Pole piece coating and drying production line
By combining the preheating and heating devices in the electrode coating and drying production line, the problem of traditional electrode coating production lines being unable to adapt to the drying of different electrode materials has been solved, realizing an efficient and flexible electrode drying process and improving the yield and coating quality of the electrodes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 国兴(东莞)新能源科技有限公司
- Filing Date
- 2025-05-07
- Publication Date
- 2026-04-28
AI Technical Summary
Traditional electrode coating production lines struggle to meet the varying drying requirements of different electrode materials, coating thicknesses, and solvent systems, leading to problems such as electrode cracking or low drying efficiency.
Design an electrode coating and drying production line that adopts a flexible combination of preheating and heating devices, including interchangeable combinations of air-cooled ovens and large roller heating structures. Through non-contact hot air preheating and contact heating, a three-stage process is formed to adapt to the differentiated needs of different electrodes.
It improves the yield of electrode sheets, avoids solvent residue inside thick coatings and mechanical damage to thin coatings, and enhances drying efficiency and coating depth curing effect.
Smart Images
Figure CN224167928U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of electrode manufacturing, and in particular to an electrode coating and drying production line. Background Technology
[0002] In the lithium battery production process, the electrode sheet is a core component, and its performance directly affects the quality and service life of the entire equipment. The coating and drying process of the electrode sheet is one of the key links that determines the performance of the electrode sheet. The quality of the drying effect will affect important indicators such as the uniformity of the electrode sheet thickness, the adhesion of the coating, and the stability of the internal structure.
[0003] Traditional electrode coating production lines typically employ a single heating structure, such as a standalone large roller heating device or oven. This makes it difficult to meet the diverse drying requirements of different electrode materials, coating thicknesses, and solvent systems. While the large roller heating device, which directly contacts the electrode via a heat-conducting roller, offers high thermal conductivity, its temperature regulation capability is insufficient. For thinner electrodes or those with poor coating flexibility, localized stress concentration or excessively high temperatures can easily lead to electrode cracking. Ovens, which provide heat through hot air circulation, avoid contact stress damage to the electrode, but their drying efficiency is low. For electrode coating systems with greater thickness or a high solvent volume ratio, the oven length needs to be extended or the coating speed reduced to meet drying requirements, making them unsuitable for high-speed production lines. Therefore, designing an electrode coating and drying production line that can flexibly adapt to the diverse needs of different electrodes is a pressing issue for enterprise technical personnel. Utility Model Content
[0004] To address the shortcomings of the prior art, this application provides an electrode coating and drying production line.
[0005] The above-mentioned inventive objective of this application is achieved through the following technical solutions:
[0006] An electrode coating and drying production line, comprising:
[0007] An unwinding device that unwinds the electrode sheet;
[0008] A coating device for coating electrodes;
[0009] A preheating device that preheats the electrode sheets;
[0010] A heating device that heats the preheated electrode sheets;
[0011] The winding device winds up the heated electrode sheets.
[0012] Preferably, the preheating device is a fan-operated drying oven, and the heating device is a large roller heating structure.
[0013] Preferably, the preheating device is a large roller heating structure, and the heating device is a fan-operated drying oven.
[0014] Preferably, the electrode coating and drying production line further includes a curing device, wherein the preheating device is a fan-cooled oven, the heating device is a large roller heating structure, and the curing device is a fan-cooled oven.
[0015] Preferably, the electrode coating and drying production line further includes a curing device, wherein the preheating device is a large roller heating structure, the heating device is a conveying air drying oven, and the curing device is a large roller heating structure.
[0016] Preferably, the air-cooled oven includes a working chamber, a centrifugal fan, and a ventilation box. The working chamber has an inlet and an outlet at both ends, respectively. Several guide rollers for supporting the electrode are rotatably arranged inside the working chamber. Air hoods are symmetrically arranged on the upper and lower sides inside the working chamber. An exhaust pipe is connected to the top of the working chamber. The centrifugal fan is located outside the working chamber and connected to the ventilation box. A heating wire is installed inside the ventilation box. The ventilation box is connected to two air hoods. The temperature gradient of the electrode is controlled between 0-30℃.
[0017] Preferably, the large roller heating structure includes a mounting bracket, a heat-conducting roller, and a drive motor. The heat-conducting roller is rotatably mounted on the mounting bracket. The heat-conducting roller is connected to a heating device for heating the roller surface. The drive motor is used to drive the heat-conducting roller to rotate. The diameter of the heat-conducting roller is greater than 1m.
[0018] Preferably, the air-cooled oven is replaced by an infrared radiation box, which includes several groups of radiation components arranged along the conveying direction. Each radiation component includes an upper radiation plate and a lower radiation plate, which are used to irradiate the upper and lower sides of the electrode sheet, respectively.
[0019] Preferably, the air-cooled oven is replaced by an electric heating box, which includes several sets of electric heating components arranged along the conveying direction. Each electric heating component includes an upper heating plate and a lower heating plate, and both the upper and lower heating plates are provided with heating wires located on the upper and lower sides of the electrode sheet, respectively.
[0020] Preferably, the air-cooled oven is replaced by a liquid bath heating box, which includes several sets of liquid bath heating components arranged along the conveying direction. Each liquid bath heating component includes an upper liquid bath plate and a lower liquid bath plate. Both the upper and lower liquid bath plates are connected to an external liquid bath device and are located on the upper and lower sides of the electrode, respectively.
[0021] Compared with existing technologies, the beneficial effects of this utility model are as follows: This electrode coating and drying production line, through the flexible combination of preheating and heating devices—that is, the interchangeable combination of the air-cooled oven and the large roller heating structure—breaks through the limitations of traditional single heating methods. When drying electrodes with thick coatings and high solvent systems, such as the positive electrode of power batteries, the combination of preheating with the large roller heating structure and heating with the air-cooled oven allows for the rapid removal of most of the solvent through efficient heat conduction via the large roller contact. Furthermore, the temperature is controlled by the hot air circulation gradient in the air-cooled oven, which avoids bubbling and delamination defects caused by solvent residue inside the thick coating. This eliminates the need to extend the length of the air-cooled oven or reduce the coating speed. When drying ultra-thin electrodes such as silicon-based anodes and lithium metal coatings, a non-contact, gentle hot air preheating method using a fan-operated drying oven is employed to enhance the initial strength of the coating. Then, a large roller heating structure provides contact heating to improve drying efficiency. This avoids the indentation and cracking problems caused by direct contact between the large roller and the undried thin coating, thus increasing the electrode yield. Furthermore, by adding a curing device, a three-stage process of preheating, heating, and curing can be formed to achieve deep curing of the coating, suitable for electrodes with multi-layer composite coating systems. The flexible combination of these preheating and heating devices allows for adaptability to the diverse needs of different electrodes.
[0022] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the electrode coating and drying production line in Embodiment 1 of this application;
[0024] Figure 2 This is a schematic diagram of the electrode coating and drying production line in Embodiment 2 of this application;
[0025] Figure 3 This is a schematic diagram of the electrode coating and drying production line in Embodiment 3 of this application;
[0026] Figure 4 This is a schematic diagram of the electrode coating and drying production line in Embodiment 4 of this application;
[0027] Figure 5 This is a schematic diagram of the structure of a fan-operated drying oven in one embodiment of this application;
[0028] Figure 6 This is a cross-sectional structural schematic diagram of a fan-operated drying oven in one embodiment of this application;
[0029] Figure 7 This is a cross-sectional structural diagram of an infrared radiation box in one embodiment of this application;
[0030] Figure 8This is a cross-sectional structural diagram of an electric heating box in one embodiment of this application.
[0031] Reference numerals: 1. Unwinding device; 2. Coating device; 3. Preheating device; 4. Heating device; 5. Rewinding device; 6. Air-cooled oven; 61. Working chamber; 62. Centrifugal fan; 63. Ventilation box; 64. Guide roller; 65. Air hood; 66. Exhaust pipe; 7. Large roller heating structure; 71. Mounting bracket; 72. Heat-conducting roller; 8. Curing device; 9. Infrared radiation box; 10. Radiation assembly; 101. Upper radiation plate; 102. Lower radiation plate; 11. Electric heating box; 12. Electric heating assembly; 121. Upper electric heating plate; 122. Lower electric heating plate. Detailed Implementation
[0032] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of this application, including various details to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.
[0033] It should be noted that the terms "first," "second," etc., used in this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. The implementation methods described in the following exemplary embodiments do not represent all implementation methods consistent with this disclosure.
[0034] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article, unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship.
[0035] The following is a reference appendix. Figure 1 To be continued Figure 8 This application describes an electrode coating and drying production line.
[0036] like Figure 1As shown, the electrode coating and drying production line includes an unwinding device 1, a coating device 2, a preheating device 3, a heating device 4, and a winding device 5 arranged in sequence. The unwinding device 1 unwinds the electrode, the coating device 2 coats the electrode, the preheating device 3 preheats the electrode, the heating device 4 heats the preheated electrode, and the winding device 5 winds the heated electrode. By setting the preheating device 3 and the heating device 4, different heating processes can be performed before and after the electrode, that is, the electrode can be dried in segments.
[0037] It should be noted that both the unwinding device 1 and the winding device 5 can be conventional roll winding and unwinding equipment available on the market to complete the winding and unwinding process of the electrode roll. The coating device 2 can be conventional roller coating, spray coating, or scraper coating equipment available on the market for coating the electrode.
[0038] It should also be noted that the temperature gradient of the electrode sheet should be controlled within 30°. A temperature preheating mechanism can be added to the output end of the coating device 2 to achieve the effect of pre-drying the slurry. The temperature preheating mechanism can use infrared radiation preheating, microwave-assisted preheating, electric heating preheating, etc. to preheat the output slurry. The specific installation method of the coating device 2 and the temperature preheating mechanism is common knowledge to those skilled in the art and will not be described in detail here.
[0039] Specifically, such as Figure 1 As shown, in one embodiment (here designated as Embodiment 1), the preheating device 3 is a fan-operated oven 6, and the heating device 4 is a large roller heating structure 7. The combination of preheating with the fan-operated oven 6 and heating with the large roller heating structure 7 allows for the pre-drying of thin-coated electrode systems such as silicon-based anodes and lithium metal coatings. The fan-operated oven 6 can improve the initial strength of the coating through gentle hot air pre-drying, and the large roller heating structure 7 can precisely control the temperature to uniformly dry the entire electrode. This avoids the problems of indentation and cracking caused by the traditional single large roller heating structure 7 directly contacting the undried coating.
[0040] like Figure 2 As shown, in another embodiment (here designated as Embodiment 2), the preheating device 3 is a large roller heating structure 7, and the heating device 4 is a fan-operated drying oven 6. The combination of preheating with the large roller heating structure 7 and heating with the fan-operated drying oven 6 is effective when drying electrodes with thick coatings and high solvent systems. The combination of preheating with the large roller heating structure 7 and heating with the fan-operated drying oven 6 can quickly remove most of the solvent through efficient heat conduction via the large roller contact. Furthermore, the temperature is controlled by the hot air circulation gradient in the fan-operated drying oven 6, which can avoid bubbling and delamination defects caused by solvent residue inside the thick coating without extending the length of the fan-operated drying oven 6 or reducing the coating speed.
[0041] It should be noted that, for example, the positive electrode of power batteries (such as NCM811 and lithium iron phosphate) are all electrodes with thick coatings or high solvent systems. Their wet coating thickness can reach 100-300μm, and they use high-viscosity NMP solvent systems. First, the large roller contact heat conduction can quickly remove 60%-80% of the solvent. Due to the protection of the coating thickness, the electrode can be protected from damage during the large roller contact heat conduction, and it can also play a role in preheating. Finally, the hot air circulation of the air-cooled oven 6 is used to achieve gradient temperature control, avoiding bubbling and delamination defects caused by solvent residue inside the thick coating. Among them, compared with the traditional single oven heating structure, the efficient preheating of the large roller heating structure 7 can improve the drying efficiency and reduce the solvent residue rate.
[0042] As a preferred option, such as Figure 3 As shown, in one embodiment (here designated as Embodiment 3), the electrode coating drying production line further includes a curing device 8, a preheating device 3 which is a conveyor air oven 6, a heating device 4 which is a large roller heating structure 7, and a curing device 8 which is a conveyor air oven 6. By setting the curing device 8 and combining the conveyor air oven 6, the large roller heating structure 7, and the conveyor air oven 6, a three-stage process of gentle preheating, efficient initial drying, and precise curing is formed, which is suitable for drying multi-layer composite coatings (such as electrodes containing particles of different sizes).
[0043] As a preferred option, such as Figure 4 As shown, in one embodiment (here designated as Embodiment 4), the electrode coating drying production line further includes a curing device 8, a preheating device 3 which is a large roller heating structure 7, a heating device 4 which is a conveying air oven 6, and a curing device 8 which is a large roller heating structure 7. By setting up the curing device 8 and by combining the large roller heating structure 7, the conveying air oven 6, and the large roller heating structure 7, a three-stage process of rapid initial drying, gentle heating, and contact curing is formed, which is suitable for coatings that require high thermal conductivity to complete the final densification (such as metal-based conductive coatings).
[0044] In addition, such as Figure 5 and Figure 6As shown, the air-cooled oven 6 includes a working chamber 61, a centrifugal fan 62, and a ventilation box 63. The working chamber 61 has an inlet and an outlet at both ends. Several guide rollers 64 for supporting the electrode sheets are rotatably arranged inside the working chamber 61. Air hoods 65 are symmetrically arranged on both the upper and lower sides of the working chamber 61. An exhaust pipe 66 connects to the top of the working chamber 61. The centrifugal fan 62 is located outside the working chamber 61 and connected to the ventilation box 63. A heating wire (not shown in the figure) is installed inside the ventilation box 63. The ventilation box 63 is connected to the two air hoods 65. The temperature gradient of the electrode sheets is controlled between 0-30℃. During operation, the air-cooled oven 6 uses centrifugal fans... The fan 62 delivers external air into the heating wire inside the ventilation box 63 to heat it, forming high-temperature hot air. This hot air is then evenly blown onto both sides of the electrode through the symmetrically arranged air hoods 65, thus achieving non-contact heat conduction. The guide rollers 64 support the electrode for stable transport, preventing sagging or wrinkling. The exhaust pipe 66 promptly discharges the volatile solvent vapors, maintaining the efficiency of inward air convection. The structure of this air-cooled drying box 6, through hot air circulation and symmetrical air delivery design, creates a uniformly heated drying environment, avoiding mechanical damage to the electrode caused by contact heating. Furthermore, the controllable hot air flow rate and temperature distribution meet the requirements for gentle drying, significantly improving the surface quality and drying consistency of the electrode.
[0045] In addition, such as Figure 1 As shown, the large roller heating structure 7 includes a mounting bracket 71, a heat-conducting roller 72, and a drive motor (not shown in the figure). The heat-conducting roller 72 is rotatably mounted on the mounting bracket 71 and is connected to a heating device 4. The heating device 4 is used to heat the roller surface of the heat-conducting roller 72. The drive motor is used to drive the heat-conducting roller 72 to rotate. The diameter of the heat-conducting roller is greater than 1m. During operation, the large roller heating structure 7 uniformly heats the roller surface of the heat-conducting roller 72 through the heating device 4. The electrode moves against the roller surface under tension and quickly absorbs heat through contact conduction. The drive motor synchronously controls the rotation speed of the heat-conducting roller 72 to match the running speed of the electrode.
[0046] It should be noted that the heating device 4 can be any commercially available device that can heat the roller surface, such as a liquid bath heater or an electric heater; there are no restrictions here.
[0047] It should also be noted that, in one embodiment, as Figure 7 As shown, the aforementioned air-cooled oven 6 can be replaced with an infrared radiation box 9. The infrared radiation box 9 includes several groups of radiation components 10 arranged along the conveying direction. Each radiation component 10 includes an upper radiation plate 101 and a lower radiation plate 102. The upper radiation plate 101 and the lower radiation plate 102 are respectively used to irradiate the upper and lower sides of the electrode. By replacing the air-cooled oven 6 with the infrared radiation box 9, heating can be carried out using a non-contact heat conduction method of infrared radiation according to different working conditions. The working principle of the upper radiation plate 101 and the lower radiation plate 102 is common knowledge to those skilled in the art and will not be described in detail here.
[0048] In another embodiment, such as Figure 8 As shown, the air-cooled oven 6 is replaced by an electric heating box 11. The electric heating box 11 includes several sets of electric heating components 12 arranged along the conveying direction. The electric heating components 12 include an upper heating plate 121 and a lower heating plate 122. Both the upper heating plate 121 and the lower heating plate 122 are provided with heating wires and are located on the upper and lower sides of the electrode respectively. By replacing the air-cooled oven 6 with the electric heating box 11, heating can be carried out by non-contact heat conduction using electric heating according to different working conditions. The working principle of the upper heating plate 121 and the lower heating plate 122 is common knowledge to those skilled in the art and will not be described in detail here.
[0049] In another embodiment, the air-cooled oven 6 is replaced by a liquid bath heating box (not shown in the figure). The liquid bath heating box includes several sets of liquid bath heating components (not shown in the figure) arranged along the conveying direction. The liquid bath heating components include an upper liquid bath plate and a lower liquid bath plate. The upper liquid bath plate and the lower liquid bath plate are both connected to an external liquid bath device (not shown in the figure) and are located on the upper and lower sides of the electrode respectively. By replacing the air-cooled oven 6 with a liquid bath heating box, heating can be carried out by non-contact heat conduction method of liquid bath heating according to different working conditions. The external liquid bath device is a commonly used liquid bath heating device 4 on the market. Usually, the circulating liquid inside the device is heated and then fed into the liquid bath plate for circulation to provide heating function. The working principle of the upper liquid bath plate and the lower liquid bath plate is common knowledge to those skilled in the art and will not be described in detail here.
[0050] The beneficial effects of the electrode coating and drying production line of this application are as follows: the electrode coating and drying production line breaks through the limitations of the traditional single heating method by flexibly combining the preheating and heating device 4, that is, the air-cooled oven 6 and the large roller heating structure 7 can be interchanged.
[0051] When drying ultra-thin electrode sheets such as silicon-based anodes and lithium metal coatings, a non-contact, gentle hot air preheating method using a conveyor oven 6 is adopted to enhance the initial strength of the coating. Then, contact heating is carried out through a large roller heating structure 7 to improve drying efficiency. This avoids the problems of indentation and cracking caused by direct contact between the traditional large roller and the undried thin coating, thereby improving the yield of electrode sheets.
[0052] When drying electrodes with thick coatings and high solvent systems, such as the positive electrode of a power battery, a combination of preheating with a large roller heating structure 7 and heating with a circulating air oven 6 can quickly remove most of the solvent through efficient heat conduction via the large roller. Then, the circulating air oven 6 controls the temperature through hot air gradient, avoiding bubbling and delamination defects caused by solvent residue inside the thick coating. There is no need to extend the length of the circulating air oven 6 or reduce the coating speed. Furthermore, by adding a curing device 8, a three-stage process of preheating, heating, and curing can be formed to achieve deep curing of the coating. This is suitable for electrodes with multi-layer composite coating systems. Through the flexible combination of the preheating device 3, heating device 4, and curing device 8, the different needs of different electrodes can be flexibly adapted.
[0053] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An electrode coating and drying production line, characterized in that, include: Unwinding device (1), which unwinds the electrode sheet; Coating device (2), which coats the electrode sheet; The preheating device (3) preheats the electrode sheets; Heating device (4) heats the preheated electrode sheet; The winding device (5) winds up the heated electrode sheet.
2. The electrode coating and drying production line as described in claim 1, characterized in that, The preheating device (3) is a fan-operated drying oven (6), and the heating device (4) is a large roller heating structure (7).
3. The electrode coating and drying production line as described in claim 1, characterized in that, The preheating device (3) is a large roller heating structure (7), and the heating device (4) is a fan-operated drying oven (6).
4. The electrode coating and drying production line as described in claim 1, characterized in that, It also includes a curing device (8), the preheating device (3) is a fan-operated oven (6), the heating device (4) is a large roller heating structure (7), and the curing device (8) is a fan-operated oven (6).
5. The electrode coating and drying production line as described in claim 1, characterized in that, It also includes a curing device (8), the preheating device (3) is a large roller heating structure (7), the heating device (4) is a fan-operated oven (6), and the curing device (8) is a large roller heating structure (7).
6. The electrode coating and drying production line according to any one of claims 1 to 5, characterized in that, The air-cooled oven (6) includes a working chamber (61), a centrifugal fan (62), and a ventilation box (63). The working chamber (61) has an inlet and an outlet at both ends. The working chamber (61) has a number of guide rollers (64) for supporting the electrode sheets. The working chamber (61) has symmetrically arranged wind hoods (65) on both the upper and lower sides. The top of the working chamber (61) is connected to an exhaust pipe (66). The centrifugal fan (62) is located outside the working chamber (61) and connected to the ventilation box (63). The ventilation box (63) has a heating wire inside and is connected to two wind hoods (65). The temperature gradient of the electrode sheets is controlled between 0-30℃.
7. An electrode coating and drying production line as described in any one of claims 1 to 5, characterized in that, The large roller heating structure (7) includes a mounting bracket (71), a heat-conducting roller (72), and a drive motor. The heat-conducting roller (72) is rotatably mounted on the mounting bracket (71). The heat-conducting roller (72) is connected to a heating device (4). The heating device (4) is used to heat the roller surface of the heat-conducting roller (72). The drive motor is used to drive the heat-conducting roller (72) to rotate. The diameter of the heat-conducting roller is greater than 1m.
8. An electrode coating and drying production line as described in any one of claims 2 to 5, characterized in that, The air-cooled oven (6) is replaced by an infrared radiation box (9). The infrared radiation box (9) includes several groups of radiation components (10) arranged along the conveying direction. The radiation components (10) include an upper radiation plate (101) and a lower radiation plate (102). The upper radiation plate (101) and the lower radiation plate (102) are respectively used to irradiate the upper and lower sides of the electrode.
9. An electrode coating and drying production line as described in any one of claims 2 to 5, characterized in that, The air-cooled oven (6) is replaced by an electric heating box (11). The electric heating box (11) includes several sets of electric heating components (12) arranged along the conveying direction. The electric heating components (12) include an upper heating plate (121) and a lower heating plate (122). Both the upper heating plate (121) and the lower heating plate (122) are provided with heating wires and are located on the upper and lower sides of the electrode respectively.
10. An electrode coating and drying production line as described in any one of claims 2 to 5, characterized in that, The air-cooled oven (6) is replaced by a liquid bath heating box. The liquid bath heating box includes several sets of liquid bath heating components arranged along the conveying direction. The liquid bath heating components include an upper liquid bath plate and a lower liquid bath plate. The upper liquid bath plate and the lower liquid bath plate are both connected to an external liquid bath device and are located on the upper and lower sides of the electrode respectively.