A die flow channel structure, a coating die, and a coating device

Abstract

The utility model discloses a die flow channel structure, coating die and coating device, include: at least one cavity, at least one feed channel, multistage symmetry shunt structure, symmetry shunt structure includes at least one sub runner, and sub runner has sub runner feed port and two sub runner discharge port, and the sub runner feed port of symmetry shunt structure in first stage is communicated with feed channel, and all sub runner discharge ports of symmetry shunt structure in last stage are communicated with cavity, and two sub runner discharge ports of each sub runner are about the symmetry distribution of sub runner feed port of this sub runner, and each sub runner discharge port of symmetry shunt structure in same level is arranged at equal intervals. Through multistage symmetry shunt structure, and sub runner discharge port is about the symmetry distribution of feed port and is arranged at equal intervals, and it is ensured that each flow channel flow distribution is consistent, and the difference of edge and central region discharge amount is reduced significantly.

Description

Technical Field

[0001] This utility model relates to the technical field of coating machines and accessories, specifically to a die head flow channel structure, a coating die head, and a coating device. Background Technology

[0002] As the lithium-ion battery industry continues to demand high-performance, low-cost, and multilayer products, multilayer composite coating technology is becoming increasingly mainstream. The coating die, as a key component for achieving high-quality slurry coatings, has a significant impact on the areal density stability, consistency, and interlayer structure of the coating.

[0003] Currently, common coating dies are single-layer, single-inlet, multi-outlet structures. They achieve parallel dispensing of multiple channels by sequentially diverting a slurry within the die, forming a uniform coating at the lip. Chinese patent CN113649230A discloses a coating die that adjusts the areal density solely through adjustment devices at the lip, such as a micro-head and push-pull rod at the end. This approach is often ineffective when dealing with significant differences in slurry rheology or different coating processes. The areal density distribution still suffers from an "inverted U-shape" problem: due to the varying effects of channel position on flow resistance, the amount of material dispensed at the edges is often less than in the center, resulting in uneven slurry thickness. Utility Model Content

[0004] In view of this, the present invention provides a die head flow channel structure, a coating die head, and a coating device to solve the problem of uneven slurry thickness output by the current coating die head.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] Firstly, this utility model provides a die head flow channel structure, including:

[0007] At least one cavity for containing and guiding slurry;

[0008] At least one feed channel for conveying slurry into the cavity;

[0009] A multi-level symmetrical flow-dividing structure is provided, with each level of the symmetrical flow-dividing structure positioned between regions extending from the feed channel to the cavity. Each symmetrical flow-dividing structure includes at least one sub-channel, each sub-channel having a sub-channel feed inlet and two sub-channel discharge outlets. The sub-channel feed inlet of the first-level symmetrical flow-dividing structure is connected to the feed channel. The sub-channel feed inlets of the remaining levels of the symmetrical flow-dividing structure, located away from the first-level symmetrical flow-dividing structure, are connected to the sub-channel discharge outlets of the previous level of the symmetrical flow-dividing structure. All sub-channel discharge outlets of the last-level symmetrical flow-dividing structure are connected to the cavity. The two sub-channel discharge outlets of each sub-channel are symmetrically distributed about the sub-channel feed inlet of that sub-channel. The sub-channel discharge outlets of the same level of the symmetrical flow-dividing structure are arranged at equal intervals.

[0010] The beneficial effects of the above-mentioned die head flow channel structure are as follows: through the multi-level symmetrical flow distribution structure, the sub-flow channel outlets are symmetrically distributed about the inlet and arranged at equal intervals, ensuring that the flow distribution of each flow channel is consistent, effectively solving the problem of uneven surface density of the "inverted U-shape" caused by the difference in channel position in the prior art, and significantly reducing the difference in the amount of material discharged between the edge and the central area.

[0011] The symmetrical flow splitting design shortens the flow path of the slurry in the cavity. Combined with the equal area and equal distance flow channel layout, it reduces the resistance difference during the flow of the slurry, resulting in a lower pressure drop inside the cavity. This promotes the rapid spreading and uniform distribution of the slurry, providing a stable initial state for subsequent coating.

[0012] This invention employs a multi-stage symmetrical flow distribution method (such as one outlet for two, two outlets for four, or four outlets for eight), with pre-set and fixed flow channels. The symmetrical structure does not rely on on-site adjustments, ensuring a balanced flow of slurry before it enters the cavity. Within the cavity, the slurry is guided and spread out over a short distance, significantly reducing lateral pressure drop and thus improving the consistency of the coating surface density, providing a stable foundation for subsequent slit lip coating.

[0013] The technical solution is further optimized so that the number of sub-channels in each stage of the symmetrical flow splitting structure is twice that of the previous stage, and the final stage of the symmetrical flow splitting structure forms 2 n There are several sub-channel outlets, where n is the number of flow stages, and n≥2.

[0014] The technical solution is further optimized by setting the distance between the outlets of two sub-channels in the previous stage to twice the distance between the outlets of two sub-channels in the next stage. Combined with the design of doubling the number of sub-channels at each stage, this ensures that all final sub-channel outlets are evenly spaced along the die width. This geometric progression avoids mutual interference in densely populated areas of the channels, resulting in more uniform lateral coverage of the slurry at the cavity inlet and resolving the problem of localized flow superposition caused by traditional non-uniform spacing.

[0015] The technical solution is further optimized, and the sub-channel includes:

[0016] A transverse distribution channel, wherein the transverse distribution channel is in the same transverse direction as the cavity, and the sub-channel inlet is located in the middle of the transverse distribution channel;

[0017] Two longitudinal distribution channels are respectively located at both ends of the transverse distribution channel and are connected to the transverse distribution channel. The longitudinal distribution channels are in the same longitudinal direction as the cavity, and the end of each longitudinal distribution channel is connected to the outlet of the corresponding sub-channel.

[0018] The beneficial effects of the above technical solution are as follows: the design of feeding in the middle of the transverse distribution channel enables the slurry to be symmetrically divided from the source. Combined with the longitudinal distribution channels of equal length at both ends, it ensures that the flow path length and flow resistance of the slurry on both sides are completely consistent, fundamentally eliminating the problem of flow deviation caused by feeding on one side.

[0019] Secondly, this utility model provides a coating die head, comprising:

[0020] First mold head;

[0021] Second mold head;

[0022] A gasket is disposed between the first mold head and the second mold head;

[0023] The first or second die head is provided with a die head flow channel structure. The gasket forms a slit coating gap with the first or second die head. The slit coating gap is connected to the cavity. The slit coating gap is used to uniformly coat the slurry flowing through the die head flow channel structure onto the target substrate.

[0024] The coating die head described above has the same beneficial effects as the die head flow channel structure of the first aspect of this utility model, and will not be described in detail here.

[0025] Further optimization of the technical solution also includes:

[0026] A third mold head is disposed between the first mold head and the second mold head;

[0027] The gasket includes a first gasket and a second gasket. The first gasket is sandwiched between the first die head and the third die head to form a first slit coating gap. The second gasket is sandwiched between the second die head and the third die head to form a second slit coating gap. The second die head and the third die head are provided with a die head flow channel structure. The cavity of the die head flow channel structure of the second die head is relatively independent from the cavity of the die head flow channel structure of the third die head. The cavity of the die head flow channel structure of the third die head is connected to the first slit coating gap, and the cavity of the die head flow channel structure of the second die head is connected to the second slit coating gap.

[0028] The beneficial effects of the above technical solution are as follows: By adopting a double-layer die head structure, independent slurry supply cavities are formed between the first and third dies, and between the second and third dies. These two cavities are completely isolated and do not interfere with each other, allowing for the separate supply of slurries with different properties, thus enabling simultaneous composite coating of two slurries. This structure significantly improves the die head's adaptability to slurries with different rheological properties, and is particularly suitable for double-layer coating systems with significant functional differences or large differences in particle size distribution.

[0029] To further optimize the technical solution, the first slit coating gap is arranged horizontally, the second slit coating gap is arranged obliquely, and the ends of the first slit coating gap and the second slit coating gap intersect and a coating lip is provided at the intersection.

[0030] Further optimization of the technical solution also includes:

[0031] An adjustment mechanism, which is disposed on the first die head and / or the second die head, is used to adjust the height of the slit coating gap to adapt to the needs of different coating thicknesses.

[0032] To further optimize the technical solution, multiple adjustment mechanisms are provided, which are distributed at intervals along the width direction of the coating die head, and the multiple adjustment mechanisms can operate synchronously or independently.

[0033] The adjustment mechanism includes an actuator and an adjustment block. The adjustment block is connected to the output end of the actuator and is used to adjust the height of the slit coating gap.

[0034] Thirdly, this utility model provides a coating device, including the aforementioned coating die head.

[0035] The coating device described above has the same beneficial effects as the coating die head of the second aspect of this utility model, and will not be described in detail here. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 A schematic diagram of a four-channel distribution in a mold head flow channel structure provided by this utility model;

[0038] Figure 2 A schematic diagram of an eight-channel distribution for a mold head flow channel structure provided by this utility model;

[0039] Figure 3 A schematic diagram of a sixteen-channel distribution in a mold head flow channel structure provided by this utility model;

[0040] Figure 4 An exploded view of a coating die provided by this utility model;

[0041] Figure 5 A cross-sectional view of a coating die provided by this utility model;

[0042] Figure 6 This is a schematic diagram of the structure of an adjustment mechanism for a coating die head provided by this utility model.

[0043] Figure label:

[0044] 1. First mold head, 2. Second mold head, 3. Third mold head, 4. First gasket, 5. Second gasket, 6. Cavity, 61. First cavity, 62. Second cavity, 7. Feed channel, 8. Adjustment mechanism, 81. First adjustment mechanism, 82. Second adjustment mechanism, 83. Actuator, 84. Adjustment block, 9. Symmetrical flow distribution structure, 91. Sub-flow channel, 911. Sub-flow channel inlet, 912. Sub-flow channel outlet, 914. Lateral distribution channel, 915. Longitudinal distribution channel, 10. Coating lip. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0046] In practical use, existing single-layer coating dies allow operators to fine-tune the material output from each channel via an end-effector adjustment mechanism. However, the adjustment range is limited, only compensating for small fluctuations in areal density. When areal density differences are significant, the end-effector adjustment cannot effectively correct the problem, resulting in uneven coating.

[0047] Furthermore, when dealing with slurries with different rheological properties, the existing die head structure can maintain a certain degree of uniformity for slurries with good rheological properties, but it is often difficult to achieve accurate control when dealing with slurries with poor flowability or high sensitivity. The areal density distribution problem becomes more prominent, and the die head has poor adaptability.

[0048] Therefore, the technical problems to be solved by this utility model include: how to achieve higher precision pre-diversion control in the die head processing stage through structural optimization, reducing the dependence on the end adjustment mechanism; and how to improve the compatibility of the die head with different rheological properties of slurries, so that it can stably output a highly consistent coating under various working conditions.

[0049] The following is combined with Figures 1 to 6 As shown, the first aspect of the present invention describes in detail the flow channel structure of the die head, the second aspect of the present invention describes the coating die head, and the third aspect of the present invention describes the coating device.

[0050] According to an embodiment of the present invention, in a first aspect, a die head flow channel structure is provided, combined with... Figures 1 to 3 As shown, it includes a cavity 6, a feed channel 7, and a symmetrical flow splitting structure 9.

[0051] The cavity 6 is provided with at least one cavity 6 for containing and guiding slurry.

[0052] At least one feed channel 7 is provided, which is used to feed slurry into the cavity 6.

[0053] The symmetrical flow splitting structure 9 has multiple levels, with each level positioned between the areas from the feed channel 7 to the cavity 6. Each symmetrical flow splitting structure 9 includes at least one sub-channel 91, each having a sub-channel inlet 911 and two sub-channel outlets 912. The sub-channel inlet 911 of the first-level symmetrical flow splitting structure 9 is connected to the feed channel 7. The sub-channel inlets 911 of the remaining levels of the symmetrical flow splitting structure, located away from the first level, are connected to the sub-channel outlets 912 of the previous level. All sub-channel outlets 912 of the last level of the symmetrical flow splitting structure are connected to the cavity 6. The two sub-channel outlets 912 of each sub-channel 91 are symmetrically distributed about the sub-channel inlet 911 of that sub-channel 91. The sub-channel outlets 912 of the same level of the symmetrical flow splitting structure are arranged at equal intervals.

[0054] The aforementioned die head flow channel structure utilizes a multi-stage symmetrical flow distribution structure (such as "one-to-two, two-to-four, four-to-eight"), as shown below. Figure 2 As shown, the sub-channel outlets are symmetrically distributed with equal spacing about the inlet, ensuring consistent flow distribution in each channel. This effectively solves the problem of uneven surface density in the "reverse U-shape" caused by differences in channel position in the existing technology, and significantly reduces the difference in discharge volume between the edge and central areas.

[0055] The symmetrical flow splitting design shortens the flow path of the slurry in the cavity. Combined with the equal area and equal distance flow channel layout, it reduces the resistance difference during the flow of the slurry, resulting in a lower pressure drop inside the cavity. This promotes the rapid spreading and uniform distribution of the slurry, providing a stable initial state for subsequent coating.

[0056] The symmetrical flow splitting structure is formed in one piece through precision machining, without any dynamically adjustable parts. This avoids mechanical errors caused by adjustment mechanisms, ensures the long-term stability of flow channel size and flow splitting ratio, and improves the repeatability and consistency of coating products from different batches.

[0057] The number of flow channels can be flexibly configured, such as one outlet for four (e.g., ...). Figure 1 As shown), one out of eight (as shown) Figure 2 As shown), one out of sixteen (as shown) Figure 3 As shown in the figure, it is suitable for coating scenarios with small width and high precision or large width and high production capacity, and is also compatible with high viscosity slurries.

[0058] High initial consistency reduces the burden and time of end-point adjustment. The high consistency of initial flow diversion reduces reliance on the lip end adjustment mechanism, requiring only minor compensation to meet accuracy requirements, shortening the adjustment cycle and improving production efficiency. Because the flow leveling distance of the slurry inside the cavity is shortened, the pressure drop is smaller, and the flow uniformity is high, resulting in a more consistent initial state of the slurry before exiting the lip. Therefore, the adjustment range of the adjustment components is smaller, and the adjustment cycle is shorter, reducing the operator's adjustment burden and improving production efficiency.

[0059] This embodiment is applicable to high-viscosity, high-speed coating processes. In actual testing, this die structure can adapt to high-viscosity systems with slurry viscosities up to 14000 mPa·s (conventional viscosities are 3000-8000 mPa·s), even with a coating surface density significantly higher than conventional (conventional surface density is 250 g / m²). 2 Under these conditions, the uniformity of the wet film surface density can still be controlled within ±1%, demonstrating excellent stability and applicability.

[0060] In summary, this embodiment employs a multi-stage symmetrical flow distribution method (such as one outlet for two, two outlets for four, or four outlets for eight), with a pre-set and fixed flow channel. The symmetrical structure does not rely on on-site adjustments, ensuring a balanced flow rate of the slurry before entering the cavity. Within the cavity, the slurry is guided and spread out over a short distance, significantly reducing lateral pressure drop and improving the consistency of the coating surface density, thus providing a stable foundation for subsequent slit lip coating.

[0061] In some embodiments, the number of sub-channels 91 in each stage of the symmetrical flow splitting structure is twice that of the previous stage of the symmetrical flow splitting structure, and the last stage of the symmetrical flow splitting structure forms 2 n There are 912 sub-channel outlets, where n is the number of flow stages, and n≥2. Precise control of the number of flow stages is achieved through a geometric progression design where the number of sub-channels in each stage is twice that of the previous stage (e.g., 4 outlets when n=2, 8 outlets when n=3). The number of flow stages n≥2 ensures at least 4 symmetrically distributed outlets, and with a layout of equal area and equal spacing, the flow ratio of each stage is strictly maintained at 1:1, eliminating flow deviations caused by asymmetrical flow stage numbers at the source.

[0062] In some embodiments, the spacing between the two sub-channel outlets 912 located in the upper-level sub-channel 91 is twice the spacing between the two sub-channel outlets 912 located in the lower-level sub-channel 91. Combined with the design of doubling the number of sub-channels at each level, this ensures that all final sub-channel outlets 912 are evenly distributed in the die head width direction (e.g., when n=3, the 8 sub-channel outlets are evenly arranged). This geometric progression avoids mutual interference in densely populated channel areas, resulting in more uniform lateral coverage of the slurry at the cavity inlet and solving the problem of localized flow superposition caused by traditional non-uniform spacing.

[0063] In some embodiments, the sub-channel 91 includes a transverse distribution channel 914 and two longitudinal distribution channels 915. The transverse distribution channel 914 is in the same transverse direction as the cavity 6, and the sub-channel inlet 911 is located in the middle of the transverse distribution channel 914. The two longitudinal distribution channels 915 are respectively located at both ends of the transverse distribution channel 914 and are connected to the transverse distribution channel 914. The longitudinal distribution channels 915 are in the same longitudinal direction as the cavity 6, and the end of each longitudinal distribution channel 915 is connected to the corresponding sub-channel outlet 912. The design of feeding in the middle of the transverse distribution channel 914 enables the slurry to be symmetrically divided from the source. Combined with the longitudinal distribution channels 915 of equal length at both ends, it ensures that the flow path length and flow resistance of the slurry on both sides are completely consistent, fundamentally eliminating the flow deviation problem caused by feeding from one side.

[0064] Combination Figure 2 As shown, after the slurry enters through the sub-channel inlet 911, it is first divided into two branches along the width of the die head by a main channel. Each branch is further divided into four equally divided longitudinal distribution channels, forming a symmetrical "one outflow, eight outflow" distribution structure. The eight outflow channels are evenly distributed along the width of the cavity, with the outlet located inside the cavity, allowing the slurry to enter the cavity in sections. The corresponding outlet positions are evenly distributed according to the width of the substrate, ensuring that the area controlled by each channel is consistent. This diversion structure is positioned and formed during the die head processing stage, without any dynamically adjustable components, ensuring the stability and repeatability of the outflow structure.

[0065] After the slurry enters the cavity 6 from multiple sub-channel outlets, it is diffused and spread through the guide chambers located within the cavity 6. Because the corresponding area of ​​each channel is equal and symmetrical, the slurry distribution within the cavity becomes faster and more uniform. The thickness and diffusion angle of the cavity are optimized to ensure reduced lateral pressure drop and improved slurry spreading efficiency. Each cavity is ultimately connected to a corresponding slit lip, which forms a slit coating of the slurry. The upper and lower layers of slurry are discharged through their respective lips, simultaneously achieving a double-layer composite coating on the substrate surface.

[0066] According to an embodiment of the present invention, in a second aspect, a coating die head is provided, including a first die head 1, a second die head 2, a gasket, and fasteners for fixing and connecting them. The gasket is disposed between the first die head 1 and the second die head 2. The first die head 1 or the second die head 2 is provided with a die head flow channel structure, and the gasket and the first die head 1 or the second die head 2 form a slit coating gap, which communicates with a cavity 6. The slit coating gap is used to uniformly coat the slurry flowing through the die head flow channel structure onto the target substrate.

[0067] The coating die head also includes a third die head 3, which is disposed between the first die head 1 and the second die head 2. The gaskets include a first gasket 4 and a second gasket 5. The first gasket 4 is disposed between the first die head 1 and the third die head 3, and the second gasket 5 is disposed between the third die head 3 and the second die head 2. The second die head 2 and the third die head 3 are provided with die head flow channel structures. The first gasket 4 is sandwiched between the first die head 1 and the third die head 3 to form a first slit coating gap, and the second gasket 5 is sandwiched between the second die head 2 and the third die head 3 to form a second slit coating gap. The cavity of the die head flow channel structure of the third die head 3 is a first cavity 61, and the cavity of the die head flow channel structure of the second die head 2 is a second cavity 62. The first cavity 61 and the second cavity 62 are relatively independent, and the two cavities can be connected to different slurry supply systems, and are structurally completely isolated. The cavity of the flow channel structure of the third mold head 3 is connected to the first slit coating gap, and the cavity of the flow channel structure of the second mold head 2 is connected to the second slit coating gap.

[0068] In this embodiment, a dual-layer die head structure is adopted. Independent slurry supply cavities are formed between the first die head 1 and the third die head 3, and between the second die head 2 and the third die head 3. The two cavities are completely isolated and do not interfere with each other, each supplying slurries with different properties, enabling simultaneous composite coating of two slurries. This structure significantly improves the die head's adaptability to slurries with different rheological properties, and is particularly suitable for dual-layer coating systems with significant functional differences or large differences in particle size distribution.

[0069] With its dual-cavity design, the die head in this embodiment can be applied to various processes such as single-layer coating, double-layer simultaneous coating, and staggered multi-segment coating, making it suitable for scenarios with special functional requirements for the layered structure of the electrode. This structure also provides greater structural compatibility for future expansion into multi-layer slurry supply and multifunctional membrane materials.

[0070] In some embodiments, the first slit coating gap is arranged horizontally, the second slit coating gap is arranged obliquely, the ends of the first slit coating gap and the second slit coating gap intersect and a coating lip 10 is provided at the intersection, so that the double-layer slurry can be coated onto the target substrate.

[0071] In some embodiments, the coating die head further includes an adjustment mechanism 8, which is disposed on the first die head 1 and / or the second die head 2, for adjusting the height of the slit coating gap to accommodate different coating thicknesses. The die head is integrally assembled and pressed with the adjustment mechanism 8 by fasteners, and the coating lip spacing, angle, etc. are fixed by factory processing; due to the pre-set flow distribution scheme, there is no need for significant adjustments during use, improving coating consistency and ease of operation.

[0072] Multiple adjustment mechanisms 8 are provided, and these mechanisms are spaced apart along the width direction of the coating die. These mechanisms can operate synchronously or independently. Synchronous operation allows for consistent adjustment of the overall height of the slit coating gap, while independent operation allows for fine-tuning of the height at different locations according to the coating width requirements, further improving coating uniformity and process adaptability.

[0073] The adjustment mechanism 8 includes an actuator 83 and an adjustment block 84. The adjustment block 84 is connected to the output end of the actuator 83 and is used to adjust the height of the slit coating gap. The actuator includes a micro motor and a transmission assembly, enabling precise position adjustment of the T-shaped adjustment block. The movement of the adjustment block 84 directly affects the height change of the slit coating gap, and its displacement accuracy determines the control accuracy of the coating thickness. The adjustment block 84 consists of multiple T-shaped adjustment blocks arranged along the length of the die lip, such as... Figure 6 As shown, each T-shaped regulating block is driven by an independent actuator.

[0074] exist Figure 5 In the structure shown, in order to further improve the consistency of the lateral surface density of the coating slurry in the lip area, adjustment mechanisms are provided at the ends of the first die head and the second upper die, namely the first adjustment mechanism 81 and the second adjustment mechanism 82.

[0075] The T-shaped adjusting block is located in the discharge area of ​​the lip, corresponding to the end of the coating channel. The actuator controls the T-shaped adjusting block to move vertically via a motor-driven transmission device, thereby adjusting the height of the local discharge channel. When the slurry flows through this area, its flow rate and local pressure drop are controlled by the position of the T-shaped adjusting block, enabling fine-tuning of the flow rate at the end and thus optimizing the lateral uniformity of the final coating surface density.

[0076] The above-mentioned coating die head is suitable for a variety of high-precision double-layer composite coating processes, especially for: simultaneous coating of double-layer functional slurry for positive and negative electrode sheets of lithium-ion batteries; it can also be used for slurry coating applications where gas needs to be supplied through dual channels and where there is a requirement for uniform surface density.

[0077] The specific working process of the above-mentioned coating die head is as follows:

[0078] After each die head enters from a single sub-channel inlet, the channels are geometrically distributed in a "one-to-two, two-to-four, four-to-eight" pattern until eight symmetrically distributed channels enter their respective cavity areas. This structure is precision-machined in one piece and cannot be adjusted, but the uniform flow distribution is ensured through a layout of equal area and equal spacing. Figure 2 As shown, the slurry first enters the main cavity from the flow channel and is spread out. Due to the symmetrical distribution of the flow channels and the shortened leveling path, the pressure drop of the slurry inside the cavity is low and the distribution is uniform, which is beneficial to improving the consistency of the initial surface density.

[0079] The two layers of slurry are leveled in the first and second chambers respectively, and finally converge at the coating lip, achieving composite coating through synchronous extrusion via a slit. The final coating lip can be finely adjusted using an adjustment device to compensate for minute deviations, but since initial consistency is guaranteed, the adjustment amount is minimal and the response is rapid. Figure 5 As shown.

[0080] In practical applications, to adapt to coating requirements with small widths and few channels, the coating die can be adopted as follows: Figure 5 The diagram shows a one-outlet-four-channel structure. This structure features a relatively short overall length of the coating die head and four outlet channels, making it suitable for small-batch production and applications requiring high coating precision.

[0081] On the other hand, to meet the coating requirements of multiple widths and multiple channels, the coating die head can also adopt, for example... Figure 3 The diagram shows a 16-channel structure. This coating die integrates 16 independent discharge channels while maintaining overall rigidity, making it suitable for high-capacity coating scenarios with multiple channels operating simultaneously, offering higher efficiency and adaptability.

[0082] According to an embodiment of the present invention, in a third aspect, a coating apparatus is provided, including a coating die and a feeding system, wherein the feeding system is connected to the coating die and is used to deliver slurry to the die flow channel structure of the coating die.

[0083] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A die flow channel structure, characterized by, include: At least one cavity (6) for containing and guiding slurry; At least one feed channel (7) for feeding slurry into the cavity (6); A multi-stage symmetrical flow-dividing structure (9) is provided, with each stage of the symmetrical flow-dividing structure (9) positioned between the regions from the feed channel (7) to the cavity (6). Each symmetrical flow-dividing structure (9) includes at least one sub-channel (91), each sub-channel (91) having a sub-channel inlet (911) and two sub-channel outlets (912). The sub-channel inlet (911) of the first-stage symmetrical flow-dividing structure (9) is connected to the feed channel (7), while the sub-channel outlet (912) located away from the first-stage symmetrical flow-dividing structure is connected to the feed channel (7). The inlet (911) of the sub-channel of the symmetrical diversion structure is connected to the outlet (912) of the sub-channel of the previous symmetrical diversion structure. All the outlets (912) of the sub-channel of the last symmetrical diversion structure are connected to the cavity (6). The two outlets (912) of each sub-channel (91) are symmetrically distributed about the inlet (911) of the sub-channel of that sub-channel (91). The outlets (912) of each sub-channel of the same symmetrical diversion structure are arranged at equal intervals.

2. The die flow channel structure of claim 1 wherein, The number of sub-flow channels (91) of each stage of the symmetric split-flow structure is twice the number of the symmetric split-flow structure of the previous stage, and the last stage of the symmetric split-flow structure forms 2 n sub-flow channel discharge ports (912), wherein n is the number of split stages, and n≥2.

3. The die flow channel structure of claim 1 wherein, The distance between the two sub-channel outlets (912) of the sub-channel (91) located in the previous level is twice the distance between the two sub-channel outlets (912) of the sub-channel (91) located in the next level.

4. The die flow channel structure of claim 1 wherein, The sub-channel (91) includes: A transverse distribution channel (914) is in the same transverse direction as the cavity (6), and the sub-channel inlet (911) is located in the middle of the transverse distribution channel (914). Two longitudinal distribution channels (915) are respectively set at both ends of the transverse distribution channel (914) and connected to the transverse distribution channel (914). The longitudinal distribution channels (915) are in the same longitudinal direction as the cavity (6). The end of each longitudinal distribution channel (915) is connected to the corresponding sub-channel outlet (912).

5. A coating die characterized by, include: First mold head (1); Second mold head (2); A gasket is disposed between the first mold head (1) and the second mold head (2); The first die head (1) or the second die head (2) is provided with a die head flow channel structure as described in any one of claims 1-4. The gasket forms a slit coating gap with the first die head (1) or the second die head (2). The slit coating gap is connected to the cavity (6). The slit coating gap is used to uniformly coat the slurry flowing through the die head flow channel structure onto the target substrate.

6. The coating die of claim 5, wherein, Also includes: The third mold head (3) is disposed between the first mold head (1) and the second mold head (2); The gasket comprises a first gasket (4) and a second gasket (5), the first die (1) and the third die (3) sandwich the first gasket (4) and form a first slot coating gap, the second die (2) and the third die (3) sandwich the second gasket (5) and form a second slot coating gap, the second die (2) and the third die (3) are provided with die channel structures, the cavity of the die channel structure of the second die (2) is independent of the cavity of the die channel structure of the third die (3), the cavity of the die channel structure of the third die (3) is communicated with the first slot coating gap, and the cavity of the die channel structure of the second die (2) is communicated with the second slot coating gap.

7. The coating die of claim 6, wherein The first slot coating gap is horizontally arranged, the second slot coating gap is obliquely arranged, the end of the first slot coating gap intersects with the end of the second slot coating gap, and a coating lip (10) is arranged at the intersection.

8. The coating die of any one of claims 5-7, wherein, Further comprising: An adjusting mechanism (8) is arranged on the first die (1) and / or the second die (2) and is used for adjusting the height of the slot coating gap to adapt to the requirement of different coating thickness.

9. The coating die of claim 8, wherein, The adjusting mechanism (8) is arranged in multiple, the multiple adjusting mechanisms (8) are distributed along the width direction of the coating die, and the multiple adjusting mechanisms (8) are synchronously operated or independently operated. The adjusting mechanism (8) comprises an executing mechanism (83) and an adjusting block (84), the adjusting block (84) is connected with the output end of the executing mechanism (83) and is used for adjusting the height of the slot coating gap.

10. A coating apparatus characterized by comprising: The coating die comprises any one of claims 5-9. The coating die comprises any one of claims 5-9.

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