Graphite plate proton exchange membrane fuel cell with integrated seal

Abstract

The application discloses a graphite pole plate proton exchange membrane fuel cell integrated with sealing glue lines, and belongs to the technical field of fuel cell design. The fuel cell main body is composed of a cathode plate, a membrane electrode assembly and an anode plate which are stacked together. The pole plate is divided into an outer peripheral sealing structure area and a central gas-liquid reaction area. The gas side faces the membrane electrode, and the cooling liquid side is away from the membrane electrode. The cooling liquid sides of the anode plate and the adjacent cathode plate are integrally formed into a bipolar plate through heat curing of heat-curing sealing glue lines. The anode gas side adopts light-curing sealing glue lines, and the cathode gas side adopts a cathode sealing strip to be sealingly connected with the membrane electrode assembly, respectively. The above structure can improve the overall rigidity and sealing reliability of the electric pile, reduce the pole plate contact resistance, simplify the assembly process, avoid leakage of the gas and the cooling liquid, and improve the operation stability of the battery.

Description

Technical Field

[0001] This invention relates to the field of fuel cell design technology, and in particular to a graphite plate proton exchange membrane fuel cell with integrated adhesive line sealing. Background Technology

[0002] Existing proton exchange membrane fuel cells are mainstream clean power generation devices that rely on hydrogen energy conversion. They use hydrogen and oxygen from the air as reaction raw materials. The stack is formed by stacking and pressing anode plates, membrane electrode assemblies, and cathode plates in sequence. The anode and cathode plates are used as core structural components. The independent sealing structure between the anode and cathode plates prevents the leakage of reaction gas, and hydrogen energy can be efficiently converted into electrical energy.

[0003] However, existing proton exchange membrane fuel cells have many shortcomings in assembly and operation, including: uneven pressure distribution and high plate contact resistance during stacking; poor performance consistency and sealing reliability of individual cells within the stack; disassembly and repair of the entire stack is required when a single cell fails, making battery testing and maintenance difficult and costly; traditional stacking assembly methods are not only inefficient but also prone to problems such as poor gas sealing and leakage, failing to balance battery life, structural stability, and the economics of large-scale application. Summary of the Invention

[0004] The purpose of this invention is to provide a graphite electrode plate proton exchange membrane fuel cell with integrated sealing of adhesive lines, thereby solving the above-mentioned technical problems.

[0005] To achieve the above objectives, the present invention provides a graphite electrode proton exchange membrane fuel cell with integrated adhesive wire sealing, comprising: The fuel cell body has gas and liquid inlets and outlets at both ends, and includes a cathode plate, a membrane electrode assembly and an anode plate stacked in sequence. The cathode plate and the anode plate are respectively arranged on the cathode side and the anode side of the membrane electrode assembly. Both the cathode plate and the anode plate include an outer sealing structure area and a central gas-liquid reaction area. The side of the cathode plate and the anode plate facing the membrane electrode assembly is the gas side, and the other side is the coolant side. The coolant side of the anode plate and the coolant side of the adjacent cathode plate are pre-bonded to an integrated bipolar plate by thermosetting sealant. The gas side of the anode plate is sealed to the anode side of the membrane electrode assembly by light-curing sealant. The gas side of the cathode plate is sealed to the cathode side of the membrane electrode assembly by a cathode sealing strip.

[0006] Preferably, one end of the gas-liquid inlet and outlet includes a coolant inlet, an oxygen outlet, and a hydrogen inlet arranged at intervals, and the other end of the gas-liquid inlet and outlet includes a coolant outlet, an oxygen inlet, and a hydrogen outlet arranged at intervals.

[0007] Preferably, the membrane electrode assembly includes a proton exchange membrane coated with a catalyst, a cathode-side gas diffusion layer, an anode-side gas diffusion layer, and a frame. The proton exchange membrane is disposed inside the frame. The cathode-side gas diffusion layer and the anode-side gas diffusion layer are disposed on the cathode side and the anode side of the proton exchange membrane, respectively, and both the cathode-side gas diffusion layer and the anode-side gas diffusion layer are located in the gas-liquid reaction zone.

[0008] Preferably, the gas side of the anode plate is provided with a plurality of anode gas sealing grooves with overflow grooves. The plurality of anode gas sealing grooves are arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. The anode gas sealing grooves are sealed and bonded to the frame by the light-curing sealant line, and when curing, excess adhesive overflows into the overflow groove to achieve anode sealing. Correspondingly, the gas-liquid reaction zone is provided with an anode hydrogen distribution area with a flow guiding structure and a parallel wave-shaped anode hydrogen flow field. Both ends of the anode hydrogen flow field are connected to the hydrogen inlet and the hydrogen outlet through the anode hydrogen distribution area, respectively. The anode hydrogen distribution area and the anode hydrogen flow field are correspondingly matched with the anode-side gas diffusion layer to achieve uniform distribution and reaction transport of hydrogen.

[0009] Preferably, the anode plate has a plurality of anode coolant sealing grooves on the coolant side, and the plurality of anode coolant sealing grooves are arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. Corresponding to the gas-liquid reaction zone, there is an anode coolant distribution area with a flow guiding structure and a parallel wave-shaped anode coolant flow field. Both ends of the anode coolant flow field are connected to the coolant inlet and the coolant outlet through the anode coolant distribution area, respectively.

[0010] Preferably, the cathode plate has a cathode gas sealing groove on the gas side, which is arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. The cathode gas sealing groove is sealed to the frame by a cathode sealing strip to achieve cathode sealing. Correspondingly, the gas-liquid reaction zone has a cathode oxygen distribution area with a flow guiding structure and a parallel DC channel cathode oxygen flow field. Both ends of the cathode oxygen flow field are connected to the oxygen inlet and the oxygen outlet through the cathode oxygen distribution area, respectively. The cathode oxygen distribution area and the cathode oxygen flow field are correspondingly matched with the cathode-side gas diffusion layer to achieve uniform distribution and reaction transport of oxygen.

[0011] Preferably, the cathode sealing strip is bonded to the cathode graphite plate using an adhesive tooling. The adhesive tooling includes a tooling body, limiting blocks, and a tooling membrane. Multiple limiting blocks are arranged circumferentially around the cathode plate to limit and fix it. The cathode sealing strip is embedded in the tooling membrane. The surface of the cathode sealing strip is sprayed with sealing adhesive lines and can be attached and smoothed into the cathode gas sealing groove. After removing the tooling membrane, the cathode plate is placed in a constant temperature chamber for heat curing to achieve fixed bonding between the cathode sealing strip and the cathode gas sealing groove.

[0012] Preferably, the cathode plate has a cathode coolant sealing groove on the coolant side. The cathode coolant sealing groove is arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone and is sealed to the anode coolant sealing groove by thermosetting sealant line to achieve coolant sealing. A parallel direct-flow cathode coolant flow field is provided in the gas-liquid reaction zone. The two ends of the parallel direct-flow cathode coolant flow field are respectively connected to the coolant inlet and the coolant outlet. The cathode coolant flow field and the anode coolant flow field are distributed correspondingly to enhance coolant disturbance heat transfer.

[0013] Preferably, the sealing structure areas of the cathode plate and the anode plate, as well as the frame, are provided with corresponding assembly positioning holes. The assembly positioning holes are symmetrically arranged along the center of the frame and cooperate with the positioning rod for positioning during assembly, so as to achieve precise alignment of the cathode plate, the anode plate and the frame.

[0014] Preferably, the assembly method of the above-mentioned graphite plate proton exchange membrane fuel cell is as follows: The coolant sides of the anode and cathode plates are thermosetting to form an integrated bipolar plate via thermosetting sealant. The gas side of the anode plate and the membrane electrode assembly are bonded to the cathode plate via photocuring sealant and a cathode sealing strip to form an integrated fuel cell assembly. Then, with the aid of positioning rods, multiple fuel cell assemblies are stacked sequentially and sealed together. The cathode plate of a single fuel cell assembly is sealed to the frame of the adjacent single fuel cell assembly via a cathode sealing strip to form the main body of the fuel cell.

[0015] Therefore, the present invention, employing the above-mentioned graphite electrode plate proton exchange membrane fuel cell with integrated adhesive wire sealing and its assembly method, has the following beneficial effects: 1. By constructing an integrated composite sealing structure consisting of thermosetting sealant line bipolar plate sealing, photocuring sealant line anode sealing, and cathode sealing strip cathode sealing, the anode gas sealing groove is equipped with an overflow groove, and the cathode gas sealing groove is equipped with a sealing strip. Each sealing groove circumferentially surrounds the gas-liquid inlet and outlet and the reaction zone, achieving independent sealing of the reaction gas and coolant. This avoids mutual leakage and external leakage of hydrogen, oxygen, and coolant. The overflow groove ensures that the photocuring adhesive is fully and uniformly cured, and the cathode sealing strip maintains assembly maintainability while ensuring sealing effect, thereby improving the sealing reliability, operational stability, and service life of the fuel cell.

[0016] 2. By pre-integrating the bipolar plates into a single structure through thermosetting sealant lines on the coolant side of the anode plate and the coolant side of the cathode plate, the plates are integrated into a whole structure, which improves the overall structural rigidity and torsional resistance of the fuel cell, eliminates the assembly gaps and contact resistance of discrete plates, reduces the sealing breaks in the cooling channels, simplifies the battery assembly process, improves the coaxiality of the plates and membrane electrode assembly, and improves the performance consistency of each cell in the stack.

[0017] 3. By dividing the electrode plate into an outer sealing structure area and a central gas-liquid reaction area, and matching it with a flow guiding structure gas-liquid distribution area, and by adopting a matching design of a parallel wave flow field at the anode and a parallel DC field at the cathode, it can ensure that hydrogen, oxygen and coolant are evenly distributed in the reaction area. The wave coolant flow field and the DC channel coolant flow field work together to enhance the heat transfer of the coolant disturbance, improve the battery heat dissipation efficiency and reaction transmission efficiency, and ensure the power generation performance and operational stability of the fuel cell.

[0018] 4. By setting centrally symmetrical assembly positioning holes on the electrode plate and membrane electrode frame, and using positioning rods to achieve precise alignment, and using a special adhesive tool with limiting blocks and tooling membrane for sealing strip application, high-precision alignment of cathode plate, anode plate, and membrane electrode assembly can be achieved, avoiding assembly offset. The limiting blocks fix the electrode plate to prevent installation displacement, and the tooling membrane enables precise and smooth application of the sealing strip, improving the assembly accuracy and mass production consistency of fuel cells.

[0019] 5. By adopting a step-by-step assembly process of bipolar plate pre-curing, anode vacuum photocuring, cathode sealing strip tooling thermal curing, and integrated fuel cell module unit stacking, the sealing process is cured step by step, ensuring the bonding strength of each sealing structure. The integrated design facilitates batch assembly of the stack and subsequent disassembly and repair of faulty single cells. Vacuum photocuring and positioning stacking further improve sealing quality and assembly efficiency, and reduce production and maintenance costs.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1A three-dimensional structural diagram of a graphite electrode proton exchange membrane fuel cell with integrated adhesive wire sealing provided by the present invention; Figure 2 yes Figure 1 Isometric exploded view; Figure 3 This is a gas-side structural diagram of the anode plate provided by the present invention; Figure 4 This is a structural diagram of the coolant side of the anode plate provided by the present invention; Figure 5 This is a gas-side structural diagram of the cathode plate provided by the present invention; Figure 6 This is a structural diagram of the cooling liquid side of the cathode plate provided by the present invention; Figure 7 This is an isometric exploded view of the membrane electrode assembly provided by the present invention; Figure 8 This is a schematic diagram of the gas-liquid flow direction of a graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing provided by the present invention.

[0022] Figure Labels 1. Coolant inlet; 2. Oxygen outlet; 3. Hydrogen inlet; 4. Coolant outlet; 5. Oxygen inlet; 6. Hydrogen outlet; 7. Thermosetting sealant line; 8. Cathode plate; 9. Cathode sealing strip; 10. Membrane electrode assembly; 11. Photocurable sealant line; 12. Anode plate; 13. Assembly positioning hole; 14. Anode hydrogen distribution area; 15. Anode gas sealing groove; 16. Anode hydrogen flow field; 17. Anode plate outer frame; 18. Anode coolant sealing groove; 19. Anode coolant distribution area; 20. Oxygen guide groove; 21. Anode coolant flow field; 22. Hydrogen guide groove; 23. Cathode plate outer frame; 24. Cathode gas sealing groove; 25. Cathode oxygen distribution area; 26. Cathode oxygen flow field; 27. Cathode coolant sealing groove; 28. Cathode coolant flow field; 29. ​​Cathode-side gas diffusion layer; 30. Frame; 31. Proton exchange membrane; 32. Anode-side gas diffusion layer. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0024] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] Proton exchange membrane fuel cells, as the core clean power generation device for efficient hydrogen energy conversion, have been widely used due to their advantages such as no pollution, high energy conversion efficiency, and convenient hydrogen refueling. However, existing fuel cells generally suffer from uneven stack pressure distribution, high contact resistance, and poor performance and sealing consistency of individual cells. Traditional stacking assembly methods also require the entire stack to be disassembled and repaired when a faulty cell fails, resulting in low maintenance efficiency and high costs. At the same time, gas sealing failure and leakage are prone to occur, making it difficult to balance assembly efficiency, sealing reliability, service life, and the needs of large-scale application.

[0027] Based on the above analysis, this invention is designed. (See appendix.) Figures 1-8 A graphite electrode proton exchange membrane fuel cell with integrated adhesive wire sealing, comprising: The fuel cell body has gas and liquid inlets and outlets at both ends. The fuel cell body includes a cathode plate 8, a membrane electrode assembly 10 and an anode plate 12 stacked in sequence. The cathode plate 8 and the anode plate 12 are respectively arranged on the cathode side and the anode side of the membrane electrode assembly 10. Both the cathode plate 8 and the anode plate 12 include an outer sealing structure area and a central gas-liquid reaction area. The side of the cathode plate 8 and the anode plate 12 facing the membrane electrode assembly 10 is the gas side, and the other side is the coolant side. The coolant side of the anode plate 12 and the coolant side of the adjacent cathode plate 8 are pre-bonded to an integrated bipolar plate by thermosetting sealant line 7. The gas side of the anode plate 12 is sealed to the anode side of the membrane electrode assembly 10 by light-curing sealant line 11, and the gas side of the cathode plate 8 is sealed to the cathode side of the membrane electrode assembly 10 by cathode sealing strip 9.

[0028] Specifically, the cathode plate 8 and anode plate 12 are made of high-density flexible graphite. After molding, the flexible graphite plate is bonded with impregnated resin and then cured at high temperature to form graphite plates with high hardness. The use of high-density flexible graphite plates for cathode plates 8 and anode plates 12, after molding and bonding with impregnated resin and high-temperature curing, improves the structural strength and surface flatness of the plates. Combined with the thermosetting sealing adhesive line 7 of the bipolar plates, this reduces the contact resistance of the plates, improves conductivity, and enhances their resistance to deformation and assembly stability, thereby improving the overall power generation performance and lifespan of the fuel cell. The outer edges of the cathode plate 8 and anode plate 12 are integrally fixed to their outer contours, respectively, enhancing the overall structural strength and assembly rigidity of the plates, providing stable support boundaries, and improving the sealing and structural stability of the bipolar plate bonding and stacking assembly.

[0029] The anode plate 12 has a raised guide groove on each of the two opposite sides of the sealing frame. The two are centrally symmetrical about the geometric center of the sealing frame. One guide groove is located at the junction of the hydrogen inlet 3 and the anode hydrogen distribution area 14, and the other is located between the hydrogen outlet 6 and the anode hydrogen distribution area 14. The raised guide groove serves as a flow channel guiding structure, which can optimize the flow path of hydrogen from the inlet to the distribution area, promote the uniform diffusion of reactants, and the symmetrical layout helps to balance the pressure and fluid distribution in the flow channel and improve the operational stability.

[0030] A specific embodiment of the gas-liquid inlet and outlet in this invention is shown below. Figure 1 As shown, one end of the gas-liquid inlet / outlet includes a coolant inlet 1, an oxygen outlet 2, and a hydrogen inlet 3 arranged at intervals, while the other end includes a coolant outlet 4, an oxygen inlet 5, and a hydrogen outlet 6 arranged at intervals. This design allows for independent flow of hydrogen, oxygen, and coolant without interference, effectively preventing media cross-flow and external leakage risks. It also ensures uniform fluid distribution, low flow resistance, and improves fuel cell reaction efficiency and sealing safety.

[0031] See Figure 8 As shown, hydrogen inlet 3 and hydrogen outlet 6 are centrally symmetrically distributed with the center of the graphite plate as the center of symmetry. Coolant inlet 1 and coolant outlet 4 are also centrally symmetrically distributed. Oxygen inlet 5 and oxygen outlet 2 are located on the left and right sides of the gas-liquid reaction zone along the long side of the graphite plate. The symmetrical arrangement of hydrogen inlet 3 and hydrogen outlet 6, and coolant inlet 1 and coolant outlet 4, with oxygen inlet 5 and oxygen outlet 2 located on the left and right sides of the gas-liquid reaction zone along the long side of the graphite plate, allows for a more balanced distribution of flow pressure and velocity in the hydrogen, oxygen, and coolant channels within the electrode plate. This reduces fluid resistance and local dead zones, improves the uniformity of gas-liquid distribution and reaction stability, and also facilitates mold processing and assembly positioning.

[0032] A specific embodiment of the membrane electrode assembly 10 in this invention is shown below. Figure 7 As shown, the membrane electrode assembly 10 includes a proton exchange membrane 31 coated with a catalyst, a cathode-side gas diffusion layer 29, an anode-side gas diffusion layer 32, and a frame 30. The frame 30 is a PET frame, and the proton exchange membrane 31 is disposed inside the frame 30. The cathode-side gas diffusion layer 29 and the anode-side gas diffusion layer 32 are respectively disposed on the cathode side and anode side of the proton exchange membrane 31, and both the cathode-side gas diffusion layer 29 and the anode-side gas diffusion layer 32 are located in the gas-liquid reaction zone. The membrane electrode assembly 10 uses a PET frame 30 to wrap and position the proton exchange membrane 31, and the cathode-side gas diffusion layer 29 and the anode-side gas diffusion layer 32 are correspondingly arranged on both sides of the proton exchange membrane 31 and confined within the gas-liquid reaction zone. This not only provides structural support and a sealing assembly reference for the membrane electrode assembly 10 through the frame 30, but also ensures that the cathode-side gas diffusion layer 29 and the anode-side gas diffusion layer 32 are precisely matched with the gas-liquid reaction zone of the electrode plate, ensuring efficient transmission and full reaction of the reaction gas, while preventing sealant from intruding into the reaction zone, thus improving the reaction efficiency and sealing stability of the fuel cell.

[0033] Specifically, the frame 30 is used to fix the membrane electrode assembly. Both ends of the frame 30 have three inlets and outlets spaced apart along the short side of the membrane electrode assembly. The length and width of the frame 30 are slightly larger than the length and width of the electrode plate to improve sealing reliability. The area of ​​the cathode-side gas diffusion layer 29 and the anode-side gas diffusion layer 32 is larger than the area of ​​the active area to prevent uneven distribution of clamping force due to inconsistent height during stack assembly, which could cause electrode plate compression deformation and affect the power generation performance and stability of the fuel cell.

[0034] In a specific embodiment of the anode plate 12 of the present invention, the gas side of the anode plate 12 is provided with a plurality of anode gas sealing grooves 15 with overflow grooves. The plurality of anode gas sealing grooves 15 are arranged circumferentially around the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone. The light-curing sealing glue line 11 is a UV light-curing glue line, and the anode gas sealing groove 15 is sealed and bonded to the frame 30 through the UV light-curing glue line. During curing, excess glue overflows into the overflow groove to achieve anode sealing. Correspondingly, the gas-liquid reaction zone is provided with an anode hydrogen distribution area 14 with a flow guiding structure and a parallel wave-shaped anode hydrogen flow field 16. Both ends of the anode hydrogen flow field 16 are connected to the hydrogen inlet 3 and the hydrogen outlet 6 through the anode hydrogen distribution area 14, respectively. The anode hydrogen distribution area 14 and the anode hydrogen flow field 16 are correspondingly matched with the anode-side gas diffusion layer 32 to achieve uniform distribution and reaction transmission of hydrogen. An anode gas sealing groove 15 with an overflow groove is provided on the gas side of the anode plate 12, which surrounds the gas-liquid inlet and outlet and the outer side of the gas-liquid reaction zone. It is sealed and bonded to the frame 30 by UV curing adhesive lines. Excess adhesive can be discharged into the overflow groove to ensure that the sealing layer is full and uniform, without bubbles or missing adhesive, thus improving the reliability of the anode seal. The anode hydrogen distribution zone 14 with a flow guiding structure in the gas-liquid reaction zone is connected to the hydrogen inlet 3 and hydrogen outlet 6 by the parallel wave-shaped anode hydrogen flow field 16, and is precisely matched with the anode-side gas diffusion layer 32 to achieve uniform distribution and smooth transmission of hydrogen, eliminate flow dead zones and local accumulation, and significantly improve the anode reaction efficiency and battery operation stability.

[0035] In the above embodiment, the anode plate 12 has multiple anode coolant sealing grooves 18 on the coolant side. These grooves 18 are arranged circumferentially around the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone. Correspondingly, the gas-liquid reaction zone has an anode coolant distribution area 19 with a flow-guiding structure and a parallel wavy anode coolant flow field 21. Both ends of the anode coolant flow field 21 are connected to the coolant inlet 1 and coolant outlet 4 through the anode coolant distribution area 19, respectively. The anode coolant sealing grooves 18 on the coolant side of the anode plate 12 circumferentially surround the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone, forming a comprehensive closed-loop seal. This effectively prevents coolant leakage and cross-contamination with the reacting gas, ensuring the safe operation of the fluid system. The anode coolant distribution area 19 with a flow-guiding structure and the parallel wavy anode coolant flow field 21 connect the coolant inlet 1 and coolant outlet 4, allowing the coolant to flow evenly into the entire gas-liquid reaction zone, avoiding localized overheating. Furthermore, the wavy flow field increases the heat exchange area, enhances fluid turbulence, improves cooling and heat exchange efficiency, maintains stable fuel cell operating temperature, and extends service life.

[0036] In a specific embodiment of the cathode plate 8 in this invention, the cathode plate 8 has a cathode gas sealing groove 24 on the gas side. The cathode gas sealing groove 24 is arranged circumferentially around the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone. The cathode gas sealing groove 24 is sealed by the cathode sealing strip 9 and the frame 30 to achieve cathode sealing. The cathode sealing strip 9 is a silicone sealing strip. Correspondingly, the gas-liquid reaction zone has a cathode oxygen distribution area 25 with a flow guiding structure and a parallel DC channel cathode oxygen flow field 26. Both ends of the cathode oxygen flow field 26 are connected to the oxygen inlet 5 and the oxygen outlet 2 through the cathode oxygen distribution area 25, respectively. The cathode oxygen distribution area 25 and the cathode oxygen flow field 26 are correspondingly matched with the cathode-side gas diffusion layer 29 to achieve uniform distribution and reaction transmission of oxygen. The cathode gas sealing groove 24 on the gas side of the cathode plate 8 surrounds the gas-liquid inlet and outlet and the outer side of the gas-liquid reaction zone. It is sealed with the silicone cathode sealing strip 9 and the frame 30 to form a stable and reliable cathode sealing barrier, which prevents oxygen leakage and cross-contamination of gas and liquid media. The cathode oxygen distribution area 25 with a flow guiding structure is connected to the oxygen inlet 5 and oxygen outlet 2 through the parallel DC cathode oxygen flow field 26. It is precisely matched with the cathode-side gas diffusion layer 29, which can realize the uniform distribution and smooth transmission of oxygen in the gas-liquid reaction zone, eliminate flow dead zones, and ensure the continuous and stable progress of the cathode electrochemical reaction. At the same time, the flexible contact method of the cathode sealing strip can also improve the assembly adaptability and long-term sealing reliability.

[0037] In the above embodiments, a hydrogen guide channel 22 is provided between the hydrogen inlet 3 and the anode hydrogen distribution area 14, and an oxygen guide channel 20 is provided between the oxygen inlet 5 and the cathode oxygen distribution area 25. The hydrogen guide channel 22 is used to buffer and uniformly guide the gas input from the hydrogen inlet 3 into the anode hydrogen distribution area 14, and the oxygen guide channel 20 is used to buffer and stabilize the gas input from the oxygen inlet 5 and uniformly send it into the cathode oxygen distribution area 25. This can avoid the problem of local erosion of the flow field and uneven flow distribution caused by direct injection of high-pressure gas, so that hydrogen and oxygen can enter the corresponding flow field more smoothly, further improving the uniformity of gas distribution and the stability of electrochemical reaction.

[0038] In the above embodiment, the cathode sealing strip 9 is bonded to the cathode plate 8 by means of a bonding fixture. The bonding fixture includes a fixture body, a limiting block, and a fixture film. There are multiple limiting blocks arranged circumferentially around the cathode plate 8 to limit and fix it. The cathode sealing strip 9 is embedded in the fixture film. The surface of the cathode sealing strip 9 is sprayed with sealing glue lines and can be attached and smoothed into the cathode gas sealing groove 24. After removing the fixture film, the cathode plate 8 is placed in a constant temperature box for heat curing to achieve fixed bonding between the cathode sealing strip 9 and the cathode gas sealing groove 24. The bonding fixture reliably limits and fixes the cathode plate 8 through circumferentially arranged limiting blocks, which can prevent the electrode plate from shifting or misaligning during the bonding process of the cathode sealing strip 9. The fixture membrane accurately positions the cathode sealing strip 9 and evenly applies and smooths the thermosetting sealing adhesive line 7 into the cathode gas sealing groove 24, ensuring that the sealing strip is bonded flat without warping. Subsequent heat curing in a constant temperature chamber can firmly bond the cathode sealing strip 9 to the cathode gas sealing groove 24, which not only improves the accuracy of the cathode sealing position and the consistency of sealing, but also simplifies the assembly process, improves the efficiency of mass production, and ensures the long-term sealing reliability of the cathode.

[0039] In the above embodiment, the cathode plate 8 is provided with a cathode coolant sealing groove 27 on the coolant side. The cathode coolant sealing groove 27 is arranged circumferentially around the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone and is sealed to the anode coolant sealing groove 18 through thermosetting sealant line 7 to achieve coolant sealing. The thermosetting sealant line 7 is an epoxy line. A parallel direct-flow cathode coolant flow field 28 is provided in the gas-liquid reaction zone. The two ends of the cathode coolant flow field 28 are connected to the coolant inlet 1 and the coolant outlet 4, respectively. The cathode coolant flow field 28 and the anode coolant flow field 21 are distributed accordingly to enhance the heat transfer of coolant disturbance. The cathode coolant sealing groove 27 on the coolant side of the cathode plate 8 surrounds the gas-liquid inlet and outlet and the outside of the gas-liquid reaction zone. It is sealed to the anode coolant sealing groove 18 of the anode plate 12 through thermosetting sealant line 7, forming a fully enclosed closed-loop coolant sealing structure, which can prevent coolant leakage and cross-contamination with the reaction gas. The parallel direct-flow cathode coolant flow field 28 connects the coolant inlet 1 and the coolant outlet 4 and is distributed correspondingly to the anode coolant flow field 21. It can form strong fluid turbulence in the cooling channel, increase the heat exchange area and improve the heat exchange efficiency. At the same time, the direct-flow structure can reduce the coolant flow resistance, ensure smooth cooling circulation and stably maintain the operating temperature of the fuel cell.

[0040] In other embodiments of the present invention, assembly positioning holes 13 are correspondingly provided on the sealing structure areas of the cathode plate 8 and the anode plate 12, as well as on the frame 30. These assembly positioning holes 13 are symmetrically arranged along the center of the electrode frame and, during assembly, cooperate with positioning rods to achieve precise alignment of the cathode plate 8, anode plate 12, and frame 30. The centrally symmetrically arranged assembly positioning holes 13 on the cathode plate 8, anode plate 12, and frame 30, combined with the positioning rods, ensure precise alignment during assembly, preventing misalignment of components and ensuring accurate alignment of the sealing structure with the flow field area. This improves overall sealing reliability and gas-liquid transmission uniformity, enhances assembly efficiency and stack structure consistency, and guarantees long-term stable operation of the fuel cell.

[0041] The assembly method for graphite-based proton exchange membrane fuel cells is as follows: The coolant sides of the anode and cathode plates are thermo-cured with epoxy adhesive to form bipolar plates. The gas side of the anode plate and the membrane electrode assembly are bonded together with a cathode sealing strip via UV-cured adhesive and the gas side of the cathode plate to form an integrated fuel cell assembly. Multiple fuel cell assemblies are stacked sequentially and sealed together using positioning rods. The cathode plate of each individual fuel cell assembly is sealed to the frame of an adjacent individual fuel cell assembly via a cathode sealing strip to form the main body of the fuel cell.

[0042] In summary, by employing an integrated sealed fuel cell structure, multi-region closed-loop sealing, symmetrical media inlet and outlet layout, precise positioning assembly, and coupled cooling flow field design, problems such as fuel cell seal failure, media cross-contamination, uneven gas-liquid distribution, local overheating, assembly misalignment, and insufficient sealing strip bonding precision have been solved. This has enabled independent flow, uniform transmission, and efficient heat exchange of hydrogen, oxygen, and coolant, improving sealing reliability, assembly precision, and structural stability, ensuring the continuous and stable conduct of electrochemical reactions, while also optimizing the assembly process and extending the overall service life of the fuel cell.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing, characterized in that, include: The fuel cell body has gas and liquid inlets and outlets at both ends. The fuel cell body includes a cathode plate (8), a membrane electrode assembly (10), and an anode plate (12) stacked in sequence. The cathode plate (8) and the anode plate (12) are respectively arranged on the cathode side and anode side of the membrane electrode assembly (10). The cathode plate (8) and the anode plate (12) both include a sealing structure area on the periphery and a gas-liquid reaction area in the center. The side of the cathode plate (8) and the anode plate (12) facing the membrane electrode assembly (10) are both gas sides and the other side is a coolant side. The coolant side of the anode plate (12) and the coolant side of the adjacent cathode plate (8) are pre-bonded as an integrated bipolar plate by thermosetting sealant line (7). The gas side of the anode plate (12) is sealed to the anode side of the membrane electrode assembly (10) by light-curing sealant line (11). The gas side of the cathode plate (8) is sealed to the cathode side of the membrane electrode assembly (10) by cathode sealing strip (9).

2. The graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 1, characterized in that: One end of the gas-liquid inlet and outlet includes a coolant inlet (1), an oxygen outlet (2), and a hydrogen inlet (3) arranged at intervals, and the other end of the gas-liquid inlet and outlet includes a coolant outlet (4), an oxygen inlet (5), and a hydrogen outlet (6) arranged at intervals.

3. The graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 2, characterized in that: The membrane electrode assembly (10) includes a proton exchange membrane (31) coated with a catalyst, a cathode-side gas diffusion layer (29), an anode-side gas diffusion layer (32), and a frame (30). The proton exchange membrane (31) is arranged inside the frame (30). The cathode-side gas diffusion layer (29) and the anode-side gas diffusion layer (32) are respectively arranged on the cathode side and the anode side of the proton exchange membrane (31), and both the cathode-side gas diffusion layer (29) and the anode-side gas diffusion layer (32) are located in the gas-liquid reaction zone.

4. The graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 3, characterized in that: The anode plate (12) has multiple anode gas sealing grooves (15) with overflow grooves on the gas side. The multiple anode gas sealing grooves (15) are arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. The anode gas sealing grooves (15) are sealed and bonded to the frame (30) through the light-curing sealant line (11). When curing, excess adhesive overflows into the overflow groove to achieve anode sealing. The gas-liquid reaction zone is provided with an anode hydrogen distribution area (14) with a flow guiding structure and a parallel wave-shaped anode hydrogen flow field (16). Both ends of the anode hydrogen flow field (16) are connected to the hydrogen inlet (3) and the hydrogen outlet (6) through the anode hydrogen distribution area (14). The anode hydrogen distribution area (14) and the anode hydrogen flow field (16) are correspondingly matched with the anode-side gas diffusion layer (32) to achieve uniform distribution and reaction transmission of hydrogen.

5. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 4, characterized in that: The anode plate (12) has multiple anode coolant sealing grooves (18) on the coolant side. The multiple anode coolant sealing grooves (18) are arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. The gas-liquid reaction zone is provided with an anode coolant distribution area (19) with a flow guiding structure and a parallel wave-shaped anode coolant flow field (21). Both ends of the anode coolant flow field (21) are connected to the coolant inlet (1) and the coolant outlet (4) through the anode coolant distribution area (19).

6. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 5, characterized in that: The cathode plate (8) has a cathode gas sealing groove (24) on the gas side. The cathode gas sealing groove (24) is arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone. The cathode gas sealing groove (24) is sealed by the cathode sealing strip (9) and the frame (30) to achieve cathode sealing. The gas-liquid reaction zone is provided with a cathode oxygen distribution area (25) with a flow guiding structure and a parallel DC channel cathode oxygen flow field (26). Both ends of the cathode oxygen flow field (26) are connected to the oxygen inlet (5) and the oxygen outlet (2) through the cathode oxygen distribution area (25). The cathode oxygen distribution area (25) and the cathode oxygen flow field (26) are respectively matched with the cathode side gas diffusion layer (29) to achieve uniform distribution and reaction transmission of oxygen.

7. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 6, characterized in that: The cathode sealing strip (9) is bonded to the cathode graphite plate by means of a bonding fixture. The bonding fixture includes a fixture body, a limiting block and a fixture film. The limiting block is multiple and arranged circumferentially around the cathode plate (8) to limit and fix it. The cathode sealing strip (9) is embedded in the fixture film. The surface of the cathode sealing strip (9) is sprayed with sealing glue line and can be attached and smoothed in the cathode gas sealing groove (24). After removing the fixture film, the cathode plate (8) is placed in a constant temperature box for heat curing to achieve the fixed bonding of the cathode sealing strip (9) and the cathode gas sealing groove (24).

8. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 7, characterized in that: The cathode plate (8) has a cathode coolant sealing groove (27) on the coolant side. The cathode coolant sealing groove (27) is arranged circumferentially around the gas-liquid inlet and outlet and the gas-liquid reaction zone and is sealed to the anode coolant sealing groove (18) through the thermosetting sealant line (7) to achieve coolant sealing. A parallel direct-flow cathode coolant flow field (28) is provided in the gas-liquid reaction zone. The two ends of the parallel direct-flow cathode coolant flow field (28) are connected to the coolant inlet (1) and the coolant outlet (4) respectively. The cathode coolant flow field (28) and the anode coolant flow field (21) are distributed accordingly to enhance the heat transfer of coolant disturbance.

9. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 8, characterized in that: Assembly positioning holes (13) are provided on the sealing structure area of ​​the cathode plate (8) and the anode plate (12) as well as on the frame (30). The assembly positioning holes (13) are symmetrically arranged along the center of the frame (30) and are positioned in conjunction with the positioning rod during assembly to achieve precise alignment of the cathode plate (8), the anode plate (12) and the frame (30).

10. A graphite electrode proton exchange membrane fuel cell with integrated adhesive sealing according to claim 9, characterized in that: The specific assembly method of the proton exchange membrane fuel cell based on the graphite plates is as follows: The coolant sides of the anode and cathode plates are thermosetting to form an integrated bipolar plate via thermosetting sealant. The gas side of the anode plate and the membrane electrode assembly are bonded to the cathode plate via photocuring sealant and a cathode sealing strip to form an integrated fuel cell assembly. Then, with the aid of positioning rods, multiple fuel cell assemblies are stacked sequentially and sealed together. The cathode plate of a single fuel cell assembly is sealed to the frame of the adjacent single fuel cell assembly via a cathode sealing strip to form the main body of the fuel cell.

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