Bipolar plate assembly, electrolysis stack and electrolysis cell

Abstract

The application provides a bipolar plate assembly, an electrolysis stack and an electrolysis tank. By arranging a rigid rhombic net on one side of the bipolar plate and a flexible elastic net on the other side, the mechanical strength of the whole bipolar plate is maintained through the rhombic net, the stability and durability of the equipment during long-term operation are ensured, the close adhesion with the electrode is realized through the self-adaptive deformation ability of the elastic net, the interface gap is significantly reduced, the zero-polar-distance state is maximally approached, the contact resistance is reduced, the current conduction efficiency is improved, and the electrolysis efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the technical field of water electrolysis hydrogen production equipment, and in particular to a bipolar plate assembly, an electrolytic stack, and an electrolytic cell. Background Technology

[0002] In existing electrolytic cell designs, bipolar plates typically employ a rigid rhombic mesh structure with symmetrical anode and cathode sides to achieve conductivity, support, and reactant distribution. However, due to the rigidity of the rhombic mesh and manufacturing assembly tolerances, it is difficult to form a completely tight contact with the electrode surface, generally resulting in a gap of 10-100 micrometers. This gap leads to a significant increase in interfacial contact resistance, thereby increasing the operating voltage and energy consumption of the electrolytic cell. Although the industry generally pursues "zero-gap" to reduce ohmic losses, traditional rigid mesh structures, due to physical limitations, have always been unable to completely eliminate the gap and achieve "zero-gap."

[0003] In theory, zero electrode gap requires complete contact between the electrode and the bipolar plate (gap ≤ 1 micrometer). However, in practical engineering, this goal is extremely difficult to achieve due to limitations in material deformation capacity, surface flatness, and long-term operational stability. Existing improvement solutions (such as elastic conductive pads and foam metal layers) can reduce the gap to 5-20 micrometers, but overly soft elastic materials are prone to contact pressure attenuation due to compression creep, resulting in a sacrifice of mechanical strength or durability.

[0004] Therefore, there is an urgent need for a bipolar plate assembly that can meet the zero-pole-gap requirement while ensuring the mechanical strength of the overall structure. Utility Model Content

[0005] The purpose of this application is to provide a bipolar plate assembly, an electrolytic stack, and an electrolytic cell that can meet the zero-pole gap requirement while ensuring the mechanical strength of the overall structure.

[0006] To achieve the above objectives, in a first aspect, this application provides a bipolar plate assembly, comprising a bipolar plate, at least one rhomboid mesh, an elastic mesh, a first electrode, and a second electrode:

[0007] The bipolar plate includes a bipolar plate body and an electrode frame fixedly disposed on the outer periphery of the bipolar plate body. The electrode frame and a first side of the bipolar plate body enclose a first small chamber, and the electrode frame and a second side of the bipolar plate body enclose a second small chamber.

[0008] The diamond-shaped mesh is disposed in the first small chamber, and the first electrode covers the diamond-shaped mesh and is fixedly connected to the electrode frame;

[0009] The elastic mesh is disposed in the second small chamber, and the second electrode covers the elastic mesh and is fixedly connected to the electrode frame.

[0010] In this way, by setting a rigid diamond mesh on one side of the bipolar plate and an elastic mesh on the other side, the diamond mesh maintains the overall mechanical strength of the bipolar plate, ensuring the stability and durability of the equipment in long-term operation; while the elastic mesh achieves close contact with the electrodes through its adaptive deformation capability, significantly reducing the interface gap and approaching the zero electrode distance state as closely as possible, thereby reducing contact resistance, improving current conduction efficiency, and improving electrolysis efficiency.

[0011] Optionally, the bipolar plate assembly further includes at least one conductive component;

[0012] The conductive component is fixedly connected to the first side of the bipolar plate body and divides the first small chamber into several sub-electrolysis chambers;

[0013] Multiple diamond-shaped meshes are respectively installed in each sub-electrolysis chamber;

[0014] The first electrode is also fixedly connected to the conductive component.

[0015] Optionally, the conductive component has an elongated strip structure.

[0016] Optionally, the height of the conductive component is greater than or equal to the height of the diamond mesh.

[0017] Optionally, the materials of the conductive components include, but are not limited to, pure nickel, nickel-based alloys, nickel-plated stainless steel, pure titanium, and titanium-based alloys.

[0018] Optionally, the elastic mesh and the second electrode are an integral structure.

[0019] Optionally, the diamond-shaped mesh is a fish-scale-shaped metal mesh.

[0020] Optionally, the first chamber is a cathode chamber, and the second chamber is an anode chamber;

[0021] The first electrode is a cathode electrode, and the second electrode is an anode electrode.

[0022] Secondly, embodiments of this application provide an electrolytic reactor, the electrolytic reactor including the bipolar plate assembly described above; the electrolytic reactor further includes:

[0023] A sealing gasket is located between any two bipolar plate assemblies.

[0024] Thirdly, embodiments of this application provide an electrolytic cell, which includes the bipolar plate assembly described above, or the electrolytic stack described above. Attached Figure Description

[0025] Figure 1a This is one of the structural schematic diagrams of the bipolar plate assembly provided in the embodiments of this application;

[0026] Figure 1b This is a second schematic diagram of the structure of the bipolar plate assembly provided in the embodiments of this application;

[0027] Figure 2a This is a schematic diagram of the structure of the bipolar plate provided in an embodiment of this application;

[0028] Figure 2b A front view of a bipolar plate is provided for an embodiment of this application;

[0029] Figure 2c A cross-sectional view of a bipolar plate is provided for an embodiment of this application;

[0030] Figure 3 A schematic diagram of an integral elastic mesh electrode provided in an embodiment of this application;

[0031] Figure 4 A schematic diagram illustrating a connection method between an elastic mesh and a second electrode, provided in an embodiment of this application;

[0032] Figure 5 This is the third schematic diagram of the bipolar plate assembly provided in the embodiments of this application;

[0033] Figure 6a A schematic diagram of the connection between the conductive rib and the bipolar plate body provided in an embodiment of this application;

[0034] Figure 6b A top view showing the connection between the conductive rib and the bipolar plate body provided in an embodiment of this application;

[0035] Figure 7a One of the schematic diagrams of a conductive component connected to a bipolar plate body according to an embodiment of this application;

[0036] Figure 7b A second schematic diagram showing the conductive component connected to the bipolar plate body according to an embodiment of this application;

[0037] Figure 8a This is one of the structural schematic diagrams of a diamond mesh, conductive components and bipolar plate body combined according to an embodiment of this application;

[0038] Figure 8b One of the enlarged partial views of a diamond mesh, conductive component and bipolar plate body combined according to an embodiment of this application;

[0039] Figure 8c A second schematic diagram of the structure of a diamond mesh, conductive components and bipolar plate body combined according to an embodiment of this application;

[0040] Figure 8dA second enlarged partial view of a diamond mesh, conductive component and bipolar plate body combined according to an embodiment of this application;

[0041] Figure 9a This is a schematic diagram of an electrolytic reactor provided in an embodiment of this application;

[0042] Figure 9b A cross-sectional schematic diagram of two bipolar plate assemblies stacked together is provided for an embodiment of this application;

[0043] Figure 10 This is a schematic diagram of the structure of an electrolytic cell provided in an embodiment of this application;

[0044] The reference numerals in the attached figures are explained as follows:

[0045] 1-Bipolar plate assembly; 11-Bipolar plate; 111-Bipolar plate body; 112-Electrode frame; 113-First chamber; 1131-Sub-electrolysis chamber; 114-Second chamber; 115-Gas flow channel hole; 116-Liquid flow channel hole; 12-Rhomboid mesh; 13-Elastic mesh; 14-First electrode; 15-Second electrode; 16-Conductive component; 2-Electrolytic stack; 21-Sealing gasket; 22-Diaphragm; 3-Electrolytic cell. Detailed Implementation

[0046] To make the objectives, advantages, and features of this application clearer, the electrolytic cell proposed in this application will be further described in detail below with reference to the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the purpose of illustrating the embodiments of this application.

[0047] To facilitate understanding of this application, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected to" another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," "inner," "outer," and similar expressions used in this specification are for illustrative purposes only. In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of indicated technical features. Thus, unless otherwise stated, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. The term "comprising" and any variations thereof mean non-exclusive inclusion, where one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0048] Furthermore, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection via an intermediate medium, or a connection within two components. All technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0049] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0050] refer to Figure 1a and Figure 1b , Figure 1a This is one of the structural schematic diagrams of the bipolar plate assembly provided in the embodiments of this application. Figure 1b This is a second schematic diagram of the structure of the bipolar plate assembly provided in the embodiments of this application. The bipolar plate assembly 1 may include a bipolar plate 11, at least one rhomboid mesh 12, an elastic mesh 13, a first electrode 14, and a second electrode 15.

[0051] Among them, reference Figures 2a to 2c , Figure 2a This is a schematic diagram of the structure of the bipolar plate provided in an embodiment of this application. Figure 2b A front view of a bipolar plate is provided for an embodiment of this application. Figure 2c This application provides a cross-sectional view of a bipolar plate. The bipolar plate 11 may include a bipolar plate body 111 and an electrode frame 112 fixedly disposed on the outer periphery of the bipolar plate body 111. The electrode frame 112 and a first side of the bipolar plate body 111 enclose a first chamber 113, and the electrode frame 112 and a second side of the bipolar plate body 111 enclose a second chamber 114. The first chamber 113 may be the anode chamber or the cathode chamber in a water electrolysis hydrogen production system. Similarly, the second chamber 114 may be an electrolysis chamber with the opposite polarity to the first chamber 113. That is, when the first chamber 113 is the anode chamber, the second chamber 114 is the cathode chamber, and when the first chamber 113 is the cathode chamber, the second chamber 114 is the anode chamber.

[0052] The bipolar plate 11 may also be provided with a gas flow channel 115 and a liquid flow channel 116, wherein the gas flow channel 115 is located in the upper part of the electrode frame 112, and the liquid flow channel 116 is located in the lower part of the electrode frame 112. The electrolyte solution enters the anode chamber and the cathode chamber through the liquid flow channel 116. In the anode chamber, an electrolytic reaction generates oxygen and its gas-liquid mixture, and in the cathode chamber, an electrolytic reaction generates hydrogen and its gas-liquid mixture. The generated oxygen and its gas-liquid mixture, and hydrogen and its gas-liquid mixture, can be discharged through the gas flow channel 115.

[0053] It should be noted that this application does not impose specific limitations on the number and layout of gas flow channel holes 115 and liquid flow channel holes 116. Those skilled in the art can determine the number and layout of gas flow channel holes 115 and liquid flow channel holes 116 based on experience and actual needs.

[0054] Furthermore, the first chamber 113 can be preferentially configured as an anode chamber, and the second chamber 114 can be preferentially configured as a cathode chamber; correspondingly, the first electrode 14 is an anode electrode, and the second electrode 15 is a cathode electrode.

[0055] The diamond-shaped mesh 12 can be disposed within the first chamber 113, and the diamond-shaped mesh 12 can specifically be a fish-scale-shaped metal mesh. Further, the diamond-shaped mesh 12 within the first chamber 113 can be a single mesh, such as... Figure 1a As shown, a single rhombus mesh is arranged within the first chamber 113; alternatively, there can be multiple rhombus meshes 12 within the first chamber 113, such as... Figure 1b As shown, multiple diamond-shaped meshes are arranged together in the first small chamber 113.

[0056] The first electrode 14 can cover the diamond mesh 12 and be fixedly connected to the electrode frame 112. There are various ways to fix it, such as welding or gluing, and no specific method is limited.

[0057] The elastic mesh 13 can be set in the second chamber 114. The elastic mesh 13 can be an elastic support made of metal wire (such as pure nickel wire) by bending, spiraling, winding, etc. It can adapt to the small deformation inside the electrolytic cell and ensure close contact between the electrode and the plate, thus extending the service life.

[0058] The second electrode 15 can be placed on the elastic mesh 13 and fixedly connected to the electrode frame 112. There are various ways to fix it, such as welding or gluing, and no specific method is limited.

[0059] Furthermore, the elastic mesh 13 and the second electrode 15 can also be an integral structure. Figure 1a or Figure 1b The elastic mesh 13 shown is different from the second electrode 15, which are separate structures, as shown in the figure. Figure 3The diagram shown is a structural schematic of an integrated elastic mesh electrode provided in an embodiment of this application. The elastic mesh 13 and the second electrode 15 can be pre-connected to form an integrated structure.

[0060] There are several ways to pre-connect the elastic mesh 13 to the second electrode 15. In one example, it can be as follows: Figure 4 The diagram shows a connection method between an elastic mesh and a second electrode according to an embodiment of this application. A metal wire 131 passes through the downward-facing side of the second electrode 15 and extends on the upward-facing side of the second electrode 15. Then, it passes through the upward-facing side of the second electrode 15 again and extends on the downward-facing side of the second electrode 15. This process is repeated multiple times to connect the elastic mesh 13 and the second electrode 15. The metal wire 131 can be any metal wire in the elastic mesh 13 or a different metal wire from the elastic mesh 13. The specific method is not limited.

[0061] In other examples, the elastic mesh 13 and the second electrode 15 can also be pre-connected by means such as adhesive bonding or welding. Those skilled in the art can choose different methods based on experience or actual conditions, and no specific limitation is made.

[0062] In this way, by setting a rigid diamond mesh on one side of the bipolar plate and an elastic mesh on the other side, the diamond mesh maintains the overall mechanical strength of the bipolar plate, ensuring the stability and durability of the equipment in long-term operation; while the elastic mesh achieves close contact with the electrodes through its adaptive deformation capability, significantly reducing the interface gap and approaching the zero electrode distance state as closely as possible, thereby reducing contact resistance, improving current conduction efficiency, and improving electrolysis efficiency.

[0063] Considering Figure 1a and Figure 1b The diamond mesh 12 is directly pressed between the bipolar plate 11 and the first electrode 14. Due to the possible microscopic unevenness or assembly errors on the surfaces of the bipolar plate 11 and the first electrode 14, the diamond mesh 12 cannot ensure that every local area of ​​the first electrode 14 is in close contact. Poor contact in the area will lead to a decrease in the current conduction efficiency, which in turn affects the uniformity of the electrolysis reaction and reduces the overall hydrogen production efficiency.

[0064] Based on the above problems, the embodiments of this application address... Figure 1b The bipolar plate assembly 1 shown in the figure has been improved, such as... Figure 5 The third schematic diagram of the bipolar plate assembly provided in the embodiments of this application shows that the bipolar plate assembly may further include at least one conductive component 16.

[0065] refer to Figure 6a and Figure 6b ,in, Figure 6aThis is a schematic diagram of the connection between the conductive rib and the bipolar plate body provided in an embodiment of this application. Figure 6b This is a top view showing the connection between the conductive rib and the bipolar plate body provided in an embodiment of this application. The conductive component 16 can be fixedly connected to the first side of the bipolar plate body 111 and divide the first chamber 113 into several sub-electrolysis chambers 1131.

[0066] Furthermore, the conductive component 16 can be fixedly connected to the bipolar plate body 111 along the height direction of the bipolar plate body 111. In the case of multiple conductive components 16, in one example, such as Figure 7a The diagram shown is one of the schematic diagrams illustrating the connection of the conductive component to the bipolar plate body according to an embodiment of this application. Figure 7a Yes Figure 6b The enlarged example shown in the figure shows that each conductive component 16 can be arranged in parallel on the bipolar plate body 111, that is, there is only one conductive component 16 along the height direction of the bipolar plate body 111.

[0067] In another example, such as Figure 7b The image shown is a second schematic diagram illustrating the connection of the conductive component provided in this application to the bipolar plate body. Figure 7b Yes Figure 6b In another example shown in the magnified view of region B, each conductive component 16 can be sequentially and fixedly connected to the bipolar plate body 111 along its length direction. That is, there can be multiple conductive components 16 along the height direction of the bipolar plate body 111. Furthermore, after the conductive components 16 are arranged sequentially along their length direction to form a conductive component assembly, the conductive component assemblies are then arranged parallel to each other on the bipolar plate body 111. Figure 6b The structure shown.

[0068] In this embodiment, the conductive component 16 can be an elongated structure. In addition, one or more channels can be formed on the conductive component 16 through openings or grooves, and the electrolyte solution can flow between the sub-electrolysis chambers 1131 through the channels.

[0069] Furthermore, the materials of the conductive component 16 include, but are not limited to, pure nickel, nickel-based alloys, nickel-plated stainless steel, pure titanium, and titanium-based alloys.

[0070] Furthermore, the rhomboid mesh 13 can be disposed within the sub-electrolysis chamber 1131, as shown in the reference. Figures 8a to 8d , Figure 8a This is one of the schematic diagrams of the structure of a diamond mesh, conductive components, and bipolar plate body combined according to an embodiment of this application. Figure 8b This is one of the enlarged partial views of a diamond mesh, conductive component, and bipolar plate body combined according to an embodiment of this application. Figure 8cThis is the second schematic diagram of the structure of a diamond mesh, conductive components, and bipolar plate body combined according to an embodiment of this application. Figure 8d This is a second enlarged partial view of a diamond-shaped mesh, conductive components, and a bipolar plate body assembled according to an embodiment of this application. It should be noted that... Figure 8a and Figure 8c This is a schematic diagram of the structure after combining the diamond mesh, conductive components and bipolar plate body from different angles such as top view and side view. Figure 8b Yes Figure 8a An example magnified view of region C in the middle. Figure 8d Yes Figure 8c An example magnified view of region D in the middle.

[0071] from Figure 8d As can be seen, the height of the conductive component 16 (i.e., H shown in the figure) can be less than or equal to the height of the rhombus mesh 12 (i.e., h shown in the figure). This ensures that the rhombus mesh 12 is in close contact with every local area of ​​the first electrode 14, and ensures that the first electrode 14 or the second electrode 15 has zero gap or a small negative gap with the diaphragm 22, thereby achieving a tight bond between the rhombus mesh 12 and the first electrode 14 and improving the conductivity of the interface.

[0072] Furthermore, the height difference between the conductive component 16 and the diamond mesh 12 can be within the range of 0.5 to 1.5 mm. If the height difference is too large, the surface of the first electrode 14 may not be flat enough; if the height difference is too small, the diamond mesh 12 and the first electrode 14 will not be in close contact.

[0073] Furthermore, the first electrode 14 can also be fixedly connected to the conductive component 16. There are various ways to fix it, such as welding or gluing, and there is no specific limitation.

[0074] Thus, by fixing the conductive components to the electrodes, a tight bond is achieved between the rhomboid mesh and the electrodes. This bipolar plate assembly structure completely solves the loosening problem of the rhomboid mesh caused by vibration and thermal cycling in traditional structures, ensuring a stable, low-resistance conductive connection between the electrodes and the bipolar plate body. Furthermore, this structure not only improves interfacial conductivity but also significantly enhances the uniformity of current distribution, effectively avoiding localized overheating and performance degradation. It is particularly suitable for electrolyzers used in water electrolysis for hydrogen production, requiring high power density and long lifespan.

[0075] Based on the same inventive concept, this application provides an electrolytic reactor, such as Figure 9a The diagram shown is a structural schematic of an electrolytic reactor provided in an embodiment of this application. The electrolytic reactor 2 includes the bipolar plate assembly 1 described above; the electrolytic reactor 2 also includes:

[0076] A sealing gasket 21 is located between the diaphragm 22 and the bipolar plate assembly 1.

[0077] The diaphragm 22 is located between the two bipolar plate assemblies 1.

[0078] in, Figure 9a The diagram shows only a stacked schematic of a bipolar plate assembly, a diaphragm, and a sealing gasket. The electrolytic stack 2 can be composed of multiple bipolar plate assemblies 1, multiple sealing gaskets 21, and multiple diaphragms 22 stacked together.

[0079] Figure 9b An exemplary embodiment of this application provides a cross-sectional schematic diagram of two bipolar plate assemblies stacked together, from... Figure 9b As can be seen, after any two adjacent bipolar plate assemblies 1 are stacked, the first electrode 14 of one bipolar plate assembly 1 is adjacent to the second electrode 15 of the other bipolar plate assembly 1. A diaphragm 21 is provided between the first electrode 14 and the second electrode 15, and a sealing gasket 22 is provided between the diaphragm and the second electrode of the other bipolar plate assembly 1.

[0080] Thus, in an electrolytic reactor, any two adjacent bipolar plate assemblies can maintain the overall mechanical strength of the electrolytic reactor and achieve close contact with the electrodes through the diamond mesh on one side and the elastic mesh on the other side, significantly reducing the interface gap and maximizing the approach to the zero electrode gap state, thereby reducing contact resistance, improving current conduction efficiency, and improving electrolysis efficiency.

[0081] Based on the same inventive concept, this application provides an electrolytic cell, such as... Figure 10 The diagram shown is a structural schematic of an electrolytic cell provided in an embodiment of this application. The electrolytic cell 3 includes the bipolar plate assembly 1 described above, or the electrolytic stack 2 described above.

[0082] The above description is merely a description of preferred embodiments of this application and is not intended to limit the scope of this application in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A bipolar plate assembly, characterized by Includes a bipolar plate, at least one rhomboid mesh, an elastic mesh, a first electrode, and a second electrode. The bipolar plate includes a bipolar plate body and an electrode frame fixedly disposed on the outer periphery of the bipolar plate body. The electrode frame and a first side of the bipolar plate body enclose a first small chamber, and the electrode frame and a second side of the bipolar plate body enclose a second small chamber. The diamond-shaped mesh is disposed in the first small chamber, and the first electrode covers the diamond-shaped mesh and is fixedly connected to the electrode frame; The elastic mesh is disposed in the second small chamber, and the second electrode covers the elastic mesh and is fixedly connected to the electrode frame.

2. The bipolar plate assembly of claim 1, wherein The bipolar plate assembly also includes at least one conductive component; The conductive component is fixedly connected to the first side of the bipolar plate body and divides the first small chamber into several sub-electrolysis chambers; Multiple diamond-shaped meshes are respectively installed in each sub-electrolysis chamber; The first electrode is also fixedly connected to the conductive component.

3. The bipolar plate assembly of claim 2, wherein The conductive component has a long strip-shaped structure.

4. The bipolar plate assembly of claim 2, wherein The height of the conductive component is greater than or equal to the height of the diamond mesh.

5. The bipolar plate assembly of claim 2, wherein The conductive component is made of pure nickel, nickel-based alloy, nickel-plated stainless steel, pure titanium, or titanium-based alloy.

6. The bipolar plate assembly of claim 1, wherein The elastic mesh and the second electrode are an integral structure.

7. The bipolar plate assembly of claim 1, wherein The diamond-shaped mesh is a fish-scale-shaped metal mesh.

8. The bipolar plate assembly according to any one of claims 1 to 7, characterized in that The first chamber is a cathode chamber, and the second chamber is an anode chamber; The first electrode is a cathode electrode, and the second electrode is an anode electrode.

9. An electrolysis stack, characterized in that The electrolytic reactor includes the bipolar plate assembly according to any one of claims 1 to 8; The electrolytic reactor also includes: A sealing gasket is located between any two bipolar plate assemblies.

10. An electrolytic cell characterized in that, The electrolytic cell includes a bipolar plate assembly as described in any one of claims 1 to 8, or includes an electrolytic stack as described in claim 9.

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