Thick electrode coating device for secondary batteries

Abstract

To provide a thick electrode coating apparatus for secondary batteries that can effectively improve coating capacity and coating quality. [Solution] The thick electrode coating apparatus for secondary batteries includes a mounting frame 1, a circulating transfer pump 3, a material transfer pump 4, a filtration device 5, a supply transfer device 6, a supply pipe 7, and a circulating pipe 8. Both the circulating transfer pump 3 and the material transfer pump 4 are fixed to the upper rear end of the mounting frame 1, and both the filtration device 5 and the supply transfer device 6 are fixed to the upper middle end of the mounting frame 1. The filtration device 5 is provided between the circulating transfer pump 3 and the supply transfer device 6, and the circulating transfer pump 3, the filtration device 5, and the supply transfer device 6 are sequentially connected in series via the supply pipe 7. A storage device 2 is provided at the rear of the mounting frame 1, and the output terminal of the storage device 2 is connected in series to the material transfer pump 4 via the circulating pipe 8. The input terminal of the circulating transfer pump 3 is connected to the input terminal of the storage device 2, and a coating device 9 slides into the upper left end of the mounting frame 1.

Description

Technical Field

[0001] This application relates to the electrode processing technology of lithium batteries, and particularly to a thick electrode coating device for secondary batteries.

Background Art

[0002] During the manufacture of secondary batteries, the main purpose of the previous process is to manufacture battery pole pieces (taking the case of manufacturing lithium-ion batteries as an example, the same hereinafter), and mainly includes a stirring process, a coating process, and a roller pressing process. Among these, the coating process is to apply battery slurry (hereinafter referred to as slurry) to the surface of a battery current collector (hereinafter referred to as a substrate), and form a pole plate after drying.

[0003] As is well known, the current situation of lithium-ion batteries is that the energy density is low and the cost is high. Therefore, all battery factories are pursuing to increase the energy density and reduce the cost. By applying a thicker slurry on a substrate of the same thickness to obtain a higher areal density, the proportion of auxiliary materials such as the substrate and the separator occupying the battery can be effectively reduced, and furthermore, the energy density of the battery can be significantly increased and the cost of the battery can be reduced. All battery factories aim to be able to coat thick electrodes and pole pieces with a high areal density.

[0004] A challenge in coating thick electrodes is the inability to ensure uniformity of the coated electrode thickness. Currently, when commercially available electrodes are coated using ordinary extrusion or displacement coating heads, the viscosity of the slurry suitable for the coating window is low, with the coating viscosity window for mass production lines being approximately 1500-12000 CP. When thick electrodes are coated with low-viscosity slurry, the slurry's fluidity is good, and when the wet film thickness is large, the effects of pressure balance during internal conveyance in the head, the effect of gravity on the pole piece after coating, and the effect of uniformity of hot air during baking make it difficult for the slurry to fix its shape on the substrate surface, resulting in poor thickness uniformity and failing to meet the usage requirements. Using a two-layer coating head can solve the problem of internal conveyance pressure balance, allowing for thicker coating of the wet film pole piece, but it cannot solve the problem of thickness uniformity caused by external forces such as gravity and uniformity of airflow acting on the fluid slurry. In addition, the internal resistance of the two-layer wet film interface coated by a two-layer coating head is large, resulting in poor pole piece performance.

[0005] Therefore, an effective method for applying thick electrodes in one go is to increase the viscosity of the slurry.

[0006] However, after the viscosity of the slurry is increased, the slurry's fluidity deteriorates, it loses its leveling ability, and its rheological properties become more pronounced. As a result, current commercially available displacement heads and ordinary extrusion dispensing heads cannot dispense high-viscosity slurries.

[0007] For the reasons stated above, the application of thick electrodes with high surface density and the application of high-viscosity slurries are challenges for the new energy industry. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The primary objective of this application is to provide a device for coating thick electrodes for secondary batteries that effectively solves the problems in the background art. [Means for solving the problem]

[0009] To achieve the aforementioned objectives, the present invention provides the following technical embodiments.

[0010] The thick electrode coating apparatus for secondary batteries includes a mounting frame, a circulating transfer pump, a material transfer pump, a filtration device, a supply transfer device, a supply pipe 1, and a circulating pipe 1. The circulating transfer pump and the material transfer pump are both fixed to the upper rear end of the mounting frame, the filtration device and the supply transfer device are both fixed to the upper middle end of the mounting frame, the filtration device is provided between the circulating transfer pump and the supply transfer device, and the circulating transfer pump, the filtration device, and the supply transfer device are sequentially connected in series via the supply pipe 1.

[0011] A storage device is provided at the rear of the mounting frame, and a circulation pipe is connected in series between the output terminal of the storage device and the material transport pump, and the input terminal of the circulation transport pump is connected to the input terminal of the storage device, and a coating device is slidably mounted on the upper left part of the mounting frame.

[0012] Preferably, the storage device includes a storage tank, with a raw material return pipe and a supply pipe attached symmetrically to the front and rear of the storage tank, a discharge pipe attached to the bottom of the storage tank, a motor attached to the middle of the upper wall of the storage tank, a connecting rod attached to the output end of the motor via a coupling, a stirring paddle attached to the lower end of the connecting rod, the input end of the material transport pump connected to the discharge pipe via a circulation pipe, and the output end of the circulating transport pump connected to the raw material return pipe via a supply pipe.

[0013] Preferably, the coating apparatus includes a plurality of slide rails attached to the upper front end of a mounting frame, fasteners slide on the surface of the plurality of slide rails, a base 2 is commonly fixed to the upper ends of the plurality of fasteners, a base 1 is provided on the upper end of the base 2, a plurality of support frames 1 are fixed to the rear of the base 1, a connecting plate is commonly fixed to the tip of the plurality of support frames 1, a coating mechanism is fixed to the upper end of the base 1, and a plurality of coating head roller attachment drivers attached to the upper end of the mounting frame are provided on the rear end of the base 2.

[0014] Preferably, the coating mechanism includes a coating valve seat 1 fixed to the upper end of the horizontal portion of a base 1 and a plurality of coating valve drivers attached to the front of the base 1, a movable groove 1 is provided at the front of the upper end of the coating valve seat 1, an arc-shaped recess is provided at the rear of the upper end of the coating valve seat 1, a plurality of coating valves 1 slide in the internal cavity of the movable groove 1, a coating valve seat 2 is fixed to the middle of the tip of the vertical portion of the base 1, a baffle slides in the middle of the upper end of the coating valve seat 2, a plurality of coating valves 2 are provided at the tip of the coating valve 4, a coating valve 3 slides at the upper end of the coating valve 4 and at the upper ends of the plurality of coating valves 2, baffles are attached to the left and right ends of the tip of the coating valve 4, and the two baffles are located to the left of the leftmost coating valve 2 and to the right of the rightmost coating valve 2, respectively.

[0015] A circulation pipe 3 is fixed to the upper end of each of the multiple coating valves 2.

[0016] Multiple slide grooves corresponding to the same-side circulation pipes 3 are provided at the upper end of the coating valve 3, and each of the multiple circulation pipes 3 is located within a slide groove.

[0017] The coating valves 2 and 3, which are arranged along the direction of movement of the substrate, are multiple in number.

[0018] The input end of the aforementioned circulation pipe 1 is attached to the middle of the left and right ends of the base 1, and both are connected to the internal cavity of the arc-shaped recess.

[0019] Preferably, a plurality of coating valve 3 drivers, a plurality of coating valve 4 drivers, and a plurality of coating valve 2 drivers are attached to the tip of the connecting plate, the output end piston rods of the plurality of coating valve 4 drivers pass through the vertical portion of the base 1 and are all connected to the rear end of the coating valve 4, the output end piston rods of the plurality of coating valve 2 drivers pass through the vertical portion of the base 1 and are all connected to the coating valve 2 driver on the same side, the plurality of coating valve 4 drivers are arranged symmetrically to the left and right of the plurality of coating valve 2 drivers, and the output end piston rods of the plurality of coating valve 3 drivers pass through the vertical portion of the base 1 and are all connected to the rear end of the coating valve 3.

[0020] Preferably, the lower part of the outer surface of each of the multiple coating valves 2 facing the back roller is provided in an arc shape, an arc-shaped groove is provided on the upper part of the outer surface of each coating valve 2 facing the back roller, a pressure sensor 2 is attached to the middle of the inner surface of the arc-shaped groove, and a recirculation hole is provided at the front of the inner surface of the arc-shaped groove, which leads to the internal cavity of the circulation pipe 3 on the same side.

[0021] Preferably, the lower tip of the coating valve seat 2 is rounded, and the pressure sensor 1 is also attached.

[0022] Preferably, the lower tip of the coating valve 3 has an arc-shaped, flat, irregularly shaped, or adjustable structure.

[0023] Preferably, a lateral displacement drive device for the coating head is mounted between the base 2 and the base 1. [Effects of the Invention]

[0024] This application has the following beneficial effects compared to the prior art.

[0025] In this application, in application valve two, it is divided into a plurality of widths in the lateral width direction so as to correspond to the width allocation of application valve one. The slurry exiting from the outlet of application valve one has different slurry thicknesses when applied in areas with large and small flow rates. At this time, the gaps between the plurality of application valves two and the substrate in the lateral direction are adjusted, and the slurry flow rate in the lateral direction is balanced again to make the slurry flow rate in the lateral direction the same, thereby further improving the coating quality. At the same time, by mutually coordinating application valve one, application valve two, application valve three, and application valve four, the diffusion rate of the high-viscosity slurry to application valve one, application valve two, and application valve three is increased, and the uniformity of the slurry distribution is enhanced. Also, by increasing the application valves that perform the same function as application valve two or application valve three, the balance of the slurry flow rate in the lateral direction can be further suppressed.

[0026] In this application, pressure sensor one and pressure sensor two for measuring the pressure of the slurry are installed in coating cavity two and coating cavity three to keep the pressure of the slurry in coating cavity two and coating cavity three constant during coating. Due to the pressure, it becomes easier for the slurry to flow into the gaps between coating cavity two, coating cavity three and the substrate, and the slurry adheres perfectly to the substrate, further improving the coating quality.

[0027] [[ID=第八条]]In this application, the unused slurry can be returned to the internal cavity of the storage tank again through circulation pipe three, circulation pipe one, etc. By fully using this slurry, the utilization rate of the slurry can be increased, waste can be reduced, and the coating cost can be further reduced.

Brief Description of the Drawings

[0028] [Figure 1] It is the overall configuration diagram of this application. [Figure 2] It is the overall configuration diagram of another perspective of this application. [Figure 3] It is the enlarged view of location A in Figure 1 of this application. [Figure 4] It is the partial configuration diagram of the coating mechanism of this application. [Figure 5] It is the overall configuration diagram of the coating mechanism of this application. [Figure 6] It is the enlarged view of location B in Figure 5 of this application. [Figure 7] This is a partial front view of the present application. [Figure 8] This is a partial schematic diagram of one of the coating apparatus replacement embodiments of this application. [Figure 9] This is a partial schematic diagram of one of the coating apparatus replacement embodiments of this application. [Modes for carrying out the invention]

[0029] To facilitate understanding of the technical means, creative features, objectives, and effects realized in this application, the specific mode of implementation will be further described below.

[0030] As shown in Figures 1 and 2, in Embodiment 1, the thick electrode coating apparatus for secondary batteries includes a mounting frame 1, a circulating transfer pump 3, a material transfer pump 4, a filtration device 5, a supply transfer device 6, a supply pipe 7, and a circulating pipe 8. The circulating transfer pump 3 and the material transfer pump 4 are both fixed to the upper rear end of the mounting frame 1, the filtration device 5 and the supply transfer device 6 are both fixed to the upper middle end of the mounting frame 1, the filtration device 5 is provided between the circulating transfer pump 3 and the supply transfer device 6, and the circulating transfer pump 3, the filtration device 5, and the supply transfer device 6 are sequentially connected in series via the supply pipe 7.

[0031] The above-mentioned circulating transfer pump 3, material transfer pump 4, filtration device 5, and supply transfer device 6 are all based on conventional general designs. In the embodiment, the filtration device 5 can be an Isei EJS series high-viscosity slurry self-cleaning filter such as the EJS-N type or EJS-W type.

[0032] In this embodiment, the supply conveying device 6 can convey raw materials using a spiral conveyor.

[0033] As described above, the slurry is extracted from the storage device 2 by the circulating transfer pump 3 and sequentially passes through the supply pipe 7, filtration device 5, supply transfer device 6, coating device 9, circulation pipe 8 and material transfer pump 4, before finally returning to the storage device 2.

[0034] In more detail, during implementation, a storage device 2 is provided at the rear of the mounting frame 1 to agitate the slurry and reduce the number of air bubbles in the slurry. The output terminal of the storage device 2 and the material transport pump 4 are connected in series via a circulation pipe 8, and the output terminal of the circulating transport pump 3 is connected to the input terminal of the storage device 2. A coating device 9 slides onto the upper left part of the mounting frame 1.

[0035] The storage device 2 includes a storage tank 21, with a raw material return pipe and a supply pipe attached symmetrically to the front and rear of the storage tank 21, a discharge pipe attached to the bottom of the storage tank 21, a motor 24 attached to the middle of the upper wall of the storage tank 21, a connecting rod attached to the output end of the motor 24 via a coupling, a stirring paddle 22 attached to the lower end of the connecting rod, the input end of the material transport pump 4 connected to the discharge pipe via a circulation pipe 8, the output end of the circulating transport pump 3 connected to the raw material return pipe via a supply pipe 7, and a valve attached to the outer surface of the circulation pipe 8.

[0036] As described above, raw materials are supplied to the internal cavity of the storage tank 21 via a supply pipe, and the slurry in the internal cavity of the storage tank 21 can be extracted through the coordinated operation of the circulating transfer pump 3, the supply pipe 7, and the discharge pipe.

[0037] During the implementation, after the slurry is injected into the internal cavity of the storage tank 21, the motor 24 is turned on, and with the cooperation of the connecting rod, the stirring paddle 22 is driven to continuously stir the slurry.

[0038] Any extracted slurry that has not been used is collected and recycled through the material transport pump 4 and into the internal cavity of the storage tank 21, reducing raw material waste. When not applying the slurry, all application valves 964 are turned off, and the valves of the circulation piping 8 are opened, allowing the slurry to continue circulating between the storage tank 21 and the arc-shaped recess 965 of the application cavity to prevent the slurry from settling.

[0039] The filtration device 5 can filter out impurities and particles from the slurry. The supply and conveying device 6 conveys the filtered slurry to the coating cavity 1 via piping.

[0040] In Example 2, based on Example 1, the material sent out by the pump is applied to the coating substrate 11 via the coating device 9.

[0041] More specifically, in order to achieve the above objective, as shown in Figures 4-7, the coating device 9 includes a plurality of slide rails 92 attached to the upper front end of the mounting frame 1, fasteners 91 slide on the surface of all of the plurality of slide rails 92, a base 2 93 is commonly fixed to the upper ends of the plurality of fasteners 91, a base 1 94 is provided on the upper end of the base 2 93, a plurality of support frames 1 95 are fixed to the rear of the base 1 94, a connecting plate is commonly fixed to the tip of the plurality of support frames 1 95, a coating mechanism 96 is fixed to the upper end of the base 1 94, and a plurality of coating head roller attachment drivers 97 attached to the upper end of the mounting frame 1 are provided on the rear end of the base 2 93.

[0042] The installed fasteners 91 and slide rails 92 work together so that the bases 2 93, 1 94, and multiple support frames 1 95 can all slide forward at the tip of the mounting frame 1 when driven by the coating head roller attachment driver 97.

[0043] The system can move in conjunction with the coating mechanism 96, etc., while simultaneously supplying and returning raw materials. In this embodiment, the middle sections of both the supply pipe 7 and the circulation pipe 8 are high-pressure hoses, and the front sections of the supply pipe 7 and circulation pipe 8 can ensure the stability of the rear sections during movement, thereby ensuring the normal transport of the slurry.

[0044] The support frame 95 described above can drive the mechanism to support the power sources inside the coating mechanism 96, such as the coating valve driver 373, coating valve driver 4974, and coating valve driver 2975.

[0045] The coating mechanism 96 includes a coating valve seat 962 fixed to the upper end of the horizontal portion of the base 94 and a plurality of coating valve drivers 961 attached to the front of the base 94. A movable groove 963 is provided at the front of the upper end of the coating valve seat 962, and an arc-shaped recess 965 is provided at the rear of the upper end of the coating valve seat 962. Multiple coating valves 964 slide within the internal cavity of the movable groove 963, and a coating valve seat 2 966 is fixed to the middle of the tip of the vertical portion of the base 94. A baffle 976 slides in the middle of the upper end of 966, multiple coating valves 2 968 are provided at the tip of coating valve 4 967, coating valves 3 969 slide in at the upper end of both coating valve 4 967 and the upper end of the multiple coating valves 2 968, baffles 976 are attached to both the left and right ends of the tip of coating valve 4 967, and the two baffles 976 are located to the left of the leftmost coating valve 2 968 and to the right of the rightmost coating valve 2 968, respectively.

[0046] The above-mentioned multiple coating valves 964 are divided into two parts, front and back, between the coating valve seat 966 and the coating valve seat 962, and these are defined as coating cavity 2 and coating cavity 1, respectively.

[0047] An arc-shaped groove 9683 is provided on the outer surface of the coating valve 2 968, extending towards the upper part on the back roller 10 side.

[0048] The cavity between the internal cavity of the arc-shaped groove 9683 and the outer surface of the coated substrate 11 is defined as the coated cavity 3.

[0049] In the lateral direction, the coating cavity 1 has a width close to the coating width, and the slurry spreads out in the coating cavity 1 as shown in the lateral direction, enters the coating cavity 2 via the coating valve 1 964, and the coating valve 1 964 has the same width as the coating cavity, and is arranged in a series of blocks along the lateral direction at the coating valve 1 964, and by adjusting the gap between the coating valve 1 964 and the coating valve seat 2 966, the uniformity of the slurry flow from the coating valve 1 to the coating cavity 2 along the lateral direction is initially controlled.

[0050] However, when viewed from the side, it is unavoidable that there is a difference in the slurry flow rate from coating cavity 1 to coating cavity 2. When not applying, all coating valves 1964 are turned off, and the valves of the circulation piping 18 are opened to allow the slurry to continue circulating between the storage tank 21 and coating valve 1, thereby preventing the slurry from settling.

[0051] A circulation pipe 3 972 is fixed to the upper end of each of the multiple application valves 2 968.

[0052] Multiple circulation pipes 3972 are all connected to circulation pipe 18, and simultaneously recirculate used slurry.

[0053] Multiple slide grooves 971 corresponding to the same-side circulation pipes 972 are provided at the upper end of the coating valve 969, and each of the multiple circulation pipes 972 is located within a slide groove 971.

[0054] During operation, the horizontal position of the coating valve 3 969 changes, causing relative sliding between the coating valve 2 968 and the coating valve 3 969. As excess slurry is discharged normally from the return hole 9681 through the circulation pipe 3 972, the circulation pipe 3 972 moves in sync with the coating valve 2 968. The slide groove 971 is provided to prevent the coating valve 3 969 from compressing the circulation pipe 3 972 during movement, in order to ensure the integrity of the circulation pipe 3 972.

[0055] Similarly, high-strength hoses are used within multiple circulating pipes 3972 to extend the movement path of the circulating pipes 3972.

[0056] There are multiple coating valves 2 968 and 3 969, which are arranged along the direction of substrate movement.

[0057] The input end of the circulation pipe 8 is attached to the left and right middle ends of the base 94, both of which lead to the internal cavity of the arc-shaped recess 965. When there is excess slurry in the coating cavity 1 or when the coating valve 964 is closed, the slurry can be returned to the internal cavity of the storage tank 21 via the circulation pipe 8.

[0058] Furthermore, as shown in Figures 4 and 6, in this embodiment, a plurality of coating valve 3 drivers 973, a plurality of coating valve 4 drivers 974, and a plurality of coating valve 2 drivers 975 are attached to the tip of the connecting plate, the output end piston rods of the plurality of coating valve 4 drivers 974 pass through the vertical portion of the base 1 94 and are all connected to the rear end of the coating valve 4 967, the output end piston rods of the plurality of coating valve 2 drivers 975 pass through the vertical portion of the base 1 94 and are all connected to the coating valve 2 driver 968 on the same side, the plurality of coating valve 4 drivers 974 are arranged symmetrically to the left and right of the plurality of coating valve 2 drivers 975, and the output end piston rods of the plurality of coating valve 3 drivers 973 pass through the vertical portion of the base 1 94 and are all connected to the rear end of the coating valve 3 969.

[0059] In the above configuration, the multiple application valve 3 drivers 973, the multiple application valve 4 drivers 974, and the multiple application valve 2 drivers 975 can move the application valve 3 969, the application valve 4 967, and the application valve 2 968 to the left and right, respectively.

[0060] However, when multiple coating valve drivers 4 974 start operating, multiple coating valve drivers 3 973 need to move synchronously, and after coating valve 4 967 moves forward to a predetermined position, multiple coating valves 2 968 may continue to move forward independently.

[0061] The lower part of the outer surface of the multiple coating valves 968 facing the back roller 10 is provided in an arc shape, and further, the shape formed by the bending of the coating substrate 11 on the outer surface of the back roller 10 is brought into close contact, thereby enhancing the coating effect on the slurry. A pressure sensor 9682 is attached to the middle of the inner surface of the arc-shaped groove 9683, and a recirculation hole 9681 is provided at the front of the inner surface of the arc-shaped groove 9683, which leads to the internal cavity of the circulation pipe 972 on the same side.

[0062] The lower tip of the coating valve seat 966 is rounded, and a pressure sensor 9661 is also attached to it.

[0063] The lower tip of the coating valve 3969 has an arc-shaped, flat, irregularly shaped, or adjustable structure. Furthermore, the outer surface of the back roller 10 brings the shape formed by bending the coating substrate 11 into close contact, enhancing the coating effect on the slurry.

[0064] In the above-described process, the substrate bypasses the back roller 10 and moves in conjunction with the rotation of the back roller 10, the coating state stabilizes, and once the slurry fills the coating cavity 2, the substrate is coated with slurry.

[0065] In order to perfectly adhere the slurry to the substrate and to solve the foil leakage problem during the coating process, in this embodiment, as shown in Figure 4, the lower tip of the coating valve seat 966 is rounded and multiple pressure sensors 9661 are attached.

[0066] The pressure sensor 9661 feeds back the pressure of the slurry in the coating cavity 2 to the electrical control system, which then performs PID adjustments according to the actual pressure and the set pressure to control the slurry flow rate that the supply conveying device 6 delivers to the coating cavity 1, thereby stabilizing the pressure in the coating cavity 2 within the system's set pressure range.

[0067] The back roller 10 carries the coating substrate 11, and the coating substrate 11 carries the slurry adhering to the surface of the coating substrate 11 to the coating cavity 3. This corresponds to an increase in the force that continues to transport the slurry inside the die head, thus solving the problem of excessive transport pressure when coating high-viscosity slurries.

[0068] The coating substrate 11 carries the slurry and moves it from the coating cavity 2 to the coating cavity 3 via the coating valve 2 968. As shown in Figure 7, multiple coating valves 4 967 are arranged in parallel and tightly to match a predetermined coating width.

[0069] The coating valve 2 968 may be supported by the coating valve 4 967, and moves in the direction of the back roller 10 by driving the coating valve 1 964 and the arc-shaped recess 965 in order to adjust the gap between the coating valve 2 968 and the substrate.

[0070] During application, the slurry passes through the gap between the application valve 968 and the substrate, controlling different gaps laterally at the same application speed, and thus uniformly controlling the flow rate distributed laterally.

[0071] When the slurry passes through the coating valve 964, the lateral flow velocity of the slurry differs, and due to the rheological properties of the slurry, it can be seen that the lateral flow rate distribution of the slurry differs. When the slurry passes through the gap between the coating valve 968 and the substrate, the appropriate gap is adjusted so that the lateral flow of the slurry passes through the coating valve 968 and arrives at the coating cavity 3, and the flow rate trend of the slurry is consistent.

[0072] In this embodiment, four baffles 976 are provided, and the four baffles 976 are attached to both sides of the coating cavity two and the coating cavity three, respectively. When viewed from the side, the width of the slurry on the coating substrate 11 is controlled by the baffles 976 so that the slurry is limited to a predetermined coating width range.

[0073] When a high-viscosity slurry of the same viscosity arrives at the coating cavity 3, it can balance the lateral pressure within the coating cavity 3.

[0074] In this embodiment, a valve is similarly installed between the circulation pipe 3972 and the circulation pipe 18.

[0075] With the valve in the circulation piping 3972 turned off, the operation of the coating valve 4 driver 974 and the coating valve 2 driver 975 is controlled to drive and move the coating valve 4 driver 967 and the coating valve 2 driver 968, and by appropriately adjusting the gap between the coating valve 4 driver 967 and the coating substrate 11, a uniform slurry flow rate effect can be obtained.

[0076] Under the closed-loop control of the control system, the pressure in the coating cavity 3 can be stabilized within a set range. If the local lateral pressure in the coating cavity 3 is detected to be too high and adjusting the gap would affect the uniformity effect of the slurry, it is necessary to adjust the degree of opening of the upper valve of the circulation pipe 3 972 at the corresponding location to balance the pressure of the slurry in the coating cavity 3.

[0077] The high-viscosity slurry undergoes flow rate uniformization and pressure stabilization treatments, and then passes through the gap between the coating valve 3 969 and the coating substrate 11 to form a stable pole piece that reaches a predetermined thickness.

[0078] Due to the low flow characteristics of high-viscosity slurry, this coating device enables stable coating of thick pole pieces.

[0079] In this embodiment, the coating valve driver 4974, coating driver 2975, coating head roller attachment driver 97, coating valve driver 3973, and coating valve driver 1961 can use either an electric cylinder, a cylinder, or a hydraulic cylinder during the implementation process, as long as the resulting thrust meets the production demands.

[0080] A lateral displacement drive device for the coating head is mounted between base 293 and base 194.

[0081] The above-described lateral drive device is a conventional design of the prior art, and is composed of a concave fixed substrate, a screw rod, and a servo motor. Of these, the base 1 94 is screw-connected to the screw rod and slides to the concave fixed substrate, the concave fixed substrate is attached to the upper end of the base 2 93, the screw rod is rotatably connected to the fixed substrate, and the servo motor is installed on the side of the concave fixed substrate to rotate the screw rod, allowing the coating mechanism 96 and the like to move laterally.

[0082] In Embodiment 3, as shown in Figure 8, as a replacement form 1 of the coating device 9, this embodiment modifies the shape of the arc-shaped recess 965 and adds a movable groove 2 981 and a screw 983 based on Embodiments 1 and 2, but the mounting method and mounting position of the remaining mechanism are the same as in Embodiments 1 and 2.

[0083] Similarly, a movable groove 2 981 is provided on the front upper part of the coating valve 3 969, and multiple screws 983 are rotatably connected at equal intervals to the internal cavity of the movable groove 2 981 on the side closer to the back roller 10. The multiple screws 983 extend to the outside, penetrating the internal cavity of the movable groove 2 981 on the side away from the back roller 10, and are rotatably connected to the side of the coating valve 3 969 away from the back roller 10.

[0084] During the implementation process, by rotating the screw 983 in the forward or reverse direction, the angle of the coating valve 969 on the side facing the coating substrate 11 can be changed, and the linearity of the slurry relative to the coating substrate 11 can be corrected, thereby improving the coating quality.

[0085] In Embodiment 4, as shown in Figure 9, as a replacement configuration 2 of the coating apparatus 9, in this embodiment the mounting positions of the coating valve 1 driver 961 and coating valve 1 964 are changed from the original vertical direction to the horizontal direction, and the coating valve 1 driver 961 and coating valve 1 964 are on the same horizontal plane and located below the coating valve 4 driver 974. Based on Embodiments 1 and 2, a movable groove 3 984, coating valve 5 985, coating valve 5 driver 986, and support frame 2 987 are added, and the mounting method and mounting position of the remaining mechanism are the same as in Embodiments 1 and 2.

[0086] As can be seen in Figure 9, the side of the coating valve 964 closer to the coating substrate 11 is curved, which improves the smoothness of the slurry flow.

[0087] Multiple application valve drivers 961 may be mounted on the support frame 95.

[0088] More specifically, a movable groove 3 984 is provided at the tip of the coating valve 3 969, and multiple coating valves 5 985, arranged laterally, slide within the internal cavity of the movable groove 3 984. Each of the multiple coating valves 5 985 has a coating valve driver 986 attached to the central part of one side away from the coating substrate 11. A support frame 2 987 is commonly fixed between the rear ends of the multiple coating valve drivers 986 and the coating valve 3 969.

[0089] In this embodiment, the dispensing valve driver 986 may use an electric cylinder, a cylinder, or a hydraulic cylinder in the process, as long as the resulting thrust meets the production demand.

[0090] In this embodiment, multiple coating valves 5 985 are added, and by adjusting the extension length of each coating valve 5 985 by driving the coating valve 5 driver 986, the linearity of the slurry relative to the coating substrate 11 can be corrected, thereby improving the coating quality.

[0091] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art will understand that this application is not limited to the embodiments described above, and that the embodiments and specification described above are for illustrative purposes only, and that various modifications and improvements have been made without departing from the spirit and scope of this application, and that these are within the scope of the application for which protection is sought. The scope of the claims of this application is defined by the appended claims and their equivalents. [Explanation of Symbols]

[0092] 1. Mounting frame, 2. Storage device, 21. Storage tank, 22. Agitation paddle, 24. Motor, 3. Circulating transfer pump, 4. Material transfer pump, 5. Filtration device, 6. Supply transfer device, 7. Supply piping 1, 8. Circulation piping 1, 9. Coating device, 91. Fastener, 92. Slide rail, 93. Base 2, 94. Base 1, 95. Support frame 1, 96. Coating mechanism, 961. Coating valve driver, 962. Coating valve seat 1, 963. Movable groove 1, 964. Coating valve 1, 965. Arc-shaped recess, 966. Coating valve seat 2, 9661. Pressure sensor 1, 967 , coating valve 4, 968, coating valve 2, 9681, return hole, 9682, pressure sensor 2, 9683, arc-shaped groove, 969, coating valve 3, 971, slide groove, 972, circulation piping 3, 973, coating valve 3 driver, 974, coating valve 4 driver, 975, coating valve 2 driver, 976, baffle, 97, coating head roller attachment driver, 981, movable groove 2, 983, screw, 984, movable groove 3, 985, coating valve 5, 986, coating valve 5 driver, 987, support frame 2, 10, back roller, 11, coating substrate.

Claims

1. The system includes a mounting frame (1), a circulating transfer pump (3), a material transfer pump (4), a filtration device (5), a supply transfer device (6), a supply pipe (7), and a circulating pipe (8). The circulating transfer pump (3) and the material transfer pump (4) are both fixed to the upper rear end of the mounting frame (1), the filtration device (5) and the supply transfer device (6) are both fixed to the upper middle end of the mounting frame (1), the filtration device (5) is provided between the circulating transfer pump (3) and the supply transfer device (6), and the circulating transfer pump (3), the filtration device (5), and the supply transfer device (6) are sequentially connected in series via the supply pipe (7). A storage device (2) is provided at the rear of the mounting frame (1), and a circulation pipe (8) is connected in series between the output terminal of the storage device (2) and the material transport pump (4), and the output terminal of the circulating transport pump (3) is connected to the input terminal of the storage device (2), and a coating device (9) is slidably provided at the upper end of the mounting frame (1), provided that the width direction perpendicular to the direction of movement of the substrate (11) to be coated is defined as the left-right direction, and the side facing the back roller (10) supporting the substrate (11) is defined as the front, the coating device (9) is located on the left side, The coating apparatus (9) includes a slide rail (92) attached to the upper front end of the mounting frame (1), with fasteners (91) slidably provided on the surface of each of the multiple slide rails (92), a base 2 (93) commonly fixed to the upper ends of the multiple fasteners (91), a base 1 (94) provided on the upper end of the base 2 (93), a multiple support frame 1 (95) fixed to the rear of the base 1 (94), a connecting plate commonly fixed to the tip of the multiple support frame 1 (95), a coating mechanism (96) fixed to the upper end of the base 1 (94), and a multiple coating head roller attachment drivers (97) attached to the upper end of the mounting frame (1) provided on the rear end of the base 2 (93). The coating mechanism (96) includes a coating valve seat (962) fixed to the upper end of the horizontal portion of the base (94), and a plurality of coating valve drivers (961) attached to the front of the base (94) for moving the coating valve (964). A movable groove (963) is provided at the front of the upper end of the coating valve seat (962), and an arc-shaped recess (965) is provided at the rear of the upper end of the coating valve seat (962). Multiple coating valves (964) are slidably provided in the internal cavity of the movable groove (963), and a coating valve seat (966) is fixed at the middle of the tip of the vertical portion of the base (94). It is determined that a baffle (976) is slidably provided in the middle of the upper end of the coating valve seat 2 (966), a plurality of coating valves 2 (968) are provided at the tip of the coating valve 4 (967), a coating valve 3 (969) is slidably provided at the upper end of the coating valve 4 (967) and the upper ends of the plurality of coating valves 2 (968), a baffle (976) is attached to both the left and right ends of the tip of the coating valve 4 (967), and the two baffles (976) are located to the left of the leftmost coating valve 2 (968) and to the right of the rightmost coating valve 2 (968), respectively. A circulation pipe 3 (972) is fixed to the upper end of each of the multiple coating valves 2 (968). Multiple slide grooves (971) corresponding to the same-side circulation pipes (972) are provided at the upper end of the coating valve 3 (969), and each of the multiple circulation pipes 3 (972) is located in one of the multiple slide grooves (971). There are multiple coating valves 2 (968) and 3 (969) arranged along the direction of movement of the substrate (11). A secondary battery thick electrode coating apparatus characterized in that the input end of the circulating pipe (8) is attached to the left and right middle ends of the base (94), and both are connected to the internal cavity of the arc-shaped recess (965).

2. The storage device (2) includes a storage tank (21), with a raw material return pipe and a supply pipe attached symmetrically to the front and rear of the storage tank (21), a discharge pipe attached to the bottom of the storage tank (21), a motor (24) attached to the middle of the upper wall of the storage tank (21), a connecting rod attached to the output of the motor (24) via a coupling, a stirring paddle (22) attached to the lower end of the connecting rod, the input end of the material transport pump (4) connected to the discharge pipe via a circulation pipe (8), and the output end of the circulating transport pump (3) connected to the raw material return pipe via a supply pipe (7), as described in claim 1, for a thick electrode coating device for a secondary battery.

3. Multiple coating valve 3 drivers (973), multiple coating valve 4 drivers (974), and multiple coating valve 2 drivers (975) are attached to the tip of the connecting plate for moving the coating valve 3 (969), the coating valve 4 (967), and the coating valve 2 (968), respectively. The output end piston rods of the multiple coating valve 4 drivers (974) pass through the vertical portion of the base 1 (94) and are all connected to the rear end of the coating valve 4 (967). The coating apparatus for thick electrodes for secondary batteries according to claim 1, characterized in that the output end piston rods of (975) pass through the vertical portion of the base 1 (94) and are connected to the coating valve 2 (968) on the same side, a plurality of coating valve 4 drivers (974) are arranged equally on the left and right sides of a plurality of coating valve 2 drivers (975), and the output end piston rods of a plurality of coating valve 3 drivers (973) pass through the vertical portion of the base 1 (94) and are connected to the rear end of the coating valve 3 (969).

4. The coating apparatus for thick electrodes for secondary batteries according to claim 3, characterized in that the lower part of the outer surface of a plurality of coating valves 2 (968) facing the back roller (10) is provided in an arc shape, an arc-shaped groove (9683) is provided in the upper part of the outer surface of the coating valves 2 (968) facing the back roller (10), a pressure sensor 2 (9682) is attached to the middle of the inner surface of the arc-shaped groove (9683), and a recirculation hole (9681) is provided at the front of the inner surface of the arc-shaped groove (9683) that leads to the internal cavity of the circulation pipe 3 (972) on the same side.

5. The coating apparatus for thick electrodes for secondary batteries according to claim 1, characterized in that the lower part of the tip of the coating valve seat 2 (966) is rounded, and a pressure sensor 1 (9661) is also attached.

6. The secondary battery thickness electrode coating apparatus according to claim 1, characterized in that the lower tip of the coating valve 3 (969) has an arc-shaped, flat, or adjustable structure.

7. The coating apparatus for thick electrodes for secondary batteries according to claim 1, characterized in that a coating head lateral displacement drive device is installed between the base two (93) and base one (94).

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