Fuel cell monomer and fuel cell stack

Abstract

The utility model provides a fuel cell monomer and a fuel cell stack. The fuel cell monomer comprises a cathode plate, a membrane electrode and an anode plate which are sequentially stacked; the membrane electrode comprises a proton exchange membrane and a membrane electrode frame; the membrane electrode frame comprises a cathode side frame and an anode side frame, the cathode side frame and the anode side frame are attached to each other to form an accommodating cavity, and the proton exchange membrane is embedded in the accommodating cavity; the cathode and anode side frames are respectively provided with a first hollow part and a second hollow part; and cathode carbon paper and anode carbon paper are respectively arranged on the surfaces of the proton exchange membranes positioned in the first hollow part and the second hollow part. The single fuel cell is of an integrated single cell structure with high reliability, realizes tight combination of the polar plate and the membrane electrode, can effectively improve the assembly precision, efficiency and sealing performance, and can reduce the requirement on pressure during assembly at the same time; and moreover, the fuel cell monomer can effectively prevent the carbon paper from being embedded into a polar plate flow channel due to over-voltage of the membrane electrode, and even mechanical damage in a severe case.

Description

Technical Field

[0001] The utility model relates to a fuel cell monomer and a fuel cell stack. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) are widely used in transportation due to their high energy density, high efficiency, and pollution-free operation. Currently, fuel cell stacks are becoming increasingly powerful to meet the demands of heavy-duty applications. In addition to improving battery performance, the primary approaches to increasing power are increasing the active area and the number of fuel cells in the stack. However, this increase in active area presents challenges in achieving uniform distribution within the stack, and the increased number of cells also poses a significant challenge to stack assembly.

[0003] In traditional designs, the alignment and sealing between the membrane electrode and the electrode plate rely on separate clamping forces and sealing rings. This approach is prone to problems such as alignment deviation between the membrane electrode and the electrode plate, poor sealing, and uneven assembly pressure in high-power, multi-cell stacks, which in turn leads to reduced stack performance and shortened service life. Utility Model Content

[0004] To overcome the shortcomings of existing fuel cell monomers, such as insufficient sealing performance and the difficulty in achieving high assembly precision and efficiency, the present invention proposes a fuel cell monomer and a fuel cell stack. The fuel cell monomer of the present invention is a highly reliable, integrated single-cell structure. Using a sealant film bonding technique, it achieves a tight bond between the electrode plate and the membrane electrode, effectively improving assembly precision and efficiency, as well as sealing performance, while reducing assembly pressure requirements. Furthermore, the fuel cell monomer effectively prevents overpressure on the membrane electrode, which can cause carbon paper to become embedded in the electrode plate flow channels, and in severe cases, even cause mechanical damage.

[0005] The utility model solves the above technical problems through the following technical solutions:

[0006] The utility model provides a fuel cell monomer, which comprises a cathode plate, a membrane electrode and an anode plate stacked in sequence;

[0007] The membrane electrode comprises a proton exchange membrane and a membrane electrode frame; the membrane electrode frame comprises an anode side frame and a cathode side frame, the anode side frame and the cathode side frame being bonded to each other to form a receiving cavity, and the proton exchange membrane is embedded in the receiving cavity; the cathode side frame and the anode side frame are respectively provided with a first hollow portion and a second hollow portion; cathode carbon paper is provided on the surface of the proton exchange membrane located in the first hollow portion, and anode carbon paper is provided on the surface of the proton exchange membrane located in the second hollow portion;

[0008] The cathode plate includes a cathode reaction area, a cathode mixing area and a cathode sealing structure area, wherein the cathode mixing area is arranged at the outer edge of the cathode reaction area, and the cathode sealing structure area is arranged around the periphery of the cathode mixing area; the thickness of the cathode sealing structure area is smaller than that of the cathode mixing area; a first sealing film is provided between the cathode sealing structure area and the cathode side frame;

[0009] The anode plate includes an anode reaction area, an anode mixed flow area and an anode sealing structure area. The anode mixed flow area is arranged at the outer edge of the anode reaction area, and the anode sealing structure area is arranged around the periphery of the anode mixed flow area; the thickness of the anode sealing structure area is less than the thickness of the anode mixed flow area; a second sealing film is provided between the anode sealing structure area and the anode side frame.

[0010] In the present invention, the cathode plate and the anode plate are bonded to the membrane electrode via a first sealing film and a second sealing film respectively, which not only ensures the sealing of the fuel cell monomer but also enables the fuel cell to be combined into an integrated single cell.

[0011] In the present invention, the first sealing film and the second sealing film have a certain elasticity to provide space for thermal expansion and contraction of the fuel cell monomer during operation.

[0012] In the present invention, the area of ​​the proton exchange membrane is generally larger than the area of ​​the cathode reaction zone or the anode reaction zone.

[0013] In the present invention, the thickness of the proton exchange membrane can be 10 μm, which does not affect its coordination with the anode plate and the cathode plate.

[0014] In the present invention, the anode mixed flow region and the cathode mixed flow region may be a multi-layer composite structure.

[0015] In some embodiments, the first sealant film and the second sealant film are made of polyolefin.

[0016] In some embodiments, the cathode sealing structure area is at the same height as the cathode reaction area, and the height is adjusted by a first sealing film.

[0017] In some embodiments, the thickness of the first sealing film is 25-75 μm; within this thickness range, the elastic space of the first sealing film is relatively small, which can avoid overpressure of the membrane electrode and ensure the stability of the fuel cell monomer during the preparation process.

[0018] In some embodiments, the anode sealing structure area is at the same height as the anode reaction area, and the height is adjusted by a second sealing film.

[0019] In some embodiments, the thickness of the second sealing film is 25-75 μm; within this thickness range, the elastic space of the second sealing film is relatively small, which can avoid overpressure of the membrane electrode and ensure the stability of the fuel cell monomer during the preparation process.

[0020] In the present invention, by designing the thickness of the sealing film, good contact between the membrane electrode and the anode and cathode plates is ensured while ensuring sealing, and the proton exchange membrane is kept in a horizontal plane to avoid mechanical damage at the turning point.

[0021] The first sealing film and the second sealing film can resist corrosion from chemical substances such as electrolytes and fuels, and maintain stable physical and chemical properties within the operating temperature range.

[0022] In some embodiments, the thickness of the cathode carbon paper satisfies: D1=d1+h1≥d1+d2; wherein the thickness of the cathode carbon paper is D1, d1 is the thickness of the cathode side frame, d2 is the thickness of the first sealing film, and h1 is the thickness difference between the cathode mixing area and the cathode reaction area.

[0023] The thickness D1 of the cathode carbon paper may be the thickness of the cathode carbon paper after compression.

[0024] In some embodiments, the thickness of the anode carbon paper satisfies: D2=d3+h2≤d3+d4; wherein the thickness of the anode carbon paper is D2, d3 is the thickness of the anode side frame, d4 is the thickness of the second sealing film, and h2 is the thickness difference between the anode mixed flow area and the anode reaction area.

[0025] The thickness D2 of the anode carbon paper may be the thickness of the anode carbon paper after compression.

[0026] In the present invention, the thickness of the membrane electrode is designed to match the sealing structure area, mixed flow area, and reaction area of ​​the anode and cathode plates, ensuring that the height of the membrane electrode matches that of the anode and cathode plates after hot pressing. The cathode carbon paper is compressed to D1 of 180 μm, d1 of 130 μm, h1 of 50 μm, and d2 of 50 μm, meeting the cathode side requirement: D1 = d1 + h1 ≥ d1 + d2. The anode carbon paper is compressed to D2 of 180 μm, d3 of 180 μm, d4 of 50 μm, and h2 of 0, meeting the anode side requirement: D2 = d3 + h2 ≤ d3 + d4. Conventional designs in the field are such that the height of the single-sided carbon paper is equal to the sum of the compressed heights of the single-sided frame and the single-sided sealing line. This results in an unstable overall height after compression, leading to inconsistent battery performance.

[0027] In some embodiments, the width of the first sealing film and the width of the second sealing film are both 3-8 mm; the directions of the width of the first sealing film and the width of the second sealing film are consistent with the length direction of the proton exchange membrane; the width design of the first sealing film and the second sealing film can prevent gas leakage during operation of the fuel cell monomer and ensure the safety of the battery monomer.

[0028] In some embodiments, the cross-sectional shape of the cathode side frame is the same as the cross-sectional shape of the cathode sealing structure area.

[0029] In some embodiments, the cross-sectional shape of the anode side frame is the same as the cross-sectional shape of the anode sealing structure area.

[0030] In a specific embodiment, the cross-sectional shape of the first sealing adhesive film is the same as the cross-sectional shape of the cathode sealing structure area.

[0031] In a specific embodiment, the cross-sectional shape of the second sealing adhesive film is the same as the cross-sectional shape of the anode sealing structure area.

[0032] In some embodiments, one end of the membrane electrode frame, one end of the cathode plate, and one end of the anode plate are each provided with a hydrogen inlet, a coolant inlet, and an air inlet.

[0033] In a specific embodiment, the fuel cell unit further includes a sealing rubber line, which is provided at the outer edge of the fuel cell unit and functions to seal the coolant field; the sealing rubber line forms a sealing ring at the outer edge of the fuel cell unit.

[0034] In the present invention, the fuel cell monomer can be sealed by directly injecting a sealing glue line or bonding a prefabricated sealing glue line.

[0035] When using sealant lines for sealing, they are designed to have a certain degree of elasticity, allowing them to fill gaps between parts when compressed, creating a tight contact. In a fuel cell stack, when the fuel cell cells are clamped together, the sealant lines are squeezed and elastically deformed, filling any tiny gaps that may exist and preventing coolant or reactant gas leakage.

[0036] The sealing structure area, mixed flow area and reaction area of ​​the cathode plate and the anode plate take into account the sealing and thickness matching of the membrane electrode, and the close combination of the cathode plate, the anode plate and the membrane electrode is achieved through the sealing film bonding technology.

[0037] In some embodiments, the cathode plate and the anode plate are made of metal, graphite, or a composite material of metal and graphite.

[0038] Among them, the molding process of the cathode plate and the anode plate is conventional in this field. Based on the different materials of the anode and cathode plates, the selection of sealing materials and processes are also different; specifically, including but not limited to molding, stamping, machining and etching processes.

[0039] In the present invention, the fuel cell monomers are stacked in sequence to form a cooling liquid field, which is elastically compressed and sealed by a sealing rubber line. The molding method can be pasting the prefabricated rubber line and in-situ direct injection molding on the plate.

[0040] In the present invention, the design positions of the cathode plate and the anode plate are conventional in this field. The membrane electrode is placed on the upper surface of the anode plate, and the anode catalyst layer side of the membrane electrode is downwardly corresponding to the anode plate; the upper surface of the anode plate is provided with a gas flow channel, and the sealing structure area is used for bonding the sealing film; then the cathode plate is placed in sequence on the cathode catalyst layer side of the membrane electrode; the lower surface of the cathode plate contacts the cathode side of the membrane electrode, and the lower surface of the cathode plate is provided with a gas flow channel, and the sealing structure area is used for bonding the sealing film.

[0041] In the present invention, the anode plate, membrane electrode, and cathode plate can be cold-pressed by setting pressure and time to obtain a preliminary battery cell. This preliminary battery cell can then be hot-pressed according to the hot-pressing temperature, pressure, and time to obtain an integrated fuel cell cell. The pressure and temperature mentioned above may vary depending on the film curing conditions of different manufacturers or different materials.

[0042] In the present invention, those skilled in the art should know that “battery cell” and “single battery” have the same meaning.

[0043] In the present invention, the general steps for preparing the fuel cell monomer are as follows: during the membrane electrode manufacturing process, the first and second sealing films are simultaneously adhered to the frame. The centrifugal film of the second sealing film on the anode side is peeled off and placed on the anode plate through the positioning hole; the centrifugal film of the first sealing film on the cathode side is peeled off and the cathode plate is placed on it. The anode plate, membrane electrode, and cathode plate are aligned with each other through the positioning holes and cold-pressed using a tool according to the set pressure and time to obtain a preliminary fuel cell monomer. The preliminary fuel cell monomer is then hot-pressed according to the set hot-pressing temperature, pressure, and time to obtain an integrated fuel cell monomer. Using cold-pressing and hot-pressing processes, appropriate pressure, time, and temperature parameters are set according to the material properties to complete the production of the single cell. The designed single cell production method facilitates repeated production and industrialized production. At the same time, the adhesive seal between the electrode plate and the membrane electrode 11 can maintain the consistency of the single cell in mass production.

[0044] The utility model provides a fuel cell stack, which includes a first current collecting plate, a first insulating top plate, a first end plate, a second current collecting plate, a second insulating top plate, a second end plate, and the fuel cell monomer as described above; the first current collecting plate, the first insulating top plate, and the first end plate are sequentially provided from the cathode plate of the fuel cell monomer toward the outside; and the second current collecting plate, the second insulating top plate, and the second end plate are sequentially provided from the anode plate of the fuel cell monomer toward the outside.

[0045] In the present invention, the number of fuel cell monomers can be determined according to the power required by the fuel cell stack; the number of fuel cell monomers is n, where n is a positive integer greater than 1.

[0046] In the present invention, the fuel cell monomers can be arranged in a conventional manner in the art to form a fuel cell stack; wherein a coolant circulation space is formed between the fuel cell monomers.

[0047] The positive progress effect of this utility model is:

[0048] (1) In the fuel cell monomer of the present application, the cathode and anode plates are bonded to the membrane electrode by a sealing film, and the elastic compression space is small, which can effectively prevent the overpressure of the membrane electrode from causing the carbon paper to be embedded in the flow channel of the anode and cathode plates; and the structural strength of the fuel cell monomer is high, especially for ultra-thin plates, which can greatly improve the structural strength and facilitate assembly; it can effectively improve the assembly accuracy, production efficiency and sealing performance, and at the same time reduce the requirements for the assembly pressure of the stack.

[0049] (2) Due to the high positioning accuracy between the anode and cathode plates and the membrane electrode in the fuel cell of the present application, it is not affected by the number of sections in the fuel cell stack assembly, and effectively avoids the misalignment of the plates on both sides of the membrane electrode when assembling a multi-section stack;

[0050] (3) Due to the structural design of the fuel cell monomer of the present application, the subsequent fuel cell monomer manufacturing process can be simplified, and the production efficiency and the consistency of the single cell can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a front view of a fuel cell unit according to Example 1 of the present utility model;

[0052] Figure 2 This is a schematic diagram of the exploded structure of a fuel cell unit according to Example 1 of the present utility model;

[0053] Figure 3 This is a schematic diagram of the partial structure of the cathode plate or anode plate in the fuel cell unit of Example 1 of the present utility model;

[0054] Figure 4This is a schematic structural diagram of a partial longitudinal cross section of a fuel cell unit according to Example 1 of the present utility model;

[0055] Figure 5 This is a highly schematic diagram of a portion of the structure of a fuel cell unit according to Example 1 of the present utility model;

[0056] Figure 6 This is a schematic structural diagram of the cooling field sealing rubber line in the fuel cell unit of Example 1 of the present utility model;

[0057] Figure 7 This is a cross-sectional schematic diagram of a cooling field sealing rubber line in a fuel cell unit according to Example 1 of the present utility model;

[0058] Figure 8 This is a schematic structural diagram of a hot pressing tool for an anode plate in a fuel cell unit according to Example 1 of the present utility model;

[0059] Figure 9 This is a schematic structural diagram of the fuel cell stack of Example 2 of the present utility model.

[0060] Description of reference numerals:

[0061] First end plate 1

[0062] First insulating top plate 2

[0063] First collecting plate 3

[0064] Fuel cell 4

[0065] Sealant line 5

[0066] Second collecting plate 6

[0067] Second insulating top plate 7

[0068] Second end plate 8

[0069] Cathode plate 9

[0070] First sealing film 10

[0071] Membrane Electrode 11

[0072] Second sealing film 12

[0073] Anode plate 13

[0074] Reaction zone 14

[0075] Mixed flow area 15

[0076] Sealing structure area 16

[0077] Positioning hole 17

[0078] Anode carbon paper 18

[0079] Cathode carbon paper 19

[0080] Cathode side frame 20

[0081] Proton exchange membrane 21

[0082] Anode side frame 22

[0083] Anode plate tooling 23

[0084] Hot pressing surface 24. DETAILED DESCRIPTION

[0085] Preferred embodiments are listed below and combined with the accompanying drawings to more clearly and completely illustrate the present invention.

[0086] Example 1

[0087] This embodiment discloses a fuel cell monomer. Figure 1 A front view of a fuel cell unit of this embodiment;

[0088] The integrated fuel cell unit 4 includes a cathode plate 9, a membrane electrode 11, and an anode plate 13 stacked in sequence; the membrane electrode 11 includes a proton exchange membrane 21 and a membrane electrode 11 frame; the membrane electrode 11 frame includes an anode side frame 22 and a cathode side frame 20, the anode side frame 22 and the cathode side frame 20 being bonded to each other to form a receiving cavity, and the proton exchange membrane 21 is embedded in the receiving cavity; the cathode side frame 20 and the anode side frame 22 are respectively provided with a first hollow portion and a second hollow portion; a cathode carbon paper 19 is provided on the surface of the proton exchange membrane 21 located in the first hollow portion, and an anode carbon paper 18 is provided on the surface of the proton exchange membrane 21 located in the second hollow portion;

[0089] The cathode plate 9 includes a cathode reaction area 14, a cathode mixing area 15, and a cathode sealing structure area 16. The cathode mixing area 15 is located at the outer edge of the cathode reaction area 14, and the cathode sealing structure area 16 is arranged around the periphery of the cathode mixing area 15. The thickness of the cathode sealing structure area 16 is less than that of the cathode mixing area 15. A first sealing film 10 is provided between the cathode sealing structure area 16 and the cathode side frame 20.

[0090] The anode plate 13 includes an anode reaction area 14, an anode mixed flow area 15 and an anode sealing structure area 16. The anode mixed flow area 15 is arranged at the outer edge of the anode reaction area 14, and the anode sealing structure area 16 is arranged around the periphery of the anode mixed flow area 15; the thickness of the anode sealing structure area 16 is less than the thickness of the anode mixed flow area 15; a second sealing film 12 is provided between the anode sealing structure area 16 and the anode side frame 22.

[0091] Figure 2 is a schematic diagram of the exploded structure of the fuel cell unit of this embodiment, as shown in FIG. Figure 2As shown, the first sealing film 10 is the cathode sealing film, the second sealing film 12 is the anode sealing film, and the above-mentioned cathode plate 9, anode plate 13 and membrane electrode 11 (MEA) are bonded into one body by the sealing films on both sides. The membrane electrode 11 is located between the cathode and anode plates, and each component is assembled and positioned through the positioning holes 17.

[0092] Figure 3 This is a partial structural diagram of the cathode plate or anode plate in the fuel cell unit of Example 1 of the present utility model, as shown in FIG. Figure 3 As shown, the cathode plate 9 includes a reaction zone 14, a mixed flow structure zone 15, a sealing structure zone 16, and a positioning hole 17; the reaction zone 14 is composed of a wavy or straight-line arranged flow channel, and is the area where the gas and the catalyst undergo electrochemical reaction; the mixed flow zone 15 is located at the inlet and outlet areas of the cathode plate 9, and is mainly responsible for the distribution and mixing of gas and water, and the material enters and exits the mixed flow zone 15 through the pore channel on the membrane electrode 11; the sealing structure zone 16 is located on the periphery of the mixed flow zone 15 and the reaction zone 14, and is used for bonding the sealing film.

[0093] Figure 4 FIG. 1 is a schematic structural diagram of a partial longitudinal cross section of a fuel cell unit of this embodiment. Figure 4 As shown, the first and second sealing films 10, 12 are designed to have a width of 5 mm in the x-direction to prevent gas leakage during single-cell operation. The outermost layers of the first and second sealing films 10, 12 are typically coated with centrifugal membranes to prevent contamination and damage. These membranes are removed before use. The adhesive layer typically has initial tack, and the thickness of the film material must remain constant before and after curing. Furthermore, the cured film must maintain a certain degree of elasticity to accommodate thermal expansion and contraction during stack operation.

[0094] In addition, cathode and anode sealing films are attached to both sides. The frames of the anode and cathode mixing zones 15 can be composed of multiple layers of frames, forming a multi-layer composite structure. The fuel cell unit 4 achieves precise height control between the reaction zone 14, mixing structure zone 15, and sealing structure zone 16 of the plate, ensuring close and uniform contact between the cathode plate 9, first sealing film 10, membrane electrode 11, second sealing film 12, and plate during the hot pressing process. This prevents damage to the battery due to local overpressure and improves the stability and durability of the overall structure.

[0095] The cross-sectional shape of the cathode side frame 20 is identical to that of the cathode sealing structure 16; the cross-sectional shape of the anode side frame 22 is identical to that of the anode sealing structure 16; the cross-sectional shape of the first sealing film 10 is identical to that of the cathode sealing structure 16; and the cross-sectional shape of the second sealing film 12 is identical to that of the anode sealing structure 16. A hydrogen inlet, a coolant inlet, and an air inlet are provided at one end of the membrane electrode frame, one end of the cathode plate 9, and one end of the anode plate 13.

[0096] Figure 5 This is a highly schematic diagram of the partial structure of a fuel cell unit in this embodiment. The compressed thickness D1 of the cathode carbon paper 19 is 180 μm, the thickness d1 of the cathode side frame 20 is 130 μm, the thickness difference h1 between the cathode mixing area 15 and the cathode reaction area 14 is 50 μm, and the thickness d2 of the first sealing film 10 is 50 μm, meeting the cathode-side requirement: D1 = d1 + h1 ≥ d1 + d2. The compressed thickness D2 of the anode carbon paper 18 is 180 μm, the thickness d3 of the anode side frame 22 is 180 μm, and the thickness d4 of the second sealing film 12 is 50 μm. The thickness difference h2 between the anode mixing area 15 and the anode reaction area 14 is zero, meeting the anode-side requirement: D2 = d3 + h2 ≤ d3 + d4.

[0097] Figure 6 FIG. 1 is a schematic structural diagram of the cooling field sealing rubber line in the fuel cell monomer of this embodiment; FIG. Figure 6 As shown, the sealant line 5 is used to seal the coolant field. It can be bonded to the cathode plate 9 and anode plate 13 using prefabricated sealant lines and directly injection-molded in situ, ensuring unobstructed coolant flow between the fuel cell cells 4. The coolant field sealant line 5 is typically made of a high-temperature, corrosion-resistant, and durable material, typically silicone rubber, to ensure performance in the fuel cell's operating environment. Furthermore, the sealant line 5 must be precisely designed and sized to ensure a good fit with the coolant field and other components, forming a tight and durable seal.

[0098] Figure 7 FIG. 1 is a cross-sectional schematic diagram of a cooling field sealing line in a fuel cell unit of this embodiment; FIG. Figure 7 As shown, the cross section of the sealing rubber line 5 adopts a double-seal design including an inner and outer sealing structure. Such double protection can effectively prevent the leakage of gas or liquid, especially in high pressure, high temperature or extreme environments, providing a more reliable sealing effect.

[0099] The back of the sealing structure area 16 is a glue line sealing groove for the cooling liquid field, which is used to seal the cooling field. Prefabricated glue lines can be used for pasting and in-situ direct injection molding on the plate, while ensuring that the coolant flow channel between the single cells is unobstructed.

[0100] The fuel cell monomer 4 of this embodiment has high structural strength, is easy to disassemble and assemble, and has high stacking efficiency.

[0101] In this embodiment, the general steps for preparing a fuel cell unit 4 are as follows: the first sealing film 10 and the second sealing film 12 are simultaneously adhered to the frame during the fabrication of the membrane electrode 11. The centrifugal membrane on the anode side is peeled off and placed on the anode plate 13 through the positioning hole 17. The centrifugal membrane on the cathode side is peeled off and the cathode plate 9 is placed on top. The anode plate 13, membrane electrode 11, and cathode plate 9 are aligned through the positioning holes 17 and cold-pressed using a tooling according to the set pressure and time to form a preliminary single cell. The preliminary single cell is then hot-pressed according to the set hot-pressing temperature, pressure, and time to form an integrated fuel cell unit 4. Using both cold-pressing and hot-pressing processes, the pressure, time, and temperature parameters are set appropriately based on the material properties to complete the single cell fabrication. This designed single cell fabrication method facilitates repeatable fabrication and industrial production. Furthermore, the adhesive seal between the plate and membrane electrode 11 ensures consistent single cell fabrication during mass production.

[0102] The specific preparation steps of the above fuel cell monomer are as follows:

[0103] (1) A membrane electrode 11 is placed on the upper surface of the anode plate 13, with the anode catalyst layer side of the membrane electrode 11 facing downward; a gas flow channel is provided on the upper surface of the anode plate 13 for the flow of hydrogen and liquid water; a reaction zone 14 cooperates with the anode carbon paper 18 for the diffusion of hydrogen and the circulation of water; a sealing structure area 16 is provided on the upper surface of the anode plate 13, which is bonded to the second sealing film 12 for sealing and support; a coolant flow channel is provided on the lower surface of the anode plate 13 for the flow of coolant to remove the generated heat; the outermost layer of the anode side frame 22 of the membrane electrode 11 is provided with the second sealing film 12, and the centrifugal film of the second sealing film 12 is removed before placement.

[0104] (2) The cathode plate 9 is sequentially placed on the cathode catalyst layer side of the membrane electrode 11; the lower surface of the cathode plate 9 contacts the cathode side of the membrane electrode 11, and a gas flow channel is provided on the lower surface of the cathode plate 9 for the flow of air and liquid water; the reaction area 14 cooperates with the cathode carbon paper 19 for the diffusion of air and the circulation of water; the lower surface of the cathode plate 9 is provided with a sealing structure area 16, which is bonded to the first sealing film 10 for sealing and support; the upper surface of the cathode plate 9 is provided with a coolant flow channel for the flow of coolant to take away the generated heat.

[0105] (3) Cold pressing the cathode plate 9, the first sealing film 10, the membrane electrode 11, the second sealing film 12, and the anode plate 13 at a set pressure of 0.6 to 1.0 MPa and a time of 15 seconds to obtain a preliminary fuel cell monomer 4;

[0106] (4) According to the set hot pressing temperature of 100-150°C, pressure of 0.6-1.0 MPa, and time of 60 seconds, the first sealing film 10 and the second sealing film 12 are made of polyolefin, and the preliminary fuel cell monomer 4 is hot pressed to obtain the final integrated fuel cell monomer 4.

[0107] (5) The cathode plate 9 and the anode plate 13 are made of a composite substrate of existing metal and graphite. The molding process can be realized by any molding process, including but not limited to molding, stamping, machining and etching. However, the selection of sealing materials and processes may vary depending on the substrate material.

[0108] Figure 8 Schematic diagram of the structure of the hot pressing tooling for the anode plate in the fuel cell monomer of this embodiment; the anode plate tooling 23 is installed at the lower part of the hot pressing table, which can be used to place the anode plate 13. The back of the sealing structure area 16 of the anode plate 13 is in contact with the hot pressing surface 24, which can conduct heat and be subjected to pressure, so that the cathode plate 9 and the sealing structure area 16 of the anode plate 13 are respectively bonded to the first sealing film 10 and the second sealing film 12; the upper hot pressing tooling corresponds to the cathode plate 9, contacts the cathode plate 9 during hot pressing, which can conduct heat and be subjected to pressure, so that the sealing structure area 16 of the cathode plate 9 and the anode plate 13 are respectively bonded to the first sealing film 10 and the second sealing film 12; the upper and lower installation positions of the hot pressing tooling are not restricted and correspond to the placement order of the plates; there are at least two positioning holes 17 on the tooling, which can fix the cathode and anode plates 13 and the membrane electrode 11, the first sealing film 10 and the second sealing film 12 on the tooling.

[0109] In traditional designs, the alignment and sealing between the membrane electrode 11 and the electrode plate rely on a separate clamping force and a sealing rubber line 5. This approach is prone to problems such as alignment deviation between the membrane electrode 11 and the electrode plate, poor sealing, and uneven assembly pressure in high-power, multi-cell stacks. The present invention simplifies the single-cell manufacturing process by hot-pressing the anode and cathode plates 13 and the membrane electrode 11 in one step, improving production efficiency and cell consistency. If a cell in a fuel cell stack experiences a problem, it can be disassembled and replaced, which is easy to operate and will not affect the reassembly and use of other cells.

[0110] The fuel cell monomer is a highly reliable integrated single-cell structure. Through the sealing film bonding technology, it achieves a close combination of the plate and the membrane electrode, which can effectively improve the assembly accuracy and efficiency, and the sealing performance, while reducing the pressure requirements during assembly; moreover, the fuel cell monomer can effectively avoid overpressure of the membrane electrode causing the carbon paper to be embedded in the plate flow channel, and even mechanical damage in severe cases.

[0111] Example 2

[0112] This embodiment discloses a fuel cell stack, Figure 9The fuel cell stack of this embodiment is a schematic diagram of the structure. The fuel cell stack includes a first current collecting plate 3, a first insulating top plate 2, a first end plate 1, a second current collecting plate 6, a second insulating top plate 7, a second end plate 8, and the fuel cell 4 described above. The first current collecting plate 3, the first insulating top plate 2, and the first end plate 1 are sequentially arranged from the cathode plate 9 of the fuel cell 4 outward. The second current collecting plate 6, the second insulating top plate 7, and the second end plate 8 are sequentially arranged from the anode plate 13 of the fuel cell 4 outward.

[0113] The fuel cell stack is composed of a plurality of single cells stacked in series, and the completed single cells are assembled by positioning according to production requirements.

[0114] In conventional designs, alignment and sealing between the membrane electrode 11 and the electrode plates rely on separate clamping forces and sealant lines 5. This approach is prone to problems such as misalignment between the membrane electrode 11 and the electrode plates, poor sealing, and uneven assembly pressure in high-power, multi-cell stacks, leading to reduced stack performance and shortened service life. The integrated fuel cell monomers 4 stacked in the present invention can effectively reduce assembly tolerances during fuel cell stack assembly and improve stacking efficiency.

[0115] The structure of the fuel cell cells 4 is designed to assemble a high-power, multi-cell stack based on power and cell count requirements. Coolant flow spaces are created between the fuel cell cells 4. When using sealant lines 5 for sealing, the sealant lines 5 are designed to have a certain degree of elasticity, allowing them to fill the gaps between components when compressed, creating a tight contact. A fuel cell stack can be constructed by stacking the aforementioned integrated fuel cell cells 4 in sequence, with adjacent locations affixed with water field sealant lines 5 or directly injection molded.

[0116] Compared with the traditional stacking method, the integrated fuel cell monomer 4 can improve the stacking efficiency and assembly accuracy; because the electrode plate, membrane electrode 11 and sealing film have been designed in coordination, there is no need to apply a large pressing force again during the assembly process, which reduces the assembly force of the entire stack and is conducive to the stable operation of the stack.

[0117] Effect Example 1

[0118] This embodiment tests a fuel cell stack composed of three fuel cell monomers as in Example 1, and uses a Qunyi HTS-2000 2kw test bench to test the performance of the stack under a pressing force of 2.40T. Table 1 shows the performance parameters of each of the three cells.

[0119] Table 1

[0120]

[0121] The test results show that the performance of the fuel cell cells in the fuel cell stack is good, with an average fluctuation of about 0.86%, indicating that the consistency of the three cells is good; this shows that the structure of the fuel cell cells and fuel cell stack of this solution is reliable; the fuel cell cells numbered 1 and 3 in the fuel cell stack are located at both ends of the stack, and their voltage is slightly lower than that of the middle cell, which is a normal phenomenon.

[0122] Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. A fuel cell monomer, characterized in that: It includes a cathode plate, a membrane electrode and an anode plate stacked in sequence; The membrane electrode comprises a proton exchange membrane and a membrane electrode frame; the membrane electrode frame comprises an anode side frame and a cathode side frame, the anode side frame and the cathode side frame being bonded to each other to form a receiving cavity, and the proton exchange membrane is embedded in the receiving cavity; the cathode side frame and the anode side frame are respectively provided with a first hollow portion and a second hollow portion; cathode carbon paper is provided on the surface of the proton exchange membrane located in the first hollow portion, and anode carbon paper is provided on the surface of the proton exchange membrane located in the second hollow portion; The cathode plate includes a cathode reaction area, a cathode mixing area and a cathode sealing structure area, wherein the cathode mixing area is arranged at the outer edge of the cathode reaction area, and the cathode sealing structure area is arranged around the periphery of the cathode mixing area; the thickness of the cathode sealing structure area is smaller than that of the cathode mixing area; a first sealing film is provided between the cathode sealing structure area and the cathode side frame; The anode plate includes an anode reaction area, an anode mixed flow area and an anode sealing structure area. The anode mixed flow area is arranged at the outer edge of the anode reaction area, and the anode sealing structure area is arranged around the periphery of the anode mixed flow area; the thickness of the anode sealing structure area is less than the thickness of the anode mixed flow area; a second sealing film is provided between the anode sealing structure area and the anode side frame.

2. The fuel cell monomer according to claim 1, wherein: The thickness of the first sealing film is 25-75 μm; The thickness of the second sealing film is 25-75 μm.

3. The fuel cell monomer according to claim 1, wherein: The thickness of the cathode carbon paper satisfies: D1=d1+d2≥d1+h1; wherein the thickness of the cathode carbon paper is D1, d1 is the thickness of the cathode side frame, d2 is the thickness of the first sealing film, and h1 is the difference in thickness between the cathode mixing area and the cathode reaction area; The thickness of the anode carbon paper satisfies: D2=d3+h2≤d3+d4; wherein the thickness of the anode carbon paper is D2, d3 is the thickness of the anode side frame, d4 is the thickness of the second sealing film, and h2 is the thickness difference between the anode mixed flow area and the anode reaction area.

4. The fuel cell monomer according to claim 1, wherein: The width of the first sealing adhesive film and the width of the second sealing adhesive film are both 3-8 mm.

5. The fuel cell monomer according to claim 1, wherein: The cross-sectional shape of the cathode side frame is the same as the cross-sectional shape of the cathode sealing structure area; The cross-sectional shape of the anode side frame is the same as the cross-sectional shape of the anode sealing structure area.

6. The fuel cell monomer according to claim 5, wherein: The cross-sectional shape of the first sealing film is the same as the cross-sectional shape of the cathode sealing structure area; The cross-sectional shape of the second sealing adhesive film is the same as the cross-sectional shape of the anode sealing structure area.

7. The fuel cell monomer according to claim 1, wherein: One end of the membrane electrode frame, one end of the cathode plate, and one end of the anode plate are all provided with a hydrogen inlet, a coolant inlet, and an air inlet.

8. The fuel cell monomer according to claim 7, wherein: The fuel cell unit further includes a sealing rubber line, and the sealing rubber line is arranged on the outer edge of the fuel cell unit.

9. The fuel cell monomer according to claim 1, wherein: The cathode plate and the anode plate are made of metal, graphite, or a composite material of metal and graphite.

10. A fuel cell stack, characterized in that: The fuel cell stack includes a first current collecting plate, a first insulating top plate, a first end plate, a second current collecting plate, a second insulating top plate, a second end plate, and a fuel cell unit according to any one of claims 1 to 9; the first current collecting plate, the first insulating top plate, and the first end plate are sequentially provided from the cathode plate of the fuel cell unit to the outside; the second current collecting plate, the second insulating top plate, and the second end plate are sequentially provided from the anode plate of the fuel cell unit to the outside.

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