A dry self-supporting film and current collector composite device

Abstract

The application relates to a dry self-supporting film and current collector composite device, which comprises, in the unwinding direction of the current collector, a current collector unwinding roller, a pretreatment unit, a self-supporting film supply unit, a composite unit and a winding unit; the pretreatment unit comprises a coating machine and a pre-solidification oven; the coating machine is used for coating the current collector, and the pre-solidification oven is used for solidifying the coated current collector; the self-supporting film supply unit comprises self-supporting modules arranged on the two sides of the current collector respectively; the self-supporting modules comprise, in the unwinding direction of the self-supporting film, a self-supporting unwinding roller and a multistage roller pressing module in sequence; the multistage roller pressing module comprises a plurality of parallelly arranged pre-pressing rollers, a pre-pressing gap is formed between the adjacent pre-pressing rollers, and the pre-pressing gap gradually decreases in the unwinding direction of the self-supporting film. The self-supporting film and current collector composite device improves the composite efficiency of the self-supporting film and the current collector, the stress is uniform when the self-supporting film and the current collector are composited, and the composite defects are reduced.

Description

Technical Field

[0001] This application relates to the field of dry electrode technology, and in particular to a dry self-supporting membrane and current collector composite device. Background Technology

[0002] In the fabrication process of commercial power battery electrodes, wet processes are commonly used. However, wet processes suffer from significant drawbacks, including high energy consumption, complex solvent handling, solvent safety risks, environmental unfriendliness, and cost constraints. To overcome these shortcomings, existing technologies have proposed a dry process where active materials, conductive agents, and binders are dry-mixed, directly calendered into a self-supporting film, and then combined with a current collector to form the electrode sheet.

[0003] Currently, in the dry process of electrode manufacturing, the efficient and high-quality composite of the self-supporting film and the current collector is an important factor affecting the performance and quality of the electrode. However, the existing technology still needs to be optimized for the efficient and high-quality composite of the self-supporting film and the current collector.

[0004] Therefore, there is a need for a dry self-supporting membrane and current collector composite device that can improve the efficiency and quality of self-supporting membrane and current collector composite. Utility Model Content

[0005] Therefore, it is necessary to provide a dry self-supporting membrane and current collector composite device, the specific technical solution of which is as follows.

[0006] A dry self-supporting film and current collector composite device includes a current collector unwinding roller, a pretreatment unit, a self-supporting film supply unit, a composite unit and a winding unit arranged sequentially along the unwinding direction of the current collector. The pretreatment unit includes a coating machine and a pre-curing oven; the coating machine is used to coat the current collector, and the pre-curing oven is used to cure the coated current collector. The self-supporting film supply unit includes self-supporting modules arranged on both sides of the current collector; the self-supporting module includes a self-supporting unwinding roller and a multi-stage rolling module in sequence along the unwinding direction of the self-supporting film; the multi-stage rolling module includes multiple pre-pressing rollers arranged in parallel, so that a pre-pressing gap is formed between adjacent pre-pressing rollers, and the pre-pressing gap gradually decreases along the unwinding direction of the self-supporting film.

[0007] Furthermore, the multi-stage roll pressing module includes four pre-pressing rollers arranged in parallel, and the four pre-pressing rollers sequentially form pre-pressing gaps of 0.5mm, 0.3mm and 0.1mm in size along the unwinding direction of the self-supporting film.

[0008] Furthermore, the preload roller adopts a convex curved surface design, and the roller crown of the preload roller is 0.05mm.

[0009] Furthermore, the pretreatment unit includes, in sequence along the unwinding direction of the current collector, a first microgravure coating machine, a first pre-curing oven, a first back roller, a second microgravure coating machine, and a second pre-curing oven; The first back roller changes the movement direction of the current collector from a first horizontal direction to a second horizontal direction, the first horizontal direction being opposite to the second horizontal direction, so that the first micro-gravure coating machine and the second micro-gravure coating machine coat both sides of the current collector respectively.

[0010] Furthermore, an ion cleaner is provided between the current collector unwinding roller and the coating machine. The ion cleaner includes a reaction chamber, a metering inlet device, and a molecular pump. The two ends of the reaction chamber are respectively provided with slots to accommodate the current collector passing through. Parallel electrodes are respectively provided on the upper and lower sides of the current collector in the reaction chamber. The metering inlet device is connected to the reaction chamber. The molecular pump is connected to the reaction chamber.

[0011] Furthermore, the groove is provided with a telescopic scraper, one side of which is in contact with the collector, and the other side is connected to the wall of the groove through a telescopic component.

[0012] Furthermore, the coating machine includes a glue tank, a ceramic anilox roller, a limiting roller, and a scraper; the ceramic anilox roller is rotatably mounted in the glue tank; the limiting roller is located above the ceramic anilox roller and forms a gap with the ceramic anilox roller to accommodate the flow of the current collector; the scraper is mounted on the glue tank and contacts the ceramic anilox roller.

[0013] Furthermore, the composite unit includes composite rollers respectively disposed on both sides of the current collector.

[0014] Furthermore, a second back roller is provided between the pretreatment unit and the self-supporting film supply unit, the second back roller adjusting the movement direction of the current collector from the horizontal direction to the vertical direction; a third back roller is provided at the beginning of the winding unit, the third back roller adjusting the movement direction of the current collector from the vertical direction to the horizontal direction.

[0015] Furthermore, the current collector unwinding unit also includes a first correction sensor and a first correction roller.

[0016] Beneficial effects: The dry self-supporting membrane and current collector composite device provided by this utility model integrates the coating equipment of the current collector and the composite equipment of the self-supporting membrane and the current collector into one, eliminating the need for additional transfer processes. Furthermore, self-supporting modules are set on both sides of the current collector to achieve simultaneous composite on both sides, improving the composite efficiency of the self-supporting membrane and the current collector. The multi-stage roller pressing module compacts the self-supporting membrane step by step with decreasing gaps, and the infrared pre-curing unit strengthens the structure, improving the density, flatness, and mechanical strength of the electrode sheet, ensuring uniform stress during composite with the current collector, reducing composite defects, and improving product consistency and reliability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is one of the schematic diagrams of the composite device; Figure 2 This is the second schematic diagram of the composite device; Figure 3 This is a schematic diagram of a planar module of the composite device; Figure 4 This is a schematic diagram of an ion cleaner; Figure 5 for Figure 4 Enlarged view of region A in the middle; Figure 6 This is a schematic diagram of the structure of the first micro-gravure coating machine; Figure 7 This is a cross-sectional view of the infrared activation box; Figure 8 This is a schematic diagram of a multi-stage roller pressing module.

[0019] Explanation of reference numerals in the attached drawings: 0, current collector unwinding roller; 1, pretreatment unit; 2, self-supporting film supply unit; 3, laminating unit; 4, winding unit; 11. First alignment sensor; 12. First alignment roller; 13. Ion cleaner; 14. First microgravure coating machine; 15. First pre-curing oven; 16. First back roller; 17. Second microgravure coating machine; 18. Second pre-curing oven; 19. Infrared activation box; 110. Second back roller; 131. Reaction chamber; 132. Telescopic scraper; 133. Metering inlet; 134. Molecular pump; 135. Parallel electrode; 141. Glue tank; 142. Ceramic anilox roller; 143. Scraper; 144. Limiting roller; 21. First self-supporting module; 22. Second self-supporting module; 211. Self-supporting unwinding roller; 212. Multi-stage roll pressing module; 213. First traction roller; 214. Infrared pre-curing unit; 215. Support roller; 216. Slitting device; 217. Second traction roller; 218. Pre-pressing roller; 219. Infrared radiator; 31. First composite roller; 32. Second composite roller; 41. Third back roller; 42. Fourth traction roller; 43. Second correction sensor; 44. Second correction roller; 45. Tension sensor; 46. Composite electrode take-up roller. Detailed Implementation

[0020] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0021] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0025] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0026] Example Reference Figure 1-3 As shown, this embodiment provides a dry self-supporting film and current collector composite device, including a current collector unwinding roller 0, a pretreatment unit 1, a self-supporting film supply unit 2, a composite unit 3, and a winding unit 4 arranged sequentially along the unwinding direction of the current collector. The pretreatment unit 1 includes a coating machine and a pre-curing oven; the coating machine is used to coat the current collector with an adhesive, and the pre-curing oven is used to dry and cure the adhesive on the surface of the coated current collector. It should be noted that the coating machine can be a microgravure coating machine, and the pre-curing oven can be any oven available in the prior art.

[0027] Specifically, the self-supporting film supply unit 2 includes self-supporting modules respectively arranged on both sides of the current collector; that is, the self-supporting module is divided into a first self-supporting module 21 and a second self-supporting module 22, which are located on both sides of the current collector. The self-supporting module, along the unwinding direction of the self-supporting film, sequentially includes a self-supporting unwinding roller 211 and a multi-stage rolling module 212. (Refer to...) Figure 8 As shown, the multi-stage roll pressing module 212 includes multiple pre-pressing rollers 218 arranged in parallel, so that a pre-pressing gap is formed between adjacent pre-pressing rollers 218, and the pre-pressing gap gradually decreases along the unwinding direction of the self-supporting film.

[0028] The current collector is unwound by the current collector unwinding roller 0, and then coated with adhesive by the coating machine, which facilitates the subsequent lamination of the current collector with the self-supporting film. After coating, the current collector is heated and cured by the hot air in the pre-curing oven. When the current collector passes through the self-supporting film supply unit 2, the self-supporting unwinding rollers 211 of the self-supporting modules on both sides unwind the self-supporting film respectively. Under the action of the lamination unit 3, the current collector is laminated with the self-supporting films on both sides respectively, and finally wound up by the winding unit 4. In the above process, the composite electrode winding roller 46 in the winding unit 4 can be driven by a motor to rotate, providing power for the movement of the current collector and the self-supporting film.

[0029] The dry self-supporting film and current collector composite device provided in this embodiment integrates the current collector coating equipment and the self-supporting film and current collector composite equipment into one, eliminating the need for additional transfer processes. Furthermore, self-supporting modules are set on both sides of the current collector for simultaneous composite on both sides, improving the composite efficiency of the self-supporting film and current collector. A multi-stage roller pressing module 212 is used to progressively compact the self-supporting film with decreasing gaps, and an infrared pre-curing unit 214 strengthens the structure, improving the density, flatness, and mechanical strength of the electrode sheet. This ensures uniform stress during composite with the current collector, reduces composite defects, and improves product consistency and reliability.

[0030] Specifically, refer to Figure 8 As shown, the multi-stage roll forming module 212 includes four parallel pre-pressing rollers 218. These four rollers form pre-pressing gaps of 0.5mm, 0.3mm, and 0.1mm respectively along the unwinding direction of the self-supporting film. The pre-pressing rollers 218 employ a convex curved surface design, with a roller crown of 0.05mm. As the self-supporting film passes through the pre-pressing rollers 218 with decreasing gaps, precision calendering is gradually achieved. The decreasing gap gradient ensures a gradual and controllable calendering process, effectively eliminating internal stress and improving uniformity. The convex curved surface design compensates for elastic deformation caused by pressure during roll forming, ensuring consistent calendering between the edges and the center area. Ultimately, this achieves precise thickness control and structural reinforcement of the self-supporting film, providing a uniform and stable material foundation for subsequent lamination.

[0031] Specifically, continue to refer to Figure 1-3As shown, the self-supporting module also includes a first traction roller 213, an infrared pre-curing unit 214, a support roller 215, a slitting device 216, and a second traction roller 217. These structures are sequentially arranged after the multi-stage rolling module 212. The infrared pre-curing unit 214 is spaced 5 cm apart from the multi-stage rolling module 212 and uses infrared light with a wavelength of 2.5-5 μm to pre-cur the film material, facilitating subsequent processing. This wavelength of infrared light matches the vibrational frequency of the self-supporting film material molecules. When radiated to the material surface, the light energy is efficiently absorbed by polar molecules and converted into heat energy. In the pre-curing unit, the polymer chain segments of the self-supporting film undergo intensified movement due to heating, promoting cross-linking reactions or crystallization, improving the structural stability and mechanical strength of the film. Furthermore, the wavelength has moderate penetration, enabling uniform heating of the material inside and out, avoiding surface overheating damage.

[0032] Specifically, the slitting device 216 is used to remove the rough edges on both sides of the width direction of the self-supporting membrane, with a cutting accuracy of ±0.1mm. The slitting device 216 can be a membrane material cutting device in the prior art.

[0033] Specifically, refer to Figure 3 As shown, the pretreatment unit 1 includes, in sequence along the unwinding direction of the current collector, a first correction sensor 11, a first correction roller 12, an ion cleaner 13, a first microgravure coating machine 14, a first pre-curing oven 15, a first back roller 16, a second microgravure coating machine 17, a second pre-curing oven 18, and an infrared activation box 19.

[0034] After the current collector unwinds from the unwind roller 0, the current collector passes through the first correction sensor 11. The first correction sensor 11 monitors the position of the current collector in real time. Once a positional deviation is detected, it is immediately fed back to the first correction roller 12. The first correction roller 12 adjusts its own angle or position to correct the running direction of the current collector, ensuring its smooth entry into subsequent processes. This is how the two work together to achieve positioning correction of the current collector during the conveying process, avoiding uneven processing or poor composite due to deviation. The specific structure of the first correction sensor 11 and the first correction roller 12, as well as the information transmission and control methods, can all adopt existing correction sensors, correction rollers, and corresponding information transmission and control methods.

[0035] After the current collector enters the ion cleaner 13, surface impurities are removed and the surface is activated to facilitate subsequent coating. Specifically, refer to... Figure 4As shown, the ion cleaner 13 includes a reaction chamber 131, a metering inlet 133, and a molecular pump 134. The reaction chamber 131 has slots at both ends to accommodate the current collector. Parallel electrodes 135 are respectively located on the upper and lower sides of the current collector within the reaction chamber 131. The metering inlet 133 is connected to the reaction chamber 131, and the molecular pump 134 is also connected to the reaction chamber 131. The metering inlet 133 and the molecular pump 134 provide suitable conditions for the plasma reaction within the reaction chamber 131. With the anode on top and the cathode on the bottom of the parallel electrodes 135, an electric field is applied to generate plasma, which bombards the surface of the current collector, removing impurities such as oil and oxides, while simultaneously activating the surface and enhancing the adhesion of subsequent coatings.

[0036] Reference Figure 5 As shown, a telescopic scraper 132 is provided on the slot. One side of the telescopic scraper 132 is in contact with the current collector, and the other side is connected to the wall of the slot through a telescopic component. The telescopic component can be a spring or a specific elastic structure, enabling the telescopic scraper 132 to adhere to the surface of the current collector, scraping away surface impurities while preventing plasma leakage from the reaction chamber 131. In this embodiment, a corresponding mounting groove can be provided on the slot, and the telescopic scraper 132 can be installed in the mounting groove, with the telescopic scraper 132 arranged at an angle so that the contact point between the telescopic scraper 132 and the current collector forms a rounded corner. The telescopic scraper 132 is made of polyimide with a Shore A hardness of 90A, and applies a pressure of 200-400 kPa to the surface of the current collector.

[0037] Specifically, the first back roller 16 changes the movement direction of the current collector from a first horizontal direction to a second horizontal direction, the first horizontal direction being opposite to the second horizontal direction, so that the first microgravure coating machine and the second microgravure coating machine 17 respectively coat both sides of the current collector. By adjusting the direction of the current collector by the first back roller 16, the first microgravure coating machine and the second microgravure coating machine 17 can coat both sides of the current collector respectively, which facilitates the arrangement of the microgravure coating machines and also facilitates the subsequent lamination of both sides of the current collector with a self-supporting film.

[0038] Specifically, in this embodiment, the first microgravure coating machine and the second microgravure coating machine 17 have the same structure. (Refer to...) Figure 6As shown, the first microgravure coating machine includes a glue tank 141, a ceramic anilox roller 142, a limiting roller 144, and a scraper 143. The ceramic anilox roller 142 is rotatably mounted in the glue tank 141. The limiting roller 144 is located above the ceramic anilox roller 142 and forms a gap between it and the ceramic anilox roller 142 to accommodate the flow of the current collector. The scraper 143 is mounted on the glue tank 141 and contacts the ceramic anilox roller 142. When the current collector passes through the first microgravure coating machine 14, the ceramic anilox roller 142 rotates in the glue tank 141, the cells absorb the adhesive, and the scraper 143 scrapes off excess slurry from the surface of the ceramic anilox roller 142, leaving only the adhesive in the cells. The current collector passes through the gap between the limiting roller 144 and the ceramic anilox roller 142. The limiting roller 144 is located at the upper end of the ceramic anilox roller 142, which limits the current collector and ensures its fit with the ceramic anilox roller 142, so that the adhesive in the cells of the ceramic anilox roller 142 can be uniformly transferred to the surface of the current collector, achieving precise micron-level thickness coating.

[0039] Specifically, refer to Figure 7 As shown, the infrared activation chamber 19 includes infrared radiators 219 arranged vertically opposite each other, with a wavelength range of 2.5-5 μm. This wavelength of infrared light matches the vibrational frequency of the adhesive layer molecules. When radiated onto the material surface, the light energy is efficiently absorbed by the polar molecules and converted into heat energy. In the activation chamber, the adhesive layer rapidly heats to 80-100°C, enhancing molecular activity and dramatically increasing viscosity, thus providing excellent bonding strength for the composite.

[0040] Specifically, the composite unit 3 includes composite rollers, namely a first composite roller 31 and a second composite roller 32, respectively disposed on both sides of the current collector. The surface temperature of the first composite roller 31 and the second composite roller 32 is controlled at 100℃±5℃, and the roller pressure is adjusted within the range of 5-20MPa. At this temperature, the adhesive in the self-supporting membrane is in a molten state, the molecular chain segment mobility is enhanced, and the wettability with the surface of the current collector is improved. Under this pressure, the current collector and the self-supporting membrane are tightly bonded, the internal pores are compacted, and the adhesive molecules are promoted to form physical intercalation and chemical adsorption with the surface of the current collector, thereby achieving a high-strength interfacial bond and firmly bonding the self-supporting membrane and the current collector together. After the current collector is pre-bonded with the self-supporting membrane, a composite electrode is formed.

[0041] Specifically, the winding unit 4, along the moving direction of the composite electrode sheet, includes a third back roller 41, a fourth traction roller 42, a second correction sensor 43, a second correction roller 44, a tension sensor 45, and a composite electrode sheet winding roller 46. A second back roller 110 is provided between the pretreatment unit 1 and the self-supporting film supply unit 2, which adjusts the moving direction of the current collector from horizontal to vertical. A third back roller 41 is provided at the beginning of the winding unit 4, which adjusts the moving direction of the current collector from vertical to horizontal. By adjusting the moving direction of the current collector, it is made to be in a vertical state when passing through the self-supporting film supply unit 2, facilitating the arrangement of the first self-supporting module 21 and the second self-supporting module 22 on both sides of the current collector, making the entire composite device more compact and maximizing space utilization.

[0042] Specifically, the composite electrode sheet's position is monitored in real time by the second alignment sensor 43. Based on the detection results, the second alignment roller 44 is controlled to perform alignment correction. The tension sensor 45 monitors the tension of the composite electrode sheet, and the winding speed of the composite electrode sheet take-up roller 46 is controlled based on the monitored tension to achieve stable winding. The specific structure of the tension sensor 45, the composite electrode sheet take-up roller 46, and the corresponding control methods can adopt existing technologies.

[0043] This embodiment integrates the coating process of the current collector and the composite process of the dry electrode. By using an ion cleaner 13 for plasma cleaning and activation, combined with a micro-gravure coating machine for precise adhesive application, a pre-curing oven for hot air semi-curing, and an infrared activation box 19 for activating the adhesive, the surface cleanliness of the current collector is significantly improved. The adhesive thickness deviation is strictly controlled within ±0.1μm, greatly improving the activation efficiency of the adhesive layer. It also has a preheating effect on the current collector, which not only enhances the bonding force of the composite interface but also reduces defects such as bubbles and delamination, thereby improving the product qualification rate and long-term stability.

[0044] Work process: Step 1: The current collector is released through the unwinding roller 0. After the position is detected by the first correction sensor 11, the position is corrected by the first correction roller 12. The corrected current collector enters the ion cleaner 13 and is surface cleaned in the vacuum reaction chamber 131 by the plasma generated by the parallel electrode 135. The cleaning time is 5-8 seconds.

[0045] Step 2: The cleaned current collector enters the first micro-gravure coating machine 14, where a ceramic anilox roller 142 and a limiting roller 144 cooperate to coat the first side with an adhesive layer. It is then pre-cured in the first pre-curing oven 15 (temperature 80-100℃, time 10-15s). Subsequently, it is flipped over by the first back roller 16, and a second micro-gravure coating machine 17 coats the second side with an adhesive layer. It is then pre-cured in the second pre-curing oven 18 (temperature 80-100℃, time 10-15s).

[0046] Step 3: The current collector after double-sided coating enters the infrared activation box 19 to activate the adhesive layer at a temperature of 80-100℃ for 5-8 seconds, and then moves vertically downwards via the second back roller 110.

[0047] Step 4: The self-supporting unwinding roller 211 releases the self-supporting film, which is then rolled through four sets of pre-pressing rollers 218 with decreasing gaps in sequence by the multi-stage rolling module 212. After that, it is pre-cured by the infrared pre-curing unit 214 (curing time 8-12s), and then the slitting device 216 removes the rough edges on both sides (cutting accuracy ±0.1mm).

[0048] Step 5: The vertically downward current collector and the pre-treated self-supporting films on both sides are pressed together between the first composite roller 31 and the second composite roller 32 (temperature 100℃±5℃, pressure 10 MPa) to form a composite electrode.

[0049] Step 6: The composite electrode sheet moves horizontally via the third back roller 41, and its thickness and temperature distribution are detected by the online detection component. Then, its position is corrected a second time by the second correction sensor 43 and the second correction roller 44. Finally, it is wound up by the composite electrode sheet take-up roller 46.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A dry-process self-supporting membrane and current collector composite device, characterized in that, It includes a current collector unwinding roller, a pretreatment unit, a self-supporting film supply unit, a composite unit, and a winding unit arranged sequentially along the unwinding direction of the current collector; The pretreatment unit includes a coating machine and a pre-curing oven; the coating machine is used to coat the current collector, and the pre-curing oven is used to cure the coated current collector. The self-supporting film supply unit includes self-supporting modules arranged on both sides of the current collector; the self-supporting module includes a self-supporting unwinding roller and a multi-stage rolling module in sequence along the unwinding direction of the self-supporting film; the multi-stage rolling module includes multiple pre-pressing rollers arranged in parallel, so that a pre-pressing gap is formed between adjacent pre-pressing rollers, and the pre-pressing gap gradually decreases along the unwinding direction of the self-supporting film.

2. The dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, The multi-stage roll forming module includes four pre-pressing rollers arranged in parallel. The four pre-pressing rollers form pre-pressing gaps of 0.5 mm, 0.3 mm and 0.1 mm in size along the unwinding direction of the self-supporting film.

3. The dry self-supporting membrane and current collector composite device according to claim 2, characterized in that, The preload roller adopts a convex curved surface design, and the roller convexity of the preload roller is 0.05mm.

4. The dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, The pretreatment unit includes, in sequence along the unwinding direction of the current collector, a first microgravure coating machine, a first pre-curing oven, a first back roller, a second microgravure coating machine, and a second pre-curing oven. The first back roller changes the movement direction of the current collector from a first horizontal direction to a second horizontal direction, the first horizontal direction being opposite to the second horizontal direction, so that the first micro-gravure coating machine and the second micro-gravure coating machine coat both sides of the current collector respectively.

5. The dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, An ion cleaner is also provided between the current collector unwinding roller and the coating machine. The ion cleaner includes a reaction chamber, a metering inlet device, and a molecular pump. The two ends of the reaction chamber are respectively provided with slots to accommodate the current collector passing through. Parallel electrodes are respectively provided on the upper and lower sides of the current collector in the reaction chamber. The metering inlet device is connected to the reaction chamber. The molecular pump is connected to the reaction chamber.

6. The dry self-supporting membrane and current collector composite device according to claim 5, characterized in that, The slot is equipped with a telescopic scraper, one side of which is in contact with the collector, and the other side is connected to the wall of the slot through a telescopic component.

7. The dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, The coating machine includes a glue tank, a ceramic anilox roller, a limiting roller, and a scraper; the ceramic anilox roller is rotatably installed in the glue tank; the limiting roller is located above the ceramic anilox roller and forms a gap with the ceramic anilox roller to accommodate the flow of the current collector; the scraper is installed on the glue tank and contacts the ceramic anilox roller.

8. The dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, The composite unit includes composite rollers respectively disposed on both sides of the current collector.

9. A dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, A second back roller is provided between the pretreatment unit and the self-supporting film supply unit. The second back roller adjusts the movement direction of the current collector from the horizontal direction to the vertical direction. A third back roller is provided at the beginning of the winding unit. The third back roller adjusts the movement direction of the current collector from the vertical direction to the horizontal direction.

10. A dry self-supporting membrane and current collector composite device according to claim 1, characterized in that, The current collector unwinding unit also includes a first correction sensor and a first correction roller.

Images