Pole piece coating device

Abstract

The utility model relates to the pole piece coating technical field, concretely to a kind of pole piece coating device, comprising: stirring mechanism;Conveying pipe is connected to stirring mechanism;The inlet end of coating assembly is communicated with conveying pipe, coating assembly has slit for receiving slurry from stirring mechanism and carries out coating operation, first buffer cavity and second buffer cavity are provided in coating assembly, and first buffer cavity and second buffer cavity are mutually connected by slit;Wherein, first buffer cavity is cylindrical cavity of equal section, first buffer cavity is communicated with the inlet end of coating assembly, configured to direct slurry to second buffer cavity, second buffer cavity is communicated with the outlet end of coating assembly, and second buffer cavity extends first preset distance towards outlet end side.The utility model forms connection double-cavity buffer system in single die, sets up multistage dispersion degassing structure, first buffer cavity and second buffer cavity form sufficient volume, pump machine fills up flow lag when starting instantaneously, absorbs inertial flow when stopping, reduces head-tail waste length, improves slurry utilization.

Description

Technical Field

[0001] This utility model relates to the field of electrode coating technology, specifically to an electrode coating device. Background Technology

[0002] Lithium-ion batteries, as a new generation of green high-energy batteries, have become the mainstream power source in consumer electronics, new energy vehicles, and large-scale energy storage. The electrode is one of the core components of a lithium-ion battery, and its performance directly determines the battery's energy density, cycle life, rate performance, and safety characteristics. Electrodes typically consist of a current collector and an active material slurry layer coated on its surface, and the uniform coating of the slurry is one of the most critical processes in electrode manufacturing. With the increasing demands for energy density and consistency in power batteries, the electrode coating process faces the following challenges: To increase production capacity, modern coating lines generally gradually increase the coating width. When coating with a wide width, the pressure and speed distribution along the width direction at the die exit is very likely to be different, resulting in defects such as thicker coating in the middle and thinner coating at the edges, or horizontal and vertical lines. This seriously affects the uniformity of the surface density of the electrode and the yield of subsequent rolling and slitting processes. Meanwhile, the operating speed of mainstream coating machines is gradually increasing. High-speed coating places higher demands on the stability of slurry supply, the transient response of the die head outlet, and the first blank coating and the last dripping during the start-up and shutdown phases. The traditional scheme of direct connection between the pump body and the die head is prone to pressure overshoot at the moment of pump start-up and shutdown, resulting in an increase in the length of waste material at the beginning and end and a decrease in slurry utilization. Existing technologies use a dual-pump feeding system to reduce pump pulsation, but the dual-pump feeding system is relatively complex and the system coordination is difficult to adjust, resulting in poor performance. In summary, under the actual production conditions, facing the demand for high production speed and high output, the existing coating equipment has problems such as slow start-up and shutdown response, long start and end waste, and uneven coating thickness due to inconsistent slurry uniformity. Therefore, how to develop a new electrode coating equipment that can take into account both high uniformity and high adaptability has become an urgent technical problem to be solved in the field of lithium-ion battery manufacturing. Utility Model Content

[0003] In view of this, this application aims to provide a novel electrode coating device that can take into account both high uniformity and high adaptability, so as to solve the problems of slow start-up and shutdown response, long start and end waste, and inconsistent slurry uniformity of existing coating devices. The electrode coating apparatus according to an embodiment of the present invention includes: A mixing mechanism is used to mix and convey slurry; A conveying pipe, connected to at least one side of the mixing mechanism, is used to convey slurry to the outside of the mixing mechanism; The coating assembly has an inlet end connected to a delivery pipe. The coating assembly has a slit for receiving slurry from the stirring mechanism and performing a coating operation. The coating assembly has a first buffer cavity and a second buffer cavity inside. Both the first buffer cavity and the second buffer cavity extend along the length of the coating assembly. The first buffer cavity and the second buffer cavity are connected in series through the slit. The first buffer cavity is a cylindrical cavity with a uniform cross-section. The first buffer cavity is connected to the inlet end of the coating assembly and is configured to guide the slurry to the second buffer cavity. The second buffer cavity is connected to the outlet end of the coating assembly and extends a first preset distance toward the outlet end.

[0004] According to the electrode coating device of this utility model embodiment, a series dual-cavity buffer system is formed in a single die head, and a multi-stage dispersion degassing structure is set. The first buffer cavity and the second buffer cavity form a sufficient volume. When the pump starts, it instantly fills the flow lag and absorbs the inertial flow when it stops, thereby reducing the length of the head and tail waste materials and improving the slurry utilization rate.

[0005] In some examples of this utility model, the second buffer cavity extends a second preset distance along the height direction of the coating assembly, the inner diameter of the first buffer cavity is greater than the second preset distance, and the inner diameter of the first buffer cavity is less than the first preset distance.

[0006] In some examples of this utility model, the coating assembly includes an upper coating die and a lower coating die fixed to each other, with a slit between them. The lower coating die has an inlet end that communicates with a delivery pipe. At least one outer wall surface of the upper coating die and the lower coating die is inclined in the direction that they approach each other to form a narrowing portion. The slit passes through the narrowing portion and forms the outlet end of the coating assembly.

[0007] In some examples of this utility model, the coating assembly further includes a storage tube disposed in the first buffer cavity. The bottom opening of the storage tube is connected to the inlet end of the coating lower mold. The storage tube is provided with a main shaft, a dispersing frame and a secondary shaft. The main shaft is disposed in the middle of the storage tube, the secondary shaft is arranged in the storage tube and located outside the main shaft, and the dispersing frame is fixed on the main shaft. The middle part of the dispersing frame is spaced at a fixed distance from the main shaft for dispersing the slurry in the storage tube.

[0008] In some examples of this utility model, the coating assembly further includes at least one set of grid plates, which are correspondingly disposed in the second buffer cavity and extend along the length direction of the coating assembly.

[0009] In some examples of this utility model, the stirring mechanism includes a slurry tank, a stirring motor, and a stirring shaft. The stirring motor is connected to the stirring shaft in a driving connection. The stirring motor is fixed to the top of the slurry tank. The stirring shaft passes through the slurry tank. An opening is provided on a set of side walls at opposite positions on the upper part of the slurry tank. The opening is used to convey slurry to the inside and / or outside of the slurry tank.

[0010] In some examples of this utility model, the upper half of the stirring shaft is connected to a mixing plate. The mixing plate is hollow, and baffles are arranged in an array along the width direction of the inner sidewall of the mixing plate. The baffles are used to drive the movement of the slurry in the slurry tank.

[0011] In some examples of this utility model, the lower half of the stirring shaft is connected to at least one fixed ring, which protrudes outward along its radial direction to form a stirring rod. The stirring mechanism also includes multiple dispersing discs, which are fixed circumferentially to the inner wall of the slurry tank and arranged sequentially along the axial direction of the stirring shaft. The dispersing discs are provided with through holes for the slurry to pass through.

[0012] In some examples of this invention, the coating apparatus further includes a buffer tank connected to the delivery pipe, disposed between the stirring mechanism and the coating assembly.

[0013] In some examples of this utility model, multiple sets of connecting plates are connected to the side of the upper coating die and the lower coating die away from the narrowing part. The upper and lower sides of the connecting plates are respectively fixed to the upper coating die and the lower coating die by bolts, and the multiple sets of connecting plates are connected to each other by a fixed shaft.

[0014] The beneficial effects of this utility model are as follows: 1. This utility model forms a series dual-cavity buffer system in a single mold head and sets up a multi-stage dispersion degassing structure. The first buffer cavity and the second buffer cavity form a sufficient volume body. When the pump starts, it instantly fills the flow lag and absorbs the inertial flow when it stops, thereby reducing the length of the head and tail waste materials and improving the slurry utilization rate. 2. This utility model sets up a three-stage collision baffle structure of main shaft, dispersion rack and secondary shaft in the storage tube to perform secondary dispersion and degassing treatment on the slurry, so as to achieve stable slurry coating, prevent horizontal lines or discontinuities during the coating process, and maintain a low sedimentation and agglomeration of the slurry in the cavity during continuous online operation. 3. This utility model sets a hollow mixing plate and an array of baffles in the upper half of the stirring shaft to form a circulating flow field in the top area of ​​the tank, and the side walls are opposite the inlet and outlet ports to eliminate the top vortex; the lower part adopts a fixed ring and agitator to form an upward circulation; together they improve the uniformity of the slurry and ensure the consistency of the outflowing slurry.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the electrode coating apparatus provided in the embodiments of this application; Figure 2 A cross-sectional schematic diagram of the stirring mechanism and conveying pipe provided in the embodiments of this application; Figure 3 A cross-sectional view of the coating assembly and delivery pipe provided in the embodiments of this application. Figure 1 ; Figure 4 A cross-sectional view of the coating assembly and delivery pipe provided in the embodiments of this application. Figure 2 .

[0017] Figure label: 1-Stirring mechanism, 101-Slurry tank, 102-Stirring motor, 103-Stirring shaft, 104-Mixing plate, 105-Baffle, 106-Fixing ring, 107-Stirring rod, 108-Dispersion disc, 109-Through hole; 2-Conveying pipe; 3-Coating assembly, 301-Slit, 302-First buffer cavity, 303-Second buffer cavity, 304-Upper coating die, 305-Lower coating die, 306-Storage tube, 307-Main shaft, 308-Dispersion rack, 309-Secondary shaft, 310-Grid plate, 311-Connecting plate, 312-Fixed shaft; Inlet end 313; Outlet end 314. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of the present utility model and are not intended to limit the present utility model. In the present utility model, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0019] Please see Figure 1-4 This application provides an electrode coating apparatus, comprising: Mixing mechanism 1 is used to mix and convey slurry; The conveying pipe 2 is connected to at least one side of the mixing mechanism 1 and is used to convey slurry to the outside of the mixing mechanism 1; The coating assembly 3 has an inlet end 313 connected to the conveying pipe 2. The coating assembly 3 has a slit 301 for receiving slurry from the stirring mechanism 1 and performing coating operations. The coating assembly 3 has a first buffer cavity 302 and a second buffer cavity 303 inside. The first buffer cavity 302 and the second buffer cavity 303 both extend in the length direction of the coating assembly 3. The first buffer cavity 302 and the second buffer cavity 303 are connected in series through the slit 301. The first buffer cavity 302 is a cylindrical cavity with a uniform cross section. The first buffer cavity 302 is connected to the inlet end 313 of the coating component 3 and is configured to guide the slurry to the second buffer cavity 303. The second buffer cavity 303 is connected to the outlet end 314 of the coating component 3 and extends a first preset distance toward the outlet end 314.

[0020] It should be noted that, as Figure 1 As shown, the length direction of the coating component 3 is... Figure 1 In the X direction. Along the length of the coating assembly 3, the first buffer cavity 302 is a cylindrical cavity with a uniform cross-section. In this embodiment, the electrode coating device, by setting the first buffer cavity 302 and the second buffer cavity 303, and connecting them in series through the slit 301, achieves effective buffering and uniform distribution of the slurry flow, improving the stability of the coating process and the consistency of the coating quality. In the specific implementation of this embodiment, the first buffer cavity 302 adopts a cylindrical structure with a uniform cross-section, which can provide a transition space with stable volume and low flow resistance in the early stage of the slurry entering the coating assembly 3, alleviate the impact caused by the fluctuation of the slurry flow rate output by the stirring mechanism 1, and avoid the slurry from generating turbulence or local pressure rise at the inlet, thereby reducing the risk of bubble formation and coating defects. Then, the slurry enters the second buffer cavity 302 through the slit 301. 3. The second buffer cavity 303 extends a first preset distance toward the outlet end 314 of the coating component 3 to further achieve the pressure equalization effect of the slurry. The setting of the second buffer cavity 303 causes the pressure and flow rate of the slurry to tend to be consistent in the length direction of the coating component 3 before reaching the outlet end 314, ensuring that the slurry can flow out from the outlet end 314 in a uniform and stable state, achieving thickness uniformity during wide-width coating. At the same time, since the first buffer cavity 302 and the second buffer cavity 303 are connected in series through the slit 301 rather than directly connected, the flow path of the slurry is extended, the laminar flow characteristics of the slurry are enhanced, dead zones and stagnation phenomena are reduced, which helps to prevent slurry sedimentation or agglomeration and is suitable for coating operations of high solid content or high viscosity slurries.

[0021] It is important to emphasize that the first buffer cavity 302, the second buffer cavity 303, and the slit 301 together constitute a buffer system. When the external pump delivers slurry, the slurry in the cavity can promptly fill the pipeline lag when the pump starts. The outlet end 314 controls the synchronous outflow, eliminating the impact of the first blank coating and the initial pressure surge on the coating process. When the pump stops, due to the slurry's inherent viscosity, the cavity volume can absorb the inertial flow. After the pump stops, the external power source is cut off, and the slurry flow is interrupted at the outlet end 314, preventing the tail sheet from dripping. As a result, the coating start-up and shutdown response time is shortened, the slurry utilization rate is improved, and the length of waste material at the beginning and end of the electrode sheet is reduced.

[0022] In some embodiments, such as Figure 3 As shown, the second buffer cavity 303 extends a second preset distance along the height direction of the coating component 3, the inner diameter of the first buffer cavity 302 is greater than the second preset distance, and the inner diameter of the first buffer cavity 302 is less than the first preset distance.

[0023] Specifically, the height direction of the coating component 3 is... Figure 3 In the Z direction. In this embodiment, the second buffer cavity 303 extends not only along one side of the outlet end 314, but also along the height direction by a second preset distance, expanding the accommodating space of the second buffer cavity 303. It can accommodate more slurry inside, so that it can be discharged immediately at the outlet end 314 when the pump is started, without waiting for the pipeline to be filled. The inner diameter of the first buffer cavity 302 is larger than the second preset distance, ensuring that the radial dimension of the cylindrical cavity is sufficient to accommodate instantaneous backflow, avoiding fluctuations in the slurry at the inlet end 313 due to insufficient space. At the same time, its inner diameter is smaller than the first preset distance, preventing the slurry from forming eddies or stagnation in the cavity, maintaining laminar flow stability. Through the size matching of the two cavities, the slurry forms a continuous narrowing path from the first buffer cavity 302, the second buffer cavity 303 to the outlet end 314 of the slit 301, smoothing the velocity gradient and pressure difference, improving the neatness of the coating edge, and the consistency of the coating thickness.

[0024] In some embodiments, such as Figure 3 As shown, the coating assembly 3 includes an upper coating die 304 and a lower coating die 305 fixed to each other, with a slit 301 between them. The lower coating die 305 is provided with an inlet end 313 connected to the delivery pipe 2. At least one outer wall surface of the upper coating die 304 and the lower coating die 305 is inclined in the direction of their approach to each other, forming a narrowing section. The slit 301 passes through the narrowing section and forms an outlet end 314 of the coating assembly 3.

[0025] Specifically, the narrowing section reduces the contact area between the outlet end 314 and the substrate, allowing the slurry to be scraped and fixed as soon as it leaves the slit 301. This results in minimal edge rebound and high coating edge neatness, eliminating the need for subsequent coating trimming. In the specific implementation of this embodiment, during the coating process, the inclined narrowing section guides excess slurry to the outside of the coating area, preventing slurry from accumulating and drying at the edge of the coating area, thus avoiding edge thickening issues.

[0026] In some embodiments, such as Figure 4 As shown, the coating assembly 3 also includes a storage tube 306, which is disposed in the first buffer cavity 302. The bottom opening of the storage tube 306 is connected to the inlet end 313 of the coating lower mold 305. The storage tube 306 is provided with a main shaft 307, a dispersing frame 308 and a secondary shaft 309. The main shaft 307 is disposed in the middle of the storage tube 306. The secondary shaft 309 is arranged in a ring in the storage tube 306 and located outside the main shaft 307. The dispersing frame 308 is fixed on the main shaft 307. The middle part of the dispersing frame 308 is spaced at a fixed distance from the main shaft 307 for dispersing the slurry in the storage tube 306.

[0027] Specifically, the storage tube 306 is fixed in the center of the first buffer cavity 302. After the slurry flows in from the bottom opening of the storage tube 306, it collides with the outer wall of the main shaft 307 and flows in all directions. Then it collides with the support structure on the circumferentially distributed dispersion rack 308, which changes the flow direction again, forming multiple diversions. The remaining slurry is blocked by the outer wall of the secondary shaft 309, generating a reverse vortex and slowing down the flow speed. After the slurry is dispersed and degassed, it smoothly overflows into the second buffer cavity 303 through the slit 301. The remaining air bubbles float up during the reversal process and remain on the side of the storage tube 306 away from the slit 301, no longer flowing downwards. Through a series of continuous collisions and diversions, the slurry is fully dispersed and initially degassed. The material flow entering the slit 301 afterward has high uniformity, and the viscosity and flowability of the dispersed slurry are more consistent. Under a certain pump power, the outflow is more stable, which makes the coating surface smoother.

[0028] In one embodiment, for example, a plurality of flow-receiving plates are arranged around the storage tube 306 at fixed intervals along its axis. The flow-receiving plates extend along the length of the storage tube 306 and have at least one set of elongated holes inclined to the plate surface. After the slurry collides with the plate surface, it moves towards the elongated holes. As the elongated holes change their flow direction angle, the slurry is cut into multiple oblique jets, dispersing its original kinetic energy and causing the air bubbles it carries to float upward with the deflection, thus completing the dispersion and degassing. Subsequently, the slurry overflows into the second buffer cavity 303 at a low speed and uniformly. The flow-receiving plates can be set to be welded and fixed to the cavity wall, thereby improving the connection strength.

[0029] In another embodiment, for example, a fixed column with protrusions on its surface can be disposed inside the storage tube 306. The protrusions can be staggered along the axial direction of the fixed column. When the slurry flows upward from the bottom opening of the storage tube 306, it directly impacts the fixed column and the protrusions. The flow direction is cut and dispersed by the protrusions, forming multiple small eddies. The flow velocity is reduced due to resistance. The slurry then slowly overflows from the periphery of the fixed column into the second buffer cavity 303, completing the dispersion and degassing. The two ends of the fixed column can be fixed to the end faces of the storage tube 306.

[0030] In some embodiments, such as Figure 4 As shown, the coating assembly 3 also includes at least one set of grid plates 310, which are correspondingly disposed in the second buffer cavity 303 and extend along the length direction of the coating assembly 3.

[0031] It should be noted that the grid plate 310 is disposed in the second buffer cavity 303. The grid plate 310 is laid along the entire length of the second buffer cavity 303, dividing the cavity into multiple parallel sub-channels. After the slurry enters, it is diverted by the cavity, and the flow velocity distribution in each sub-channel is flattened. The pressure difference between the channels can be balanced in real time through the gap between the grid plates 310, thereby making the flow more uniform. The wall surface of the grid plate 310 blocks the lateral fluctuation of the slurry and avoids the low-speed stagnation zone inside the cavity. Through the diversion and flow stabilization effect of the grid plate 310, the slurry at the outlet end 314 of the slit 301 maintains a consistent pressure and velocity in the length direction of the coating assembly 3, preventing the generation of horizontal lines and thin-thickness bands on the surface of the electrode after coating.

[0032] In some embodiments, such as Figure 1 and Figure 2 As shown, the stirring mechanism 1 includes a slurry tank 101, a stirring motor 102, and a stirring shaft 103. The stirring motor 102 is connected to the stirring shaft 103 in a driving connection. The stirring motor 102 is fixed to the top of the slurry tank 101. The stirring shaft 103 passes through the slurry tank 101. An opening is provided on a set of opposite side walls at the upper part of the slurry tank 101. The opening is used to convey slurry into and / or to the outside of the slurry tank 101.

[0033] Specifically, the stirring motor 102 is fixed to the top of the slurry tank 101, and the stirring shaft 103 extends vertically into the tank. The two side wall openings on the upper part of the tank are arranged opposite each other, so that the slurry can enter and exit on the same level, forming a transverse circulation. The slurry flows in from one side opening and enters the circulation range of the stirring shaft 103 and its driving components. After circulation, it flows out from the opposite side opening, reducing the flow dead zone. The stirring shaft 103 only penetrates the top of the tank once. The side wall opening is connected by a fixed flange, which reduces the difficulty of rotary sealing and improves the operational stability of the tank.

[0034] In some embodiments, such as Figure 2As shown, the upper half of the stirring shaft 103 is connected to a mixing plate 104. The mixing plate 104 is hollow, and baffles 105 are arranged in an array along the width direction of the inner sidewall of the mixing plate 104. The baffles 105 are used to drive the movement of slurry in the slurry tank 101.

[0035] It should be noted that the mixing plate 104 is fixed to the upper part of the stirring shaft 103. The mixing plate 104 can be a ring structure, hollow inside and with baffles 105 arranged along its width. In the specific implementation of this embodiment, when the stirring shaft 103 rotates, the mixing plate 104 lifts the initially mixed slurry again, and the baffles 105 deflect and divide the material flow multiple times, further dispersing any remaining soft agglomerates in the slurry. The continuous rotation of the plate forms a directional push at the top of the tank, and the slurry is orderly sent to the opposite opening, avoiding cross-flow between dispersed and undispersed areas, ensuring that the opposite opening always receives a uniform, agglomerated slurry, resulting in a more consistent coating thickness downstream. The cooperative structure of the mixing plate 104 and the baffles 105 reduces weight and shaft load, while providing additional flow space to prevent local shearing from causing heat generation and maintaining stable slurry performance.

[0036] In some embodiments, such as Figure 2 As shown, the lower half of the stirring shaft 103 is connected to at least one fixed ring 106. The fixed ring 106 protrudes outward along its radial direction to form a stirring rod 107. The stirring mechanism 1 also includes a plurality of dispersing discs 108. The plurality of dispersing discs 108 are fixed circumferentially on the inner wall of the slurry tank 101 and arranged sequentially along the axial direction of the stirring shaft 103. The dispersing discs 108 are provided with through holes 109 for the slurry to pass through. It should be noted that the fixing ring 106 of the lower half of the stirring shaft 103 rotates with the shaft, and the stirring rod 107 lifts and disperses the concentrated slurry gathered at the bottom, while generating a continuous upward flow, which transports large particles or agglomerates that have not yet been homogenized upward. During the upward process, the slurry comes into contact with the dispersing discs 108 set in stages. The through holes 109 on each disc cut and deflect the material flow, and the disc body separates the slurry with different homogeneity. The high concentration area at the bottom will not directly mix with the already dispersed area at the top, thereby avoiding the outflow of slurry with different homogeneity and improving the coating uniformity and coating effect.

[0037] In some embodiments, such as Figure 1 As shown, the coating device also includes a buffer tank 4 connected to the conveying pipe 2, which is located between the stirring mechanism 1 and the coating assembly 3. Specifically, the buffer tank 4 is connected in series in the middle section of the delivery pipe 2, forming a volume expansion section between the stirring mechanism 1 and the coating assembly 3. The slurry first fills the buffer tank 4 and then overflows into the downstream pipeline. This allows the pulse generated by the pump to be absorbed by the liquid surface in the tank, resulting in a stable outlet flow and the coating thickness no longer fluctuating with the pump stroke.

[0038] In some embodiments, such as Figure 3 and Figure 4 As shown, multiple sets of connecting plates 311 are connected to the side of the upper coating die 304 and the lower coating die 305 away from the narrowing section. The upper and lower sides of the connecting plates 311 are fixed to the upper coating die 304 and the lower coating die 305 respectively by bolts. The multiple sets of connecting plates 311 are connected to each other by a fixed shaft 312.

[0039] Specifically, the connecting plate 311 is arranged on the non-narrowing end of the die head, and the upper coating die 304 and the lower coating die 305 are connected into one piece by bolts. Multiple sets of connecting plates 311 are connected laterally by a fixed shaft 312 to form a rigid frame, which can distribute the bolt preload evenly to the entire die body through the connecting plate 311, and keep the opening of the slit 301 consistent, avoiding local overpressure or loosening from affecting the opening of the slit 301. The fixed shaft 312 connects each connecting plate 311 into a whole, which improves the bending stiffness of the die head, reduces the deformation of the upper and lower die openings when internal pressure is applied, and makes the coating thickness more uniform. The connecting plate 311 and the fixed shaft 312 are both set on the non-narrowing area side, away from the working surface of the coating slurry, so there is no need to contact the die opening when the bolts are loose or when maintenance and adjustment are needed, preventing the normal outflow of the slurry from being affected. The embodiments of this utility model have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. An electrode coating apparatus, characterized in that, include: A mixing mechanism is used to mix and convey slurry; A conveying pipe, connected to at least one side of the stirring mechanism, is used to convey slurry to the outside of the stirring mechanism; A coating assembly, the inlet end of which is connected to the delivery pipe, the coating assembly having a slit for receiving slurry from the stirring mechanism and performing a coating operation, the coating assembly having a first buffer cavity and a second buffer cavity inside, both the first buffer cavity and the second buffer cavity extending along the length direction of the coating assembly, and the first buffer cavity and the second buffer cavity being connected in series through the slit; The first buffer cavity is a cylindrical cavity with a uniform cross-section. The first buffer cavity is connected to the inlet end of the coating assembly and is configured to guide the slurry to the second buffer cavity. The second buffer cavity is connected to the outlet end of the coating assembly and extends a first preset distance toward the outlet end.

2. The electrode coating apparatus according to claim 1, characterized in that, The second buffer cavity extends a second preset distance along the height direction of the coating assembly. The inner diameter of the first buffer cavity is greater than the second preset distance, and the inner diameter of the first buffer cavity is less than the first preset distance.

3. The electrode coating apparatus according to claim 1, characterized in that, The coating assembly includes an upper coating die and a lower coating die fixed to each other, with the slit between them. The lower coating die has an inlet end that communicates with the delivery pipe. At least one outer wall surface of the upper coating die and the lower coating die is inclined in a direction that brings them closer together, forming a narrowing portion. The slit passes through the narrowing portion and forms the outlet end of the coating assembly.

4. The electrode coating apparatus according to claim 3, characterized in that, The coating assembly further includes a storage tube disposed in the first buffer cavity. The bottom opening of the storage tube is connected to the inlet end of the coating lower mold. The storage tube is internally provided with a main shaft, a dispersing frame, and a secondary shaft. The main shaft is disposed in the middle of the storage tube. The secondary shaft is arranged in the storage tube and located outside the main shaft. The dispersing frame is fixed on the main shaft. The middle part of the dispersing frame is spaced at a fixed distance from the main shaft for dispersing the slurry in the storage tube.

5. The electrode coating apparatus according to claim 3, characterized in that, The coating assembly further includes at least one set of grid plates, which are correspondingly disposed in the second buffer cavity and extend along the length direction of the coating assembly.

6. The electrode coating apparatus according to claim 1, characterized in that, The stirring mechanism includes a slurry tank, a stirring motor, and a stirring shaft. The stirring motor is connected to the stirring shaft and is fixed to the top of the slurry tank. The stirring shaft passes through the slurry tank. An opening is provided on a set of opposite side walls at the upper part of the slurry tank. The opening is used to convey slurry into the slurry tank and / or to the outside of the slurry tank.

7. The electrode coating apparatus according to claim 6, characterized in that, The upper half of the stirring shaft is connected to a mixing plate. The mixing plate is hollow and has baffles arranged in an array along the width of its inner wall. The baffles are used to drive the movement of the slurry in the slurry tank.

8. The electrode coating apparatus according to claim 6, characterized in that, The lower half of the stirring shaft is connected to at least one fixed ring, which protrudes outward along its radial direction to form a stirring rod. The stirring mechanism also includes multiple dispersing discs, which are fixed circumferentially to the inner wall of the slurry tank and arranged sequentially along the axial direction of the stirring shaft. The dispersing discs are provided with through holes for the slurry to pass through.

9. The electrode coating apparatus according to claim 1, characterized in that, The coating apparatus also includes a buffer tank connected to the delivery pipe, which is disposed between the stirring mechanism and the coating assembly.

10. The electrode coating apparatus according to claim 3, characterized in that, Multiple sets of connecting plates are connected to the upper coating die and the lower coating die on the side away from the narrowing portion. The upper and lower sides of the connecting plates are respectively fixed to the upper coating die and the lower coating die by bolts, and the multiple sets of connecting plates are connected to each other by a fixed shaft.

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