A bipolar plate for a fuel cell

Abstract

The present invention relates to a bipolar plate for a fuel cell, comprising a core module, a peripheral module, and a plurality of connection modules. The core module is provided with a flow field unit, the peripheral module is a frame structure, and the core module is mounted inside the frame structure via a plurality of connection modules. The outer edge of the core module, the inner edge of the peripheral module, and the connection module form a plurality of hollow structures, some of which serve as gas or liquid channels for the fuel cell. The connection module comprises a first connection portion and a second connection portion, the first connection portion connecting the outer edge of the core module and the second connection portion connecting the inner edge of the peripheral module, and the first connection portion and the second connection portion are detachably connected to each other. Compared with the prior art, the present invention can achieve the flexibility and insulation requirements of the fuel cell stack design, improve the product's scope of application, reduce modification and manufacturing costs, and facilitate subsequent changes and maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a bipolar plate for a fuel cell. Background Art

[0002] A proton exchange membrane fuel cell is an electrochemical device that uses a catalyst to decompose hydrogen at the anode into protons and electrons. The protons reach the cathode through the proton exchange membrane, and the electrons reach the cathode through an external circuit. The electrons, protons and oxygen generate water under the catalysis of the cathode catalyst. It has the advantages of high efficiency, low temperature, cleanliness and environmental protection.

[0003] The structure of a proton exchange membrane fuel cell can be divided into an active part that reacts and releases energy, and a reactive part that does not react and releases energy. The reactive part includes structures such as fluid distribution and sealing, and is an essential component for the active part to realize its function.

[0004] Existing proton exchange membrane fuel cells typically use a single bipolar plate, which contains both the active and reactive components. This structure presents the following issues: 1. A single bipolar plate must meet both the corrosion resistance and electrical conductivity requirements of the active component and the sealing and insulation requirements of the reactive component, which increases the overall plate manufacturing process requirements. 2. The single-plate production method cannot achieve flexible matching of different flow field designs and distributed sealing structure designs for various application scenarios. 3. Direct contact between the bipolar plate and the housing is prone to leakage, posing a safety hazard. Summary of the Invention

[0005] The purpose of the present invention is to provide a bipolar plate for a fuel cell in order to overcome the defects of the prior art.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A bipolar plate for a fuel cell comprises a core module, a peripheral module and a plurality of connection modules, wherein the core module is provided with a flow field unit, the peripheral module is a frame structure, and the core module is installed inside the frame structure through a plurality of connection modules; the outer edge of the core module, the inner edge of the peripheral module and the connection module form a plurality of hollow structures, and some of the hollow structures are gas channels or liquid channels of the fuel cell; the connection module comprises a first connection part and a second connection part, the first connection part connects the outer edge of the core module, and the second connection part connects the inner edge of the peripheral module, and the first connection part and the second connection part are detachably connected to each other.

[0008] Furthermore, a protrusion or a groove is provided on the end of the first connecting part, and a groove or a protrusion corresponding to the first connecting part is provided on the end of the second connecting part, and the groove and the protrusion are embedded in each other to form a connection.

[0009] Furthermore, the joints between the protrusions and the grooves are coated with sealing glue.

[0010] Furthermore, the protrusion and the groove are connected by interference fit.

[0011] Furthermore, the peripheral module is provided with a stack sealing structure. When the bipolar plates and membrane electrode in the fuel cell are stacked at intervals, the stack sealing structures on adjacent bipolar plates are connected to each other to form an overall seal.

[0012] Furthermore, the peripheral module is made of engineering plastic plate or rubber plate.

[0013] Furthermore, the peripheral module is provided with a positioning pin installation hole.

[0014] Furthermore, the core module is made of an integrally formed metal plate or graphite composite plate.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] 1. The present invention integrates the active area (flow field unit) in the bipolar plate into the core module, the reactive area into the peripheral module, and then combines the core module and the peripheral module through a connecting module to form a new design structure; it only needs to design different peripheral modules for different types of fuel cell stacks and match the same core module, so that the same flow field can be used in stacks of different power levels; it is also possible to replace the core module in one type of fuel cell stack to achieve different flow field designs; it effectively improves the applicable power range of the bipolar plate and realizes the design flexibility of the stack.

[0017] 2. The core module and the peripheral module can be manufactured using different materials, which can not only improve the corrosion resistance and conductivity requirements of the reaction area, but also improve the functional requirements of the sealing and insulation of the reactive part. At the same time, it reduces the manufacturing process difficulty and cost, and facilitates later changes and maintenance.

[0018] 3. The connecting module forms a hollow structure between the core module and the peripheral module. The hollow structures at both ends naturally form gas channels or liquid channels for the fuel cell. The hollow structures on both sides can effectively isolate the core module from the outside, thereby better protecting against leakage.

[0019] 4. A stack sealing structure is provided on the peripheral module. When the bipolar plates and membrane electrode in the fuel cell are stacked at intervals, a closed whole is formed between the bipolar plates, achieving the best insulation and sealing effect.

[0020] 5. Positioning pin mounting holes are provided on the peripheral module to facilitate the installation and positioning of the bipolar plate in the fuel cell housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention.

[0022] Figure structure: 1. Core module, 2. Peripheral module, 21. Positioning pin mounting hole, 3. Connection module, 31. First connection part, 32. Second connection part, 4. Hollow structure. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0024] like Figure 1 As shown, this embodiment provides a bipolar plate for a fuel cell, comprising a core module 1, a peripheral module 2, and multiple connection modules 3. The peripheral module 2 is a frame structure, and the core module 1 is mounted within the frame structure via multiple connection modules 3. A flow field unit is provided on the core module 1, which is a component used for the reaction operation of the fuel cell stack.

[0025] The outer edge of the core module 1, the inner edge of the peripheral module 2, and the connection module 3 form multiple hollow structures 4. The hollow structures 4 on the left and right ends of the core module 1 serve as gas or liquid channels for the fuel cell. The hollow structures 4 on the upper and lower sides of the core module 1 form an isolation layer between the core module 1 and the peripheral modules 2, effectively isolating the core module 1 from the outside world and providing better protection against leakage.

[0026] Each connection module 3 includes a first connection part 31 and a second connection part 32. The first connection part 31 is connected to the outer edge of the core module 1, and the second connection part 32 is connected to the inner edge of the peripheral module 2. The first connection part 31 and the second connection part 32 are detachably connected to each other. In this embodiment, there are three types of connection modules 3, which are respectively shown as A, B, and C in the figure. In the B-type connection module 3, a protrusion is provided on the end of the first connection part 31, and a groove is provided on the end of the second connection part 32. The protrusion on the first connection part 31 and the groove on the second connection part 32 are fitted together to form a connection, and a sealing glue is applied at the fitting part. In the A-type connection module 3, the protrusion on the end of the first connection part 31 is T-shaped, and is connected with the groove on the second connection part 32 by interference fit, making the connection easier to disassemble, repair or replace. In the C-type connection module 3, the protrusion on the end of the first connection part 31 and the groove on the second connection part 32 are both L-shaped and fit into each other; the C-type connection module 3 is located at the corners of the core module 1, which can improve the connection strength of the first connection part 31 and the second connection part 32.

[0027] The peripheral module 2 is provided with a stack sealing structure. When the bipolar plates and membrane electrode in the fuel cell are stacked in intervals, the stack sealing structures on adjacent bipolar plates are interconnected to form an overall seal. The stack sealing structure adopts a traditional sealing structure, including but not limited to the glue dispensing / injection area and the mounting glue line sealing groove. The outermost sealing structure is continuous, completely isolating the core plate module and having excellent insulation performance. The peripheral module 2 is also provided with a positioning pin mounting hole 21 to facilitate the installation and positioning of the bipolar plate in the fuel cell housing.

[0028] The peripheral module 2 can be made of engineering plastic plate or rubber plate, and its manufacturing process can be directly injection-molded onto the core module 1, or it can be assembled with the core module 1 through offline processing.

[0029] The core module 1 may be made of a metal material integrally formed by rolling or stamping, or may be made of a graphite composite material by molding or machining. In this embodiment, an integrally formed metal plate is used.

[0030] In this embodiment, the active area of the bipolar plate is integrated into the core module 1, the reactive area is integrated into the peripheral module 2, and then the core module 1 and the peripheral module 2 are combined through the connecting module 3 to form a new design structure.

[0031] When in use, it is only necessary to design different peripheral modules 2 for different types of fuel cell stacks and match them with the same core module 1, so that the same flow field can be used in stacks of different power levels; it is also possible to replace the core module 1 in one type of fuel cell stack to achieve different flow field designs; effectively improve the applicable power range of the bipolar plate and realize the design flexibility of the stack.

[0032] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. A bipolar plate for a fuel cell, characterized in that: The invention comprises a core module (1), a peripheral module (2) and a plurality of connection modules (3), wherein the core module (1) is provided with a flow field unit, the peripheral module (2) is a frame structure, and the core module (1) is installed inside the frame structure through the plurality of connection modules (3); the outer edge of the core module (1), the inner edge of the peripheral module (2) and the connection module (3) form a plurality of hollow structures (4), the hollow structures (4) located at the left and right ends of the core module (1) are gas channels or liquid channels of the fuel cell, and the hollow structures (4) located at the upper and lower sides of the core module (1) form an isolation layer between the core module (1) and the peripheral module (2); the connection module (3) comprises a first connection part (31) and a second connection part (32), the first connection part (31) is connected to the outer edge of the core module (1), and the second connection part (32) is connected to the inner edge of the peripheral module (2), and the first connection part (31) and the second connection part (32) are detachably connected to each other; The peripheral module (2) is provided with a stack sealing structure. When the bipolar plates and membrane electrodes in the fuel cell are stacked at intervals, the stack sealing structures on adjacent bipolar plates are connected to each other to form an integral seal. The peripheral module (2) is provided with a positioning pin mounting hole (21).

2. A bipolar plate for a fuel cell according to claim 1, characterized in that: The end of the first connecting portion (31) is provided with a protrusion or a groove, and the end of the second connecting portion (32) is provided with a groove or a protrusion corresponding to the first connecting portion (31), and the groove and the protrusion are interlocked to form a connection.

3. A bipolar plate for a fuel cell according to claim 2, characterized in that: Sealing glue is applied to the joints between the protrusions and the grooves.

4. A bipolar plate for a fuel cell according to claim 2, characterized in that: The projections and grooves are connected by interference fit.

5. The bipolar plate for a fuel cell according to claim 1, characterized in that: The peripheral module (2) is made of an engineering plastic plate or a rubber plate.

6. The bipolar plate for a fuel cell according to claim 1, characterized in that: The core module (1) is made of an integrally formed metal plate or graphite composite plate.

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