendering roll gaps are formed by two rollers respectively, wherein the two rollers are optionally arranged linearly or at an angle to each other and / or have different radii. The control unit of the system is specifically configured to set the calendering roll gap width between the two rolls, and / or set the contact pressure in the corresponding calendering roll gap between the two rolls; and / or iv) optionally configured to: transfer the substrate-free dry film through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, especially at least a sixth calendering roll gap, due to the increase in circumferential speed. 19. A dry film arranged as at least one strip, preferably a plurality of parallel strips, wherein, on a substrate, the at least one strip, preferably the plurality of parallel strips, are each defined by two boundary lines in the longitudinal direction of one or more strips, characterized in that the boundary lines are substantially straight and substantially parallel to each other, wherein the distance between the corresponding two boundary lines varies in the longitudinal direction by less than or equal to 1000 μm, preferably less than or equal to 500 μm, particularly preferably less than or equal to 200 μm.20. The dry film according to claim 19, characterized in that each of the at least one strip, preferably a plurality of parallel strips, i) has a length in the longitudinal direction of one or more strips of at least 0.1 m, preferably at least 0.5 m, particularly preferably at least 1 m, more particularly preferably at least 5 m, especially at least 10 m; and / or ii) has a width perpendicular to the longitudinal direction of one or more strips of at least 200 mm and / or a maximum of 1200 mm, preferably 250 mm to 650 mm, particularly preferably 250 mm to 350 mm; and / or iii) has a wavy pattern extending in the longitudinal direction of one or more strips of the dry film and extending perpendicular to the longitudinal direction of one or more strips of the dry film between substantially straight and substantially parallel boundary lines of one or more strips of the dry film, wherein preferably, the waves of the wavy pattern have a periodic spacing greater than 0 mm and less than 10 mm, preferably greater than 0 mm and less than 5 mm, in the transverse direction of one or more strips; The dry film is optionally arranged on the substrate as at least two parallel strips, preferably at least three parallel strips, particularly preferably at least four parallel strips, and especially at least five parallel strips. Claims 6 / 8, page 7, CN 121152689 A 21. The dry film according to any one of claims 19 or 20, characterized in that an undercoating layer is disposed in at least some areas between the dry film and the substrate, the undercoating layer contacting both the dry film and the substrate, wherein preferably, i) the undercoating layer comprises or is composed of a polymer and a conductive material, and / or the thickness of the undercoating layer is less than 10 μm, particularly preferably less than 2 μm; and / or ii) the substrate comprises or is composed of a three-dimensional structure, preferably comprising woven fabric, non-woven fabric and / or stretched mesh or composed of woven fabric, non-woven fabric and / or stretched mesh; and / or iii) the substrate has a texture, preferably prepared by etching, sandblasting and / or laser processing, wherein the texture is particularly present on the surface of the substrate facing the dry film; and / or iv) the substrate comprises or is composed of a porous layer, wherein the porous layer preferably comprises an electrode layer and / or a granular layer or is composed of an electrode layer and / or a granular layer.22. The dry film according to any one of claims 19 to 21, characterized in that the dry film comprises an active material for a battery electrode, wherein the active material is preferably i) selected from active materials for a battery cathode and active materials for a battery anode, wherein the active material is particularly preferably selected from lithium iron phosphate, lithium manganese iron phosphate, lithium manganese oxide, lithium nickel manganese cobalt oxide, nickel-rich lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminum oxide, lithium cobalt oxide, lithium manganese nickel oxide, high-pressure spinel, carbon, sulfur, graphite, hard carbon, silicon, tin, silicon oxide, lithium, lithium indium titanate, sodium-containing compounds based on metal oxides, polyanions, Berlin blue analogues, and combinations thereof; and / or ii) the mass fraction of the active material contained in the dry film relative to the total mass of the dry film is greater than 50 wt.%, preferably greater than 70 wt.%, particularly preferably greater than 90 wt.%; i) the liquid content in the dry film is less than or equal to 1 vol% relative to the total volume of the dry film. 23. The dry film according to any one of claims 19 to 22, characterized in that the dry film comprises a conductive additive, wherein the conductive additive is preferably i) selected from carbon nanotubes, carbon particles, graphite, graphene, porous carbon, and combinations thereof; and / or ii) the mass fraction of the conductive additive contained in the dry film relative to the total mass of the dry film is 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, particularly preferably 1 wt.% to 4 wt.%. 24. The dry film according to any one of claims 19 to 23, characterized in that the dry film comprises a non-fibrillated material that produces an adhesion effect, wherein the material is preferably i) selected from fluoropolymers, carboxymethyl cellulose, styrene-butadiene rubber, biopolymers, polyolefins, polypeptides, polyamides, polyacrylates, and mixtures thereof; and / or ii) the mass fraction of the non-fibrillated material contained in the dry film relative to the total mass of the dry film is 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, particularly preferably 0.5 wt.% to 4 wt.%.25. The dry film according to any one of claims 19 to 24, characterized in that the dry film comprises a fibrillating material that produces an adhesion effect, wherein the fibrillating material is preferably i) selected from fibrillating peptides, fibrillating plastics and mixtures thereof, wherein the fibrillating material is particularly preferred to be fibrillable PTFE with a molecular weight greater than 106 g / mol, most preferably greater than 107 g / mol; and / or ii) the mass fraction of the fibrillating material contained in the dry film relative to the total mass of the dry film is greater than 1 wt.%, preferably greater than 10 wt.%, particularly preferably greater than 50 wt.%; and / or iii) comprises or is composed of a fibrous structure, the fibrous structure having a diameter of 0.001 μm to 1 μm and / or a length of 1 μm to 100 μm; and / or claims 7 / 8 pages 8 CN 121152689 A iv) isotropically distributed in the dry film; and / or v) anisotropically distributed in the dry film. 26. The dry film according to any one of claims 19 to 25, characterized in that the dry film comprises an ion-conducting material, wherein the ion-conducting material is preferably i) selected from ion-conducting solids, gel-like ion conductors, salt-like ion conductors, and mixtures thereof, wherein the ion-conducting solid is preferably selected from sulfide solid ion conductors, glassy solid ion conductors, polymer solid ion conductors, ceramic solid ion conductors, and mixtures thereof; and / or ii) the mass fraction of the ion-conducting material present in the dry film relative to the total mass of the dry film is 1 wt.% to 99 wt.%, preferably 5 wt.% to 30 wt.%, particularly preferably 10 wt.% to 20 wt.%. 27. The dry membrane according to any one of claims 19 to 26, characterized in that the dry membrane i) has a layer thickness of 5 μm to 500 μm, preferably 10 μm to 150 μm, particularly preferably 30 μm to 100 μm, more preferably 40 μm to 70 μm; and / or ii) the liquid content in the dry membrane is less than or equal to 1 vol.% relative to the total volume of the dry membrane; and / or iii) the porosity is 15% to 80%, preferably 20% to 50%, particularly preferably 25% to 35%, or the porosity is 0.1% to 25%, preferably 0.1% to 10%, particularly preferably 0.1% to 5%. 28. The dry membrane according to any one of claims 19 to 27, characterized in that the dry membrane is prepared by the method according to any one of claims 1 to 9. 29. A battery comprising: a) an electrode comprising or composed of the dry membrane according to any one of claims 19 to 28; b) a counter electrode; and c) an electrolyte, preferably a solid electrolyte, disposed between the electrode and the counter electrode.Claims 8 / 8, page 9, CN 121152689 A Method and system for preparing a dry film, a dry film, and a battery comprising the dry film

[0001] A method for preparing a dry film, a system for preparing a dry film, a dry film, and a battery comprising the dry film are provided. The method and system are characterized by using at least two processing devices, each processing device being arranged opposite to the outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, each of the at least two processing devices being adapted to remove the area of ​​the dry film supported on the carrier roller and located at the outer section of the carrier roller. The method and system enable the rapid and energy-efficient preparation of segmented strip dry films with extremely high edge precision.

[0002] In the prior art, it is known to coat the arester foil of the battery electrode with a slurry film comprising electrode active material, binder, and conductive additives in a slurry process (i.e., wet chemistry). For efficient preparation, a wider film is coated on the conductive arester foil as a substrate. It is generally desirable that the coating width is a multiple of the dimensional width of the electrode made from the substrate with the film. For example, a film width of 300 mm is specified here, from which a sheet of 100 mm in length is cut to produce, for example, an electrode specification of 300 mm wide × 100 mm long. For example, for the preparation of electrodes with segmented coatings (zebra coatings), a slot die with spacers is used, which allows coating over a larger width and prevents slurry from overflowing from the slot die at the mask area, thereby creating uncoated areas through the spacers. So-called intermittent coating, which has uncoated areas at regular intervals along the coating direction, can also be produced by controlling the slurry flow rate through the nozzle opening.

[0003] Furthermore, in the prior art, it is known to coat the conductive conductors of battery electrodes with a dry film containing electrode active materials, conductive additives, and binders in a dry film process (i.e., dry chemistry or dry method). This uses a dry mixture and / or dry powder mixture containing active material particles, conductive additives, and binders. A dry film refers to a coating or self-supporting film formed in a film-forming process without the use of solvents. The prepared layers or films are typically 10 μm to 1000 μm thick and consist of particles. Self-supporting dry films have a tensile strength (nominal tension) greater than 100 N / m² along their plane, enabling them to be self-supporting. Dry films with a tensile strength (nominal stress) less than or equal to 100 N / m² cannot be self-supporting and must be mechanically stabilized by rolling, substrate film, or other means. In the regions of the battery electrodes, the dry film exhibits properties comparable to layers prepared using slurry processes (layer thickness, porosity, composition, conductivity).Methods for preparing dry films are highly relevant to future battery fabrication because they can be performed faster and more energy-efficiently compared to slurry processes (e.g., no slurry evaporation is required, meaning smaller systems with lower energy requirements are possible). However, dry film processes still have drawbacks compared to slurry processes.

[0004] For example, for the fabrication of electrodes with segmented coatings (zebra coatings), it is possible to prepare individual self-supporting films and laminate them parallel to the target substrate, but this involves very high time and equipment costs and a significant amount of waste (scrap).

[0005] It is also known to use a primer layer to prepare electrodes with segmented coatings to achieve directional localized transfer of the dry film to the substrate. For example, a dry layer is prepared on a roller, which is transferred to the substrate only at points where an adhesion-promoting primer layer is provided. Therefore, the pattern of the primer layer applied to the substrate also determines the layout of the dry film layer on the substrate. This works well for some materials, but it is generally observed that a clean-edged transfer cannot be achieved depending on the cohesion or mechanical stability of the dry film layer prepared on the roller.

[0006] In addition, as known from US2017 / 040591 A1, a dry film carried on a first roll is first prepared for the preparation of an electrode with a segmented coating. The first roll and a second roll form a calender nip, wherein the second roll carries a removal film adapted to remove areas of the dry film from the first roll by applying pressure in the calender nip, thereby forming a strip-shaped dry film (zebra pattern) on the first roll. The problem with this method is that it results in high costs due to the use of the removal film, as it must be replaced and undergoes a certain meandering movement in the calender nip, i.e., a certain movement in a direction parallel to the rotation axes of the first and second rolls. As a result, the two boundary lines of the prepared dry film web extend in a wavy manner in the longitudinal direction of the dry film, at least in some areas. In other words, it is impossible to make the two corresponding boundary lines of the dry film extend as strictly parallel lines in the longitudinal direction using this method. Therefore, the edge precision of the prepared dry film can be further improved.

[0007] WO 2020 / 148410 A2 discloses a multi-roller apparatus for preparing dry film, wherein, at the end of the process, the edge of the dry film is trimmed on the last roll of the multi-roller apparatus. Trimming the edge on the last roll of the multi-roller apparatus has several disadvantages. First, the dry film is already very dense at this point, which makes edge trimming more energy-intensive and leads to greater wear on the cutting tool. Second, the distance from the cutting device to the first calendering roll gap of the multi-roller apparatus is very large, which prolongs the conveying path from the cutting device to the first calendering roll gap (e.g., the conveying path of the cut dry film material).Third, there is a risk that the resulting unclear edges (low parallelism or abrasion areas) of the dry film may fold during transport, resulting in different layer thicknesses or laminations before the unclear edges are trimmed.

[0008] Another challenge of the dry film process is that a large coating width (i.e., a width of at least 300 mm perpendicular to the longitudinal direction of the dry film) means that the rollers used for post-calendering (post-compaction) must be very large and robust to withstand higher linear loads, with the linear load under wide coatings being correspondingly greater than that under narrow coatings.

[0009] Based on this, the object of the present invention is to provide a method for preparing a dry film, a system for preparing a dry film, a dry film, and a battery comprising the dry film, which overcomes at least one, preferably all, disadvantage of the prior art.

[0010] This object is achieved by a method having the features of claim 1, a system having the features of claim 10, a dry film having the features of claim 19, and a battery having the features of claim 29. The dependent claims describe advantageous improvements.

[0011] According to the present invention, a method for preparing a dry film is provided, comprising feeding a dry powder mixture and / or a dry mixture into a first calendering roll gap formed by a carrier roller and a first pair of pressure rollers, wherein the carrier roller rotates about a carrier roller rotation axis at a first circumferential speed along a first rotation direction, and the pressure rollers rotate about a pressure roller rotation axis at a second circumferential speed lower than the first circumferential speed along a second rotation direction, wherein the second rotation direction is opposite to the first rotation direction, wherein the dry powder mixture and / or the dry mixture passes through the calendering roll gap in a conveying direction and forms a dry film supported on the carrier roller in at least some areas.

[0012] The invention is characterized by using at least one first processing device arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller; and using at least one second processing device arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, wherein the carrier roller has an inner section located between the first and second outer sections in a direction parallel to the axis of rotation of the carrier roller, wherein the first and second processing devices are each adapted to remove the area of ​​the dry film supported on the carrier roller and located at the outer section of the carrier roller (preferably at least by cutting, more preferably by removal, for example by a removal unit).

[0013] The dry powder mixture can be in the form of a free-flowing powder. The dry mixture can exist as a cohesive, non-flowable bulk material, as a flat agglomerate, or (already) as a dry film (e.g., a strip dry film). In principle, it is conceivable not to consider the dry powder mixture and the dry mixture as two different substances, but rather to consider the dry powder mixture as a special embodiment of the dry mixture.In this context, the term "dry powder mixture and / or dry mixture" can be simplified to the term "dry mixture," where the dry powder mixture is a specific form (species) of the dry mixture (genus). Then, the dry mixture can be in the form of a free-flowing powder (because it can be a dry powder mixture). Specification 2 / 22 pages 11 CN 121152689 A

[0014] Using the method according to the invention (dry film process), segmented strip dry films with extremely high edge precision can be provided in a rapid and energy-efficient manner. High edge precision is understood to mean that the strip formed from the dry film (or all strips formed from the dry film) is defined by two boundary lines in the longitudinal direction of the strip, the boundary lines being substantially straight and substantially parallel to each other. "Substantially straight and substantially parallel to each other" can be understood as the variation in distance between the corresponding two boundary lines in the longitudinal direction being less than or equal to 1000 μm, preferably less than or equal to 500 μm, and particularly preferably less than or equal to 200 μm. According to the invention, the dry film, particularly a non-self-supporting coating or layer (tensile strength in the coated plane less than or equal to 100 N / m2) or a self-supporting film (tensile strength in the coated plane greater than 100 N / m2), is produced by a film-forming process without the use of solvents, i.e., in particular, no solvent is used in the method according to the invention.

[0015] The method according to the invention is highly relevant to the layer preparation of battery electrodes (lithium-ion batteries, solid-state batteries, lithium-sulfur batteries, sodium-ion batteries), and also to other coatings, such as those used for energy storage devices (e.g., supercapacitors, fuel cells), electrochemical components (e.g., for electrolysis or catalyst layers), or adsorption layers formed of porous materials.

[0016] In a preferred embodiment of the method, the first processing device and the second processing device are each adapted to remove, at least by cutting (preferably also by removal, e.g. by a removal unit of the system), the region of the dry film supported on the carrier roller and on the outer section of the carrier roller, without any movement of the first processing device and the second processing device themselves, which in particular means here that the first processing device and the second processing device remain stationary in the method (i.e., do not move relative to the carrier roller). This is also applicable to other, preferably all, processing equipment used in the method according to the invention. This embodiment can further improve high edge accuracy, i.e., the strictness of the straightness and parallelism of the two boundary lines of the dry film prepared by this method.

[0017] In this method, the dry film can be transferred to a carrier roller without a substrate. This method can be used to prepare a self-supporting dry film, i.e., a dry film that is not stored on a substrate. In a downstream step of this method, the self-supporting dry film can be applied to a substrate. The substrate can have a three-dimensional structure (e.g., fabric, felt, or expanded metal).Furthermore, the substrate can be textured (e.g., etched, sandblasted, or laser-treated). Additionally, the substrate can include or consist of a porous layer (e.g., an electrode layer or a granular layer). Layers applied to the substrate can be applied using a slurry process or a dry film process. An undercoat can be present between the substrate and the dry film, supporting (i.e., reinforcing) the bond between the dry film and the substrate.

[0018] Alternatively, during the method according to the invention, a dry film can be laminated onto the substrate. This method can be used to prepare a dry film laminated onto a substrate. In this case, the substrate can also have a three-dimensional structure (e.g., fabric, fiber felt, or stretched mesh). Furthermore, the substrate can be a textured substrate (e.g., etched, sandblasted, or laser-treated substrate). Additionally, the substrate can include or consist of a porous layer (e.g., an electrode layer or a granular layer). Layers applied to the substrate can be applied using a slurry process or a dry film process. Before laminating the dry film, the substrate can have an undercoat to support the bond between the dry film and the substrate. However, in this embodiment, the dry film can also be removed from the substrate again (at the end of the method) to provide a self-supporting dry film. Removing the substrate from the dry film may be useful (e.g., for use in batteries) if the substrate on which the dry film is laminated during the method according to the invention does not contain or is not composed of any conductive material, i.e., is unsuitable as a substrate for use, for example, in batteries.

[0019] The substrate may not contain or be composed of conductive material, or may contain or be composed of conductive material, wherein the conductive material is preferably selected from metals, carbon, and combinations thereof. The term "metal" also includes metal alloys.

[0020] The substrate can have an undercoat in at least some areas to enhance the adhesion of the dry film. The undercoat can comprise a polymer (or binder, such as a thermoplastic material) and a conductive material (e.g., a carbon-containing material, such as carbon black, graphite, or similar materials) or consist of the polymer and the conductive material. The thickness of the undercoat is preferably less than 10 μm, particularly preferably less than 2 μm. Preferably, the base coating, as described on page 3 / 22 of CN 121152689 A, is arranged on the substrate in a direction perpendicular to the axis of rotation of the carrier roller, in a region opposite the inner section of the carrier roller. The advantage of the base coating is that it increases the adhesion between the dry film and the substrate in the area where the base coating is applied. In the case of thermoplastic polymer materials, activation of the polymer in the base coating, such as through heating (e.g., by heating the roller or an external heat source such as an infrared radiator), softens the base coating. In this way, the dry film particles are pressed into the base coating, resulting in an increased contact area between the dry film particles and the base coating. When the base coating cools (away from the heating zone or with the heat source turned off), the base coating solidifies, and the increased contact area with the dry film particles pressed into the base coating causes the dry film to bond to the substrate where the base coating is applied.The areas of the substrate without the base coating do not have an increased interface, and therefore the adhesion to the dry film is not increased, meaning that the dry film preferably does not adhere to these areas. Therefore, the base coating can further improve the edge precision of the prepared dry film, which also enables intermittent coating.

[0021] Similar to the base coating, rough or three-dimensional substrates (e.g., fiber felt, wire mesh, stretched mesh, and / or textured substrates, such as etched substrates, sandblasted substrates, laser-treated substrates, etc.) can be used. The substrate surface (e.g., a textured surface, such as an etched, sandblasted, and / or laser-treated surface) can locally increase adhesion and thus improve edge precision. In this case, if the surface roughness Ra is greater than 1 μm, preferably greater than 5 μm, particularly preferably greater than 10 μm, the adhesion increases, while the roughness Ra of areas of the substrate with lower adhesion to the dry film is less than 1 μm.

[0022] The substrate can have a three-dimensional structure or be composed of a three-dimensional structure in at least some regions, wherein the substrate preferably comprises woven fabric, non-woven fabric and / or stretched mesh, or is composed of woven fabric, non-woven fabric and / or stretched mesh.

[0023] Furthermore, the substrate can have a texture in at least some regions, wherein the texture is preferably prepared by etching, sandblasting and / or laser processing. In particular, the texture exists on the surface of the substrate facing the dry film. The texture can locally increase the adhesion of the dry film, thereby improving edge accuracy.

[0024] Furthermore, the substrate can include or be composed of a porous layer in at least some regions, wherein the porous layer preferably includes or is composed of an electrode layer and / or a granular layer. Applying a porous layer with a dry film can locally increase the adhesion of the dry film, thereby improving edge accuracy. The layer applied to the substrate can be applied to the substrate using a slurry process or a dry film process.

[0025] Furthermore, by adding a particle adhesion promoter to the defined area of ​​the dry powder mixture and / or dry mixture, the adhesion of the dry film can be improved, thereby improving edge precision.

[0026] The dry powder mixture and / or dry mixture can include active materials for battery electrodes. The active material included in the dry powder mixture and / or dry mixture has a mass fraction of more than 50 wt.%, preferably more than 70 wt.%, and particularly preferably more than 90 wt.%, relative to the total mass of the dry powder mixture and / or dry mixture. The dry powder mixture can be in the form of a free-flowing powder. The dry mixture can exist as a cohesive, non-flowing bulk material, as a flat aggregate, or (already) as a dry film (e.g., a strip dry film). The active material is preferably selected from active materials for battery cathodes and active materials for battery anodes. The battery can preferably be a lithium battery or a sodium battery.The active material for the cathode can be selected from lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NMC), nickel-rich lithium nickel manganese cobalt oxide (NMC 622, NMC 811 or related NMC materials), lithium nickel cobalt aluminum oxide (NCA), lithium cobalt oxide (LCO), lithium manganese nickel oxide (LMNO), high-pressure spinel (HVS), carbon, sulfur, and combinations thereof. The active material for the anode can be selected from graphite, hard carbon, silicon, carbon, tin, silicon oxide, lithium, lithium indium titanate (LTO), and combinations thereof. Furthermore, the active material can be a sodium-containing compound based on metal oxides, polyanions (vanadates and / or phosphates), and Berlin blue analogues.

[0027] In addition, the dry powder mixture and / or dry mixture may include conductive additives, wherein the conductive additives are preferably selected from carbon nanotubes, carbon (e.g., carbon black, carbon nanotubes and / or carbon fibers), graphite, graphene, porous carbon (e.g., active carbon, page 4 / 22, CN 121152689 A), and combinations thereof. The conductive additives included in the dry powder mixture and / or dry mixture account for 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 1 wt.% to 4 wt.%, relative to the total mass of the dry powder mixture and / or dry mixture.

[0028] Furthermore, the dry powder mixture and / or dry mixture (as an adhesive or a component of an adhesive) may include a material that produces an adhesive effect in a non-fibrilized state (i.e., an "adhesive"), wherein the material is preferably selected from non-fibrilized fluoropolymers (preferably polyvinylidene fluoride PVDF, ethylene-tetrafluoroethylene copolymer ETFE and / or polytetrafluoroethylene PTFE), carboxymethyl cellulose CMC, styrene-butadiene rubber SBR, biopolymers, polyolefins (e.g., polyethylene, preferably polyethylene with a molecular weight greater than 1,000,000 g / mol), polypeptides (e.g., sericin), polyamides, polyacrylates, and mixtures thereof. In this case, the adhesive effect is independent of the formation of a fibril network (non-fibrilized adhesive). The proportion of this material included in the dry powder mixture and / or dry mixture relative to the total mass of the dry powder mixture and / or dry mixture is 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 0.5 wt.% to 4 wt.%.

[0029] In particular, the dry powder mixture and / or dry mixture (as a binder or a component of a binder) may include a fibrillable material that is fibrillable under mechanical, thermal, and / or physicochemical influences and may also produce an adhesive effect (i.e., it may also be a "binder"), wherein the material is preferably selected from polypeptides (e.g., sericin), plastics (e.g., fluoropolymers such as PTFE, and / or polyolefins with a molecular weight greater than 1,000,000 g / mol, such as polyethylene with a molecular weight greater than 1,000,000 g / mol) and mixtures and combinations thereof (fibrillable binders). The mechanical shear forces in the calendering roll gap enable the material to form fibrils, which increase the mechanical stability of the dry film by forming a stable network. In particular, the term "fibril" refers to a thread-like structure with a diameter preferably from 0.001 μm to 1 μm and / or a length from 1 μm to 100 μm. The proportion of fibrillable material included in the dry powder mixture and / or dry mixture relative to the total mass of the dry powder mixture and / or dry mixture is less than or equal to 10 wt.%, preferably less than or equal to 5 wt.%, particularly preferably less than or equal to 2 wt.%, more particularly preferably 0.3 wt.% to 2 wt.%, and optionally 1 wt.% to 2 wt.%.

[0030] Due to the storage of the dry film prepared on the roller, the binder in the dry powder mixture and / or dry mixture may be present in a proportion of less than or equal to 10 wt.%, preferably less than or equal to 5 wt.%, particularly preferably less than or equal to 2 wt.%, more particularly preferably 0.3 wt.% to 2 wt.%, and optionally 1 wt.% to 2 wt.%, relative to the total weight of the dry powder mixture and / or dry mixture. Optionally, the proportion of binder in the dry powder mixture and / or dry mixture relative to the total weight of the dry powder mixture and / or dry mixture is greater than or equal to 0.1 wt.%.

[0031] Activation of adhesion effects (e.g., the formation of fibrils in PTFE or point-to-point adhesion effects in PVDF or polyolefins) can be achieved by thermal, mechanical, and / or chemical means. The activation process can be pre-formed in upstream process steps or generated only in the calender roll gap.

[0032] For upstream activation, grinding or mixing processes can be used, wherein shear forces act on the dry powder mixture and / or dry mixture, particularly the binder, due to particle-to-particle collisions or collisions with mechanical elements. Mills such as pin mills, jet mills, impact mills, ball mills, pulpers, mortar mills, roller mills, or mixers such as planetary mixers, Allich mixers, kneaders, single-screw extruders, and / or twin-screw extruders can be used for this purpose.

[0033] In addition to the shear force introduced into the dry powder mixture and / or the dry mixture, or the replacement of such shear force, the binder can also be activated by thermal or chemical activation (e.g., fibrillation or softening or formation of physical or chemical bonds or combinations thereof).

[0034] In the case of thermoplastic binders such as PVDF or polyolefins, activation can be achieved by heating to near or above the softening temperature. If heating is used in addition to mechanical activation, heating to well below the softening temperature may be sufficient for activation, as per specification page 5 / 22, 14 CN 121152689 A. In the case of activating fibrillable binders such as PTFE, the transition temperature must be observed. The softening temperature of fibrillable PTFE (e.g., emulsion polymerized PTFE with a high molecular weight (e.g., greater than 106 g / mol, preferably greater than 107 g / mol)) is above 300°C. However, the fibrillation of such PTFE can be thermally activated if subjected to mechanical stress above 18°C. Therefore, thermal activation combined with the application of mechanical force can be achieved at 18°C ​​to 330°C, preferably 25°C to 200°C, particularly preferably 60°C to 180°C, and even more particularly preferably 80°C to 120°C.

[0035] Conversely, treatment below 18°C ​​allows for mechanical processing (mixing, homogenization, grinding, etc.) without inducing fibrillation. This means that the adhesion effect is not released at these low temperatures, which means that the mixture is less prone to agglomeration and has good castability. After the binder has been activated, the dry powder mixture and / or dry mixture may be prone to agglomeration and no longer flow freely. If the dry powder mixture and / or dry mixture must flow freely for use in the feeding process or conveying and feeding, this may be detrimental to further process control. For example, when PTFE is activated in a jet mill, a fine dry powder mixture and / or fine dry mixture is produced that must be processed immediately, otherwise the active binder will cause agglomeration, and certain subsequent process steps will no longer be possible.

[0036] By using upstream dry powder mixing and / or dry mixing processes, the dry film material generated as waste during coating preparation can also be recovered. The rejected material (waste) is fed back into the dry powder mixture and / or dry mixture, and the proportion of rejected material added is controlled using a controlled feeding unit.

[0037] Since shear forces are also generated in the film-forming calendering roll gap between the carrier roll and the counterroller roll, the mechanical activation of the binder can also be performed independently of, or in addition to, the dry powder mixing pretreatment and / or dry mixing pretreatment. Shear forces are generated even when the same circumferential speed of the two rolls is used, thus enabling film formation. Preferably, for this purpose, a dry powder mixture and / or dry mixture in which the binder has been pre-activated (e.g., fibrillation of PTFE in the upstream process) is used.In the case of fibrillated PTFE, the fibrils may already be present in the dry powder mixture and / or dry mixture (and thus also distributed in all spatial directions of the resulting layer). By combining different types of activation, both free-flowing dry powder mixtures and poorly flowing, agglomerated dry powder mixtures and / or dry mixtures (e.g., strip dry films) can be used for film formation.

[0038] Preferably, film formation is achieved by using different circumferential speeds of the carrier roller and the counter-pressure roller, wherein, as the difference in circumferential speed increases, an additional shear force acts on the dry powder mixture and / or dry mixture in the roll gap, and additionally supports the activation of the binder. This may result in anisotropic alignment of the fibrils in the dry film. Preferably, a circumferential speed ratio of the carrier roller to the counter-pressure roller greater than 1:1, preferably greater than 2:1, particularly preferably greater than 3:1, and more particularly preferably greater than 4:1 is used. Preferably, a circumferential speed ratio of the carrier roller to the counter-pressure roller less than 20:1 is used. Due to the shear force introduced by the rollers rotating at different speeds, higher dry film compaction (=lower porosity) can be achieved under the same pressure as pure pressing (the rollers rotate at the same speed, with a speed ratio of 1:1). In the case of pure pressing, a porosity greater than 60% results in the same pressure in the film-forming step, which necessitates stronger re-compaction or higher pressure in the film-forming step, potentially leading to particle damage. However, when forming the film at different circumferential speeds according to the invention, a porosity of less than 40% can be achieved directly under the same pressure. This reduces the risk of particle damage.

[0039] The gap width used between the carrier roller and the counterweight roller can be from 5 μm to 1000 μm, preferably from 10 μm to 1000 μm, particularly preferably from 20 μm to 150 μm, especially preferably from 30 μm to 100 μm, and even more particularly preferably from 40 μm to 70 μm.

[0040] Compared to pure pressing, the method according to the invention allows for the use of lower linear loads during film formation. The linear load used can be less than 500 kN / cm (e.g., a linear load of 1 N / cm to 200 kN / cm), preferably less than or equal to 10 kN / cm (e.g., a linear load of 10 N / cm to 10 kN / cm). Since roll deformation can be avoided by using a low linear load, the carrier roll and / or the counterweight roll (film-forming roll) can have a smaller roll diameter and / or a smaller roll width.

[0041] The diameter of the carrier roll and / or the counterweight roll (film-forming roll) can be less than or equal to 100 cm (e.g., 10 cm to 100 cm), particularly preferably less than or equal to 50 cm (e.g., 10 cm to 50 cm), and especially less than 30 cm. The roll diameters of the carrier roll and one or more counterweight rolls can be different. A smaller roll diameter has the advantage of achieving a smaller dry film thickness during film formation.Therefore, a dry film thickness of 5 μm to 1000 μm, preferably 10 μm to 1000 μm, particularly preferably 20 μm to 150 μm, particularly preferably 30 μm to 100 μm, and very preferably 40 μm to 70 μm can be achieved by the method and system according to the invention.

[0042] The width of the carrier roller and / or the pressure roller (i.e., its extension in the direction perpendicular to the roller axis) can be greater than 30 cm, preferably greater than 60 cm, and particularly preferably greater than 100 cm (especially up to 300 cm).

[0043] This effect can also be enhanced by using heated rollers (e.g., heated to temperatures of 18°C ​​to 330°C, preferably 25°C to 200°C, particularly preferably 60°C to 180°C, and more particularly preferably 80°C to 120°C). This means that previously unactivated dry powder mixtures and / or previously unactivated dry mixtures can also be used for film formation. However, non-flowing or poorly flowing dry powder mixtures and / or dry mixtures (e.g., strip dry mixtures) can also be used.

[0044] If an extruder such as a twin-screw extruder is used to mix and / or pretreat the dry powder mixture and / or dry mixture and PTFE is activated by applying shear force and thermal activation, free-flowing agglomerated extrudates can be obtained. The particle size of these agglomerated extrudates can be from 50 μm to 5000 μm, preferably from 200 μm to 2000 μm, and particularly preferably from 250 μm to 750 μm. The particles are significantly larger and have a much lower tendency to further agglomerate compared to fine dry powder mixtures and / or fine dry powder mixtures that have already been pretreated in a jet mill. In this way, storable dry powder mixtures and / or storable dry mixtures can be obtained, which can be fed into the calender rolls without further processing to form a film. By avoiding overactivation of the binder (treatment at temperatures below 150°C, preferably below 120°C, with a residence time of less than 60 s, preferably less than 10 s, in the kneading zone of the extruder where shear force is applied), the extrudate can have relatively low hardness, which allows for good processing at relatively low pressure in the calender roll gap.

[0045] Furthermore, the dry powder mixture and / or dry mixture may contain an ion-conducting material, preferably an ion-conducting solid (solid electrolyte). The ion-conducting material is preferably selected from ion-conducting solids (solid electrolytes), gel-like ion conductors, salt-like ion conductors, and mixtures thereof (preferably lithium-ion conduction and / or Na-ion conduction).The ion-conducting solid is preferably selected from sulfide solid ion conductors (e.g., lithium thiophosphate, LPS, argyrodite, LPSCl and / or LGPS, or corresponding sodium ion-conducting sulfide solid ion conductors), glassy solid ion conductors (e.g., LiAlSiO4 or NaAlSiO4), polymer solid ion conductors (e.g., PEO), ceramic solid ion conductors (e.g., LLZO or corresponding sodium ion-conducting ceramic solid ion conductors), and mixtures thereof. The proportion of solid electrolyte included in the dry powder mixture and / or the dry powder mixture relative to the total mass of the dry powder mixture can be 1 wt.% to 99 wt.%, preferably 5 wt.% to 30 wt.%, particularly preferably 10 wt.% to 20 wt.%.

[0046] The liquid content of the dry powder mixture and / or the dry mixture relative to the total volume of the dry powder mixture and / or the dry mixture can be less than or equal to 1 volume (vol.)%.

[0047] In this method, the inner section, the first outer section, and the second outer section of the carrier roller can each be freely defined by two mutually parallel boundary lines spanning the circumference of the carrier roller. Preferably, at least one boundary line of the inner section is located on the boundary line of the first outer section and / or the second outer section. In other words, the inner section is directly connected to the first outer section and / or the second outer section, i.e., in contact with the first outer section and / or the second outer section.

[0048] The inner section of the carrier roller may have a surface finish to which a dry film adheres in at least some areas (e.g., an adhesive coating on the surface of the carrier roller and / or a texture on the surface of the carrier roller, such as a texture prepared by etching, sandblasting, and / or laser processing, optionally regular or irregular), wherein the first outer section and / or the second outer section of the carrier roller have a surface finish to which a dry film does not adhere, wherein the surface finish is preferably designed as a smooth surface as described on page 7 / 22 of the specification of the carrier roller, 16 CN 121152689 A. The center roughness value Ra of the smooth surface can be less than or equal to 50% of the center roughness value Ra of the carrier roller in the inner section. The center roughness value Ra of the smooth surface is 0.001 μm to 1 μm. The center roughness value Ra of the surface of the inner section of the carrier roller can be greater than 50% of the center roughness value Ra of the smooth surface of the carrier roller, preferably having a center roughness value of 0.1 μm to 10 μm. The advantage of this embodiment is that the adhesion force of the dry film to the carrier roller is reduced in areas where the dry film should not adhere to the carrier roller. In other words, the first and second processing devices only need to remove a small amount of dry film from the carrier roller at least by cutting, that is, the unattached dry film can be returned to the first calendering roll gap (as dry powder mixture and / or dry mixture) earlier in the process, which makes the process more efficient and can also shorten the maintenance interval of the processing devices.

[0049] Furthermore, the inner section of the carrier roller may have a surface quality to which a dry film adheres in at least some areas (e.g., an adhesive coating on the surface of the carrier roller and / or a texture on the surface of the carrier roller, such as a texture prepared by etching, sandblasting and / or laser processing, optionally regular or irregular), wherein the first outer section and / or the second outer section of the pressure roller have a surface quality to which a dry film does not adhere, wherein the first outer section of the pressure roller is arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, and the second outer section of the pressure roller is arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller. Preferably, the surface quality of the first outer section and / or the second outer section of the pressure roller is designed as a concave surface of the pressure roller, the radius of which is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, and especially less than or equal to 90% of the radius of the pressure roller in the first region of the inner section of the pressure roller. The surface quality to which the dry film of the first outer section and / or the second outer section of the pressure roller does not adhere can also be designed as a coating (e.g., comprising DLC ​​and / or PTFE or a coating composed of DLC and / or PTFE) on the first outer section and / or the second outer section of the pressure roller, which reduces the adhesion force on the pressure roller (preferably the amount of dry film adhered is at least 1 wt.%, particularly at least 10 wt.%, less than the inner section of the carrier roller), preferably with no adhesion force. Alternatively or additionally, the surface quality to which the dry film of the carrier roller adheres to the inner section can be designed as a coating and / or texture on the inner section of the carrier roller, which allows adhesion to the carrier roller. The coating can be an adhesive coating on the surface of the inner section of the carrier roller. The texture can be produced by etching, sandblasting, and / or laser processing (optionally regular or irregular). The center roughness value Ra of the surface of the inner section of the carrier roller can be greater than 50% of the center roughness value Ra of the surface of the first outer section and / or the second outer section of the pressure roller, preferably having a center roughness value of 0.1 μm to 10 μm. The coating of the inner section of the carrier roller and / or the first outer section and / or the second outer section of the pressure roller can comprise or consist of materials selected from or composed of materials selected from: PTFE, DLC, tungsten carbide, hard chrome, and combinations thereof. An advantage of this embodiment is that the adhesion of the dry film to the carrier roller is reduced in areas where the dry film should not adhere. In other words, the first and second processing devices only need to remove a small amount of dry film from the carrier roller at least by cutting; that is, the unattached dry film can be returned to the first calendering roll gap earlier in the process (as a dry powder mixture and / or dry mixture), making the process more efficient and also shortening the maintenance intervals of the processing devices.

[0050] Optionally, the carrier roller has at least one second region of the inner section, the shape of which is similar to the first and / or second outer sections of the carrier roller, i.e., the radius of its concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, especially less than or equal to 90%, of the radius of the pressure roller in the first region of the inner section.

[0051] The first processing device and the second processing device may each have a cutting unit for separating the region of the dry film supported on the carrier roller and on the corresponding outer section of the carrier roller from the region of the dry film supported on the carrier roller and on the inner section of the carrier roller by cutting (i.e., the cutting of the dry film is performed along the direction of the strip conveying the dry film on the carrier roller). Separation by cutting has the advantage of being highly certain that the boundary line of the dry film (i.e., the edge of the dry film) will not be wavy or burr-like in the longitudinal direction, at least in some areas, compared to separation by applying pressure through moving the film (e.g., the method in US2017 / 040591 A1). In other words, it can be ensured with high certainty that the edge of the dry film extends straight and parallel to each other along its length. Therefore, the edge accuracy of the prepared dry film is improved.

[0052] The cutting unit is preferably selected from a roller cutter, an air nozzle, a laser, and combinations thereof. The roller cutter and the laser can also be used to cut dry films with strong adhesion. The roller cutter may include a material with a Vickers hardness (e.g., HV10) lower than that of the material on the surface of the carrier roller (e.g., chromium as the material of the carrier roller) (e.g., brass as the material of the roller cutter). Its advantage is that wear on the carrier roller can be reduced. Air nozzles are particularly suitable if the area of ​​dry film to be cut is located on a roller section (e.g., the first and / or second outer sections) with a surface quality to which the dry film will not adhere, because the lower cutting force of the air nozzle is sufficient to cut dry film residue adhering to the carrier roller, despite the carrier roller having a non-adhering surface quality. Other advantages of air nozzles include their low-maintenance operation, easy adjustment of air speed for different dry film thicknesses, and no damage to dry film formation or structure, as there is no material buildup near the cutting edge (e.g., dry film material buildup on the blades of a roller) unlike with a rotary cutter. Lasers offer the advantage of non-contact cutting, thus being gentler on the carrier roller surface than, for example, a rotary cutter, allowing for a longer and more economical process. Furthermore, lasers prevent dry film material buildup near the cutting edge, whereby dry film formation or structure remains unaffected. In this method, the on / off state and effective force of the cutting unit of the corresponding processing equipment (e.g., the pressure of the roller cutter, the airflow intensity of the air nozzle, and / or the radiation intensity of the laser) can be controlled.

[0053] The cutting unit may have a positioning system. This can improve edge accuracy, for example, improve the positioning of the cutting unit on the substrate film. The positioning system may have a detector for detecting positioning. In addition, the positioning system may have a traversing unit for positioning the cutting unit. Furthermore, the positioning system may have a control unit (separate from the system according to the invention) configured to control or adjust the positioning system, preferably the traversing unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention may be configured to control or adjust the positioning system, preferably the traversing unit of the positioning system. Adjustment can be made through information feedback (“feedback” mechanism) from the detector of the positioning system.

[0054] Furthermore, the first processing device and the second processing device may each have a removal unit for removing areas of the dry film supported on the carrier roller and on corresponding outer sections of the carrier roller.

[0055] Furthermore, the first processing device and the second processing device may each have an additional removal unit for removing areas of the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction.

[0056] The removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof. Scrapers and brushes have the advantage of also removing dry film firmly adhered to the carrier roller. Air nozzles or suction devices are particularly suitable if the area of ​​the dry film to be cut is located on a roller segment (e.g., the first outer segment and / or the second outer segment) with a surface quality to which the dry film will not adhere, because the lower removal force of the air nozzles or suction devices is sufficient to cut dry film residues adhered to the carrier roller, even though the carrier roller has a non-adhering surface quality. Another advantage of suction devices is that the extracted dry film material (within the suction channel) can be easily transported back to the calendering roll gap (return of dry film material), which avoids waste of dry film material and makes the process more economical. Since the processing equipment with the removal unit is arranged opposite the first outer segment of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, the transport path of the removed dry film material to the calendering roll gap of the carrier roller is also short, making transport faster and more energy-efficient. In this method, the on / off state and force of the removal unit of the corresponding processing device on the carrier roller (e.g., airflow intensity of the air nozzle, brush pressure, and / or suction flow intensity of the suction device) can be controlled.

[0057] The distance unit and / or additional distance units may have a positioning system. This can improve edge accuracy, for example, improve the positioning of the removal unit on the substrate film. The positioning system may have a detector for detecting positioning. Furthermore, the positioning system may have a lateral movement unit for positioning the distance unit.Furthermore, the positioning system may have a control unit (separate from the system according to the invention) configured to control or adjust the positioning system, preferably the lateral movement unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention may be configured to control or adjust the positioning system, preferably the lateral movement unit of the positioning system. Adjustment may be made by information feedback (“feedback” mechanism) from the detectors of the positioning system.

[0058] The inner section of the carrier roller may be divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer (e.g., 1, 2, 3, 4, 5, or 6), and an intermediate region is arranged between each two adjacent inner section regions, the boundaries of which are defined by two opposing boundary lines of the 2n boundary lines in the direction of the rotation axis of the carrier roller. The at least two inner section regions may have a surface quality to which the dry film adheres, and the intermediate region preferably has a surface quality to which the dry film does not adhere. This has the advantage that a dry film with a striped pattern (zebra pattern) can also be prepared in the inner section of the carrier roller.

[0059] In a preferred embodiment, in a direction perpendicular to the axis of rotation of the carrier roller, additional processing equipment can be used, each corresponding to a middle region of the inner section, which is adapted to remove, at least by cutting (i.e., cutting the dry film along the direction of the strip conveying the dry film on the carrier roller), the region of the dry film supported on the carrier roller and located in the middle region of the carrier roller. This has the advantage that a dry film with a striped pattern (zebra pattern) can also be prepared in the inner section of the carrier roller. By removing the dry film by cutting, high edge precision can be achieved.

[0060] Each of the additional processing equipment may include a cutting unit for separating the region of the dry film at the corresponding middle region of the carrier roller supported on the carrier roller from the portion of the dry film at the inner section of the carrier roller supported on the carrier roller by cutting. The cutting unit is preferably selected from a roller cutter, an air nozzle, a laser, or a combination thereof. In this method, the on / off state and force (e.g., the pressure of the roller cutter, the airflow intensity of the air nozzle, and / or the radiation intensity of the laser) of the cutting unit of the corresponding additional processing equipment can be controlled. The cutting unit may have a positioning system, which optionally has at least one of the features described above.

[0061] Furthermore, each of the additional processing devices may include a removal unit for removing a region of the dry film supported on and within the inner section of the carrier roller, wherein the removal unit is preferably a roller. In this method, a roller is preferably used as an additional processing device, its axis of rotation mounted parallel to the axis of rotation of the carrier roller, and its width corresponding to the width of the inner section or the inner section region. When the roller contacts the carrier roller, the dry film is transferred across the entire width of the roller for further processing or coating, and the outer section remains on the carrier roller.Then, the outer section can be removed from the outer section of the carrier roller by means of a removal unit (preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof). Several such rollers can also be arranged along the same axis of rotation to, for example, remove at least two inner section regions of the inner section of the carrier roller from the carrier roller, and transfer the at least two inner section regions onto the roller.

[0062] Furthermore, each of the additional processing devices may include a removal unit for removing the region of the dry film supported on the carrier roller and located at a corresponding intermediate region of the carrier roller, wherein the removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof. In this method, the on / off state and force of the removal unit of the corresponding processing device on the carrier roller (e.g., airflow intensity of the air nozzle, pressure of the brush, and / or suction flow intensity of the suction device) can be controlled.

[0063] The removal unit can be used, and optionally additional removal units can also be used, to feed a remote region of the dry film into the first calendering roll gap. The advantage here is that the dry film material is recycled, thus the process can be carried out more economically.

[0064] The removal unit and / or additional removal units may have a positioning system, which optionally has at least one of the features described above. Specification 10 / 22 pages 19 CN 121152689 A

[0065] For example, the removed area of ​​the dry film can be fed into a dry mixture (dry blend), which is processed into a dry powder mixture, wherein the dry powder mixture is then fed into a first calendering roll gap. Processing into a dry powder mixture preferably includes a process selected from extrusion processing, jet milling, pin milling, impact milling, mortar milling, roll milling, and combinations thereof.

[0066] Alternatively, the removed area of ​​the dry film can be fed into a dry powder mixture, which is then fed into a first calendering roll gap. The addition of dry film, the proportion of the removed area relative to the total proportion of the dry powder mixture, can be at least 0.1 wt.%, preferably at least 1 wt.%, particularly preferably at least 10 wt.%.

[0067] The dry powder mixture and / or dry mixture can be fed into the calender roll gap using a feeding and / or feeding device (e.g., a gravity feeder).

[0068] The width of the first calender roll gap (i.e., the extension in one direction along the axis of rotation of the carrier roll or the distance between the two end faces of the roll) is at least 300 mm, preferably at least 600 mm, and particularly preferably at least 1200 mm. Optionally, the maximum width of the first calender roll gap is 3000 mm. The wider the first calender roll gap, the more dry film can be produced per unit time, which increases the yield of the method according to the invention. These dimensions also apply to other calender columns.

[0069] Furthermore, the first calender roll gap may have a mask and / or funnel arranged above the calender roll gap.The advantage of a funnel or mask is that the dry powder mixture and / or dry mixture can be precisely applied to the carrier roller at the location intended to form a dry film on the carrier roller. For example, a mask or funnel can reduce the amount of dry powder mixture and / or dry mixture applied to at least the two opposite outer sections of the carrier roller, and optionally also to the inner section of the carrier roller. Therefore, the method can be performed more efficiently because the area to be coated is predefined, and almost no material binds to the uncoated areas of the carrier roller.

[0070] Laminating a dry film onto a substrate may include the following steps:

[0071] i) conveying the dry film on a carrier roller into a second calendering roll gap formed by the carrier roller and a second pair of pressure rollers, the second pair of pressure rollers rotating about the axis of rotation of the second pair of pressure rollers in a third rotational direction at a second circumferential speed higher than the first circumferential speed of the carrier roller, the third rotational direction being opposite to the first rotational direction;

[0072] ii) optionally, the dry film is also conveyed together with the substrate through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, especially at least a sixth calendering roll gap;

[0074] iii) optionally, due to the increase in circumferential speed, the dry film without substrate is conveyed by transfer through at least another third calendering roll gap, preferably at least another fourth calendering roll gap, particularly preferably at least another fifth calendering roll gap, especially at least another sixth calendering roll gap (the speed increase between the rollers may be from 1% to 1000%, preferably 5% to 100%, particularly preferably 10% to 50%).

[0075] At least one third calendering roll gap, at least one fourth calendering roll gap, at least one fifth calendering roll gap, and at least one sixth calendering roll gap can each be formed by two rolls rotating in opposite directions at different circumferential speeds. The different calendering rolls can also have different diameters. These rolls can be arranged linearly adjacent to each other. These rolls can also be arranged at an angle to each other.

[0076] An advantage of this embodiment is that the dry film is recompressed. By means of the pressure rolls and optionally at least one additional roll, the transfer of the dry film is initiated by applying additional shear force in the respective calendering roll gaps, wherein additional compaction of the dry film is achieved. This avoids any downstream calendering or the need for high pressure, thereby avoiding large roll diameters in the first calendering roll gap and / or the second calendering roll gap. Therefore, film formation and redensification or lamination can be spatially and decoupled relative to the assembly. This allows the use of less rigid or less robust assemblies and allows for angular designs instead of linear structures, where there is a risk that variations in the calendering roll gap openings will affect the roll gap openings of adjacent roll gaps.

[0077] The method may also include the step of removing the dry film from the substrate to which the dry film has been applied during the method (preferred specification 11 / 22 pages 20 CN 121152689 A, a step selected at the end of the method).In this case, a self-supporting dry film can also be obtained from the dry film initially laminated onto the substrate (during the process).

[0078] According to the invention, a system for preparing a dry film is also provided, comprising:

[0079] a) an apparatus configured to prepare a dry film from a dry powder mixture and / or a dry mixture, wherein the apparatus includes a carrier roller and a first pair of pressure rollers, wherein the carrier roller and the pressure rollers form a first calendering gap to supply the dry powder mixture and / or the dry mixture, wherein the carrier roller is adapted to rotate about a carrier roller rotation axis, and the pressure roller is adapted to rotate about a pressure roller rotation axis;

[0080] b) a control unit configured at least to rotate the carrier roller about its carrier roller rotation axis at a first circumferential speed in a first rotation direction, and to rotate the pressure roller about its pressure roller rotation axis at a second circumferential speed lower than the first circumferential speed in a second rotation direction, the second rotation direction being opposite to the first rotation direction, the control unit being specifically configured to set the gap width and / or contact pressure between the carrier roller and the first pressure roller;

[0081] The system is characterized by having at least one first processing device and at least one second processing device, the at least one first processing device being arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, and the at least one second processing device being arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, wherein the carrier roller has an inner section located between the first outer section and the second outer section in a direction parallel to the axis of rotation of the carrier roller, wherein the first processing device and the second processing device are each adapted to remove, at least by cutting (preferably also by removal, for example by a removal unit), the region of the dry film supported on the carrier roller and located at the outer section of the carrier roller.

[0082] With the system according to the invention, segmented strip dry films with very high edge precision can be provided in a fast and energy-efficient manner.

[0083] The dry powder mixture can be in the form of a free-flowing powder. The dry mixture can exist as a cohesive, non-flowing bulk material, as a flat agglomerate, or (already) as a dry film (e.g., a strip dry film). In principle, it is conceivable not to consider dry powder mixtures and dry mixtures as two different substances, but rather to consider dry powder mixtures as a specific embodiment of dry mixtures. In this case, the term "dry powder mixture and / or dry mixture" can be simplified to the term "dry mixture," where dry powder mixture is a specific form (species) of dry mixture (genus). Then, dry mixture can be in the form of free-flowing powder (because it can be a dry powder mixture).

[0084] The control unit can be configured to control the respective circumferential rotation speeds of the respective rollers and / or the ratio between the circumferential rotation speeds of the rollers.

[0085] Furthermore, the system can have a unit configured to control the respective roller spacing (i.e., the roller gap opening and / or the pressure generated in the roller gap).

[0086] The control unit and / or unit may be configured to couple the controller to the process monitoring device, such that the controller adjusts system parameters, such as circumferential speed, roll gap opening, and / or pressure, based on process monitoring values ​​(e.g., regarding coating thickness, load, homogeneity, defects, and / or edge accuracy) to maintain a predetermined coating result with a specified tolerance range.

[0087] In a preferred embodiment of the system, the first and second processing devices are each adapted to remove, at least by cutting (preferably also by removal, e.g., by the system's removal unit), the area of ​​the dry film supported on the carrier roller and on the outer section of the carrier roller without independent movement, which here specifically means that the first and second processing devices remain stationary in the system (i.e., are not configured to move relative to the carrier roller). This also applies to other, preferably all, processing devices of the system according to the invention.

[0088] If the system includes a dry powder mixture and / or a dry mixture, the dry powder mixture and / or dry mixture may have at least one of the above features as described on pages 12 / 22 of CN 121152689 A.

[0089] In a preferred embodiment, the system includes a substrate and is configured to laminate a dry film onto the substrate, wherein the substrate preferably includes a base coat in at least some regions for enhancing the adhesion of the dry film. If the system includes a substrate, the substrate may have at least one of the features described above.

[0090] The base coat may comprise or consist of an adhesive and a conductive material.

[0091] The thickness of the base coat may be less than 10 μm, preferably less than 2 μm.

[0092] Furthermore, the base coat may be arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller.

[0093] The inner section, the first outer section, and the second outer section of the carrier roller may each be freely defined by two parallel boundary lines spanning the circumference of the carrier roller. Preferably, at least one boundary line of the inner section is located on the boundary line of the first outer section and / or the second outer section. In other words, the inner section is directly connected to the first outer section and / or the second outer section, i.e., in contact with the first outer section and / or the second outer section.

[0094] The inner section of the carrier roller may have a surface quality to which a dry film adheres in at least some areas (e.g., an adhesive coating on the surface of the carrier roller and / or a texture on the surface of the carrier roller, such as a texture prepared by etching, sandblasting and / or laser processing, optionally regular or irregular), wherein the first outer section and / or the second outer section of the carrier roller have a surface quality to which a dry film does not adhere, wherein this surface quality is preferably designed as a smooth surface of the carrier roller. The center roughness value Ra of this smooth surface may be less than or equal to 50% of the center roughness value of the carrier roller in the inner section. The center roughness value Ra of the smooth surface is from 0.005 μm to 1 μm.The center roughness value Ra of the surface of the inner section of the carrier roller can be greater than 50% of the center roughness value Ra of the smooth surface of the carrier roller, preferably having a center roughness value of 0.1 μm to 10 μm.

[0095] Furthermore, the inner section of the carrier roller may have a surface quality to which dry film adheres in at least some areas (e.g., an adhesive coating on the surface of the carrier roller and / or a texture on the surface of the carrier roller, such as a texture prepared by etching, sandblasting and / or laser processing, optionally regular or irregular), wherein the first outer section of the pressure roller and / or the second outer section of the pressure roller have a surface quality to which dry film does not adhere, wherein the first outer section of the pressure roller is arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, and the second outer section of the pressure roller is arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller. Preferably, the surface quality of the first outer section and / or the second outer section of the pressure roller is designed to be a concave surface of the pressure roller, the radius of which is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, and especially less than or equal to 90% of the radius of the pressure roller in the first region of the inner section of the pressure roller. The surface quality of the first outer section and / or the second outer section of the pressure roller may alternatively or additionally be designed as a coating (e.g., comprising DLC ​​and / or PTFE or a coating composed of DLC and / or PTFE) of the first outer section and / or the second outer section of the pressure roller, which reduces the adhesion force on the pressure roller (preferably the amount of dry film adhered is at least 1 wt.%, particularly at least 10 wt.%, less than the inner section of the carrier roller), preferably no adhesion force, wherein the inner section of the carrier roller optionally has a coating to which the dry film adheres. The coating may be an adhesive coating on the surface of the inner section of the carrier roller. The coating can also be a textured coating of the inner section of the carrier roller (e.g., a textured coating produced by laser texturing and / or sandblasting, optionally regular or irregular). The center roughness value Ra of the surface of the inner section of the carrier roller can be greater than 50% of the center roughness value Ra of the surface of the first outer section and / or the second outer section of the pressure roller, preferably having a center roughness value of 0.1 μm to 10 μm. The coating particularly preferably comprises or is composed of the following materials: PTFE, DLC, tungsten carbide, hard chrome and combinations thereof.

[0096] Optionally, the carrier roller has at least one second region of the inner section, the shape of which is similar to the first outer section and / or the second outer section of the carrier roller, i.e., the radius of its concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, especially less than or equal to 90% of the radius of the pressure roller in the first region of the inner section.

[0097] The first processing apparatus and the second processing apparatus may each have a cutting unit configured to separate the region of the dry film supported on the carrier roller and on a corresponding outer section of the carrier roller from the region of the dry film supported on the carrier roller and on a corresponding inner section of the carrier roller by cutting (i.e., the cutting of the dry film is performed along the direction of the strip conveying the dry film on the carrier roller). The cutting unit is preferably selected from a roller cutter, an air nozzle, a laser, or a combination thereof. The control unit of the system may also be configured to control the on / off state and force of the cutting unit of the respective processing apparatus (e.g., the pressure of the roller cutter, the airflow intensity of the air nozzle, and / or the radiation intensity of the laser).

[0098] The cutting unit may have a positioning system. This can improve edge accuracy, for example, improve the positioning of the cutting unit on the substrate film. The positioning system may have a detector for detecting positioning. In addition, the positioning system may have a traversing unit for positioning the cutting unit. Furthermore, the positioning system may have a control unit (separate from the system according to the invention) configured to control or adjust the positioning system, preferably the traversing unit of the positioning system. Alternatively or additionally, the control unit of the system according to the invention can be configured to control or adjust the positioning system, preferably the lateral movement unit of the positioning system. Adjustment can be made via information feedback from the detectors of the positioning system (“feedback” mechanism).

[0099] Furthermore, the first and second processing devices may include a removal unit configured to remove areas of the dry film supported on the carrier roller and located at corresponding outer sections. The removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof. The control unit of the system may also be configured to control the on / off state and force (e.g., airflow intensity of the air nozzle, pressure of the brush, and / or suction flow intensity of the suction device) of the respective processing devices on the carrier roller.

[0100] Furthermore, the first and second processing devices may have another removal unit configured to remove areas of the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction.

[0101] The distance unit and / or additional distance units may have a positioning system. This can improve edge accuracy, for example, improve the positioning of the removal unit on the substrate film. The positioning system may have detectors for detecting positioning. Furthermore, the positioning system may have a lateral movement unit for positioning distance units. Additionally, the positioning system may have a control unit (separate from the system according to the invention) configured to control or adjust the positioning system, preferably the lateral movement unit. Alternatively or additionally, the control unit of the system according to the invention may be configured to control or adjust the positioning system, preferably the lateral movement unit. Adjustment can be achieved through information feedback from the detectors of the positioning system (“feedback” mechanism).

[0102] The inner section of the carrier roller can be divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and an intermediate region is arranged between each two adjacent inner section regions, the boundaries of which are defined in the direction of the rotation axis of the carrier roller by two opposing boundary lines of the 2n boundary lines.

[0103] The at least two inner section regions may have a surface quality to which dry film adheres, and the intermediate region preferably has a surface quality to which dry film does not adhere.

[0104] Furthermore, the system may have additional processing equipment in a direction perpendicular to the rotation axis of the carrier roller, respectively opposite to each intermediate region of the inner section, the additional processing equipment being adapted to remove at least by cutting the region of dry film supported on the carrier roller and located in the intermediate region of the carrier roller.

[0105] Each of the additional processing devices may have a cutting unit configured to separate the region of the dry film supported on the carrier roller at a corresponding intermediate region from the region of the dry film supported on the carrier roller at the inner section of the carrier roller by cutting (i.e., the cutting of the dry film is performed along the direction of the strip conveying the dry film on the carrier roller). The cutting unit is preferably selected from a roller cutter, an air nozzle, a laser, or a combination thereof. The control unit of the system may also be configured to control the on / off state and force (e.g., the pressure of the roller cutter, the airflow intensity of the air nozzle, and / or the radiation intensity of the laser) of the cutting unit of the corresponding additional processing device on the carrier roller. The cutting unit may have a positioning system, which optionally has at least one of the above features.

[0106] Furthermore, each of the additional processing devices may include a removal unit configured to remove the region of the dry film supported on the carrier roller and supported in the inner section of the carrier roller, wherein the removal unit is preferably a roller. In this system, a roller is preferably used as an additional processing device, its axis of rotation mounted parallel to the axis of rotation of the carrier roller and its width corresponding to the width of the inner section or inner section region. When the roller contacts the carrier roller, the dry film is transferred across the entire width of the roller for further processing or coating, and the outer section remains on the carrier roller. The outer section can then be removed from the outer section of the carrier roller by means of a removal unit (preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof). Several such rollers can also be arranged along the same axis of rotation to, for example, remove at least two inner section regions of the carrier roller from the carrier roller and transfer these at least two inner section regions onto the roller.

[0107] Furthermore, each of the additional processing devices may include a removal unit configured such that the dry film is supported on the carrier roller and located in the region of the corresponding middle region of the carrier roller. The removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof.The control unit of the system can also be configured to control the on / off state and force (e.g., airflow intensity of air nozzles, brush pressure, and / or suction flow intensity of suction devices) of the removal unit of a corresponding additional processing device on the carrier roller.

[0108] The removal unit can be configured, and optionally additional removal units can also be configured, to feed a remote region of the dry film into the first calendering roll gap. Preferably, the control unit of the system is configured to control the feeding of the remote region of the dry film into the first calendering roll gap.

[0109] The removal unit and / or additional removal units can have a positioning system, which optionally has at least one of the above features.

[0110] Optionally, the removal unit can be configured, and preferably additional removal units can also be configured, to first feed the removed region of the dry film into a dry mixture, wherein the processing device of the system is configured to process the dry mixture into a dry powder mixture, and then feed the dry powder mixture into the first calendering roll gap. The processing equipment is preferably selected from extruders, jet mills, pin mills, impact mills, mortar mills, roller mills, and combinations thereof.

[0111] Alternatively, the removal unit may be configured, and preferably additionally, to first feed the removed area of ​​the dry film into the dry powder mixture, wherein the system is configured to feed the dry powder mixture into a first calendering roll gap, wherein the proportion of the removed area of ​​the fed dry film relative to the total proportion of the dry powder mixture is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, and more particularly preferably at least 10 wt.%.

[0112] The system may have feeding and / or feeding devices (e.g., gravity feeders) suitable for feeding the dry powder mixture and / or dry mixture into the calendering roll gap.

[0113] The width of the first calendering roll gap may be at least 300 mm, preferably at least 600 mm, and particularly preferably at least 1200 mm. Optionally, the maximum width of the first calendering roll gap is 3000 mm. The wider the first calendering roll gap, the more dry film can be produced per unit time, which increases the yield of the system according to the invention. These dimensions can also be adapted to other calendering rolls in the system.

[0114] The roll gap width between the carrier roll and the counterroll can be from 5 μm to 1000 μm, preferably from 10 μm to 1000 μm, particularly preferably from 20 μm to 150 μm, especially preferably from 30 μm to 100 μm, and even more particularly preferably from 40 μm to 70 μm.

[0115] Compared to pure pressing, the system according to the invention also allows for the use of lower linear loads during film formation.The system control unit can be configured to apply a linear load of less than 500 kN / cm (e.g., applying a linear load of 1 N / cm to 200 kN / cm, see page 24 of the specification 15 / 22 CN 121152689 A), preferably applying a linear load of less than or equal to 10 kN / cm (e.g., applying a linear load of 10 N / cm to 10 kN / cm). Since roll deformation can be avoided by using a low linear load, the carrier roll and / or the counterweight roll (film forming roll) can have a small roll diameter and / or a small roll width.

[0116] The diameter of the carrier roll and / or the counterweight roll (film forming roll) can be less than or equal to 100 cm (e.g., 10 cm to 100 cm), particularly preferably less than or equal to 50 cm (e.g., 10 cm to 50 cm), especially less than 30 cm. The roll diameters of the carrier roll and one or more counterweight rolls can be different. A smaller roll diameter has the advantage of achieving a lower dry film thickness during film formation. Therefore, dry film thicknesses of 5 μm to 1000 μm, preferably 10 μm to 1000 μm, particularly preferably 20 μm to 150 μm, particularly preferably 30 μm to 100 μm, and very preferably 40 μm to 70 μm can be achieved using the method and system according to the invention.

[0117] The width of the carrier roller and / or the counterweight roller (i.e., its extension in the direction perpendicular to the roller axis) can be greater than 30 cm, preferably greater than 60 cm, and particularly preferably greater than 100 cm (especially up to 300 cm).

[0118] The system can be configured to heat the roller (e.g., via the system's heating element). The system's control unit can be configured to heat the roller to a temperature of 18°C ​​to 330°C, preferably 25°C to 200°C, particularly preferably 60°C to 180°C, and more particularly preferably 80°C to 120°C. This means that previously unactivated dry powder mixtures and / or previously unactivated dry mixtures can also be used for film formation. However, non-flowing or poorly flowable or poorly free-flowing dry powder mixtures and / or dry mixtures (e.g., strip dry mixtures) may also be used.

[0119] Furthermore, the first calendering roll gap may have a mask and / or funnel arranged above the calendering roll gap. Preferably, the mask is adapted to reduce a certain amount of dry powder mixture and / or dry mixture applied to at least two opposite outer sections of the carrier roll, and optionally also to at least one intermediate region of the inner section of the carrier roll.

[0120] The system may include a second pair of pressure rolls forming a second calendering roll gap with the carrier roll, wherein the system is configured to convey a dry film on the carrier roll into the second calendering roll gap, wherein the control unit is configured to cause the second pair of pressure rolls to rotate about the second pair of pressure rolls axis of rotation in a third rotational direction at a second circumferential speed higher than a first circumferential speed of the carrier roll, wherein the third rotational direction is opposite to the first rotational direction.

[0121] The system may also include at least one third roll, preferably at least one fourth roll, particularly preferably at least one fifth roll, most preferably at least one sixth roll, and especially at least one seventh roll.

[0122] Furthermore, the system may be configured to convey the dry film together with the substrate through at least a third calendering roll gap, preferably also through at least a fourth calendering roll gap, particularly preferably also through at least a fifth calendering roll gap, and especially through at least a sixth calendering roll gap, each of which is formed by two rolls. At least one third calendering roll gap, at least one fourth calendering roll gap, at least one fifth calendering roll gap, and at least one sixth calendering roll gap may each be formed by two of these rolls, which rotate at different circumferential speeds in opposite directions of rotation. Optionally, the two rolls may be arranged linearly adjacent to each other or at an angle to each other. The advantage of an angled arrangement is that the components for film formation and lamination are decoupled. In addition, the radii of the two rolls may have different dimensions, which has the advantage of allowing higher pressure to be applied to the calendering roll gap (applied by the roll with the larger radius). Specifically, the system control unit is configured to set the calendering roll gap width between the two rolls respectively, and / or set the contact pressure in the calendering roll gap between the two rolls respectively.

[0123] Furthermore, the system can be configured to convey dry film with or without a substrate through at least a third calendering roll gap, preferably also through at least a fourth calendering roll gap, particularly preferably also through at least a fifth calendering roll gap, and especially through at least a sixth calendering roll gap, each of which is formed by two rolls. At least one third calendering roll gap, at least one fourth calendering roll gap, at least one fifth calendering roll gap, and at least one sixth calendering roll gap can each be formed by two of these rolls respectively, the two rolls rotating in opposite directions at different circumferential speeds. The dry film can be transferred onto the substrate in the third, fourth, fifth, or sixth roll gap.

[0124] Furthermore, the system can be configured to: due to the increase in circumferential speed, transfer a substrate-free dry film through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, and especially at least a sixth calendering roll gap.

[0125] Furthermore, the roll arrangement can be configured such that two dry films are prepared simultaneously in two first calendering roll gaps. Both dry films can be transferred to the third calendering roll gap, the fourth calendering roll gap, the fifth calendering roll gap, or the sixth calendering roll gap and / or transferred to the corresponding substrate. This allows for simultaneous coating on both sides or multilayer coating.

[0126] The device can also be configured to remove the dry film from a substrate to which the device has applied the dry film. The control unit of the system can be configured to initiate the removal of the dry film from the substrate. In this case, the system can also prepare a self-supporting dry film from the dry film laminated on the substrate.

[0127] In a preferred embodiment, the system is configured to perform the method according to the invention. Therefore, the system may have at least one feature or at least one configuration necessary for performing the method according to the invention.

[0128] According to the invention, a dry film is also provided, which is arranged as at least one web, preferably a plurality of parallel webs, on a substrate, wherein the at least one web, preferably a plurality of parallel webs, is defined by two boundary lines in the longitudinal direction of one or more webs, characterized in that the boundary lines are substantially straight and substantially parallel to each other. "Substantially straight and substantially parallel to each other" can be understood as the distance between the corresponding two boundary lines in the longitudinal direction varying less than or equal to 1000 μm, preferably less than or equal to 500 μm, particularly preferably less than or equal to 200 μm.

[0129] The length of each of the at least one web, preferably a plurality of parallel webs, in the longitudinal direction of one or more webs may be at least 0.05 m, preferably at least 0.5 m, particularly preferably at least 1 m, most preferably at least 5 m, and especially at least 10 m.

[0130] Furthermore, the width of at least one strip, preferably each of a plurality of parallel strips, perpendicular to the longitudinal direction of one or more strips, can be at least 200 mm and / or a maximum of 6000 mm, preferably 250 mm to 1300 mm, and particularly preferably 550 to 1250 mm. In a particular embodiment, the width of at least one strip, preferably each of a plurality of parallel strips, perpendicular to the longitudinal direction of one or more strips, can be at least 1 mm and at most 50 mm.

[0131] In a preferred embodiment, the dry film is arranged on the substrate as at least two parallel strips, preferably at least three parallel strips, particularly preferably at least four parallel strips, and especially at least five parallel strips.

[0132] The substrate on which the dry film is arranged can have a three-dimensional structure or be composed of a three-dimensional structure, the substrate preferably comprising woven fabric, non-woven fabric and / or stretched mesh or composed of woven fabric, non-woven fabric and / or stretched mesh.

[0133] Furthermore, the substrate may have a texture, preferably prepared by etching, sandblasting, and / or laser processing, the texture being particularly present on the surface of the substrate facing the dry film.

[0134] In addition, the substrate may include or consist of a porous layer, wherein the porous layer preferably includes or consists of an electrode layer and / or a granular layer. The layer applied to the substrate may have been applied to the substrate using a slurry process or a dry film process.

[0135] The substrate on which the dry film is disposed is preferably arranged to include or consist of a conductive material, wherein the conductive material is preferably selected from metals, carbon, and combinations thereof. The term "metal" also includes metal alloys.

[0136] An undercoat may be disposed in at least some areas between the dry film and the substrate, the undercoat contacting both the dry film and the substrate.The base coating may include a polymer (or binder) and a conductive material or be composed of a polymer (or binder) and a conductive material. The thickness of the base coating is preferably less than 10 μm, particularly preferably less than 2 μm. Preferably, the base coating is arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller. The advantage of the base coating is that it increases the adhesion between the dry film and the substrate region where the base coating is disposed. Therefore, the base coating can further improve the edge precision of the prepared dry film.

[0137] The dry film may include or be composed of the active material of the battery electrode. The mass fraction of the active material included in the dry film relative to the total mass of the dry film may be greater than 50 wt.%, preferably greater than 70 wt.%, particularly preferably greater than 90 wt.%. The active material is preferably selected from the active materials for the battery cathode and the active materials for the battery anode. The battery is preferably a lithium-ion or sodium-ion battery. The active material for the dry film cathode may be selected from lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NMC), nickel-rich lithium nickel manganese cobalt oxide (NMC 622, NMC 811 or related NMC materials), lithium nickel cobalt aluminum oxide (NCA), lithium cobalt oxide (LCO), lithium manganese nickel oxide (LMNO), high-pressure spinel (HVS), carbon, sulfur and combinations thereof. The active material for the dry film anode may be selected from graphite, hard carbon, silicon, carbon, tin, silicon oxide, lithium, lithium indium titanate (LTO) and combinations thereof. In addition, the dry film may include sodium-containing compounds based on metal oxides, polyanions (vanadates and / or phosphates) and Berlin blue analogues.

[0138] In addition, the dry film may include conductive additives, wherein the conductive additives are preferably selected from carbon nanotubes, carbon particles (e.g., carbon black, carbon nanofibers and / or carbon fibers), graphite, graphene, porous carbon (e.g., activated carbon) and combinations thereof. The proportion of conductive additives included in the dry film relative to the total mass of the dry film can be 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 1 wt.% to 4 wt.%.

[0139] In addition, the dry film (as an adhesive or a component of an adhesive) may include a non-fibrillated material exhibiting an adhesive effect, wherein the material is preferably selected from fluoropolymers (preferably polyvinylidene fluoride PVDF, ethylene-tetrafluoroethylene copolymer ETFE, polytetrafluoroethylene PTFE), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), biopolymers, polyolefins (e.g., polyethylene, preferably polyethylene with a molecular weight greater than 1,000,000 g / mol), polypeptides (e.g., sericin), polyamides, polyacrylates, and mixtures thereof.The proportion of this material included in the dry film relative to the total mass of the dry film can be 0.1 wt.% to 10 wt.%, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 0.5 wt.% to 1 wt.%.

[0140] In particular, the dry film (as an adhesive or a component of an adhesive) may include fibrillating materials (or fibrils) exhibiting an adhesive effect, wherein the material is preferably selected from fibrillating peptides (e.g., sericin), fibrillating plastics (e.g., fluoropolymers, such as PTFE, and / or polyolefins with a molecular weight greater than 1,000,000 g / mol, such as polyethylene with a molecular weight greater than 1,000,000 g / mol) and mixtures and combinations thereof. For example, the dry film may include fibrillable PTFE with a molecular weight greater than 106 g / mol, preferably greater than 107 g / mol. The fibrillating material increases the mechanical stability of the dry film because it forms a stable fibril network. The dry film may have anisotropically aligned fibrils. The terms "fibrillated material" or "fibril" are specifically understood to mean a thread-like structure, preferably with a diameter of 0.001 μm to 1 μm and / or a length of 1 μm to 100 μm. The fibrillated material or fibril may be isotropically distributed in the dry film. The mass fraction of the fibrillated material or fibril included in the dry film relative to the total mass of the dry film may be less than or equal to 10 wt.%, preferably less than or equal to 5 wt.%, particularly preferably less than or equal to 2 wt.%, most preferably 0.3 wt.% to 2 wt.%, and optionally 1 wt.% to 2 wt.%. The fibrillated material or fibril may be anisotropically distributed in the dry film.

[0141] Furthermore, the dry film may include an ion-conducting material, preferably an ion-conducting solid (solid electrolyte). The ion-conducting material is preferably selected from ion-conducting solids, gel-like ion conductors, salt-like ion conductors, and mixtures thereof. The ion-conducting solid is particularly preferably selected from sulfide solid ion conductors (e.g., lithium thiophosphate, LPS, argentite, LPSCl and / or LGPS, or sodium analogs), glassy solid ion conductors (e.g., LiAlSiO4 or NaAlSiO4), polymer solid ion conductors (e.g., PEO), ceramic solid ion conductors (e.g., LLZO, Lisocon and / or Nasicon, or corresponding sodium ion-conducting ceramic solid ion conductors) and mixtures thereof. The proportion of the solid electrolyte in the dry film relative to the total mass of the dry film can be 1 wt.%–99 wt.%, preferably 5 wt.%–30 wt.%, and particularly preferably 10 wt.%–20 wt.%.

[0142] The thickness of the dry film (i.e., in the direction perpendicular to the maximum surface area of ​​the dry film) can be from 5 μm to 500 μm, preferably from 10 μm to 150 μm, particularly preferably from 30 μm to 100 μm, and more preferably from 40 μm to 70 μm.

[0143] The liquid content of the dry film relative to the total volume of the dry film can be less than or equal to 1 vol.%.

[0144] By means of the method according to the invention, the porosity of the dry film can be 15%-80%, preferably 20%-50%, and particularly preferably 25%-35%. By subsequent compaction, the porosity of the dry film can be 0.1%-25%, preferably 0.1%-10%, and particularly preferably 0.1%-5%.

[0145] By means of the method according to the invention, the dry film can have a wavy pattern extending in the longitudinal direction of one or more strips of the dry film and extending perpendicular to the longitudinal direction (i.e., in the transverse direction) between substantially straight and substantially parallel boundary lines of one or more (corresponding) strips of the dry film, wherein preferably, the waves of the wavy pattern have a periodic spacing greater than 0 mm and less than 10 mm, preferably greater than 0 mm and less than 5 mm, in the transverse direction of one or more (corresponding) strips. Such a wavy pattern can be produced by different circumferential speeds. The periodic spacing of the wavy pattern can depend on the absolute circumferential speeds of the carrier roller and the pressure roller and the roll gap used. This correlation arises in conjunction with the rheological properties of the dry mixture used. In the case of a large difference in circumferential speed, the pattern may be more pronounced and the individual strips may be more spaced apart compared to the case of a small difference in circumferential speed.

[0146] The dry film can be prepared by means of the method according to the invention. Thus, the dry film can have at least one characteristic that necessarily arises from performing the method according to the invention.

[0147] According to the present invention, a battery is also provided, comprising:

[0148] a) an electrode comprising or composed of a dry film according to the present invention;

[0149] b) a counter electrode; and

[0150] c) an electrolyte disposed between the electrode and the counter electrode, preferably a liquid electrolyte or a solid electrolyte.

[0151] The subject method according to the present invention will be explained in more detail based on the following figures, but is not intended to limit it to the specific embodiments shown herein.

[0152] FIG1 illustrates an embodiment of a method or system for preparing a dry film according to the present invention. The upper figure is viewed along the axis of rotation TR of the carrier roller 3 and the counter roller 4 in the viewing direction, and the lower figure is viewed along the direction perpendicular to the axis of rotation TR of the carrier roller on the side where the processing devices 7, 8, 15 and 16 are arranged.The dry powder mixture is fed into a first calendering roll gap 2 formed by a carrier roller 3 and a first pair of pressure rollers 4. The carrier roller 3 rotates about its rotation axis TR at a first circumferential speed in a first rotation direction 5, and the pressure rollers 4 rotate about their rotation axis GR at a second circumferential speed lower than the first circumferential speed in a second rotation direction 6, wherein the second rotation direction 6 is opposite to the first rotation direction 5. The dry powder mixture passes through the first calendering roll gap 2 in a conveying direction, forming a dry film at least partially supported on the carrier roller 3. At least one first processing device 7 is arranged opposite to a first outer section 9 of the carrier roller 3 in a direction perpendicular to the carrier roller rotation axis TR; and at least one second processing device 8 is arranged opposite to a second outer section 10 of the carrier roller 3 in a direction perpendicular to the carrier roller rotation axis TR. The carrier roller 3 has an inner section 11 located between the first outer section 9 and the second outer section 10 in a direction parallel to the carrier roller rotation axis TR. The first processing apparatus 7 and the second processing apparatus 8 are each adapted to remove at least the area on the outer sections 9, 10 of the carrier roller 3 mounted on the carrier roller 3 by cutting. To laminate the dry film onto the substrate, the dry film is guided through a second calendering roll gap 17 formed by the third roller and the carrier roller 3. Due to the symmetrical arrangement of the first carrier roller 3 and the counterweight roller 4 pair with the second carrier roller 3 and the counterweight roller 4 pair in the embodiment shown in FIG. 1, the third roller in the first pair is formed here by the carrier roller in the second pair, and the third roller in the second pair is formed by the carrier roller in the first pair. In the second calendering roll gap 17, the dry film can be laminated / transferred onto a substrate (not shown), which passes through the second calendering roll gap 17 together with the dry film. Due to the symmetrical arrangement of the two pairs of carrier rollers 3 and counterweight rollers 4, the substrate can be laminated with dry film on both sides (double-sided lamination). In the illustrated embodiment, the carrier roller 3 also has two additional processing devices 15 and 16, each arranged opposite the middle region 14 of the inner section 11 in a direction perpendicular to the rotation axis TR of the carrier roller. These two processing devices can divide the dry film into two separate dry film strips or dry film belts.

[0153] FIG2 shows another embodiment of the method or system for preparing a dry film according to the present invention, which is substantially the same as the embodiment shown in FIG1. ​​The top view is taken along the rotation axis of the carrier roller in the direction of observation of the carrier roller 3 and the pressure roller 4; the middle view is taken on the side where the processing devices 7, 8, 15, and 16 are arranged in the direction perpendicular to the rotation axis TR of the carrier roller; and the bottom view is taken on the side where the dry powder mixture 1 is fed into the first calendering roll gap 2 in the direction perpendicular to the rotation axis TR of the carrier roller.The difference from the embodiment of FIG1 is that the second calendering roll gap 17 is not formed by the carrier roll 3 in the first roll pair and the carrier roll 3 in the second roll pair, but by the corresponding carrier roll 3 and, in each case, a third roll 19 or a second pair of pressure rolls, which rotates about its second pair of pressure rolls axis of rotation line 2GR in a third rotation direction 20 opposite to the first rotation direction 5. Due to the symmetrical arrangement, the corresponding third roll 19 forms a third calendering roll gap 18 in which the dry film can be laminated onto a substrate (not shown). The advantage of using two third rolls 19 is that the dry film undergoes additional compaction and extrusion in the second calendering roll gap 17 before being laminated onto the substrate in the third calendering roll gap 18, which can make the dry film more mechanically stable.

[0154] FIG3 shows another embodiment of the method or system for preparing a dry film according to the invention, which is substantially the same as the embodiment shown in FIG1. The top image is viewed along the axis of rotation of the carrier roller 3 in the direction of observation between the carrier roller 3 and the pressure roller 4. The bottom image is viewed along the line TR perpendicular to the axis of rotation of the carrier roller on the side where the processing devices 7 and 8 are arranged. The difference from the embodiments of Figures 1 and 2 is the absence of additional processing devices 15 and 16, therefore the dry film cannot be divided into two separate dry film strips or dry film strips; that is, only a single dry film strip or a single dry film strip is prepared. Another difference is that the carrier roller 3 has a first surface quality 12 in its inner section that allows the dry film to adhere to it, and a second surface quality 13 in its first and second outer sections that prevents the dry film from adhering to them. The second surface quality is designed here as a smooth surface of the carrier roller, the center roughness value Ra of which is less than or equal to 50% of the center roughness value of the carrier roller in its inner section. The advantage of this embodiment is that it prevents the dry film from adhering to segments of the carrier roller 3 that should not adhere from the outset. The dry film not adhering to these segments of the carrier roller 3 can be fed back to the first calendering roll gap 2 (as a dry powder mixture), which makes the process more efficient and also shortens the maintenance intervals of the processing equipment 7, 8.

[0155] FIG4 shows the carrier roller 3 and a portion of the processing equipment in the embodiment of FIG3 along a direction perpendicular to the axis of rotation TR of the carrier roller. The carrier roller 3 has a second surface quality 13 in the first outer segment and the second outer segment, which prevents the dry film 3 from adhering to the first outer segment and the second outer segment. The advantage of this is that the cutting unit 23 (here, an air nozzle) can cut the dry film more easily and with less energy consumption (i.e., with a lower airflow intensity), and the removal unit 24 (here, a suction device) can remove the cut dry film residue from the carrier roller 3 more easily and with less energy consumption (i.e., with a lower suction flow intensity).

[0156] FIG5 shows another embodiment of the method or system for preparing a dry film according to the invention, which is substantially the same as the embodiment shown in FIG1.The top view is taken along the axis of rotation of the carrier roller towards the carrier roller 3 and the counterweight roller 4, while the bottom view is taken towards the side where the processing devices 7 and 8 are arranged. One difference from the embodiment shown in Figure 1 is the absence of the additional processing devices 15 and 16. Another difference is that the first outer section 25 and the second outer section 26 of the counterweight roller 4 have a surface quality to which the dry film will not adhere. The first outer section 25 of the counterweight roller is arranged opposite the first outer section of the carrier roller 3 in a direction perpendicular to the axis of rotation TR of the carrier roller, and the second outer section 26 of the counterweight roller is arranged opposite the second outer section of the carrier roller 3 in a direction perpendicular to the axis of rotation TR of the carrier roller. Here, the surface quality of the first outer section 25 and / or the second outer section 26 of the counterweight roller 4 is configured as a concave surface of the counterweight roller 4, wherein the radius of this concave surface is preferably less than or equal to 99.9% of the radius of the counterweight roller 4 in the first region 27 of the inner section of the counterweight roller 4. The advantage of this embodiment is that, from the very beginning of the specification (pages 20 / 22, 29 CN 121152689 A), the dry film is prevented from adhering to the segments of the carrier roller 3 that should not adhere. The dry film not adhering to these segments of the carrier roller 3 can be fed back to the first calendering roll gap 2 (as a dry powder mixture), which makes the process more efficient and also shortens the maintenance intervals of the processing equipment 7, 8. In the illustrated embodiment, the carrier roller also has a second region 28 of the inner section, the shape of which is similar to the first and / or second outer sections of the carrier roller, i.e., it has a concave surface with a radius less than or equal to 99.9% of the radius of the pressure roller 4 in the first region 27 of the inner section of the pressure roller 4. This allows the dry film to be divided into two separate dry film strips or dry film strips, i.e., two parallel dry film strips or dry film tapes can be prepared.

[0157] FIG6 shows another embodiment of the method or system for preparing a dry film according to the invention, which is substantially the same as the embodiment shown in FIG2. This figure is viewed along the axis of rotation of the carrier roller in the direction of the carrier roller 3, the counter-pressure roller 4, and the second pair of pressure rollers 19. One difference from the embodiment shown in FIG2 is that the second pair of pressure rollers 19 are arranged at an angle to each other. The advantage of this is that the components used for film formation and lamination are decoupled.

[0158] FIG7 shows another embodiment of a method or system for preparing a dry film according to the invention. This figure shows the carrier roller 3, the counter-pressure roller 4, the second pair of pressure rollers 19, the third pair of pressure rollers 29, and the fourth pair of pressure rollers 30 along the axis of rotation of the carrier roller. In this embodiment, the radii of the second counter-pressure rollers 19 and the third counter-pressure rollers 29 are larger than the radii of the carrier roller 3 and the fourth pair of pressure rollers 30, which has the advantage of allowing higher pressure to be applied to the second calendering roll gap 17 and the fourth calendering roll gap 33.

[0159] FIG8 shows a photographic image of a dry film strip according to the invention, which has a wavy pattern.The wavy pattern extends in the longitudinal direction of the dry film strip (from left to right in FIG. 8) and perpendicular to the longitudinal direction of the dry film strip between substantially straight and substantially parallel boundary lines (from top to bottom in FIG. 8, i.e., in the transverse direction of the strip), wherein the waves of the wavy pattern have a periodic spacing of about 3 mm in the transverse direction of the strip.

[0160] FIG. 9 shows a schematic top view of a portion of the dry film according to the invention, which is formed in two segments on a current collector foil. The grid area represents the substrate (current collector foil), and the diagonally shaded area represents the coating (dry film). The interruptions shown above and below (white) indicate that this is a portion of a longer strip, i.e., a strip extending in the direction from the upper part to the lower part (or the opposite direction) in FIG. 9.

[0161] List of reference numerals

[0162] 1: Dry powder mixture;

[0163] 2: First calendering roll gap;

[0164] 3: Carrier roll;

[0165] 4: Counterroller;

[0166] 5: First rotation direction;

[0167] 6: Second rotation direction;

[0168] 7: First processing equipment (with cutting unit and removal unit);

[0169] 8: Second processing equipment (with cutting unit and removal unit);

[0170] 9: First outer section of carrier roll;

[0171] 10: Second outer section of carrier roll;

[0172] 11: Inner section of carrier roll;

[0173] 12: First surface quality of carrier roll (adhered to dry film);

[0174] 13: Second surface quality of carrier roll (not adhered to dry film);

[0175] 14: Middle region in the inner section of carrier roll;

[0176] 15: Additional processing equipment (with cutting unit and removal unit);

[0177] 16: Additional processing equipment (with cutting unit and removal unit); Specification 21 / 22 pages 30 CN 121152689 A

[0178] 17: Second calendering roll gap;

[0179] 18: Third calendering roll gap;

[0180] 19: Third roll (or second pair of pressure rolls);

[0181] 20: Third rotation direction (rotation direction of the third roll);

[0182] 21: (first) strip of dry film;

[0183] 22: Second strip of dry film;

[0184] 23: Cutting unit (e.g., air nozzle);

[0185] 24: Removal unit (e.g., suction device);

[0186] 25: First outer section of small radius pair of pressure rolls;

[0187] 26: Second outer section of the small radius pressure roller;

[0188] 27: First region of the inner section of the large radius pressure roller;

[0189] 28: Second region of the inner section of the small radius pressure roller;

[0190] 29: Fourth roller (or third pair of pressure rollers);

[0191] 30: Fifth roller (or fourth pair of pressure rollers);

[0192] 31: Fourth rotation direction (rotation direction of the fourth roller);

[0193] 32: Fifth rotation direction (rotation direction of the fifth roller);

[0194] 33: Fourth calendering roll gap;

[0195] 34: Fifth calendering roll gap;

[0196] TR: Rotation axis of the carrier roller;

[0197] GR: Rotation axis of the pressure roller;

[0198] 2GR: Rotation axis of the second pair of pressure rollers (e.g., rotation axis of the second carrier roller);

[0199] 3GR: Rotation axis of the third pair of pressure rollers (e.g., rotation axis of the third pair of pressure rollers);

[0200] 4GR: Rotation axis of the fourth pair of pressure rollers (e.g., rotation axis of the fourth pair of pressure rollers).Instruction manual, page 22 / 22, 31 CN 121152689 A, Figure 1; Instruction manual, Figure 1 / 8, page 32 CN 121152689 A, Figure 2; Instruction manual, Figure 2 / 8, page 33 CN 121152689 A, Figure 3; Instruction manual, Figure 3 / 8, page 34 CN 121152689 A, Figure 4; Instruction manual, Figure 4 / 8, page 35 CN 121152689 A, Figure 5; Instruction manual, Figure 5 / 8, page 36 CN 121152689 A, Figure 6; Instruction manual, Figure 6 / 8, page 37 CN 121152689 A, Figure 7; Instruction manual, Figure 7 / 8, page 38 CN 121152689 A, Figure 8; Figure 9; Instruction manual, Figure 8 / 8, page 39 CN 121152689 A.

Claims

1. A method for preparing a dry film, comprising feeding a dry powder mixture and / or a dry mixture into a first calendering roll gap formed by a carrier roll and a first pair of pressure rolls, wherein, The carrier roller rotates about its axis of rotation at a first circumferential speed in a first rotational direction, and the counter-pressure roller rotates about its axis of rotation at a second circumferential speed lower than the first circumferential speed in a second rotational direction, wherein the second rotational direction is opposite to the first rotational direction, wherein the dry powder mixture and / or the dry mixture passes through the first calendering roll gap in the conveying direction, wherein a dry film is formed that is supported on the carrier roller in at least some areas. The invention is characterized by using at least one first processing device, which is arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller; and using at least one second processing device, which is arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the axis of rotation of the carrier roller, wherein the carrier roller has an inner section located between the first outer section and the second outer section in a direction parallel to the axis of rotation of the carrier roller, wherein the first processing device and the second processing device are each adapted to remove the region of the dry film supported on the carrier roller and located at the outer section of the carrier roller.

2. The method according to the preceding claim, characterized in that, The dry film is laminated onto a substrate during the method, wherein the substrate preferably has at least some regions an undercoat, three-dimensional structure, texture, and / or porous layer for enhancing the adhesion of the dry film, wherein, particularly preferably, i) The base coating comprises or is composed of a polymer and a conductive material. The thickness of the base coating is less than 10 μm, preferably less than 2 μm, and / or the base coating is arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller; and / or ii) The substrate comprises woven fabrics, nonwoven fabrics, and / or stretched meshes as three-dimensional structures, or is composed of woven fabrics, nonwoven fabrics, and / or stretched meshes as three-dimensional structures; and / or iii) The texture is prepared by etching, sandblasting, and / or laser processing, wherein, The texture is particularly present on the surface of the substrate facing the dry film; and / or iv) The porous layer includes an electrode layer and / or a particle layer or is composed of an electrode layer and / or a particle layer.

3. The method according to any one of the preceding claims, characterized in that, The inner section of the carrier roller has, in at least some areas, a surface quality to which dry film adheres, wherein, i) The first outer section and / or the second outer section of the carrier roller have a surface quality to which the dry film will not adhere, wherein the surface quality is preferably configured as a smooth surface of the carrier roller, wherein the center roughness value Ra of the smooth surface is preferably less than or equal to 50% of the center roughness value of the carrier roller in the inner section, wherein the center roughness value Ra of the smooth surface is particularly preferably 0.005 μm to 1 μm; and / or ii) The first outer section and / or the second outer section of the pressure roller have a surface quality to which dry film will not adhere, the first outer section of the pressure roller is arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, and the second outer section of the pressure roller is arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, wherein the surface quality of the first outer section and / or the second outer section of the pressure roller is preferably: a) A concave surface is formed in the counterweight roller, wherein the radius of the concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, and especially less than or equal to 90%, of the radius of the counterweight roller in the first region of the inner section of the counterweight roller; and / or b) A coating formed on the first outer section and / or the second outer section of the pressure roller, preferably a coating comprising DLC ​​and / or PTFE or composed of DLC and / or PTFE, such that the dry film adhesion on the pressure roller is at least 1 wt.%, particularly at least 10 wt.%, less than that on the inner section of the pressure roller, and preferably has no adhesion on the pressure roller, wherein the inner section of the pressure roller optionally has a coating and / or texture to which the dry film adheres, wherein the coating particularly preferably comprises or is composed of materials selected from or composed of materials selected from: PTFE, DLC, tungsten carbide, hard chrome, and combinations thereof. The carrier roller may optionally have at least one second region of the inner section, the at least one second region being configured to resemble the first outer section and / or the second outer section of the carrier roller.

4. The method according to any one of the preceding claims, characterized in that, The first processing device and the second processing device each: i) Includes a cutting unit for separating a region of the dry film at a corresponding outer segment of the carrier roller supported on the carrier roller from a region of the dry film at a corresponding inner segment of the carrier roller supported on the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof; and / or ii) Includes a removal unit for removing the region of the dry film supported on the carrier roller and located at a corresponding outer section of the carrier roller, wherein the removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof; and / or iii) It has an additional removal unit for removing the area of ​​the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction.

5. The method according to any one of the preceding claims, characterized in that, The inner section of the carrier roller is divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and an intermediate region is arranged between each of the two adjacent inner section regions. The boundaries of the intermediate regions are defined by two opposing boundary lines from the 2n boundary lines in the direction of the carrier roller's rotation axis. i) The at least two inner segment regions have a surface quality to which dry film adheres, and the intermediate regions preferably each have a surface quality to which dry film does not adhere; and / or ii) In a direction perpendicular to the axis of rotation of the carrier roller, using additional processing equipment opposite to each intermediate region of the inner section, said additional processing equipment being adapted to remove, at least by cutting, a region of the dry film supported on the carrier roller and located in the intermediate region of the carrier roller, wherein each additional processing equipment is particularly preferably: The product includes a cutting unit for separating a region of the dry film at a corresponding intermediate region of the carrier roller supported on the carrier roller from a region of the dry film at an inner section of the carrier roller supported on the carrier roller by cutting. The cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof. The device includes a removal unit for removing the area of ​​the dry film supported on the carrier roller and located in a corresponding intermediate region of the carrier roller, wherein the removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof.

6. The method according to any one of claims 4 or 5, characterized in that, The removal unit is used, and optionally the additional removal unit is also used, to feed the area of ​​the dry film to be removed into the first calendering roll gap, optionally first... i) The removed area of ​​the dry film is fed into a dry mixture, which is processed into a dry powder mixture, which is then fed into a first calendering roll gap, wherein the processing into a dry powder mixture preferably includes processing selected from extruder processing, jet mill, pin mill, impact mill, mortar mill, roller mill, and combinations thereof; or ii) The removed area of ​​the dry film is fed into a dry mixture and / or a dry powder mixture, which is then fed into a first calendering roll gap, wherein the proportion of the removed area of ​​the fed dry film relative to the total proportion of the dry powder mixture and / or the dry mixture is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, and even more particularly preferably at least 10 wt.%.

7. The method according to any one of the preceding claims, characterized in that, First calendering roll gap i) The length is at least 300 mm, preferably at least 600 mm, particularly preferably at least 1200 mm, and optionally at most 3000 mm; and / or ii) having a mask and / or funnel arranged above the calender roll gap, wherein the mask preferably reduces the application of a certain amount of dry powder mixture and / or dry mixture to at least two opposite outer sections of the carrier roll, and optionally also to at least one intermediate region of the inner section of the carrier roll.

8. The method according to any one of the preceding claims, characterized in that, The carrier roller and / or counter-pressure roller a) Diameter less than or equal to 100 cm, optionally from 10 cm to 100 cm, particularly preferably less than or equal to 50 cm, optionally from 10 cm to 50 cm, particularly less than 30 cm; and / or b) In a direction perpendicular to the axis of the carrier roller and / or the pressure roller, the width is greater than 30 cm, preferably greater than 60 cm, particularly preferably greater than 100 cm, and especially a maximum of 300 cm.

9. The method according to any one of the preceding claims, characterized in that, Laminating a dry film onto a substrate includes the following steps: i) The dry film on the carrier roller is conveyed into a second calendering roll gap formed by the carrier roller and the second pair of pressure rollers, wherein the second pair of pressure rollers rotates about the axis of rotation of the second pair of pressure rollers in a third rotational direction at a second circumferential speed greater than or equal to the first circumferential speed of the carrier roller, wherein... The third rotation direction is opposite to the first rotation direction; ii) Optionally, the dry film is also conveyed together with the substrate through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, and especially at least a sixth calendering roll gap; iii) Optionally, due to the increase in circumferential speed, the substrate-free dry film is conveyed by transfer through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, and especially at least a sixth calendering roll gap; Among them, a substrate with a dry film laminated on it is produced.

10. A system for preparing a dry film, comprising: a) An apparatus configured to prepare a dry film from a dry powder mixture and / or a dry mixture, wherein the apparatus includes a carrier roller and a first pair of pressure rollers, wherein the carrier roller and the pair of pressure rollers form a first calendering roll gap to supply the dry powder mixture and / or the dry mixture, wherein the carrier roller is adapted to rotate about a carrier roller rotation axis, and the pair of pressure rollers is adapted to rotate about a pair of pressure roller rotation axes; b) A control unit configured at least to rotate the carrier roller about its carrier roller rotation axis at a first circumferential speed in a first rotation direction, and to rotate the counter-pressure roller about its counter-pressure roller rotation axis at a second circumferential speed lower than the first circumferential speed in a second rotation direction, wherein the second rotation direction is opposite to the first rotation direction, wherein the control unit is specifically configured to set the roll gap width and / or the contact pressure in the calendering roll gap between the carrier roller and the first counter-pressure roller; The system is characterized in that it has at least one first processing device and at least one second processing device, the at least one first processing device being arranged opposite to a first outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, and the at least one second processing device being arranged opposite to a second outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, wherein the carrier roller has an inner section located between the first outer section and the second outer section in a direction parallel to the rotation axis of the carrier roller, and wherein the first processing device and the second processing device are each adapted to remove, at least by cutting, the region of the dry film supported on the carrier roller and located at the outer section of the carrier roller.

11. The system according to claim 10, characterized in that, The system includes a substrate and is configured to laminate the dry film onto the substrate, wherein the substrate preferably has, in at least some regions, an undercoat, a three-dimensional structure, a texture, and / or a porous layer for enhancing the adhesion of the dry film, wherein particularly preferred i) The base coating comprises or is composed of a polymer and a conductive material. The thickness of the base coating is less than 10 μm, preferably less than 2 μm, and / or the base coating is arranged on the substrate in a region opposite the inner section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller; and / or ii) The substrate comprises woven fabrics, nonwoven fabrics, and / or stretched meshes as three-dimensional structures, or is composed of woven fabrics, nonwoven fabrics, and / or stretched meshes as three-dimensional structures; and / or iii) The texture is prepared by etching, sandblasting, and / or laser processing; and / or iv) The porous layer includes an electrode layer and / or a particle layer or is composed of an electrode layer and / or a particle layer.

12. The system according to any one of claims 10 or 11, characterized in that, The inner section of the carrier roller has a first surface quality to which the dry film adheres in at least some areas, wherein, i) The first outer section and / or the second outer section of the carrier roller have a second surface quality to which the dry film will not adhere, wherein this surface quality is preferably designed as a smooth surface of the carrier roller, wherein the center roughness value Ra of the smooth surface is preferably less than or equal to 50% of the center roughness value of the carrier roller in the inner section, wherein the center roughness value Ra of the smooth surface is particularly preferably 0.001 μm to 1 μm; and / or iii) The first outer section and / or the second outer section of the pressure roller have a surface quality to which dry film will not adhere, the first outer section of the pressure roller is arranged opposite to the first outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, and the second outer section of the pressure roller is arranged opposite to the second outer section of the carrier roller in a direction perpendicular to the rotation axis of the carrier roller, wherein the surface quality of the first outer section and / or the second outer section of the pressure roller is preferably: a) A concave surface is formed in the counterweight roller, wherein the radius of the concave surface is preferably less than or equal to 99.9%, preferably less than or equal to 99%, particularly preferably less than or equal to 95%, and especially less than or equal to 90%, of the radius of the counterweight roller in the first region of the inner section of the counterweight roller; and / or b) A coating formed on the first outer section and / or the second outer section of the pressure roller, preferably a coating comprising DLC ​​and / or PTFE or composed of DLC and / or PTFE, such that the dry film adhesion on the pressure roller is at least 1 wt.%, particularly at least 10 wt.%, less than that on the inner section of the pressure roller, and preferably has no adhesion on the pressure roller, wherein the inner section of the pressure roller optionally has a coating and / or texture to which the dry film adheres, wherein the coating particularly preferably comprises or is composed of materials selected from or composed of materials selected from: PTFE, DLC, tungsten carbide, hard chrome, and combinations thereof. The carrier roller may optionally have at least one second region of the inner section, the at least one second region being configured to resemble the first outer section and / or the second outer section of the carrier roller.

13. The system according to any one of claims 10 to 12, characterized in that, The first processing device and the second processing device each i) Includes a cutting unit configured to separate a region of the dry film at a corresponding outer segment of the carrier roller supported on the carrier roller from a region of the dry film at a corresponding inner segment of the carrier roller supported on the carrier roller by cutting, wherein the cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof; and / or ii) Includes a removal unit configured to remove the dry film from a region supported on the carrier roller and located at a corresponding outer segment of the carrier roller, wherein the removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof; and / or iii) It has an additional removal unit configured to remove a region of the dry film perpendicular to the coating direction to achieve intermittent coating in the coating direction.

14. The system according to any one of claims 10 to 13, characterized in that, The inner section of the carrier roller is divided into at least two inner section regions by at least 2n mutually parallel boundary lines spanning the circumference of the carrier roller, where n is an integer, and an intermediate region is arranged between each of the two adjacent inner section regions. The boundaries of the intermediate regions are defined by two opposing boundary lines from the 2n boundary lines in the direction of the rotation axis of the carrier roller. i) The at least two inner segment regions have a surface quality to which dry film adheres, and the intermediate regions preferably each have a surface quality to which dry film does not adhere; and / or ii) The system has additional processing equipment in a direction perpendicular to the rotation axis of the carrier roller, each opposite to a middle region of the inner section, the additional processing equipment being adapted to remove, at least by cutting, a region of the dry film supported on the carrier roller and located in the middle region of the carrier roller, wherein each additional processing equipment is particularly preferably: The product includes a cutting unit configured to separate a region of the dry film at a corresponding intermediate region of the carrier roller supported on the carrier roller from a region of the dry film at an inner section of the carrier roller supported on the carrier roller by cutting. The cutting unit is preferably selected from a rotary cutter, an air nozzle, a laser, or a combination thereof. The device includes a removal unit configured to remove the dry film from a region supported on the carrier roller and located in a corresponding intermediate region of the carrier roller, wherein the removal unit is preferably selected from air nozzles, scrapers, brushes, suction devices, and combinations thereof.

15. The system according to any one of claims 13 or 14, characterized in that, The removal unit is configured, and optionally, the additional removal unit is also configured, to feed the removed area of ​​the dry film into the first calendering roll gap, optionally first... The removed area of ​​the dry film is fed into a dry mixture to be processed into a dry powder mixture, wherein the processing equipment of the system is configured to process the dry mixture into a dry powder mixture and feed the dry powder mixture into a first calendering roll gap, wherein the processing equipment is preferably selected from an extruder, jet mill, pin mill, impact mill, mortar mill, roller mill, or combinations thereof; or First, the removed area of ​​the dry film is supplied to a dry powder mixture and / or a dry mixture, wherein the system is configured to supply the dry powder mixture and / or the dry mixture to a first calendering roll gap, wherein the percentage of the removed area of ​​the supplied dry film relative to the total percentage of the dry powder mixture and / or the dry mixture is preferably at least 0.1 wt.%, particularly preferably at least 1 wt.%, and more particularly preferably at least 10 wt.%.

16. The system according to any one of claims 10 to 15, characterized in that, First calender gap i) The length is at least 300 mm, preferably at least 600 mm, and particularly preferably at least 1200 mm; and / or ii) having a mask and / or funnel arranged above the calender roll gap, wherein the mask is preferably adapted to reduce the application of a certain amount of dry powder mixture and / or dry mixture to at least two opposite outer sections of the carrier roll, and optionally also to at least one intermediate region of the inner section of the carrier roll.

17. The system according to any one of claims 10 to 16, characterized in that, The carrier roller and / or counter-pressure roller a) Diameter less than or equal to 100 cm, optionally from 10 cm to 100 cm, particularly preferably less than or equal to 50 cm, optionally from 10 cm to 50 cm, particularly less than 30 cm; and / or b) In a direction perpendicular to the axis of the carrier roller and / or the pressure roller, the width is greater than 30 cm, preferably greater than 60 cm, particularly preferably greater than 100 cm, and especially a maximum of 300 cm.

18. The system according to any one of claims 10 to 17, characterized in that, The system i) including a second pair of pressure rollers forming a second calendering roll gap with the carrier roller, wherein the system is configured to convey dry film on the carrier roller into the second calendering roll gap, wherein the control unit is configured to cause the second pair of pressure rollers to rotate about the axis of rotation of the second pair of pressure rollers in a third rotational direction at a second circumferential speed greater than or equal to a first circumferential speed of the carrier roller, wherein the third rotational direction is opposite to the first rotational direction; ii) Optionally, it also includes at least one third roller, preferably at least one fourth roller, particularly preferably at least one fifth roller, more preferably at least one sixth roller, and especially at least one seventh roller; iii) Optionally, the dry film is configured to be conveyed together with the substrate through at least a third calendering roll gap, preferably also through at least a fourth calendering roll gap, particularly preferably also through at least a fifth calendering roll gap, and especially through at least a sixth calendering roll gap, each of which is formed by two rolls, wherein the two rolls are optionally arranged linearly or at an angle to each other and / or have different radii. Specifically, the control unit of the system is configured to set the roll gap width of the calendering roll gap between the two rolls, and / or set the contact pressure in the corresponding calendering roll gap between the two rolls; and / or iv) Optionally configured to: due to the increase in circumferential speed, transfer the substrate-free dry film through at least a third calendering roll gap, preferably at least a fourth calendering roll gap, particularly preferably at least a fifth calendering roll gap, especially at least a sixth calendering roll gap.

19. A dry film arranged as at least one strip, preferably a plurality of parallel strips, wherein, On the substrate, the at least one strip, preferably the plurality of parallel strips, is defined by two boundary lines in the longitudinal direction of one or more strips, characterized in that the boundary lines are substantially straight and substantially parallel to each other, wherein the distance between the corresponding two boundary lines varies in the longitudinal direction by less than or equal to 1000 μm, preferably less than or equal to 500 μm, and particularly preferably less than or equal to 200 μm.

20. The dry film according to claim 19, characterized in that, The at least one strip, preferably each of a plurality of parallel strips. i) The length in the longitudinal direction of one or more strips is at least 0.1 m, preferably at least 0.5 m, particularly preferably at least 1 m, more particularly preferably at least 5 m, especially at least 10 m; and / or ii) A width perpendicular to the longitudinal direction of one or more strips of at least 200 mm and / or a maximum of 1200 mm, preferably 250 mm to 650 mm, particularly preferably 250 mm to 350 mm; and / or iii) It has a wavy pattern that extends in the longitudinal direction of one or more strips of the dry film and extends perpendicular to the longitudinal direction of one or more strips between substantially straight and substantially parallel boundary lines of one or more strips of the dry film, wherein preferably, the waves of the wavy pattern have a periodic spacing of greater than 0 mm and less than 10 mm, preferably greater than 0 mm and less than 5 mm, in the transverse direction of one or more strips. The dry film may optionally be arranged on the substrate as at least two parallel strips, preferably at least three parallel strips, particularly preferably at least four parallel strips, and especially at least five parallel strips.

21. The dry film according to any one of claims 19 or 20, characterized in that, An undercoat is disposed in at least some areas between the dry film and the substrate, the undercoat contacting both the dry film and the substrate, wherein preferably... i) The base coating comprises or is composed of a polymer and a conductive material. And / or the thickness of the base coating is less than 10 μm, particularly preferably less than 2 μm; and / or ii) The substrate comprises or is composed of a three-dimensional structure, preferably comprising woven fabric, non-woven fabric, and / or stretched mesh, or is composed of woven fabric, non-woven fabric, and / or stretched mesh; and / or iii) The substrate has a texture, preferably prepared by etching, sandblasting, and / or laser processing, wherein the texture is particularly present on the surface of the substrate facing the dry film; and / or iv) The substrate comprises or is composed of a porous layer, wherein the porous layer preferably comprises or is composed of an electrode layer and / or a particle layer.

22. The dry film according to any one of claims 19 to 21, characterized in that, The dry film includes the active material of the battery electrode, wherein the active material preferably... i) Selected from active materials used for battery cathodes and active materials used for battery anodes, wherein, The active material is particularly preferably selected from lithium iron phosphate, lithium manganese iron phosphate, lithium manganese oxide, lithium nickel manganese cobalt oxide, nickel-rich lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminum oxide, lithium cobalt oxide, lithium manganese nickel oxide, high-pressure spinel, carbon, sulfur, graphite, hard carbon, silicon, tin, silicon oxide, lithium, lithium indium lithium titanate, sodium-containing compounds based on metal oxides, polyanions, Berlin blue analogues, and combinations thereof; and / or ii) The mass fraction of active material contained in the dry film relative to the total mass of the dry film is greater than 50 wt.%, preferably greater than 70 wt.%, and especially preferably greater than 90 wt.%; i) The liquid content in the dry film is less than or equal to 1 vol% relative to the total volume of the dry film.

23. The dry film according to any one of claims 19 to 22, characterized in that, The dry film includes a conductive additive, wherein the conductive additive is preferably... i) Selected from carbon nanotubes, carbon particles, graphite, graphene, porous carbon, and combinations thereof; and / or ii) The conductive additive contained in the dry film has a mass fraction of 0.1 wt.% to 10 wt.% relative to the total mass of the dry film, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 1 wt.% to 4 wt.%.

24. The dry film according to any one of claims 19 to 23, characterized in that, The dry film comprises a non-fibrillated material that produces an adhesion effect, wherein the material is preferably... i) Selected from fluoropolymers, carboxymethyl cellulose, styrene-butadiene rubber, biopolymers, polyolefins, polypeptides, polyamides, polyacrylates, and mixtures thereof; and / or; ii) The non-fibrillated material contained in the dry film has a mass fraction of 0.1 wt.% to 10 wt.% relative to the total mass of the dry film, preferably 0.5 wt.% to 5 wt.%, and particularly preferably 0.5 wt.% to 4 wt.%.

25. The dry film according to any one of claims 19 to 24, characterized in that, The dry film comprises a fibrillated material that produces an adhesion effect, wherein the fibrillated material is preferably... i) Selected from fibrillated polypeptides, fibrillated plastics, and mixtures and combinations thereof, wherein the fibrillated material is particularly preferred to have a molecular weight greater than 10. 6 g / mol, optimal value greater than 10 7 g / mol of fibrillable PTFE; and / or ii) The fibrillated material contained in the dry film has a mass fraction relative to the total mass of the dry film that is greater than 1 wt.%, preferably greater than 10 wt.%, and particularly preferably greater than 50 wt.%; and / or iii) Includes or is composed of fibrous structures, wherein the diameter of the fibrous structures is 0.001 μm to 1 μm and / or length from 1 μm to 100 μm; and / or iv) Isotropically distributed in the dry film; and / or v) is anisotropically distributed in the dry film.

26. The dry film according to any one of claims 19 to 25, characterized in that, The dry film includes an ion-conducting material, wherein the ion-conducting material is preferably... i) Selected from ion-conducting solids, gel-like ion conductors, salt-like ion conductors, and mixtures thereof. The ion-conducting solid is preferably selected from sulfide solid ion conductors, glassy solid ion conductors, polymer solid ion conductors, ceramic solid ion conductors, and mixtures thereof; and / or ii) The mass fraction of the ion-conducting material present in the dry film relative to the total mass of the dry film is from 1 wt.% to 99 wt.%, preferably from 5 wt.% to 30 wt.%, and particularly preferably from 10 wt.% to 20 wt.%.

27. The dry film according to any one of claims 19 to 26, characterized in that, The dry film i) The layer thickness is 5 μm to 500 μm, preferably 10 μm to 150 μm, particularly preferably 30 μm to 100 μm, and more preferably 40 μm to 70 μm; and / or ii) The liquid content in the dry film is less than or equal to 1 vol.% relative to the total volume of the dry film; and / or iii) Porosity of 15% to 80%, preferably 20% to 50%, particularly preferably 25% to 35%, or The porosity is 0.1% to 25%, preferably 0.1% to 10%, and particularly preferably 0.1% to 5%.

28. The dry film according to any one of claims 19 to 27, characterized in that, The dry film is prepared by the method according to any one of claims 1 to 9.

29. A battery, comprising: a) An electrode comprising or consisting of a dry film according to any one of claims 19 to 28; b) Counter electrode; as well as c) An electrolyte disposed between the electrode and the counter electrode, preferably a solid electrolyte.

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