Laboratory composite diaphragm double-sided coating device

Abstract

The utility model discloses a double-sided coating device for a laboratory composite diaphragm in the field of preparation of composite diaphragms for hydrogen production by alkaline electrolysis of water. The double-sided coating device comprises a sliding assembly, a base material, a diaphragm scraping assembly, a base material fastening assembly and a handle, according to the utility model, the problems of performance distortion and incapability of adapting to casting membrane solutions with different viscosities are solved; according to the utility model, through a synchronous double-sided coating mechanism, the performance distortion is avoided, and meanwhile, the industrial environment is directly simulated, so that the amplification of laboratory data is improved; an unnecessary roller system structure is removed, so that the size and the cost of equipment are reduced, the cleaning and maintenance time is shortened, and the experiment efficiency is improved; in addition, the coating device can adapt to the casting membrane liquid with various viscosities, the coating uniformity of the casting membrane liquid with different viscosities is ensured through the design that the stainless steel scraper is matched with the fixed included angle, meanwhile, the flow speed of the casting membrane liquid is accurately controlled through the design that the flat plate type discharging groove is matched with the adjustable damping hinge, and the coating defect caused by viscosity difference is avoided.

Description

Technical Field

[0001] This utility model relates to the field of composite membrane preparation for alkaline water electrolysis to produce hydrogen, specifically a laboratory composite membrane double-sided coating device. Background Technology

[0002] In the alkaline water electrolysis hydrogen production process, the membrane, as a core component, serves to separate the anode and cathode, prevent hydrogen and oxygen from mixing, and allow ions to migrate through the electrolyte. High-performance membranes need to meet a series of stringent requirements, including high mechanical strength, excellent gas tightness and ionic conductivity, and good chemical stability in alkaline environments over long periods. Traditional organic polymer membranes are limited by their poor alkali resistance, while inorganic membranes, although possessing good chemical stability, have relatively weak mechanical properties. Therefore, composite membranes combining the advantages of organic and inorganic materials have gradually become a research hotspot. Composite membranes utilize an inorganic substrate for mechanical support, combined with a polymer coating to achieve excellent gas barrier and ion conduction properties, showing broad application prospects.

[0003] The industrial preparation of composite membranes typically employs a double-sided coating process. This method allows for the simultaneous and uniform coating of polymer molecules onto both sides of the substrate, improving membrane uniformity and pore structure consistency, thereby significantly enhancing the overall performance of the composite membrane. However, industrial double-sided coating equipment usually utilizes roller coating devices. The substrate is wound and unwound using rollers, and the slurry is coated onto the continuously moving substrate by a doctor blade. This system is a continuous coating technology, characterized by high efficiency, stability, and suitability for large-scale production. However, its disadvantages include being limited by the roller structure, resulting in a large, complex, and expensive device, which is extremely inconvenient for small-scale laboratory research and testing.

[0004] Existing small-scale coating equipment is mostly a scaled-down version of industrial equipment, with no fundamental change in its working mechanism. Even equipment for preparing small-sized diaphragms remains large and expensive, requiring significant amounts of casting solution, substrate, and coagulation bath for each preparation. Subsequent cleaning and maintenance also require considerable time and manpower, making it unsuitable for laboratory use. In the research and development of composite diaphragms, laboratories typically choose the simplest single-sided coating device (flatbed + blade coater). However, due to differences in coating processes between experimental and industrial equipment, scale-up production often fails to achieve the performance expected in the laboratory. Therefore, developing compact, laboratory-grade double-sided coating equipment and optimizing composite diaphragm preparation processes for industrial scale-up are crucial for advancing the research and application of alkaline water electrolysis diaphragm materials.

[0005] For example, the patent number CN202223124861.X discloses a "small coating device for all-solid-state soft-pack batteries". This device places foil on a holding rack and fixes it by clamping it with a first frame and a second frame. Then, a scraper is placed on a guide rail that is parallel to each other on the first frame and the second frame through a partition. The scraper is then moved along the guide rail to achieve coating. The above assembly and coating process is repeated to obtain a double-sided symmetrically coated electrode sheet.

[0006] For example, the patent CN115911249 discloses a "double-sided coating method based on wet coating and sliding wire rod". This method involves applying a wet coating to the surface of the battery electrode, then using a wire rod for single-sided coating, and finally flipping the substrate to repeat the coating operation on the other side. A feeler gauge is used to control the coating thickness, thus completing the double-sided coating. However, this method is mainly suitable for battery electrodes with flat and dense surfaces. It is not suitable for porous substrates (such as PPS screens) because during single-sided coating, the casting solution penetrates to the back of the substrate, causing an uneven back surface and making it difficult to flip and recoat.

[0007] Therefore, double-sided coating equipment for battery electrodes often employs a method of coating one side first and then the other. However, in reality, due to differences in the substrates used, this method of coating both sides sequentially cannot be applied to the preparation of composite separators. Therefore, small-scale laboratory double-sided coating equipment or methods, whether scaled down from industrial coating equipment for composite separators or not suitable for laboratory use, are not suitable for laboratory applications.

[0008] Currently, researchers in universities, enterprises, and research institutions typically use a simple single-sided coating method to prepare composite membranes in the laboratory. While this method is simple in equipment and convenient in operation, and allows for flexible adjustment of substrate size and casting solution volume according to experimental needs, especially in small-scale trials where it can quickly screen for promising membrane formulations, it still has a significant drawback: the performance of the prepared composite membrane differs from that of membranes prepared under industrial double-sided coating conditions. This difference can lead to the membrane optimized in the laboratory failing to achieve the expected performance in large-scale production.

[0009] Therefore, the existing technology mainly suffers from performance distortion and inability to adapt to casting solutions of different viscosities. Utility Model Content

[0010] The purpose of this invention is to provide a laboratory composite diaphragm double-sided coating device to solve the problems of performance distortion and inability to adapt to casting solutions of different viscosities mentioned in the background art.

[0011] To achieve the above objectives, this utility model provides the following technical solution: a laboratory composite diaphragm double-sided coating device, comprising a sliding component, a substrate, a film scraping component, a substrate fastening component, and a handle;

[0012] The sliding assembly, the film scraping assembly, the substrate fastening assembly, and the handle are each provided in two sets, and are arranged in a completely mirror-symmetrical manner on both sides of the substrate;

[0013] The sliding assembly includes two sets of parallel linear guides and two sets of sliders, with the sliders slidably connected to the linear guides;

[0014] The film scraping assembly includes a scraper, a flat feed trough, and an adjustable damping hinge. The long side of the non-blade side of the scraper is fixedly connected to the side of the corresponding slider. The flat feed trough is rotatably mounted on the inside of the scraper through the adjustable damping hinge. The flat feed trough can be suspended at any angle through the adjustable damping hinge.

[0015] The handle has two sets, which are nested on the two sets of sliders respectively;

[0016] The substrate fastening assembly includes two sets of parallel metal brackets, which are arranged perpendicularly to and fixedly connected to the linear guide rail.

[0017] The substrate is detachably mounted between two sets of substrate fastening assemblies arranged in a completely mirror-symmetrical manner.

[0018] Preferably, the two sets of sliders are provided with protruding hangers at the same height on their sides, and the handle is provided with a handle groove. The shape of the handle groove is adapted to the protruding hanger to form a rigid connection structure.

[0019] Preferably, the handle groove extends through the handle, and the protruding hanging parts on the sliders on one side of the two sets of sliding components are nested together in the handle groove.

[0020] Preferably, the substrate fastening assembly includes two sets of parallel-arranged fastening bolts and nuts, rubber strips, openings, and metal brackets.

[0021] Preferably, two sets of rubber strips are fixedly connected in the middle of two sets of parallel metal brackets, and the substrate is detachably installed between the rubber strips of the two sets of substrate fastening components.

[0022] Preferably, the opening is set on the metal bracket, and the fastening bolts and nuts are installed at both ends of the opening, and the substrate and the metal bracket are fixedly connected by the fastening bolts and nuts.

[0023] Preferably, the angle formed by the scraper and the side of the slider is the same as the angle between the scraper and the substrate when scraping the film, and is 30° to 60°.

[0024] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention solves the problem of inability to coat porous substrates in stages due to permeation through a synchronous double-sided coating mechanism, avoiding performance distortion. It also directly simulates the industrial environment, improving the scalability of laboratory data. Furthermore, by eliminating unnecessary roller structures, it reduces equipment size and cost, decreases cleaning and maintenance time, and improves experimental efficiency. In addition, this invention can adapt to casting solutions of various viscosities. The stainless steel scraper combined with a fixed angle design ensures uniform coating of casting solutions of different viscosities. Simultaneously, the combination of a flat feed trough and an adjustable damping hinge enables precise control of the casting solution flow rate, avoiding coating defects caused by viscosity differences. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the components of this utility model;

[0027] Figure 2 This is a disassembly diagram of one side of the present invention;

[0028] Figure 3 This is a schematic diagram of the scraping film assembly structure of this utility model;

[0029] Figure 4 This is a schematic diagram of the working operation of the movable feeding trough of this utility model.

[0030] 1. Sliding assembly; 11. Linear guide rail; 12. Slider; 13. Protruding hanger; 2. Substrate; 3. Coating assembly; 31. Coating blade; 32. Flat feed chute; 33. Adjustable damping hinge; 4. Substrate fastening assembly; 41. Fastening bolts and nuts; 42. Rubber strip; 43. Opening; 44. Metal bracket; 5. Handle; 51. Handle groove. Detailed Implementation

[0031] 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 protection scope of the present utility model.

[0032] One embodiment of this utility model:

[0033] like Figures 1-4 As shown, the double-sided coating device includes a sliding assembly 1, a substrate 2, a scraping assembly 3, a substrate fastening assembly 4, and a handle 5. The sliding assembly 1, scraping assembly 3, substrate fastening assembly 4, and handle 5 are arranged in two sets, perfectly mirror-symmetrically on both sides of the substrate 2. The sliding assembly 1, substrate fastening assembly 4, and scraping assembly 3 can be connected and combined by welding, bolting, snap-fitting, or mechanical locking.

[0034] The sliding assembly 1 includes two sets of parallel linear guide rails 11 and two sets of sliders 12. Each set of linear guide rails 11 is equipped with a set of sliders 12. The sliders 12 can perform linear reciprocating motion on the linear guide rails 11. At the same time, both sets of sliders 12 have protruding hangers 13 welded at the same height on the side. The handle 5 is provided with a handle groove 51. The protruding hangers 13 are adapted to the handle groove 51 of the handle 5 and form a rigid connection structure. They are used to embed into the handle groove 51 to fix the handle 5, ensuring that the handle 5 forms a reliable connection with the sliding assembly 1 during operation, and at the same time achieving smooth and precise sliding control.

[0035] Meanwhile, the handle groove 51 extends through the handle 5 and can simultaneously accommodate the protruding hangers 13 of the sliders 12 on one side of both sets of sliding components 1. When the handle 5 is pushed or pulled in the sliding direction, the sliders 12 of the two symmetrically arranged sliding components 1 move synchronously through the engagement of the protruding hangers 13 with the handle groove 51. This causes the scraper 31 fixed on the slider 12 to also move synchronously, ensuring the synchronicity and consistency of the two-sided scraping components 3 during the coating process.

[0036] The film-coating assembly 3 includes a scraper 31, a flat feed trough 32, and an adjustable damping hinge 33. The scraper 31 is elongated, and its non-blade side is fixedly connected to the sides of two sets of sliders 12 at the same height via welding, bolting, snap-fit, or mechanical locking. The angle formed between the scraper 31 and the sides of the sliders 12 is the same as the angle between the scraper 31 and the substrate 2 during film coating, and is between 30° and 60°. The scraper 31 can be a coating machine scraper, a fabric cutter blade, a heavy-duty cutting machine blade, or a long strip blade used for slitting in the food / pharmaceutical industry. It is suitable for coating high-viscosity casting solutions, preventing deformation, and is preferably made of stainless steel for easy cleaning. Adjustable damping hinges 33 are provided at both ends of the two sets of scrapers 31. The flat plate feed trough 32 is rotatably mounted on the inner side of the two sets of scrapers 31 via the adjustable damping hinges 33. When the angle between the flat plate feed trough 32 and the scraper 31 is 0°, the flat plate feed trough 32 is attached to the inner surface of the scraper 31. Furthermore, the flat plate feed trough 32 can be suspended at any angle via the adjustable damping hinges 33. Therefore, during use, the angle between the flat plate feed trough 32 and the scraper 31 can be adjusted according to the viscosity of the casting liquid in the trough, thereby controlling the speed at which the casting liquid flows to the substrate 2. Specifically, for casting liquids with low viscosity and good fluidity, the angle can be reduced to slow down the flow rate, while for casting liquids with high viscosity and poor fluidity, the angle can be increased to accelerate the flow. Furthermore, in the case where the casting liquid gradually decreases and the flow slows down during the coating process, the angle between the flat plate feed trough 32 and the scraper 31 can be increased at any time during the coating process to ensure that the slurry flows to the substrate 2 at a uniform speed throughout the entire coating process. Compared with the fixed feed trough, the movable feed trough can reduce the loss of casting liquid.

[0037] The substrate fastening assembly 4 includes two sets of parallel-arranged metal brackets 44, rubber strips 42, and fastening bolts and nuts 41. The metal brackets 44 are high-strength, long strip-shaped metal parts, such as angle steel, flat steel, or H-beams. Next, the rubber strips 42 are horizontally fixed to the middle of the metal brackets 44 by adhesive bonding, snap-fitting, or pinning. The rubber strips 42 are made of long, elastic material with high friction, and their length is approximately 1 / 2 to 1 / 3 of the length of the metal brackets 44, used to clamp the substrate 2. Subsequently, symmetrical openings 43 are provided on both sides of the metal brackets 44 at the positions where the rubber strips 42 are fixed, for stable positioning of the substrate 2. Furthermore, the fastening bolts and nuts 41 are installed in the openings 43, stably connecting the substrate 2 to the metal brackets 44.

[0038] Meanwhile, two sets of metal brackets 44 are arranged perpendicularly to the linear guide rail 11. The two are connected to each other by welding, bolting, snap-fitting or mechanical locking to form a rectangular frame structure.

[0039] First, the substrate 2 needs to be selected. Take a 200μm thick 50-mesh polyphenylene sulfide (PPS) mesh and cut it to a length of 50cm and a width of 20cm. Then, place the cut PPS mesh on one side of the double-sided coating device, lay the PPS mesh flat, and align its two ends with the rubber strips 42 at both ends of the double-sided coating device. Then, cover the other side of the double-sided coating device onto the PPS mesh and align it with the one side of the bottom double-sided coating device through the opening 43 on the metal bracket 44, forming a sandwich arrangement. Finally, clamp and fix the PPS mesh in the middle of the double-sided coating device through the opening 43 using four sets of fastening bolts and nuts 41, ensuring that the PPS mesh remains straight during the tightening of the fastening bolts and nuts 41.

[0040] Next, the coating thickness is set. After the double-sided coating device is erected, the sliders 12 on both sides of the polyphenylene sulfide (PPS) mesh, along with the squeegees 31, are pushed to the bottom of the linear guide rail 11. In this embodiment, the designed coating thickness is 500 μm. Since the PPS mesh itself is 200 μm thick, the narrowest distance between the blades of the two squeegees 31 and the PPS mesh is 150 μm. A 100 μm thick feeler gauge is inserted between the blades of the squeegees 31 and the PPS mesh, and the distance between the blades of the squeegees 31 and the PPS mesh is precisely controlled to 150 μm by tightening the fastening bolts and nuts 41.

[0041] Next comes the coating process. According to the required coating width, an appropriate amount of casting solution is poured evenly from both sides of the polyphenylene sulfide (PPS) mesh within the V-shaped angle formed by the scraper 31. During pouring, it is ensured that the casting solution is evenly distributed on both sides of the PPS mesh, and the amount of casting solution on both sides is kept as consistent as possible. The handle 5 is used for coating. Holding the handles 5 on both sides, the scraper assembly 3 moves upward at a constant speed. During this movement, the scraper 31 simultaneously coats both sides of the PPS mesh. The handle 5 slowly and evenly rises from the bottom of the linear guide rail 11 to the top of the linear guide rail 11, and the scraper 31 gradually coats the entire surface of the mesh with the casting solution, forming a continuous coating layer. Finally, the four sets of fastening bolts and nuts 41 on the metal bracket 44 are loosened, and the coated composite diaphragm is pulled out and removed from the double-sided coating device, thus completing the coating process.

[0042] Finally, after coating is complete, all detachable components must be disassembled in sequence. To ensure the long-term stable use of the device, before storage, wipe the surface with a cloth dampened with ethanol, isopropanol, or a special cleaning solution to remove any casting solution residue. Then rinse with deionized water, wipe dry with a paper towel or soft dry cloth, and place in an oven to dry. After drying, store and organize all components.

[0043] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0044] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A laboratory composite separator double sided coating apparatus characterized by: It comprises a sliding assembly (1), a base material (2), a film scraping assembly (3), a base material fastening assembly (4) and a handle (5); The sliding assembly (1), the film scraping assembly (3), the base material fastening assembly (4) and the handle (5) are both provided with two groups and are arranged completely in mirror image on both sides of the base material (2); The sliding assembly (1) comprises two groups of parallel linear guides (11) and two groups of sliding blocks (12), and the sliding blocks (12) are slidingly connected to the linear guides (11); The film scraping assembly (3) comprises a doctor blade (31), a flat plate type blanking groove (32) and an adjustable damping hinge (33), the non-blade side long edge of the doctor blade (31) is fixedly connected to the side of the corresponding sliding block (12), the flat plate type blanking groove (32) is rotatably installed on the inner side of the doctor blade (31) through the adjustable damping hinge (33), and the flat plate type blanking groove (32) can be arbitrarily suspended at any angle through the adjustable damping hinge (33); The handle (5) is provided with two groups, which are respectively nested on the two groups of sliding blocks (12); The base material fastening assembly (4) comprises two groups of parallel metal supports (44), which are arranged perpendicularly to the linear guides (11) and are fixedly connected; The base material (2) is detachably installed between the two groups of completely mirror image arranged base material fastening assemblies (4).

2. A laboratory composite separator double sided coating apparatus as claimed in claim 1, wherein: The side surfaces of the two groups of sliding blocks (12) are provided with protruding hanging pieces (13) at the same height, the handle (5) is provided with a handle groove (51), the shape of the handle groove (51) is matched with that of the protruding hanging pieces (13), and a rigid connection structure is formed.

3. A laboratory composite separator double sided coating apparatus as claimed in claim 2, wherein: The handle groove (51) penetrates the handle (5), and the protruding hanging pieces (13) on the sliding blocks (12) of the two groups of sliding assemblies (1) are nested in the handle groove (51) together.

4. The laboratory composite separator double sided coating apparatus of claim 1, wherein: The base material fastening assembly (4) comprises two groups of parallel fastening bolts and nuts (41), rubber strips (42), holes (43) and metal supports (44).

5. The laboratory composite separator double sided coating apparatus of claim 3, wherein: The two groups of rubber strips (42) are fixedly connected to the middle parts of the two groups of parallel metal supports (44), and the base material (2) is detachably installed between the rubber strips (42) of the two groups of base material fastening assemblies (4).

6. A laboratory composite separator double sided coating apparatus as claimed in claim 3, wherein: The holes (43) are arranged on the metal supports (44), the fastening bolts and nuts (41) are installed at both ends of the holes (43), and the base material (2) is fixedly connected to the metal supports (44) through the fastening bolts and nuts (41).

7. The laboratory composite separator double sided coating apparatus of claim 1, wherein: The included angle formed by the doctor blade (31) and the side surface of the sliding block (12) is the same as the included angle between the doctor blade (31) and the base material (2) during film scraping, and is 30°-60°.

Images