An asymmetric metal mesh flow field for an alkaline electrolyzer and an alkaline electrolyzer

Abstract

The present invention relates to an asymmetric metal mesh flow field for an alkaline electrolyzer. The metal mesh flow field is a circular mesh structure, the lower end of which is connected to an alkali liquid flow channel through a first radial hole flow channel, and the upper end of which is connected to a gas-liquid flow channel through a second radial hole flow channel; the metal mesh flow field is divided into three regions. The first region is a fan-shaped region located in the lower half of the circular mesh structure, and the first radial hole flow channel is located at the center of the arc segment of the first region; the second region is a fan-shaped region in the upper half of the circular mesh structure, and the second radial hole flow channel is located at the center of the arc segment of the second region; the third region includes two fan-shaped regions between the first region and the second region. Compared with the prior art, the longitudinal interference and transverse interference of the grids in different regions of the present invention are different, which increases the directional disturbance of the alkali liquid in the electrolysis unit, improves the flow dispersion of the alkali liquid and the uniformity of the flow field distribution, and significantly reduces the differences in current density and cooling environment in different reaction regions of the coronal plane of each electrolysis unit.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic hydrogen production, and more particularly to an asymmetric metal mesh flow field for an alkaline electrolyzer and an alkaline electrolyzer. Background Art

[0002] In the context of the current world's energy structure dominated by fossil fuels, hydrogen energy is widely regarded as a powerful competitor to reverse the energy situation due to its advantages such as high calorific value and zero emissions. Currently, among its various main preparation methods, hydrogen production by electrolysis of water has become the research focus of various countries due to its clean and efficient advantages. The technology of hydrogen production by electrolysis of water at room temperature is mainly divided into alkaline water electrolysis for hydrogen production AWE, proton exchange membrane electrolysis for hydrogen production PEM, and anion exchange membrane electrolysis for hydrogen production AEM operating at room temperature according to the type of electrolyte. Among them, the alkaline water electrolysis technology is the most mature, has the lowest cost and is more economical, and is considered the main method for large-scale application of hydrogen production by electrolysis of water.

[0003] As Figure 1 shown, alkaline electrolyzers used industrially are usually divided into monopolar and bipolar types according to their electrode connection methods. Among them, the latter is widely favored due to its compact structure and high energy utilization rate. The currently most commonly used filter press bipolar alkaline electrolyzer has the advantages of a compact structure, high electrolysis efficiency, and a simple gas-liquid circulation flow channel structure. Each individual electrolysis unit consists of a cell frame, a main plate, anode and cathode plates, a gas barrier diaphragm, and gaskets. Gas-liquid flow channels for the flow of hydrogen and oxygen, alkali liquid flow channels, and radial hole flow channels connecting between electrolysis units are provided on the cell frame. The alkali liquid in the alkali liquid flow channel enters the plate channel through the radial hole flow channel, then flows out from the radial hole flow channel and converges in the gas-liquid flow channel. The gas-liquid flow channel and the alkali liquid flow channel are respectively connected to the external system pipelines.

[0004] The main problem existing when using a filter press electrolyzer is the energy power consumption. During the process of electrolytic hydrogen production, more than 92% of this power consumption comes from the cell body. Since the liquid electrolyte exists as a reactant in the alkaline electrolyzer on the one hand and also serves as a cooling medium for the working cell body on the other hand, whether its flow distribution is uniform directly affects the distribution of the electrolyte in the reaction flow channel and the heat dissipation of the electrolyzer. Therefore, excluding factors such as materials, the flow channel structure of the electrolyzer is the main factor affecting energy consumption. It not only determines the flow state of the electrolyte and the product gas in the cell, the current density distribution, and the heat dissipation capacity, but also relates to the efficiency of hydrogen production by electrolysis of water and affects the long-term stable operation of the equipment. Therefore, a reasonable design of the electrolyzer plate flow channel is of great significance to the working performance and life of the alkaline electrolyzer.

[0005] Currently, circular nickel mesh flow fields are often used in industrial-scale alkaline electrolyzers as the reaction area for alkaline solutions. This reaction area has the advantages of simple structure, low cost, easy assembly, and easy preparation. However, due to the fact that the circular inner cross-sectional area first increases and then decreases as the liquid moves radially and the flow disturbance of the mesh, the fluid flows concentrated in the middle area when flowing in the upper half, and there is a large difference in the flow velocity of the alkaline solution between the inner and outer sides. As a result, the temperature and current distribution on the electrode surface are severely uneven, which will significantly affect the performance and lifespan of the electrolyzer. Therefore, it is very necessary to improve the characteristics of this uneven flow field.

[0006] In the prior art, the research on the flow field of electrolyzers is mainly limited to the improvement of rectangular internal flow fields and circular straight-channel flow field plates (Chinese patent applications "Electrolyzer Flow Field Plate Structure" with publication number CN113249746A and "Water Inlet Method of a Proton Exchange Membrane Water Electrolyzer" with publication number CN115341241A). However, there is currently no effective optimization strategy for circular mesh flow fields woven with metals such as nickel. Summary of the Invention

[0007] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide an asymmetric metal mesh flow field for alkaline electrolyzers and an alkaline electrolyzer.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] According to the first aspect of the present invention, an asymmetric metal mesh flow field for an alkaline electrolyzer is provided. The metal mesh flow field is a circular mesh structure, and its lower end is connected to the alkaline solution flow channel through the first radial hole flow channel, and its upper end is connected to the gas-liquid flow channel through the second radial hole flow channel;

[0010] The metal mesh flow field is divided into three regions. The first region is a fan-shaped region located in the lower half of the circular mesh structure, and the first radial hole flow channel is located at the center of the arc segment of the first region; the second region is a fan-shaped region in the upper half of the circular mesh structure, and the second radial hole flow channel is located at the center of the arc segment of the second region; the third region includes two fan-shaped regions between the first region and the second region;

[0011] The mesh of the metal mesh in the first region adopts a mesh with stronger longitudinal interference than transverse interference. The mesh of the metal mesh in the third region adopts a mesh with weaker longitudinal interference than transverse interference. The longitudinal interference of the mesh of the metal mesh in the second region is weaker than that of the mesh of the metal mesh in the first region and stronger than that of the mesh of the metal mesh in the third region. The transverse interference of the mesh of the metal mesh in the second region is stronger than that of the mesh of the metal mesh in the first region and weaker than that of the mesh of the metal mesh in the third region.

[0012] Preferably, the mesh of the wire mesh in the first region is diamond-shaped, with its windward angle greater than the transverse angle, the mesh of the wire mesh in the third region is diamond-shaped, with its windward angle less than the transverse angle, and the mesh of the wire mesh in the second region is diamond-shaped, with its windward angle less than the windward angle of the wire mesh in the first region and greater than the windward angle of the wire mesh in the third region, and its transverse angle is greater than the transverse angle of the wire mesh in the first region and less than the transverse angle of the wire mesh in the third region.

[0013] Preferably, the windward angle of the wire mesh in the first region is 120°, the transverse angle is 60°, the windward angle of the wire mesh in the third region is 60°, the transverse angle is 120°, the windward angle of the wire mesh in the second region is 90°, and the transverse angle is 90°.

[0014] Preferably, the mesh of the wire mesh in the boundary region between the first and second regions and the third region adopts a gradient transition design.

[0015] Preferably, the boundaries of the first region, the second region, and the third region, the mesh shape and size of the wire mesh in the first region, the mesh shape and size of the wire mesh in the second region, the mesh shape and size of the wire mesh in the third region, and the mesh shape and size of the wire mesh in the boundary region between the first and second regions and the third region are determined through simulation or experiments.

[0016] According to the second aspect of the present invention, an alkaline electrolyzer is provided, which uses the asymmetric wire mesh flow field as described in the first aspect of the present invention.

[0017] Preferably, the mesh of the wire mesh in the first region is diamond-shaped, with its windward angle greater than the transverse angle, the mesh of the wire mesh in the third region is diamond-shaped, with its windward angle less than the transverse angle, and the mesh of the wire mesh in the second region is diamond-shaped, with its windward angle less than the windward angle of the wire mesh in the first region and greater than the windward angle of the wire mesh in the third region, and its transverse angle is greater than the transverse angle of the wire mesh in the first region and less than the transverse angle of the wire mesh in the third region.

[0018] Preferably, the windward angle of the wire mesh in the first region is 120°, the transverse angle is 60°, the windward angle of the wire mesh in the third region is 60°, the transverse angle is 120°, the windward angle of the wire mesh in the second region is 90°, and the transverse angle is 90°.

[0019] Preferably, the mesh of the wire mesh in the boundary region between the first and second regions and the third region adopts a gradient transition design.

[0020] Preferably, the boundaries of the first region, the second region, and the third region, the mesh shape and size of the wire mesh in the first region, the mesh shape and size of the wire mesh in the second region, the mesh shape and size of the wire mesh in the third region, and the mesh shape and size of the wire mesh in the junction region between the first and second regions and the third region are determined through simulation or experiments.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] It increases the directional perturbation of the alkali solution in the electrolysis cell, improves the flow dispersion of the alkali solution and the uniformity of the flow field distribution, significantly reduces the differences in current density and cooling environment in different reaction regions of the coronal plane of each electrolysis cell, and thus improves the electrolysis efficiency and service life of the pressure filter type alkaline electrolyzer. Description of the Drawings

[0023] Figure 1 : a) is a schematic diagram of the monopolar type, and b) is a schematic diagram of the bipolar type;

[0024] Figure 2 : a) is a schematic diagram of the flow field partition, and b) is an example diagram of the meshes of the three regions;

[0025] Figure 3 : a) is a schematic diagram of the flow field distribution before improvement; b) is a schematic diagram of the flow field distribution after improvement;

[0026] Figure 4 : Schematic diagram of the electrolysis cell structure of the alkaline electrolyzer;

[0027] Reference numerals in the drawings: 1. Pole frame, 2. Radial hole flow channel; 3. Gasket, 4. Anode mesh, 5. Gas barrier diaphragm, 6. Gas-liquid flow channel, 7. Main pole plate, 8. Cathode mesh, 9. Alkali solution flow channel. Detailed Embodiments

[0028] The present invention will be described in detail below with reference to the drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments, and the protection scope of the present invention is not limited to the following embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] In the accompanying drawings, components with the same structure are denoted by the same numerical labels, and components with similar structures or functions everywhere are denoted by similar numerical labels. The dimensions and thicknesses of each component shown in the drawings are arbitrarily illustrated, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustration clearer and show the mating relationship between various components, the components are appropriately scaled and the distances between the components are increased or decreased in some places in the drawings.

[0030] In the description of the embodiments of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationships in which the product of this application is usually placed during use, or the orientation or positional relationships commonly understood by those skilled in the art. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0031] In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0032] In the description of the embodiments of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0033] The present invention provides an asymmetric metal mesh flow field for an alkaline electrolyzer. The metal mesh flow field is a circular mesh structure. Its lower end is connected to an alkaline solution flow channel through a first radial hole flow channel, and its upper end is connected to a gas-liquid flow channel through a second radial hole flow channel. The metal mesh flow field is divided into three regions. The first region is a fan-shaped region located in the lower half of the circular mesh structure, and the first radial hole flow channel is located at the center of the arc segment of the first region. The second region is a fan-shaped region in the upper half of the circular mesh structure, and the second radial hole flow channel is located at the center of the arc segment of the second region. The third region includes two fan-shaped regions between the first region and the second region. The mesh of the metal mesh in the first region uses a mesh with stronger longitudinal interference than transverse interference. The mesh of the metal mesh in the third region uses a mesh with weaker longitudinal interference than transverse interference. The longitudinal interference of the mesh of the metal mesh in the second region is weaker than that of the mesh of the metal mesh in the first region and stronger than that of the mesh of the metal mesh in the third region. The transverse interference of the mesh of the metal mesh in the second region is stronger than that of the mesh of the metal mesh in the first region and weaker than that of the mesh of the metal mesh in the third region.

[0034] As Figure 2 shown, for the circular mesh flow field structure, the alkaline solution flows in from below and will be disturbed under the action of the complex mesh structure, so as to spread out over a large area and finally cover the entire flow field coronal plane. At the same time, the alkaline solution will also undergo oxidation-reduction reactions on the surface of the metal mesh under the action of the input current, generating hydrogen, oxygen and heat. The low-temperature alkaline aqueous solution moderately cools this place. In this process, water is consumed, and the alkaline solution and gas flow out from the outlet (upper), and the electrolysis system continues to work.

[0035] Therefore, as Figure 2 shown in a), according to the flow law and interference idea, the flow field region of this application can be simply divided into four regions A, B, C, and D. The arrows in the figure indicate the flow direction of the alkaline solution. Among them, region A is the first region of this application, region D is the second region of this application, and regions B and C are the third regions of this application. Of course, it can be understood that Figure 2 the uniform four regions A, B, C, and D shown in are only for illustration and do not represent the actual three-region division. In fact, due to the complexity of the flow field and flow, how to divide the first region and the second region from the third region can be determined through simulation or actual experiments.

[0036] The flow rate of the alkaline solution in the inlet region A (the first region) is relatively fast, and it is difficult to be distributed to both sides of the flow channel under the action of inertia. Therefore, the main interference target here is to reduce the flow rate and increase the diffusion to both sides. Thus, a mesh with stronger longitudinal interference is used as the flow channel guide in the first region. Here, a mesh with a large longitudinal windward angle and a small transverse angle can be used. Under the action of this mesh, the fluid near the inlet is strongly longitudinally blocked and moves to both sides under the guidance of the nickel wire, entering regions B and C;

[0037] The fluid in regions B and C (the third region) is mostly vortex fluid diffused from near the midline. In the conventional flow field distribution, it has the characteristics of small mass distribution and low energy. Therefore, in order to increase the distribution ratio of this region, a grid with weak longitudinal interference needs to be used as the flow channel guide in this region. Here, a grid with a small longitudinal windward angle and a large lateral angle can be used. When the fluid flowing upward under the action of such a grid, the longitudinal resistance it receives is very small, and the energy loss is less under weak longitudinal disturbances. Therefore, the movement speed will not decrease too much.

[0038] Region D (the second region) converges the lye from regions A, B, and C. At this time, the overall fluid kinetic energy is lower than that in region A but still higher than that in regions B and C. The purpose of the flow field design in this region is to guide the fluid from regions A, B, and C to flow out with less blockage. Therefore, for the lye coming from both sides, a grid with small resistance is used, and at the same time, the resistance to the longitudinally flowing lye is reduced. A grid with both a small longitudinal windward angle and a small lateral angle can be used. Under the action of such a grid, the fluid from regions B and C receives a smaller lateral resistance compared to that within this region. Therefore, the already dispersed lye is more likely to converge and enter D. The high-speed fluid from region A has already had a significant speed loss under the action of a grid with large longitudinal resistance. After entering region D, the longitudinal resistance it receives is greatly reduced, enabling it to maintain a sufficient flow rate to leave the circular flow field.

[0039] In order to make the flow field design more reasonable, the grid of the wire mesh at the junction of the first region, the second region, and the third region adopts a gradient transition design. For example, in the junction area of the first region near the third region, the windward angle can be continuously reduced, and so on. In fact, the boundaries of the three regions, the grid shape of each region, the size of the grid of each region, as well as the grid shape and size of the junction region can all be regarded as variables to be determined. Through simulation or experiment, determine the boundaries of the first region, the second region, the third region, the grid shape and size of the wire mesh in the first region, the grid shape and size of the wire mesh in the second region, the grid shape and size of the wire mesh in the third region, and the grid shape and size of the wire mesh at the junction of the first region, the second region, and the third region.

[0040] As Figure 2 As shown in b), the grid of the wire mesh in the first region is diamond-shaped, its windward angle is greater than the lateral angle. The grid of the wire mesh in the third region is diamond-shaped, its windward angle is less than the lateral angle. The grid of the wire mesh in the second region is diamond-shaped, its windward angle is less than the windward angle of the wire mesh in the first region and greater than the windward angle of the wire mesh in the third region, and its lateral angle is greater than the lateral angle of the wire mesh in the first region and less than the lateral angle of the wire mesh in the third region.

[0041] In the embodiments of the present application, to facilitate the description of the differences in the grid of three regions of the present application, the windward angle of the metal mesh grid in the first region is set to 120°, the transverse angle is 60°, the windward angle of the metal mesh grid in the third region is 60°, the transverse angle is 120°, the windward angle of the metal mesh grid in the second region is 90°, and the transverse angle is 90°. The metal mesh is woven with nickel wires, the diameter of the nickel wires is 250 μm, the grid shape is diamond-shaped, the side length is 0.5 mm, the overall diameter D of the metal mesh is 150 mm, and the flow field height (which can be understood as the thickness of the metal mesh) h is 1 mm. In actual implementation, the definition of its specific shape, size, angle, etc. can be determined by means of theoretical calculation, simulation analysis, and experiments according to the actual lye flow rate and the expected flow field distribution.

[0042] Before and after the improvement of the flow field structure, the flow field distribution of the lye in the metal mesh flow field is as Figure 3 shown. The arrows in the figure indicate the flow direction of the lye. It can be seen that in the improved metal mesh flow field, the flow dispersion of the lye and the uniformity of the flow field distribution are improved.

[0043] Compared with the prior art, without significantly modifying the plate mesh structure, the present invention combines the blocking effects of the diamond-shaped mesh structure and the outer surface of the nickel wire at different angles, resulting in different longitudinal and transverse interferences of the grids in different regions, increasing the directional disturbance of the lye in the electrolysis unit, improving the flow dispersion of the lye and the uniformity of the flow field distribution, significantly reducing the differences in the current density and cooling environment of different reaction regions on the coronal plane of each electrolysis unit, thereby achieving the improvement of the electrolysis efficiency and service life of the filter-press alkaline electrolyzer. In addition, while ensuring a more uniform distribution of the flow field, the present application also makes the velocity differences between regions not too large, reducing the kinetic energy loss caused by the velocity gradient between fluids.

[0044] The present invention also provides an alkaline electrolyzer using the above asymmetric metal mesh flow field. Among them, the schematic diagram of the electrolysis unit structure of the alkaline electrolyzer is as Figure 4 shown, including a pole frame 1, a gasket 3, an anode mesh 4, a gas barrier diaphragm 5, a cathode mesh 8, a main plate 7, etc. Among them, the pole frame 1 is used to fix the electrolysis unit and restrain other components; the anode mesh 4 is the anode reaction interface and is used to construct the flow field; the cathode mesh 8 is the cathode reaction interface and is used to construct the flow field; the main plate 7 is the main reaction interface and is used to construct the flow field; the gas barrier diaphragm 5 is used for sealing and separating the anode and cathode; the lye flow channel 9 is an axial lye channel; the gas-liquid flow channel 6 is an axial lye and gas channel; the gasket 3 is mainly used for the sealing structure.

[0045] The bipolar frame 1 is a quasi-circular column structure, and radial hole flow channels 2 for the inflow and outflow of lye and the circulation of product gas (i.e., hydrogen and oxygen) are provided on both the upper and lower sides. The lye enters the plate channel through the lye flow channel 9 and the radial hole flow channel 2, and then flows out from the radial hole flow channel 2 and converges in the gas-liquid flow channel 6. The gas-liquid flow channel 6 and the lye flow channel 9 are respectively connected to the external system pipelines. The anode mesh 4 and the cathode mesh 8 are circular mesh structures, which are used to form the internal structure of the flow field and serve as the reaction catalytic interface. During actual assembly, they are welded to the inner side of the bipolar frame 1. The asymmetric metal mesh flow field proposed above is to improve the mesh structures of the anode mesh 4 and the cathode mesh 8.

[0046] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. An asymmetric metal mesh flow field for an alkaline electrolyzer, Characterized in that, The metal mesh flow field is a circular mesh structure, the lower end of which is connected to the alkaline liquid flow channel through the first radial hole flow channel, and the upper end of which is connected to the gas-liquid flow channel through the second radial hole flow channel; The metal mesh flow field is divided into three regions. The first region is a fan-shaped region located in the lower half of the circular mesh structure, and the first radial hole flow channel is located at the center of the arc segment of the first region; the second region is a fan-shaped region in the upper half of the circular mesh structure, and the second radial hole flow channel is located at the center of the arc segment of the second region; the third region includes two fan-shaped regions between the first region and the second region; The mesh of the metal mesh in the first region has stronger longitudinal interference than transverse interference, the mesh of the metal mesh in the third region has weaker longitudinal interference than transverse interference, the longitudinal interference of the mesh of the metal mesh in the second region is weaker than that of the mesh of the metal mesh in the first region and stronger than that of the mesh of the metal mesh in the third region, and the transverse interference of the mesh of the metal mesh in the second region is stronger than that of the mesh of the metal mesh in the first region and weaker than that of the mesh of the metal mesh in the third region.

2. An asymmetric metal mesh flow field for an alkaline electrolyzer according to claim 1, Characterized in that, The mesh of the metal mesh in the first region is diamond-shaped, its windward angle is greater than the transverse angle, the mesh of the metal mesh in the third region is diamond-shaped, its windward angle is less than the transverse angle, the mesh of the metal mesh in the second region is diamond-shaped, its windward angle is less than the windward angle of the mesh of the metal mesh in the first region and greater than the windward angle of the mesh of the metal mesh in the third region, and its transverse angle is greater than the transverse angle of the mesh of the metal mesh in the first region and less than the transverse angle of the mesh of the metal mesh in the third region.

3. An asymmetric metal mesh flow field for an alkaline electrolyzer according to claim 2, Characterized in that, The windward angle of the mesh of the metal mesh in the first region is 120°, the transverse angle is 60°, the windward angle of the mesh of the metal mesh in the third region is 60°, the transverse angle is 120°, and the windward angle of the mesh of the metal mesh in the second region is 90°, and the transverse angle is 90°.

4. An asymmetric metal mesh flow field for an alkaline electrolyzer according to claim 1, Characterized in that, The mesh of the metal mesh in the boundary regions between the first region and the second region and the third region adopts a gradient transition design.

5. An asymmetric metal mesh flow field for an alkaline electrolyzer according to claim 1, Characterized in that, The boundaries of the first region, the second region, and the third region, the mesh shape and size of the metal mesh in the first region, the mesh shape and size of the metal mesh in the second region, the mesh shape and size of the metal mesh in the third region, and the mesh shape and size of the metal mesh in the boundary regions between the first region and the second region and the third region are determined by simulation or experiment.

6. An alkaline electrolyzer, Characterized in that, It uses the asymmetric metal mesh flow field described in claim 1.

7. An alkaline electrolyzer according to claim 6, Characterized in that, The mesh of the wire mesh in the first region is diamond-shaped, and its windward angle is greater than the lateral angle. The mesh of the wire mesh in the third region is diamond-shaped, and its windward angle is less than the lateral angle. The mesh of the wire mesh in the second region is diamond-shaped, and its windward angle is less than the windward angle of the wire mesh in the first region and greater than the windward angle of the wire mesh in the third region, and its lateral angle is greater than the lateral angle of the wire mesh in the first region and less than the lateral angle of the wire mesh in the third region.

8. An alkaline electrolytic cell according to claim 7, characterized in that the windward angle of the mesh of the wire mesh in the first region is 120°, the lateral angle is 60°, the windward angle of the mesh of the wire mesh in the third region is 60°, the lateral angle is 120°, and the windward angle of the mesh of the wire mesh in the second region is 90°, and the lateral angle is 90°.

9. An alkaline electrolytic cell according to claim 6, characterized in that the mesh of the wire mesh in the boundary region between the first region and the second region and the third region adopts a gradual transition design.

10. An alkaline electrolytic cell according to claim 9, characterized in that the boundaries of the first region, the second region, and the third region, the mesh shape and size of the wire mesh in the first region, the mesh shape and size of the wire mesh in the second region, the mesh shape and size of the wire mesh in the third region, and the mesh shape and size of the wire mesh in the boundary region between the first region and the second region and the third region are determined by simulation or experiment.

Images