Integrated single fuel cell structure
By setting gas inlet and outlet chambers on the monopole plate and using a combination of hydrophobic carbon paper and sealing gaskets, the problems of uneven force distribution and low positioning accuracy during the assembly process of fuel cell stacks are solved, achieving efficient assembly and performance improvement of fuel cells.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SHENZHEN ACAD OF AEROSPACE TECH
- Filing Date
- 2024-12-16
- Publication Date
- 2026-06-18
AI Technical Summary
In existing fuel cell stacks, uneven force distribution and low positioning accuracy exist during the assembly of membrane electrode assembly and bipolar plates, leading to problems such as decreased stack performance and uneven heat distribution.
The integrated single-cell fuel cell structure is adopted. By setting gas inlet and gas outlet chambers on both sides of the single plate and using hydrophobic carbon paper and sealing gaskets, an integrated sealed structure is formed to ensure that each component is subjected to uniform force and is accurately positioned during assembly.
This achieves uniform stress and precise positioning of internal components of the fuel cell, improves the stack's airtightness and voltage consistency, simplifies the assembly process, and reduces costs.
Smart Images
Figure CN2024139582_18062026_PF_FP_ABST
Abstract
Description
An integrated single-cell fuel cell structure Technical Field
[0001] This invention relates to the field of battery technology, and in particular to an integrated single-cell fuel cell structure. Background Technology
[0002] Fuel cells can directly convert chemical energy into electrical energy, and their energy conversion efficiency is usually higher than that of traditional combustion power generation methods. Their emissions are mainly water and do not produce greenhouse gases or other pollutants, making them a clean energy technology.
[0003] A fuel cell stack consists of multiple individual cells, each of which is the basic working unit of the stack. A single cell typically includes a membrane electrode assembly (MEA), bipolar plates, and seals. The seals prevent leakage between reactant gases and coolant, ensuring the stack's airtightness.
[0004] In existing fuel cell stacks, the commonly used sealing method involves mounting sealing rings on the membrane electrode assembly (MEA) or bipolar plates. Structurally, the MEA and bipolar plates are separate and require alternating stacking during assembly, with sealing achieved by applying clamping forces. However, this arrangement results in uneven force distribution along the longitudinal direction of the MEA and bipolar plates, making precise control of assembly dimensions and the compression characteristics of the MEA's active region difficult. Laterally, different components of a single cell or different areas of the same component experience uneven forces. Furthermore, as the number of stacked layers increases, the positioning accuracy of the MEA and bipolar plates decreases, affecting the overall performance of the stack, leading to uneven heat distribution within the stack, reduced voltage consistency across individual cells, and accelerated performance degradation. Summary of the Invention
[0005] To address the problems mentioned above, the present invention provides an integrated single-cell fuel cell structure in which the internal components are subjected to uniform stress during assembly and stacking, and the membrane electrode and electrode plates have high positioning accuracy.
[0006] The solution adopted by the present invention to solve its technical problem is: an integrated single-cell fuel cell structure, including a single plate and a membrane electrode assembly, wherein a gas inlet chamber and a gas outlet chamber are respectively provided on both sides of the single plate;
[0007] The monopolar plate includes an anode monopolar plate and a cathode monopolar plate, and the membrane electrode is fixed and sealed between the anode monopolar plate and the cathode monopolar plate by hot pressing;
[0008] The anode monopolar plate is bonded with a sealing gasket A by a highly conductive adhesive. The sealing gasket A is fixed to the periphery of the anode monopolar plate. A hydrophobic carbon paper is fixedly connected between the gas inlet chamber and the gas outlet chamber of the anode monopolar plate.
[0009] A sealing gasket B is attached to the cathode monopolar plate with highly conductive adhesive. Two sealing gaskets B are provided and fixed to the periphery of the gas inlet chamber and gas outlet chamber of the cathode monopolar plate, respectively. Hydrophobic carbon paper is fixedly connected between the two sealing gaskets B.
[0010] Both the anode and cathode monopolar plates have flow channels in the hydrophobic carbon paper.
[0011] Furthermore, the flow channel is one of a parallel flow channel, a serpentine flow channel, an interdigitated flow channel, or a spiral flow channel.
[0012] Furthermore, the porosity of the hydrophobic carbon paper is 20%-90%, and the thickness of the hydrophobic carbon paper is 50-600μm; on a horizontally placed anode monopolar plate, the top height of the hydrophobic carbon paper and the top height of the sealing gasket A are located on the same horizontal plane; on a horizontally placed cathode monopolar plate, the top height of the hydrophobic carbon paper and the top height of the sealing gasket B are located on the same horizontal plane.
[0013] Furthermore, the membrane electrode includes a proton exchange membrane, with catalytic layers disposed on both sides of the proton exchange membrane, a frame membrane disposed on the side of the catalytic layer away from the proton exchange membrane, and a gas diffusion layer disposed on the side of the frame membrane away from the catalytic layer.
[0014] Furthermore, the border film is one or more of PEN, PET, and PPS, and the thickness of the border film is 40-200 μm.
[0015] Furthermore, the monopolar plate is a metal sheet, the surface of which is coated with a highly conductive coating, and the thickness of the metal sheet is 0.1 to 100 mm.
[0016] Furthermore, the highly conductive coating is one or two of carbon coating, gold coating, and titanium coating, and the thickness of the highly conductive coating is 1 nm to 100 μm.
[0017] Furthermore, the highly conductive adhesive is one or more of carbon paste adhesive, epoxy resin conductive adhesive, and electronically conductive silver paste.
[0018] In summary, the beneficial effects of the present invention are as follows: The single fuel cell of this application does not have a sealing ring. Instead, by optimizing the combination of the sealing gasket and the electrode plate and hot-pressing, the single cell forms a sealed structure, which ensures the airtightness of the stack and also enables the single electrode plate and the membrane electrode to be accurately docked and precisely positioned during assembly and stacking.
[0019] Hydrophobic carbon paper, together with sealing gaskets, is placed at different positions on the anode and cathode monopole plates. The optimized partitioning of the hydrophobic carbon paper and sealing gaskets makes it easier to assemble individual cells, while the structural distribution of the components inside the cell is more flat, making the stress on the components inside the cell more uniform when the cell is stacked.
[0020] The hydrophobic carbon paper is provided with flow channels, which can form excellent water and gas mass transfer channels, thereby meeting the water and gas management requirements of fuel cells during operation.
[0021] The hydrophobic carbon paper has pores inside. After being compressed, the groove and ridge structure on its flow channel is more loose than the groove and ridge structure on the electrode plate. This is more conducive to gas and liquid transport, as well as the precise positioning and uniform compression of the membrane electrode and the electrode plate. At the same time, it eliminates the step of etching the flow channel on the electrode plate, reducing costs and simplifying the process.
[0022] Furthermore, the single-cell fuel cell of this application facilitates the rapid assembly of subsequent fuel cell stacks and the rapid testing and replacement of individual membrane electrode assemblies.
[0023] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description
[0024] Figure 1 is a schematic diagram of the structure of the single-pole plate in this embodiment;
[0025] Figure 2 is a schematic diagram of the anode flow field plate in this embodiment;
[0026] Figure 3 is a schematic diagram of the cathode flow field plate in this embodiment;
[0027] Figure 4 is a schematic diagram of the membrane electrode structure in this embodiment.
[0028] In the diagram: 1. Monopolar plate; 2. Gas inlet chamber; 3. Gas outlet chamber; 4. Sealing gasket A; 5. Sealing gasket B; 6. Membrane electrode with a seven-in-one structure; 7. Hydrophobic carbon paper. Detailed Implementation
[0029] The single-cell fuel cell of this application is achieved through the following steps:
[0030] (1) Preparation of monopolar plate 1: Take a metal sheet, and set a gas inlet chamber 2 and a gas outlet chamber 3 on both sides of the metal sheet respectively. Apply a highly conductive coating to the surface of the metal sheet by chemical or physical deposition method to form monopolar plate 1.
[0031] (2) Setting an anode flow channel layer on the monopolar plate 1: Take a monopolar plate 1, as shown in Figure 2, and use highly conductive adhesive to bond the sealing gasket A4 to the periphery of the monopolar plate 1. Then, fix the hydrophobic carbon paper 7 between the gas inlet chamber 2 and the gas outlet chamber 3 as a hydrogen flow channel layer, thereby forming a monopolar plate with an anode flow channel layer, i.e., an anode flow field plate. Wherein, when the anode flow field plate is placed horizontally, the top height of the hydrophobic carbon paper and the top height of the sealing gasket A are on the same horizontal plane.
[0032] (3) A cathode flow channel layer is formed on the monopolar plate 1: Take a monopolar plate 1, as shown in Figure 3, and use highly conductive adhesive to bond the sealing gasket B5 to the periphery of the gas inlet chamber 2 and the gas outlet chamber 3 of the monopolar plate 1. Then, use highly conductive adhesive to fix the hydrophobic carbon paper 7 to the middle area of the two sealing gaskets B5 as an air flow channel layer, thereby forming a monopolar plate with a cathode flow channel layer, i.e., a cathode flow field plate. Wherein, when the anode flow field plate is placed horizontally, the top height of the hydrophobic carbon paper and the top height of the sealing gasket B are on the same horizontal plane.
[0033] (4) Preparation of membrane electrode: A certain amount of catalyst, ionomer solution and solvent are weighed according to the stoichiometric ratio, dispersed to form a catalyst layer slurry, and then coated on both sides of the proton exchange membrane by coating. After drying, a three-layer structure of catalyst-coated membrane (CCM) of anode catalyst layer-proton exchange membrane-cathode catalyst layer is formed. Subsequently, the prepared CCM is encapsulated into two frame membranes by hot pressing to form a five-in-one membrane electrode. Then, the gas diffusion layer is attached to both sides of the five-in-one membrane electrode by dispensing to form a seven-in-one membrane electrode 6. As shown in Figure 4, the membrane electrode of this application is compatible with the structure of the anode flow field plate and the cathode flow field plate.
[0034] (5) Preparation of integrated single fuel cell: Apply highly conductive adhesive to the surface of the sealing gasket A4 of the anode flow field plate and apply highly conductive adhesive to the surface of the sealing gasket B5 with the cathode flow field plate. Then, the anode and cathode of the membrane electrode 6 with the seven-in-one structure obtained in step (4) are respectively aligned with the cathode flow field plate and the anode flow field plate, and are assembled into an integrated single fuel cell by pressing assembly.
[0035] This application utilizes hydrophobic carbon paper 7 as a flow field layer, with flow channels and grooves within it. Combined with the porous structure of the hydrophobic carbon paper 7, this creates excellent water-gas mass transfer channels, thus meeting the water-gas management requirements of hydrogen fuel cells during operation. Simultaneously, by sequentially stacking a cathode gas diffusion layer, a cathode catalyst layer, a proton exchange membrane, an anode catalyst layer, and an anode diffusion layer between the anode and cathode flow field plates, and then hot-pressing them together, an integrated membrane electrode assembly (MEA) is formed. This design avoids and solves the problems of low positioning accuracy and uneven compression caused by the alternating stacking of the MEA and bipolar plates during fuel cell stack assembly. It also eliminates the step of etching flow channels on the plates, thereby reducing costs and simplifying the process. The single-cell combustion battery of this invention enables direct-plug assembly and efficient, low-cost production of fuel cell stacks.
[0036] Example 1
[0037] (1) Preparation of monopolar plate 1: Take a titanium plate with a thickness of 0.8 mm, cut out gas inlet cavity 2 and gas outlet cavity 3 by stamping, and apply a gold coating to the surface of the titanium plate by physical deposition to form monopolar plate 1.
[0038] (2) Set an anode flow channel layer on the monopolar plate 1: Take a monopolar plate 1, use high conductive adhesive to bond a 200μm thick polytetrafluoroethylene (PTFE) sealing gasket A4 to the outside of the monopolar plate 1, and then use high conductive adhesive to fix a 270μm thick hydrophobic carbon paper 7 Toray TGP-H-090 between the gas inlet chamber 2 and the gas outlet chamber 3 as a hydrogen flow channel layer, thereby forming a monopolar plate with an anode flow channel layer, i.e., an anode flow field plate.
[0039] (3) Set a cathode flow channel layer on the monopolar plate 1: Take a monopolar plate 1, use high conductive glue to bond a PTFE sealing gasket B5 with a thickness of 200μm to the gas inlet chamber 2 and gas outlet chamber 3 of the monopolar plate 1, and then fix a 270μm thick hydrophobic carbon paper 7 Toray TGP-H-090 in the middle area of the two sealing gaskets B5 as an air flow channel layer, thereby forming a monopolar plate with a cathode flow channel layer, i.e., a cathode flow field plate.
[0040] (4) Preparation of membrane electrode: HISPEC9100 catalyst and ultrapure water were weighed at a mass ratio of 1:60, mixed evenly, and then dispersed for 30 min using a high-speed shear mill at a speed of 10,000 rpm. Subsequently, 3 g of D520, 3 g of ultrapure water, and 9 g of isopropanol were added, mixed evenly, and then dispersed again for 30 min using a high-speed shear mill at a speed of 10,000 rpm to form a catalyst slurry. The catalyst slurry was then coated onto both sides of the proton exchange membrane by spraying to achieve a target anode Pt loading of 0.1 mg / cm³.2 The cathode Pt loading is 0.4 mg / cm³. 2 After drying, a three-layer catalyst-coated membrane (CCM) with an anode catalyst layer, a proton exchange membrane, and a cathode catalyst layer is formed. The prepared CCM is then encapsulated into two single-layer PEN frames with a thickness of 45 μm by hot pressing to form a five-in-one membrane electrode. Then, the gas diffusion layer Toray TGP-H-055 carbon paper is attached to both sides of the five-in-one membrane electrode by dispensing with highly conductive adhesive to form a seven-in-one membrane electrode 6.
[0041] (5) Preparation of integrated single fuel cell: Apply highly conductive adhesive to the surface of the sealing gasket A4 of the anode flow field plate and apply highly conductive adhesive to the surface of the sealing gasket B5 with the cathode flow field plate. Then, the anode and cathode of the membrane electrode 6 with the seven-in-one structure obtained in step (4) are respectively aligned with the cathode flow field plate and the anode flow field plate, and are assembled into an integrated single fuel cell by pressing assembly.
[0042] In this embodiment, the highly conductive adhesive is mainly composed of polyvinylidene fluoride (PVDF), highly conductive carbon black, 1-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), and water.
[0043] Example 2
[0044] (1) Preparation of monopolar plate 1: Take a titanium plate with a thickness of 0.4 mm, cut out gas inlet chamber 2 and gas outlet chamber 3 by stamping, and coat the surface of the titanium plate with a carbon coating by chemical vapor deposition to form monopolar plate 1.
[0045] (2) Setting an anode flow channel layer on a single plate 1: Take a single plate 1, use high conductive adhesive to bond a silicone sealing gasket A4 with a thickness of 100μm to the periphery of the single plate 1, and then use high conductive adhesive to fix a hydrophobic carbon paper 7 with a thickness of 190μm, Toray TGP-H-060, between the gas inlet chamber 2 and the gas outlet chamber 3 as a hydrogen flow channel layer, and cut parallel flow channels on the hydrophobic carbon paper 7 by die-cutting, thereby forming a single plate 1 with an anode flow channel layer, i.e., an anode flow field plate.
[0046] (3) Set a cathode flow channel layer on the monopolar plate 1: Take a monopolar plate 1, use high conductive adhesive to bond a silicone sealing gasket B5 with a thickness of 200μm to the outer periphery of the gas inlet chamber 2 and the gas outlet chamber 3 of the monopolar plate 1, and then fix a hydrophobic carbon paper 7 Toray TGP-H-090 with a thickness of 270μm to the middle area of the two sealing gaskets B5 as an air flow channel layer, and cut the matching flow channel on the hydrophobic carbon paper 7 by die cutting, thereby forming a monopolar plate 1 with a cathode flow channel layer, i.e., a cathode flow field plate.
[0047] (4) Preparation of membrane electrode: HISPEC9100 catalyst and ultrapure water were weighed at a mass ratio of 1:5, mixed evenly, and dispersed for 30 min using a high-speed shear mill at a speed of 12000 rpm; then 2 g of D2020, 3 g of ultrapure water, and 2 g of isopropanol were added, mixed evenly, and dispersed for 30 min using a high-speed shear mill at a speed of 12000 rpm to form a catalyst slurry; then the slurry was coated on both sides of the proton exchange membrane using a slit coating method to achieve a target anode Pt loading of 0.1 mg / cm³. 2 The cathode Pt loading is 0.4 mg / cm³. 2 After drying, a three-layer catalyst-coated membrane (CCM) with an anode catalyst layer, a proton exchange membrane, and a cathode catalyst layer is formed. The prepared CCM is then encapsulated into two single-layer PEN frames with a thickness of 45 μm by hot pressing to form a five-in-one membrane electrode. Then, the gas diffusion layer Toray TGP-H-055 carbon paper is glued to both sides of the five-in-one membrane electrode by dispensing to form a seven-in-one membrane electrode 6.
[0048] (5) Preparation of integrated single fuel cell: Apply highly conductive adhesive to the surface of the sealing gasket A4 of the anode flow field plate and apply highly conductive adhesive to the surface of the sealing gasket B5 with the cathode flow field plate. Then, the anode and cathode of the membrane electrode 6 with the seven-in-one structure obtained in step (4) are respectively aligned with the cathode flow field plate and the anode flow field plate, and are assembled into an integrated single fuel cell by pressing assembly.
[0049] Specifically, in this embodiment, the conductive filler in the carbon coating is graphene.
[0050] Alternatively, in addition to graphene, the conductive filler in the carbon coating can also be activated carbon, graphite, or carbon fiber.
[0051] In this embodiment, the highly conductive adhesive is an epoxy resin conductive adhesive.
[0052] Example 3
[0053] (1) Preparation of monopolar plate 1: Take a 316 stainless steel plate with a thickness of 0.8mm, cut out gas inlet chamber 2 and gas outlet chamber 3 by stamping, and coat the surface of the titanium plate with a titanium coating by chemical vapor deposition to form monopolar plate 1.
[0054] (2) Setting an anode flow channel layer on a single plate 1: Take a single plate 1, use high conductive adhesive to bond a silicone sealing gasket A4 with a thickness of 100μm to the periphery of the single plate 1, and then use high conductive adhesive to fix a hydrophobic carbon paper 7 Toray TGP-H-060 with a thickness of 190μm between the gas inlet chamber 2 and the gas outlet chamber 3 as a hydrogen flow channel layer, and cut a serpentine flow channel on the hydrophobic carbon paper 7 by die-cutting, thereby forming a single plate 1 with an anode flow channel layer, i.e., an anode flow field plate.
[0055] (3) Set a cathode flow channel layer on the monopolar plate 1: Take a monopolar plate 1, use high conductive glue to bond a silicone sealing gasket B5 with a thickness of 100μm to the outer periphery of the gas inlet chamber 2 and the gas outlet chamber 3 of the monopolar plate 1, and then fix a hydrophobic carbon paper 7 Toray TGP-H-060 with a thickness of 190μm to the middle area of the two sealing gaskets B5 as an air flow channel layer, and cut the matching flow channel on the hydrophobic carbon paper 7 by die cutting, thereby forming a monopolar plate 1 with a cathode flow channel layer, i.e., a cathode flow field plate.
[0056] (4) Preparation of membrane electrode: HISPEC9100 catalyst and ultrapure water were weighed at a mass ratio of 1:5, mixed evenly, and dispersed for 30 min using a high-speed shear mill at a speed of 13000 rpm; 2 g of D2020, 3 g of ultrapure water, and 2 g of isopropanol were added, mixed evenly, and dispersed for 30 min using a high-speed shear mill at a speed of 13000 rpm to form a catalyst slurry; then, it was coated on both sides of the proton exchange membrane using a slit coating method to achieve a target anode Pt loading of 0.1 mg / cm³. 2 The cathode Pt loading is 0.4 mg / cm³. 2 After drying, a three-layer catalyst-coated membrane (CCM) with an anode catalyst layer, a proton exchange membrane, and a cathode catalyst layer is formed. The prepared CCM is then encapsulated into two single-layer PEN frames with a thickness of 45 μm by hot pressing to form a five-in-one membrane electrode. Then, the gas diffusion layer JNTG-BA5C1 carbon paper is attached to both sides of the five-in-one membrane electrode by dispensing with highly conductive adhesive to form a seven-in-one membrane electrode 6.
[0057] (5) Preparation of integrated single fuel cell: Apply highly conductive adhesive to the surface of the sealing gasket A4 of the anode flow field plate and apply highly conductive adhesive to the surface of the sealing gasket B5 with the cathode flow field plate. Then, the anode and cathode of the membrane electrode 6 with the seven-in-one structure obtained in step (4) are respectively aligned with the cathode flow field plate and the anode flow field plate, and are assembled into an integrated single fuel cell by pressing assembly.
[0058] In this embodiment, the highly conductive adhesive is electronically conductive silver paste.
[0059] The embodiments described above are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and modifications made by those skilled in the art based on the invention shall fall within the scope of protection of the present invention.
Claims
1. An integrated single-cell fuel cell structure, comprising a single electrode plate and a membrane electrode assembly, characterized in that: The single electrode plate is provided with a gas inlet chamber and a gas outlet chamber on both sides; The monopolar plate includes an anode monopolar plate and a cathode monopolar plate, and the membrane electrode is fixed and sealed between the anode monopolar plate and the cathode monopolar plate by hot pressing; The anode monopolar plate is bonded with a sealing gasket A by a highly conductive adhesive. The sealing gasket A is fixed to the periphery of the anode monopolar plate. A hydrophobic carbon paper is fixedly connected between the gas inlet chamber and the gas outlet chamber of the anode monopolar plate. A sealing gasket B is attached to the cathode monopolar plate with highly conductive adhesive. Two sealing gaskets B are provided and fixed to the periphery of the gas inlet chamber and gas outlet chamber of the cathode monopolar plate, respectively. Hydrophobic carbon paper is fixedly connected between the two sealing gaskets B. Both the anode and cathode monopolar plates have flow channels in the hydrophobic carbon paper.
2. The integrated single-cell fuel cell structure according to claim 1, characterized in that, The flow channel is either a parallel flow channel or a serpentine flow channel.
3. The integrated single-cell fuel cell structure according to claim 1, characterized in that, The porosity of the hydrophobic carbon paper is 20%-90%, and the thickness of the hydrophobic carbon paper is 50-600μm. On a horizontally placed anode monopolar plate, the top height of the hydrophobic carbon paper and the top height of the sealing gasket A are on the same horizontal plane; on a horizontally placed cathode monopolar plate, the top height of the hydrophobic carbon paper and the top height of the sealing gasket B are on the same horizontal plane.
4. The integrated single-cell fuel cell structure according to claim 1, characterized in that, The membrane electrode includes a proton exchange membrane, with catalytic layers disposed on both sides of the proton exchange membrane. A frame membrane is disposed on the side of the catalytic layer away from the proton exchange membrane, and a gas diffusion layer is disposed on the side of the frame membrane away from the catalytic layer.
5. The integrated single-cell fuel cell structure according to claim 4, characterized in that, The border film is one or more of PEN, PET, and PPS, and the thickness of the border film is 40-200 μm.
6. The integrated single-cell fuel cell structure according to claim 1, characterized in that, The single-electrode plate is a metal sheet, the surface of which is coated with a highly conductive coating, and the thickness of the metal sheet is 0.1 to 100 mm.
7. The integrated single-cell fuel cell structure according to claim 6, characterized in that, The highly conductive coating is one or two of carbon coating, gold coating, and titanium coating, and the thickness of the highly conductive coating is 1 nm to 100 μm.
8. The integrated single-cell fuel cell structure according to claim 1, characterized in that, The highly conductive adhesive is one or more of the following: carbon paste adhesive, epoxy resin conductive adhesive, and electronic conductive silver paste.