A dry electrode rolling apparatus

Abstract

The application discloses a dry electrode rolling device, which comprises a rolling device body, a plurality of rollers, a lifting device and a gas supply device for supplying gas to the lifting device. The lifting device is arranged on the lower side of the roller and comprises an air outlet for blowing air towards the electrode film on the second roller. The horizontal distance between the air inlet of at least one air outlet and the lowest point of the second roller is L1 mm, and L1 mm is 43-65 mm. Under the action of air pressure, the electrode film is tightly attached to the roller surface of the second roller, avoiding its separation from the roller surface during the rolling and thinning process, thereby effectively preventing the electrode film from wrinkling. In turn, the problem of affecting the consistency and stability of battery performance caused by the uneven thickness of the electrode film due to wrinkling can be avoided.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a dry electrode rolling equipment. Background Technology

[0002] Dry electrode technology differs from traditional wet electrode fabrication processes. Traditional wet electrode fabrication requires large amounts of solvent to dissolve binders and active materials, forming a uniform slurry which is then coated onto the current collector. A lengthy drying process is then necessary to remove the solvent. Dry electrode technology, however, eliminates the need for large amounts of solvent, directly processing the electrode components into an electrode in a dry state, thus simplifying the manufacturing process.

[0003] The dry electrode preparation process is as follows: First, the active materials, binders and other dry electrode raw materials are fully mixed. Then, under certain pressure and temperature conditions, these raw materials are tightly bonded together and formed into a film with a certain strength and structure through a roller pressing device. This film is then directly composited onto the current collector to form an electrode.

[0004] In the film-forming process of a dry electrode rolling mill, the dry electrode raw material is gradually compacted and thinned before each roller, eventually forming the finished film. The rollers are arranged sequentially along the same plane, and the film passes between them in turn, alternating between the upper and lower sides of the rollers. When the roller speed is high, the portion of the film on the lower side of the roller is prone to deflection deformation on the bottom surface, causing the film to slightly detach from the roller surface. Because of this slight detachment, when the film enters the next roller for thinning, wrinkling can easily occur, making film formation difficult and affecting the electrode lamination effect and production efficiency.

[0005] Therefore, how to prevent the film from detaching from the roller surface and avoid wrinkling of the film during the thinning process is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] In view of this, the purpose of this application is to provide a dry electrode rolling device to prevent the film from detaching from the roller surface and to avoid wrinkling of the film during the thinning process.

[0007] To achieve the above objectives, this application provides the following technical solution:

[0008] The first aspect of this application provides a dry electrode rolling apparatus, comprising:

[0009] The main body of the roll forming equipment includes multiple parallel rolls. A thinning zone for compacting and thinning the electrode film is formed between any two adjacent rolls. Among the rolls, the roll that mates with the electrode film on the upper side of the roll surface is the first roll, and the roll that mates with the electrode film on the lower side of the roll surface is the second roll.

[0010] A wind-pressure lifting system includes a lifting device and an air supply device for supplying air to the lifting device. The lifting device is disposed on the lower side of the roll and includes an air outlet for blowing air toward the electrode diaphragm on the second roll.

[0011] Within the cross-section of the second roll, the horizontal distance between the air outlet's air contact point and the lowest point of the second roll is L1mm, where L1mm is 43mm~65mm. The air contact point is the intersection of the air outlet's air outlet direction and the outer contour of the second roll.

[0012] The dry electrode rolling equipment provided in this application adds a pneumatic lifting system to the main body of the rolling equipment. This pneumatic lifting system includes a lifting device located below the rolls. Air is blown onto the electrode film on the second roll through the air outlet of the lifting device. Under the action of the pneumatic pressure, the electrode film adheres tightly to the surface of the second roll, preventing it from detaching from the roll surface during the rolling and thinning process, thus effectively preventing wrinkling of the electrode film. This avoids uneven thickness caused by wrinkling of the electrode film, which affects the consistency and stability of battery performance. The pneumatic lifting system of this application ensures that the electrode film remains flat during the compaction and thinning process, improving the overall quality of the electrode film. Attached Figure Description

[0013] 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.

[0014] Figure 1 This is a schematic diagram of the dry electrode rolling equipment disclosed in the embodiments of this application;

[0015] Figure 2 This is a schematic diagram of the dry electrode rolling equipment disclosed in this application after removing some of its structures.

[0016] Figure 3 This is a side view of the dry electrode rolling equipment disclosed in this application after removing part of its structure;

[0017] Figure 4 This is a schematic diagram of the lifting device disclosed in the embodiments of this application;

[0018] Figure 5 This is a partial cross-sectional view of the dry electrode rolling equipment disclosed in the embodiments of this application;

[0019] Figure 6This is a cross-sectional view of the lifting device disclosed in the embodiments of this application.

[0020] The meanings of the various reference numerals in the figure are as follows:

[0021] 100 - Main body of the roller pressing equipment; 110 - Base frame; 120 - Top frame; 130 - Roll; 131 - First roll; 132 - Second roll; 140 - Support; 141 - First strip mounting hole; 142 - Second strip mounting hole;

[0022] 200-Wind pressure lifting system; 210-Lifting device; 211-Air outlet; 211a-First connection; 211b-Second connection; 212-Air outlet component; 213-Air outlet cavity; 220-Air supply pipeline; 230-Air supply device;

[0023] 300-Electrode film. Detailed Implementation

[0024] This application discloses a dry electrode rolling device to prevent the film from detaching from the roller surface and avoid wrinkling of the film during the thinning process.

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] A battery cell is the smallest charging and discharging unit of a battery. A battery cell is formed by winding or stacking a positive electrode, a negative electrode, and a separator between them. The positive electrode includes a positive current collector and a positive active material. The positive current collector can be made of metals such as aluminum foil, nickel foil, or stainless steel, or a composite foil formed by combining metals and insulating materials. The positive active material includes the main positive active material, conductive agent, and binder. The main positive active material includes one or more lithium-containing positive active materials such as lithium iron phosphate, ternary materials containing nickel, cobalt, and manganese, and lithium manganese iron phosphate.

[0027] Similarly, the negative electrode sheet includes a negative current collector and a negative active material. The negative current collector can be made of metal materials such as copper foil, aluminum foil, and stainless steel, or it can be a composite foil material formed by combining metals and insulating materials. The negative active material includes the negative active material, conductive agent, binder, etc. The negative active material includes one or more of the following: artificial graphite, natural graphite, silicon carbide, silicon oxide, lithium titanate, etc.

[0028] The mainstream manufacturing processes for positive and negative electrodes currently include wet electrode fabrication and dry electrode fabrication. Dry electrode fabrication relies on dry electrode rolling equipment. During film formation, the dry electrode raw material is gradually compacted and thinned between the rollers, ultimately forming the finished film. The rollers are arranged sequentially along the same plane, and the film passes between them in sequence. The film's winding pattern between the rollers alternates between the upper and lower sides of the rollers. When the roller speed is high, the portion of the film on the lower side of the roller is prone to deflection deformation on the bottom surface of the roller, causing the film to slightly detach from the roller surface. Because the film slightly detaches from the roller surface of the previous roller, when the film enters the next roller for thinning, it is prone to wrinkling, making the film difficult to form, affecting the electrode composite effect and production efficiency.

[0029] To address the issue of diaphragm detachment from the roll surface, existing technologies offer two solutions: increasing the roll surface temperature and increasing the roll transfer speed ratio and adjusting the roll gap. Both methods require adjustments depending on the specific process formulation of the dry electrode raw material. Specifically, when increasing the roll surface temperature to solve the problem after adjusting the dry electrode raw material formulation, the roll surface temperature also needs adjustment; similarly, when increasing the roll transfer speed ratio and adjusting the roll gap, both the roll transfer speed ratio and the roll gap also need adjustment. This process is cumbersome, requires frequent manual intervention, is difficult to operate, and is prone to safety accidents due to fatigue.

[0030] Based on this, this application discloses a dry electrode rolling equipment that does not rely on adjusting the surface temperature of the rolls, nor on adjusting the roll transfer speed ratio and the roll gap between the rolls, and can also achieve the effect of preventing the film from detaching from the roll surface and avoiding wrinkling of the film during the thinning process.

[0031] like Figure 1 and Figure 2 As shown, the dry electrode rolling equipment disclosed in this application includes a rolling equipment body 100 and a wind pressure lifting system 200.

[0032] The main body 100 of the roller pressing equipment can be the same as that in the prior art, or it can be adapted structurally based on the need to add a wind pressure support system 200. The main body 100 of the roller pressing equipment includes multiple parallel-arranged rollers 130. The specific number of rollers 130 can be designed by those skilled in the art based on the thinning requirements. Two sets of rollers 130 can be arranged, with the axes of the two sets of rollers 130 arranged on the same plane, which is usually a horizontal plane. The two sets of rollers 130 are used to compact and thin the electrode films on both sides of the current collector.

[0033] For ease of understanding, the two sets of rolls 130 are respectively defined as the first set of rolls (e.g., Figure 3 The five rolls shown on the left) and the second set of rolls (as shown on the left) Figure 3 (The five rolls shown on the right) The first set of rolls is used to compact and thin the first side diaphragm, and the second set of rolls is used to compact and thin the second side diaphragm. The roll in the first set of rolls adjacent to the second set of rolls is called the first adjacent roll, and the roll in the second set of rolls adjacent to the first set of rolls is called the second adjacent roll. The first adjacent roll and the second adjacent roll are used to compact the first side diaphragm and the second side diaphragm on both sides of the current collector.

[0034] A thinning zone is formed between any two adjacent rollers 130 to compact and thin the electrode film 300, and the two rollers 130 on both sides of the thinning zone rotate in opposite directions. This arrangement allows the electrode film to be gradually conveyed from upstream to downstream, while being compacted and thinned by the rollers 130.

[0035] For ease of understanding, the roller 130 whose upper surface mates with the electrode diaphragm 300 is defined as the first roller 131, and the roller 130 whose lower surface mates with the electrode diaphragm 300 is defined as the second roller 132. Since the electrode diaphragm 300 is attached to the upper surface of the first roller 131, gravity ensures they remain in contact, thus requiring no intervention. However, the electrode diaphragm 300 is attached to the lower surface of the second roller 132. Due to gravity and the deformation of the electrode diaphragm 300 itself, it may not remain in contact with the second roller 132, causing the electrode diaphragm 300 to slightly detach from the roller surface. Intervention is necessary to prevent this from affecting product quality.

[0036] like Figures 4-6 As shown, the wind-pressure lifting system 200 includes a lifting device 210 and an air supply device 230 for supplying air to the lifting device 210. The lifting device 210 is disposed on the lower side of the roll 130 and includes an air outlet 211 for blowing air toward the electrode diaphragm 300 on the second roll 132. The air supply device 230 supplies air to the lifting device 210 and blows it out through the air outlet 211, acting on the electrode diaphragm 300 on the lower side of the second roll 132, applying upward gas pressure to the electrode diaphragm 300. The form of gas supplied by the air supply device 230 is not limited; it can be air or an inert gas. The structure of the air supply device 230 is also not limited; it can be an air pump, an air tank, or a compressor, as long as it can supply gas to the lifting device 210.

[0037] A single lifting device 210 may be provided, and the lifting device 210 may have multiple air outlets 211, with each second roller 132 corresponding to an air outlet 211. That is, in this embodiment, although only one lifting device 210 is provided, it can cover all or part of the second rollers 132, and provide corresponding air outlets 211 for the corresponding second rollers 132, so as to ensure that the lifting device 210 can provide corresponding air outlets 211 for the area where the electrode film 300 to be lifted is located.

[0038] Alternatively, a lifting device 210 can be provided on the lower side of each second roll 132 to lift the electrode diaphragm 300 that has detached from the roll surface of the second roll 132, so that the electrode diaphragm 300 adheres to the lower side of the roll surface of the second roll 132. Each lifting device 210 can be equipped with an independent air supply device 230, that is, each lifting device 210 is equipped with an independent air supply device 230, or several lifting devices 210 or all lifting devices 210 can share a single air supply device 230.

[0039] Within the cross-section of the second roll 132 (the cross-section is a section perpendicular to the axis of the second roll 132), the horizontal distance between the air outlet 211 and the lowest point of the second roll 132 is L1mm, where L1mm is 43mm~65mm. The air outlet is the intersection of the air outlet 211's air outlet direction and the outer contour of the second roll 132.

[0040] For example, L1mm can be 43mm, 45mm, 47mm, 49mm, 50mm, 52mm, 54mm, 56mm, 58mm, 60mm, 62mm, 65mm, etc. This embodiment does not limit the specific value of L1mm, and those skilled in the art can select it within the range of 43mm to 65mm based on their needs.

[0041] The dry electrode rolling equipment disclosed in this application adds a wind pressure lifting system 200 to the main body 100 of the rolling equipment. The wind pressure lifting system 200 includes a lifting device 210 located below the second roll 132. Air can be blown onto the second roll 132 through the air outlet of the lifting device 210, specifically onto the electrode film 300 located below the roll surface of the second roll 132. Under the action of wind pressure, the electrode film 300 adheres tightly to the roll surface of the second roll 132, preventing it from detaching from the roll surface during the rolling and thinning process, thus effectively preventing wrinkling of the electrode film 300. This avoids uneven thickness caused by wrinkling of the electrode film 300, which affects the consistency and stability of battery performance. The wind pressure lifting system 200 of this application ensures that the electrode film 300 remains flat during the rolling and thinning process, improving the overall quality of the electrode film 300.

[0042] Under the blowing action of the wind-pressure lifting system 200, the electrode diaphragm 300 is tightly bonded to the roller surface, allowing for a more uniform distribution of pressure applied by the roller to the electrode diaphragm 300. This facilitates a more uniform compaction effect, ensuring a uniform thickness of the entire electrode diaphragm 300, thereby improving the performance of the battery electrode. Because electrodes with uniform thickness exhibit more uniform ion transport and electron conduction during charging and discharging, they contribute to improving the battery's charging and discharging efficiency, capacity, and cycle life.

[0043] If the electrode diaphragm 300 wrinkles frequently, it may cause production interruptions, requiring machine shutdown for adjustment or replacement of the diaphragm, which reduces production efficiency. The air-blowing device can reduce the probability of wrinkling of the electrode diaphragm 300, decrease the number of shutdowns caused by diaphragm problems, make the production process smoother and more stable, and improve production efficiency.

[0044] In one specific embodiment of this application, there may be one lifting device 210, and the lifting device 210 is provided with multiple air outlets 211, and each second roller 132 has a corresponding air outlet 211. The lifting device 210 may be designed to have a large coverage area, capable of covering the entire roller pressing equipment body 100, so that air outlets 211 can be provided at the position of each second roller 132 to ensure that the electrode films 300 under each second roller 132 can be lifted.

[0045] In another specific embodiment of this application, a lifting device 210 is provided on the lower side of each second roll 132. There are multiple first rolls 131 and second rolls 132, and the first rolls 131 and second rolls 132 are arranged alternately, that is, a first roll 131 is provided between every two second rolls 132, and a second roll 132 is provided between every two first rolls 131.

[0046] When a lifting device 210 is provided on the lower side of each second roll 132, there may be multiple air outlets 211 of each lifting device 210, and in the lifting devices 210 arranged on the lower side of each second roll 132, all air outlets 211 face the same second roll 132 above them.

[0047] Each air outlet 211 of each lifting device 210 is arranged at intervals along the arrangement direction of the rolls 130, that is, arranged in a direction perpendicular to the axial direction of the rolls 130. This arrangement allows each air outlet 211 to blow air onto different positions on the roll surface of the second roll 132, thereby increasing the area covered by the air pressure. Compared to having only one air outlet 211, which would require increasing the width of the air outlet 211 (i.e., the dimension along the arrangement direction of the rolls 130) to increase the air pressure coverage area, this arrangement, while also increasing the air pressure coverage area, inevitably affects the flow velocity of the airflow blown out of the air outlet 211 due to its larger flow area, thus affecting the air pressure acting on the electrode diaphragm 300. In this embodiment, multiple air outlets 211 are provided and arranged at intervals. Without increasing the flow area of ​​each air outlet 211, the air pressure coverage area acting on the electrode diaphragm 300 can be increased, thus pushing the larger area of ​​the electrode diaphragm 300 to adhere to the roller surface of the roll 130.

[0048] Multiple air outlets 211 can provide more uniform and comprehensive lifting force to different parts of the electrode diaphragm 300 hanging from the roll 130. Because the electrode diaphragm 300 has a large area, a single air outlet 211 may not be able to guarantee sufficient and uniform airflow support throughout the diaphragm 300, easily leading to localized sagging or uneven stress and deformation. Multiple air outlets 211 supplying air from different positions effectively avoids this situation, ensuring that the electrode diaphragm 300 remains stable and flat, thus improving production quality.

[0049] The airflow blown out from each air outlet 211 acts on the roller surface of the roll 130 and spreads to both sides along the roller surface of the roll 130. Compared with other lifting methods, it will not damage the electrode diaphragm 300, and the airflow can cover a large area of ​​the electrode diaphragm 300 by relying on the flow of air.

[0050] Furthermore, the number of air outlets 211 can be even. When the number of air outlets 211 is even, each air outlet 211 can be arranged in groups, with each group consisting of two air outlets 211, that is, two air outlets 211 form a group.

[0051] Two air outlets 211 in the same group are symmetrically arranged along the axis of the second roll 132. Taking two groups of air outlets as an example, the airflow from the two middle air outlets 211 (i.e., the middle group of air outlets) can cover the roll surface area between the two air outlets 211; the airflow from the two outer air outlets 211 (the outer group of air outlets) can cover the roll surface area between the adjacent middle group of air outlets. This arrangement can gradually cover the lower side of the roll surface of the roll 130, improving the uniformity of the air pressure acting on the electrode diaphragm 300.

[0052] It should be noted that there may only be two air outlets (e.g., air outlet 211). Figure 5 (The scheme shown). Simulation results show that only two air outlets 211 are needed to ensure a large coverage area on the roll surface of the roll 130, guaranteeing the adhesion between the electrode diaphragm 300 and the roll surface of the roll 130. From an energy-saving perspective, only two air outlets 211 are required. The number of air outlets 211 is not limited to two; it can also be four, six, etc. This embodiment does not limit the specific number of air outlets 211.

[0053] The number of air outlets 211 can also be odd, for example, 2n+1, where n is a positive integer. When the number of air outlets 211 is odd, one air outlet 211 is arranged vertically directly below the axis of the second roll 132, and the other air outlets 211 are arranged in groups of two, with the two air outlets 211 in the same group arranged symmetrically along the axis of the second roll 132. Taking three air outlets 211 as an example, the airflow from the two outer air outlets 211 can cover the roll surface area between them and the adjacent middle air outlet 211. This arrangement can gradually cover the lower side of the roll surface of the roll 130, improving the uniformity of the air pressure acting on the electrode diaphragm 300.

[0054] It should be noted that the number of air outlets 211 is not limited to three, but can also be five, seven, etc. This embodiment does not limit the specific number of air outlets 211.

[0055] The two outermost air outlets 211 determine the air pressure coverage range of the lifting device 210. In a specific embodiment of this application, for ease of understanding, within the plane containing the cross-section of the second roll 132, the intersection of the air outlet direction of one of the two outermost air outlets 211 and the second roll 132 is defined as the first air receiving point, that is, the airflow blown out by this air outlet 211 will act on the first air receiving point. It should be noted that the first air receiving point is not a point in the mathematical sense, but rather represents the intersection of the air outlet direction of the air outlet 211 and the second roll 132.

[0056] The intersection of the airflow direction of the other of the two outermost air outlets 211 and the second roll 132 is defined as the second air receiving point. That is, the airflow blown out by this air outlet 211 will act on the second air receiving point. It should be noted that the second air receiving point is not a point in the mathematical sense, but rather represents the intersection of the airflow direction of the air outlet 211 and the second roll 132.

[0057] Within the plane containing the cross-section of the second roll 132, the air outlets 211 located on opposite sides furthest from the axis of the second roll 132 are the outermost air outlets 211. For ease of understanding, the plane containing the axis of the second roll 132 and the lowest point of the second roll 132 is defined as the reference plane. The air outlets 211 of the lifting device 210 are arranged in a basically symmetrical manner along the reference plane. Opposite sides refer to having air outlets 211 furthest from the reference plane (which can also be understood as the axis of the second roll 132) on both sides of the reference plane.

[0058] like Figure 5 As shown, the line connecting the first wind-receiving point and the axis of the second roll 132 is defined as the first connecting line 211a, and the line connecting the second wind-receiving point and the axis of the second roll 132 is defined as the second connecting line 211b. The included angle α between the first connecting line 211a and the second connecting line 211b is 5° to 60°. For example, α can be 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc. This embodiment does not limit the specific value of α; those skilled in the art can select a value within the range of 5° to 60° based on their needs.

[0059] It should be noted that the included angle α° is the central angle of the air pressure coverage range of the lifting device 210 acting on the roll 130. The larger the included angle α°, the larger the air pressure coverage range of the lifting device 210; the smaller the included angle α°, the smaller the air pressure coverage range of the lifting device 210. In this embodiment, the included angle α° is selected within the range of 5° to 60°. This avoids the problem that the air pressure in the middle area of ​​the lower side of the roll surface of the roll 130 is too low due to the air pressure coverage range of the lifting device 210 being too large, thus affecting the lifting effect; it also avoids the problem that the air pressure coverage range of the lifting device 210 is too small, which cannot meet the requirement of lifting the entire lower side of the roll 130, thus failing to ensure the large-scale adhesion of the electrode diaphragm 300.

[0060] Furthermore, the value range of a° can preferably be 10°~15°. Of course, the arc length of the outer circumference of the second roll 132 corresponding to the angle between the first connecting line 211a and the second connecting line 211b can also be designed to be 15%~18% of the diameter of the second roll 232.

[0061] For example, a° can be 10°, 10.5°, 11°, 11.5°, 12°, 12.5°, 13°, 13.5°, 14°, 14.5°, 15°, etc. This embodiment does not limit the specific value of a°, and those skilled in the art can select it within the range of 10° to 15° based on their needs.

[0062] Furthermore, within the cross-section of the second roll 132, the line connecting the axis of the second roll 132 and the lowest point of the second roll 132 is the third connecting line, and the plane containing the third connecting line and the axis is the reference plane. The angle between the first connecting line 211a and the third connecting line is the first angle, and the angle between the second connecting line 211b and the third connecting line is the second angle. The absolute value of the angle difference between the first angle and the second angle is less than or equal to 30°. That is, in this embodiment, the two outermost air outlets 211 are allowed to be asymmetrical along the third connecting line, but the angle difference between the first angle and the second angle should not be too large, and should be kept within 30°. Of course, the two outermost air outlets 211 can also be symmetrical along the third connecting line, that is, the angle difference between the first angle and the second angle is 0°.

[0063] like Figure 6 As shown, in this embodiment, the angle between the air outlet 211 and the horizontal direction is b°. It should be noted that the arrangement direction of each roll 130 is generally horizontal, meaning the axial direction of the roll 130 is parallel to the horizontal plane. In this embodiment, b° < 90°, meaning the angle between the air outlet 211 and the horizontal direction is acute. This means the airflow from the air outlet 211 blows at an angle towards the roll surface of the roll 130, and the air outlet 211's airflow direction is inclined towards the axis of the roll 130. This arrangement allows the airflow from the air outlet 211 to blow towards the middle area of ​​the lower roll surface of the roll 130. Compared to blowing air vertically upwards or blowing air obliquely upwards along the axis away from the roll 130, the air pressure can be more concentrated on the lowest area of ​​the roll 130, that is, on the area where the electrode diaphragm 300 is most severely detached from the roll surface, thereby improving the lifting effect on the electrode diaphragm 300.

[0064] In this embodiment, the angle b° ranges from 17° to 25°. It should be noted that the included angle b° is the tilt angle of the air outlet 211 in the direction of airflow. With a fixed vertical distance between the lifting device 210 and the roll 130, a larger included angle b° indicates a larger air pressure coverage area for the lifting device 210, and a smaller included angle b° indicates a smaller air pressure coverage area for the lifting device 210. In this embodiment, selecting the included angle b° within the range of 17° to 25° avoids the problem of insufficient air pressure in the middle area of ​​the lower side of the roll surface of the roll 130 due to an excessively large air pressure coverage area for the lifting device 210, thus affecting the lifting effect; it also avoids the problem of insufficient air pressure coverage area for the lifting device 210, which would fail to meet the requirement of full-range lifting of the lower side of the roll 130, resulting in an inability to ensure large-scale adhesion of the electrode diaphragm 300.

[0065] For example, b° can be 17°, 17.5°, 18°, 18.5°, 19°, 19.5°, 20°, 20.5°, 21°, 22°, 23°, 24°, 25°, etc. This embodiment does not limit the specific value of b°, and those skilled in the art can select it within the range of 17° to 25° based on their needs.

[0066] like Figure 5 As shown in a specific embodiment of this application, the minimum distance Lmm between the outlet end of the air outlet 211 and the second roller 132 in the vertical direction is 80mm~100mm. For example, Lmm can be 80mm, 82mm, 85mm, 87mm, 90mm, 93mm, 95mm, 98mm, 100mm, etc. This embodiment does not limit the specific value of Lmm; those skilled in the art can select it within the range of 80mm~100mm based on their needs. Setting this minimum distance Lmm allows for the possibility of human interference; selecting it within the range of 80mm~100mm ensures that the reserved size is convenient for the operator's hand operation.

[0067] It should be noted that the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132 reflects the magnitude of the air pressure exerted by the lifting device 210 on the roll 130. The larger the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132, the smaller the air pressure exerted by the lifting device 210 on the roll 130; conversely, the smaller the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132, the greater the air pressure exerted by the lifting device 210 on the roll 130.

[0068] Furthermore, when b° < 90°, the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132 can also reflect the size of the air pressure coverage range of the lifting device 210. The larger the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132, the smaller the air pressure coverage range of the lifting device 210 on the roll 130; the smaller the minimum distance Lmm between the outlet end of the air outlet 211 and the second roll 132, the larger the air pressure coverage range of the lifting device 210 on the roll 130.

[0069] In this embodiment, selecting Lmm within the range of 80mm to 100mm can take into account both the air pressure coverage and magnitude of the lifting device 210 acting on the roll 130, ensuring that the lifting device 210 outputs an appropriate air pressure coverage and value. This avoids both excessive air pressure that could tear the electrode diaphragm 300 and insufficient air pressure that would prevent the electrode diaphragm 300 from being effectively lifted.

[0070] In one specific embodiment of this application, the air outlet 211 is a strip-shaped air outlet, extending in a direction parallel to the axial direction of the second roller 132. The air outlet's range along the axial direction of the second roller 132 can cover the width of the electrode diaphragm 300 on the second roller 132, where the width of the electrode diaphragm 300 is its dimension along the axial direction of the second roller 132. That is, the length of the air outlet 211 along its extending direction is not less than the width of the electrode diaphragm 300, so that the air blown from the air outlet 211 can act on any position in the width direction of the electrode diaphragm 300, achieving more stable support and avoiding situations where the support position cannot be fully covered, resulting in unbalanced force on the electrode diaphragm 300 and tearing at the airflow boundary.

[0071] Those skilled in the art will understand that the air velocity at the outlet 211 is linearly related to the width of the air duct at the outlet 211 (i.e., the dimension of the outlet 211 along the axial direction of the second roll 132), and the air velocity at the outlet 211 is matched with the film-forming linear velocity of the electrode film 300. When the film-forming linear velocity is greater, the air velocity at the outlet 211 should also be greater.

[0072] In this embodiment, with a film-forming linear velocity of 100 m / min, the outlet air velocity of the air outlet 211 is 1 m / s to 1.6 m / s. It should be noted that when the film-forming linear velocity is other, the outlet air velocity of the air outlet 211 can also be selected within the range of 1 m / s to 1.6 m / s. For example, the outlet air velocity of the air outlet 211 can be 1 m / s, 1.1 m / s, 1.2 m / s, 1.3 m / s, 1.4 m / s, 1.5 m / s, 1.6 m / s, etc. This embodiment does not limit the specific value of the outlet air velocity of the air outlet 211; those skilled in the art can select it within the range of 1 m / s to 1.6 m / s based on their needs.

[0073] like Figure 1 and Figure 2 As shown, in this embodiment, the main body 100 of the roller pressing equipment includes a support frame, the roller 130 is supported on the support frame, and the lifting device 210 can be installed on the support frame via a bracket 140. The support frame may include a base frame 110 and a top frame 120 disposed on the top of the base frame 110. The base frame 110 is used to raise the height of the top frame 120, and the roller 130 can be supported on the top frame 120. The bracket 140 can be fixed to either the base frame 110 or the top frame 120; this application does not limit the fixing position of the bracket 140.

[0074] The bracket 140 can be directly welded to the support frame, or it can be detachably fixed to the support frame using fasteners or other fasteners. This embodiment does not limit the fixing method of the bracket 140.

[0075] like Figure 2As shown, in this embodiment, the bracket 140 is provided with strip-shaped mounting holes, and the lifting device 210 is fixed to the strip-shaped mounting holes by fasteners. At least one strip-shaped mounting hole extends along the axial direction of the roll 130, such as the first strip-shaped mounting hole 141, and / or at least one strip-shaped mounting hole extends in a direction perpendicular to the axial direction of the roll 130, such as the second strip-shaped mounting hole 142. In this embodiment, by providing strip-shaped mounting holes, the fixed position of the lifting device 210 on the bracket 140 can be finely adjusted as needed to adjust the positional relationship between the air outlet 211 and the second roll 132, thereby providing a more stable and precise air pressure acting on the electrode diaphragm 300.

[0076] like Figure 6 As shown, in this embodiment, the lifting device 210 includes an air outlet chamber 213, and an air supply device 230 is connected to the air outlet chamber 213 via an air supply pipe 220. An air outlet 211 is disposed on the air outlet chamber 213. The air outlet chamber 213 may be provided with a pipe interface, and the air supply pipe 220 may be sealed and connected to the pipe interface to achieve communication with the air outlet chamber 213. Alternatively, the air supply pipe 220 may be designed as an integral structure with the air outlet chamber 213. This embodiment does not limit the communication method between the air supply pipe 220 and the air outlet chamber 213.

[0077] The gas supply device 230 supplies gas to the air outlet chamber 213 through the gas supply pipe 220, increasing the air pressure inside the air outlet chamber 213. Under the action of air pressure, the gas inside the air outlet chamber 213 is discharged through the air outlet 211. By adjusting the gas flow rate entering the air outlet chamber 213 through the gas supply pipe 220, the air flow rate at the air outlet 211 can be adjusted, thereby regulating the pressure acting on the electrode diaphragm 300. The gas flow rate entering the air outlet chamber 213 through the gas supply pipe 220 can be adjusted by the gas supply device 230 or by a flow valve installed on the gas supply pipe 220.

[0078] In this embodiment, the air outlet 211 and the air supply pipe 220 are located at opposite ends of the air outlet cavity 213 to facilitate gas flow. Furthermore, the air outlet 211 can be disposed on the air outlet component 212, and the end of the air outlet cavity 213 away from the air supply pipe 220 has an installation port. The air outlet component 212 is sealed and installed in the installation port, and the air outlet 211 communicates with the air outlet cavity 213. That is, in this embodiment, the air outlet 211 is formed on the air outlet component 212, and the air outlet component 212 is then fixed to the air outlet cavity 213. This arrangement facilitates the processing of the air outlet 211. Of course, the air outlet 211 can also be formed directly on the air outlet cavity 213; this embodiment does not limit the formation method of the air outlet 211.

[0079] When the air outlet 211 is formed on the air outlet component 212, the air outlet component 212 can be installed on the mounting port in a detachable manner. The detachable method includes, but is not limited to, fastener fixing, snap-fit ​​fixing, etc. Since the air outlet component 212 is detachably installed on the air outlet cavity 213, it can be replaced as needed. For example, by replacing different air outlet components 212, air outlets 211 of different sizes and tilt angles can be obtained; if the air outlet 211 becomes blocked, the air outlet component 212 can also be removed, and the blocked air outlet 211 can be cleared from the outside of the air outlet cavity 213; of course, if the air outlet 211 becomes blocked, a new air outlet component 212 can be directly replaced.

[0080] As illustrated in this application, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0081] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0082] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0083] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A dry electrode rolling mill, characterized in that, include: The main body (100) of the rolling equipment includes multiple rolls (130) for compacting and thinning electrode films (300). Among the rolls (130), the roll (130) that cooperates with the electrode film (300) on the upper side of the roll surface is the first roll (131), and the roll (130) that cooperates with the electrode film (300) on the lower side of the roll surface is the second roll (132). The wind pressure lifting system (200) includes a lifting device (210) and an air supply device (230) for supplying air to the lifting device (210). The lifting device (210) is disposed on the underside of the roll (130) and includes an air outlet (211) for blowing air toward the electrode diaphragm (300) on the second roll (132). Within the cross-section of the second roll (132), the horizontal distance between the air outlet (211) and the lowest point of the second roll (132) is L1mm, where L1mm is 43mm~65mm. The air outlet is the intersection of the air outlet (211) and the outer contour of the second roll (132).

2. The dry electrode rolling equipment as described in claim 1, characterized in that, There is one lifting device (210), and the lifting device (210) is provided with multiple air outlets (211), and each of the second rollers (132) corresponds to an air outlet (211).

3. The dry electrode rolling equipment as described in claim 1, characterized in that, Each of the second rolls (132) is provided with a lifting device (210) on its lower side. There are multiple first rolls (131) and second rolls (132), and the first rolls (131) and second rolls (132) are arranged alternately.

4. The dry electrode rolling equipment as described in claim 3, characterized in that, The lifting device (210) has multiple air outlets (211), and in each lifting device (210) arranged below the second roller (132), all the air outlets (211) face the same second roller (132) above them.

5. The dry electrode rolling equipment as described in claim 4, characterized in that, The number of air outlets (211) is even.

6. The dry electrode rolling equipment as described in claim 5, characterized in that, Each of the air outlets (211) is arranged in a group, and each group has two air outlets (211). The two air outlets (211) in the same group are arranged symmetrically along the axis of the second roller (132).

7. The dry electrode rolling equipment as described in claim 5, characterized in that, There are two air outlets (211).

8. The dry electrode rolling equipment as described in claim 3, characterized in that, The number of air outlets (211) is odd.

9. The dry electrode rolling equipment as described in claim 8, characterized in that, The number of air outlets (211) is 2n+1, where n is a positive integer; One of the air outlets (211) is arranged vertically directly below the axis of the second roll (132), and the other air outlets (211) are arranged in groups, with two air outlets (211) in each group. The two air outlets (211) in the same group are arranged symmetrically along the axis of the second roll (132).

10. The dry electrode rolling equipment as described in any one of claims 4-9, characterized in that, In the plane containing the cross-section of the second roll (132), the intersection of the air outlet (211) of one of the two outermost air outlets (211) with the second roll (132) is the first air receiving point, and the intersection of the air outlet (211) of the other air outlet (211) with the second roll (132) is the second air receiving point. The line connecting the first air receiving point and the axis of the second roll (132) is the first connecting line (211a), and the line connecting the second air receiving point and the axis of the second roll (132) is the second connecting line (211b). In the plane containing the cross-section of the second roll (132), the air outlets (211) located on opposite sides furthest from the axis of the second roll (132) are the outermost air outlets (211). The angle α between the first line (211a) and the second line (211b) is 5° to 60°.

11. The dry electrode rolling equipment as described in claim 10, characterized in that, Within the cross-section of the second roll (132), the line connecting the axis of the second roll (132) and the lowest point of the second roll (132) is the third connecting line; The angle between the first line (211a) and the third line is the first angle, and the angle between the second line (211b) and the third line is the second angle. The absolute value of the angle difference between the first angle and the second angle is less than or equal to 30°.

12. The dry electrode rolling equipment as described in claim 10, characterized in that, a° is 10°~15°.

13. The dry electrode rolling equipment as described in any one of claims 4-9, characterized in that, The air outlet (211) has an air outlet direction with an angle of b° with the horizontal direction, b° < 90°, and the air outlet (211) is inclined toward the axis of the roller (130).

14. The dry electrode rolling equipment as described in claim 13, characterized in that, The angle range of b° is 17°~25°.

15. The dry electrode rolling equipment as described in any one of claims 1-9, characterized in that, The air outlet (211) is a strip-shaped air outlet, and the strip-shaped air outlet extends in a direction parallel to the axial direction of the second roll (132). The air outlet range of the strip-shaped air outlet can cover the width of the electrode diaphragm (300) on the second roll (132). The width of the electrode diaphragm (300) is the dimension along the axial direction of the second roll (132).

16. The dry electrode rolling equipment as described in any one of claims 1-9, characterized in that, The air outlet (211) has an air velocity of 1 m / s to 1.6 m / s.

17. The dry electrode rolling equipment as described in any one of claims 1-9, characterized in that, In the vertical direction, the minimum distance Lmm between the outlet end of the air outlet (211) and the second roll (132) is 80mm~100mm.

18. The dry electrode rolling equipment as described in any one of claims 1-9, characterized in that, The main body (100) of the roller pressing equipment includes a support frame, the roller (130) is supported on the support frame, and the lifting device (210) is installed on the support frame through a bracket (140).

19. The dry electrode rolling equipment as described in claim 18, characterized in that, The bracket (140) is provided with a strip-shaped mounting hole, and the lifting device (210) is fixed to the strip-shaped mounting hole by fasteners; At least one of the strip mounting holes extends along the axial direction of the roll (130), and / or at least one of the strip mounting holes extends in a direction perpendicular to the axial direction of the roll (130).

20. The dry electrode rolling equipment as described in any one of claims 1-9, characterized in that, The lifting device (210) includes an air outlet cavity (213), and the air supply device (230) is connected to the air outlet cavity (213) through an air supply pipeline (220). The air outlet (211) is located on the air outlet cavity (213).

21. The dry electrode rolling equipment as described in claim 20, characterized in that, The air outlet (211) and the air supply pipe (220) are located at opposite ends of the air outlet cavity (213).

22. The dry electrode rolling equipment as described in claim 20, characterized in that, The air outlet (211) is disposed on the air outlet component (212), and the air outlet cavity (213) has an installation port at one end away from the air supply pipeline (220). The air outlet component (212) is sealed and installed in the installation port, and the air outlet (211) is connected to the air outlet cavity (213).

23. The dry electrode rolling equipment as described in claim 22, characterized in that, The air outlet component (212) is detachably installed at the mounting port.

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