Membrane electrode and its preparation method, fuel cell

Abstract

This invention relates to a membrane electrode assembly (MEA), its fabrication method, and a fuel cell. The MEA includes a CCM structure, an anode sealing layer, and a cathode sealing layer. The CCM structure includes a proton exchange membrane (PEM), an anode catalyst layer, and a cathode catalyst layer. The anode sealing layer covers the edge of the anode catalyst layer, and the cathode sealing layer covers the edge of the cathode catalyst layer. The edges of the anode sealing layer and the cathode sealing layer on the anode catalyst layer are offset. This reduces the shear force exerted on the PEM by the anode and cathode sealing layers, effectively mitigating the decline in the mechanical properties of the PEM under high and low humidity cycling conditions. Furthermore, because the edges of the anode and cathode sealing layers are offset, the asymmetry between the anode and cathode catalyst layers prevents chemical reactions in the interface cavity, creating an inert region. This effectively solves the problem of chemical degradation of the catalyst and proton exchange membrane caused by free radicals, thereby improving the lifespan of the MEA.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a membrane electrode and its preparation method, and a fuel cell. Background Technology

[0002] The membrane electrode assembly (MEA) is an important component of a fuel cell, serving as the site of electrochemical reactions. It accounts for more than 60% of the cost of a fuel cell and essentially determines its performance, lifespan, and cost.

[0003] A membrane electrode consists of a proton exchange membrane, a catalyst layer, a frame, and a gas diffusion layer. Currently, the mainstream method for preparing membrane electrodes is to first coat both sides of the proton exchange membrane with a catalyst slurry to obtain a Catalyst Coated Membrane (CCM) structure. Then, the frame is sealed to both sides of the CCM structure via hot pressing to form a five-in-one membrane electrode. Finally, the gas diffusion layer is encapsulated on both sides of the five-in-one membrane electrode to obtain a seven-in-one membrane electrode.

[0004] For fuel cells in commercial vehicles, improving the lifespan of the membrane electrode assembly (MEA) is one of the most critical issues for widespread application. MEA performance degradation leads to uneven discharge current within the MEA region, ultimately causing the entire MEA to fail. In practical applications, the most severe performance degradation has been observed at the edge where the CCM structure meets the frame. The main reasons include: 1. Stress concentration at the edge of the CCM structure-frame interface results in significant shear force on the proton exchange membrane, causing a decline in its mechanical properties; 2. Due to the thickness of the frame, a cavity exists at the interface between the CCM structure, frame, and gas diffusion layer after the gas diffusion layer covers the frame and CCM structure. This cavity accelerates the degradation of the proton exchange membrane and the dissolution and aggregation of the platinum catalyst at the interface during commercial vehicle startup, shutdown, idling, and high-potential dynamic cycling, severely reducing MEA durability. Summary of the Invention

[0005] Therefore, it is necessary to address the issue of accelerated membrane electrode performance degradation during commercial vehicle startup, parking, idling, and high-potential dynamic cycling processes by providing a membrane electrode, its preparation method, and a fuel cell to improve the lifespan of the membrane electrode.

[0006] One objective of this invention is to provide a membrane electrode assembly for a fuel cell, as follows:

[0007] A membrane electrode assembly for a fuel cell includes a CCM structure, an anode sealing layer, and a cathode sealing layer. The CCM structure includes a proton exchange membrane and an anode catalyst layer and a cathode catalyst layer respectively disposed on both sides of the proton exchange membrane. The anode sealing layer covers the edge of the anode catalyst layer, and the cathode sealing layer covers the edge of the cathode catalyst layer. The anode sealing layer and the cathode sealing layer are adhered to each other to encapsulate the edge of the CCM structure. The edge of the anode sealing layer on the anode catalyst layer is offset from the edge of the cathode sealing layer on the cathode catalyst layer.

[0008] In one embodiment, the distance between the edge of the anode sealing layer on the anode catalyst layer and the edge of the cathode sealing layer on the cathode catalyst layer is 0.8 mm to 1.6 mm.

[0009] In one embodiment, the area of ​​the anode catalyst layer not covered by the anode sealing layer is larger than the area of ​​the cathode catalyst layer not covered by the cathode sealing layer.

[0010] In one embodiment, the membrane electrode further includes an anolyte gas diffusion layer and / or a cathode gas diffusion layer, wherein the anolyte gas diffusion layer covers the anolyte catalyst layer and the anolyte sealing layer, and the cathode gas diffusion layer covers the cathode catalyst layer and the cathode sealing layer.

[0011] In one embodiment, a first sealant is provided at the junction of the anode gas diffusion layer, the anode catalyst layer, and the anode sealing layer; and / or

[0012] A second sealant is provided at the junction of the cathode gas diffusion layer, the cathode catalyst layer, and the cathode sealing layer.

[0013] In one embodiment, the first sealant is selected from at least one of epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide, and polyetherimide.

[0014] The second sealant is selected from at least one of silicone, polyacrylic acid, polyisobutylene, epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide, and polyetherimide.

[0015] In one embodiment, the membrane electrode further includes an anode enhancement layer and / or a cathode enhancement layer, the anode enhancement layer being disposed between the anode catalytic layer and the anode gas diffusion layer, and the cathode enhancement layer being disposed between the cathode catalytic layer and the cathode gas diffusion layer.

[0016] Another object of the present invention is to provide a method for preparing a membrane electrode assembly for a fuel cell, the scheme of which is as follows:

[0017] A method for preparing a membrane electrode assembly (MEA) for a fuel cell includes the following steps:

[0018] Prepare or provide a CCM structure, the CCM structure comprising a proton exchange membrane and an anode catalyst layer and a cathode catalyst layer respectively formed on both sides of the proton exchange membrane;

[0019] An anode sealing layer is attached to the edge of the anode catalyst layer, and a cathode sealing layer is attached to the edge of the cathode catalyst layer. The anode sealing layer and the cathode sealing layer are then attached together to encapsulate the edge of the CCM structure. The edge of the anode sealing layer on the anode catalyst layer is offset from the edge of the cathode sealing layer on the cathode catalyst layer.

[0020] In one embodiment, the anode sealing layer includes a first substrate and a first adhesive layer formed on the first substrate, and the cathode sealing layer includes a second substrate and a second adhesive layer formed on the second substrate;

[0021] When the anode sealing layer and the cathode sealing layer are bonded together, the first adhesive layer is partially spilled onto the anode catalyst layer, and / or the second adhesive layer is partially spilled onto the cathode catalyst layer.

[0022] In one embodiment, the anode sealing layer and the cathode sealing layer are bonded together by hot pressing.

[0023] By controlling the thickness of the first adhesive layer, the thickness of the second adhesive layer, and the temperature, pressure, and time of the hot pressing treatment, the thickness and width of the portion of the first adhesive layer that overflows onto the anode catalyst layer and the thickness and width of the portion of the second adhesive layer that overflows onto the cathode catalyst layer are controlled.

[0024] In one embodiment, the portion of the first adhesive layer that overflows onto the anode catalyst layer has a thickness of 2-5 μm and a width of 0.3-0.6 mm.

[0025] In one embodiment, the portion of the second adhesive layer that overflows onto the cathode catalyst layer has a thickness of 2-5 μm and a width of 0.3-0.6 mm.

[0026] In one embodiment, the preparation method further includes the following steps:

[0027] An anode gas diffusion layer covers the anode catalyst layer and the anode sealing layer; and / or

[0028] An anode gas diffusion layer is covered on the cathode catalyst layer and the cathode sealing layer.

[0029] Another object of the present invention is to provide a fuel cell, the solution of which is as follows:

[0030] A fuel cell having a membrane electrode as described in any of the above embodiments or a membrane electrode prepared by the preparation method described in any of the above embodiments.

[0031] Compared with traditional methods, the above-mentioned membrane electrode and its preparation method, as well as the fuel cell, have the following advantages:

[0032] The aforementioned membrane electrode and its preparation method encapsulate the edges of the CCM structure using an anode sealing layer and a cathode sealing layer. Furthermore, the edges of the anode sealing layer on the anode catalyst layer are offset from the edges of the cathode sealing layer on the cathode catalyst layer. This reduces the shear force exerted on the proton exchange membrane by the anode and cathode sealing layers, effectively mitigating the decline in the mechanical properties of the proton exchange membrane under high and low humidity cycling conditions. Moreover, because the edges of the anode and cathode sealing layers are offset, and the asymmetry of the anode and cathode catalyst layers prevents chemical reactions in the interface cavity, creating an inert region. This effectively solves the problem of chemical degradation of the catalyst and proton exchange membrane caused by free radicals, thereby improving the lifespan of the membrane electrode.

[0033] Experimental results show that the initial power density of the membrane electrode prepared by this invention is 2–2.1 A / cm². 2 @0.65V, after 5000 cycles of carrier durability testing, 1.5A / cm 2 The voltage decay is only 22–25 mV, and the ECSA decay is only 37.5%–38.2%; after 30,000 cycles of catalyst durability testing, the voltage drop is 0.8 A / cm. 2 The voltage decay is 17-22mV, and the ECSA decay is 28.7%-33%, thus exhibiting good battery performance and durability, significantly improving the service life of automotive proton exchange membrane fuel cells, and meeting the power and durability requirements of commercial vehicles.

[0034] The above-described fuel cell has a membrane electrode as described in any of the above embodiments or a membrane electrode prepared by the preparation method described in any of the above embodiments, and thus can obtain corresponding beneficial effects. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of a membrane electrode according to one embodiment;

[0036] Figure 2 This is a schematic diagram showing the region division of the membrane electrode in the platinum loading detection test in Examples 1-3.

[0037] Explanation of reference numerals in the attached figures:

[0038] 100. Membrane electrode; 110. Proton exchange membrane; 121. Anode catalyst layer; 122. Cathode catalyst layer; 131. Anode sealing layer; 132. Cathode sealing layer; 141. First sealant; 142. Second sealant; 151. Anode gas diffusion layer; 152. Cathode gas diffusion layer; 161. Anode reinforcement layer; 162. Cathode reinforcement layer. Detailed Implementation

[0039] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0040] It should be noted that when a component is said to be "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0041] In the description of this invention, it should be understood that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0043] This invention provides a membrane electrode assembly for a fuel cell.

[0044] Please refer to Figure 1As shown, a membrane electrode assembly 100 of a fuel cell in one embodiment includes a CCM structure, an anode sealing layer 131, and a cathode sealing layer 132. The CCM structure includes a proton exchange membrane 110, an anode catalyst layer 121, and a cathode catalyst layer 122. The anode catalyst layer 121 and the cathode catalyst layer 122 are respectively disposed on both sides of the proton exchange membrane 110. The anode sealing layer 131 covers the edge of the anode catalyst layer 121, and the cathode sealing layer 132 covers the edge of the cathode catalyst layer 122. The anode sealing layer 131 and the cathode sealing layer 132 are adhered to each other to encapsulate the edge of the CCM structure. Specifically, the edge of the anode sealing layer 131 on the anode catalyst layer 121 is offset from the edge of the cathode sealing layer 132 on the cathode catalyst layer 122.

[0045] The membrane electrode assembly 100 of the aforementioned fuel cell encapsulates the edges of the CCM structure through the cooperation of the anode sealing layer 131 and the cathode sealing layer 132. Furthermore, the edge of the anode sealing layer 131 on the anode catalyst layer 121 is offset from the edge of the cathode sealing layer 132 on the cathode catalyst layer 122. This reduces the shear force exerted by the anode and cathode sealing layers 131 and 132 on the proton exchange membrane 110, effectively mitigating the decline in the mechanical properties of the proton exchange membrane 110 under high and low humidity cycling conditions. Moreover, because the edges of the anode sealing layer 131 and the cathode sealing layer 132 are offset, and the asymmetry between the anode and cathode catalyst layers 121 and 122 prevents chemical reactions in the interface cavity, creating an inert region. This effectively solves the problem of chemical degradation of the catalyst and proton exchange membrane caused by free radicals, thereby improving the lifespan of the membrane electrode assembly 100.

[0046] Experimental results show that the initial power density of the membrane electrode prepared by this invention is 2–2.1 A / cm². 2 @0.65V, after 5000 cycles of carrier durability testing, 1.5A / cm 2 The voltage decay is only 22–25 mV, and the ECSA decay is only 37.5%–38.2%; after 30,000 cycles of catalyst durability testing, the voltage drop is 0.8 A / cm. 2 The voltage decay is 17-22mV, and the ECSA decay is 28.7%-33%, thus exhibiting good battery performance and durability, significantly improving the service life of automotive proton exchange membrane fuel cells, and meeting the power and durability requirements of commercial vehicles.

[0047] In one example, the proton exchange membrane 110 is an EPTFE-enhanced composite sulfonic acid membrane.

[0048] In one example, the thickness of the proton exchange membrane 110 is 8 μm to 15 μm, specifically, it can be 10 μm, 11 μm, 13 μm, 14 μm, etc.

[0049] In one example, the anode catalyst layer 121 includes a catalyst, an ionomer, and a solvent.

[0050] Furthermore, the platinum loading of the anode catalyst layer 121 is 0.05–0.1 mg / cm³. 2 For example, 0.06 g / cm³ 2 0.07 mg / cm 2 0.08 mg / cm 2 0.09 mg / cm 2 wait.

[0051] The solid content of the anode catalyst layer 121 is 1.8% to 2.5%, specifically 1.9%, 2%, 2.2%, 2.4%, etc.

[0052] The catalyst in the anode catalyst layer 121 is a carbon-supported platinum catalyst, such as one or more of Pt / C, Pt-Co / C, and Pt-Ni / C. The mass fraction of Pt is 20% to 60%, specifically, for example, 25%, 30%, 40%, 50%, etc.

[0053] The solvent is one or more of water, isopropanol, n-propanol, ethanol, and ethylene glycol. In one example, the solvent is water, isopropanol, n-propanol, ethanol, and ethylene glycol in a mass ratio of 0.1–0.3:0–1:0–1:0–1:0–1. The EW value of the ionomer is 710–800 g / mol, specifically, for example, 720 g / mol, 740 g / mol, 760 g / mol, 780 g / mol, etc. The mass ratio of the ionomer to the catalyst carbon support is 0.75–1.0, specifically, for example, 0.8, 0.85, 0.9, 0.95, 1.0, etc. The solid content is 1.0%–1.5%, specifically, for example, 1.1%, 1.2%, 1.3%, 1.4%, etc.

[0054] In one example, the cathode catalyst layer 122 includes a catalyst, an ionomer, and a solvent.

[0055] Furthermore, the platinum loading of the cathode catalyst layer 122 is 0.2–0.35 mg / cm³. 2 For example, 0.2 g / cm³ 2 0.25 mg / cm 2 0.3 mg / cm 2 0.35 mg / cm 2 wait.

[0056] The solid content of the cathode catalyst layer 122 is 1.8% to 2.5%, specifically 1.9%, 2%, 2.2%, 2.4%, etc.

[0057] The catalyst in the cathode catalyst layer 122 is a carbon-supported platinum catalyst, such as one or more of Pt / C, Pt-Co / C, and Pt-Ni / C. The mass fraction of Pt is 40% to 60%, specifically, for example, 45%, 50%, 55%, 60%, etc.

[0058] The solvent is one or more of water, isopropanol, n-propanol, ethanol, and ethylene glycol. In one example, the solvent is water, isopropanol, n-propanol, ethanol, and ethylene glycol in a mass ratio of 0.1–0.3:0–1:0–1:0–1:0–1. The EW value of the ionomer is 725–900 g / mol, specifically, for example, 730 g / mol, 750 g / mol, 780 g / mol, 820 g / mol, etc. The mass ratio of the ionomer to the catalyst carbon support is 0.75–1.0, specifically, for example, 0.8, 0.85, 0.9, 0.95, 1.0, etc.; the solid content is 1.3%–2.0%, specifically, for example, 1.4%, 1.6%, 1.8%, 2.0%, etc.

[0059] The anode sealing layer 131 includes a first substrate and a first adhesive layer disposed on the first substrate. The material of the first substrate may be, for example, PEN, PI, etc. The material of the first adhesive layer may be, for example, silicone.

[0060] The cathode sealing layer 132 includes a second substrate and a second adhesive layer disposed on the second substrate. The material of the second substrate may be, for example, PEN, PI, etc. The material of the second adhesive layer may be, for example, silicone.

[0061] In one example, the anode sealing layer 131 covers the edge of the anode catalyst layer 121 with a width of 2 mm to 3 mm.

[0062] In one example, the width of the cathode sealing layer 132 covering the edge of the cathode catalyst layer 122 is 2.8 mm to 4.6 mm.

[0063] In one example, the distance between the edge of the anode sealing layer 131 on the anode catalyst layer 121 and the edge of the cathode sealing layer 132 on the cathode catalyst layer 122 is 0.8 mm to 1.6 mm, specifically, it can be 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 1.6 mm, etc.

[0064] In one example, the area of ​​the anode catalyst layer 121 not covered by the anode sealing layer 131 is larger than the area of ​​the cathode catalyst layer 122 not covered by the cathode sealing layer 132.

[0065] like Figure 1As shown, in one example, the membrane electrode 100 further includes an anode gas diffusion layer 151, which covers the anode catalyst layer 121 and the anode sealing layer 131.

[0066] Furthermore, a first sealant 141 is provided at the junction of the anode gas diffusion layer 151, the anode catalyst layer 121, and the anode sealing layer 131. The first sealant 141 may be, for example, at least one of silicone, epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide, and polyetherimide.

[0067] In the above example, by setting a first sealant 141 at the junction of the anode gas diffusion layer 151, the anode catalyst layer 121 and the anode sealing layer 131, the cavity at the junction is eliminated. In this way, the mass transfer of the entire anode active region of the membrane electrode 100 is uniform, no local performance difference is generated, and a uniform and stable current output is obtained, thereby significantly improving the life of the membrane electrode 100.

[0068] like Figure 1 As shown, in one example, the membrane electrode 100 further includes a cathode gas diffusion layer 152, which covers the cathode catalyst layer 122 and the cathode sealing layer 132. The second sealant 142 may be, for example, at least one of silicone, polyacrylic acid, polyisobutylene, epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide, and polyetherimide.

[0069] Furthermore, a second sealant 142 is provided at the junction of the cathode gas diffusion layer 152, the cathode catalyst layer 122, and the cathode sealing layer 132.

[0070] In the above example, by providing a second sealant 142 at the junction of the cathode gas diffusion layer 152, the cathode catalyst layer 122 and the cathode sealing layer 132, the cavity at the junction is eliminated. In this way, the mass transfer of the entire cathode active region of the membrane electrode 100 is uniform, no local performance difference is generated, and a uniform and stable current output is obtained, thereby significantly improving the life of the membrane electrode 100.

[0071] like Figure 1 As shown, in one example, the membrane electrode 100 further includes an anode reinforcement layer 161 disposed between the anode catalyst layer 121 and the anode gas diffusion layer 151. The anode reinforcement layer 161 comprises a reinforcing material, additives, and a solvent.

[0072] The reinforcing material is, for example, one or more of cerium oxide, yttrium oxide, and zirconium oxide. The additive is, for example, one or more of conductive carbon black, carbon nanotubes, and graphene. The solvent is one or more of water, isopropanol, n-propanol, and ethanol. In one example, the solvent is water, isopropanol, n-propanol, and ethanol in a mass ratio of 0.1–0.3:0–1:0–1:0–1.

[0073] In one example, the solid content of the anode reinforcement layer 161 is 1.0% to 1.5%, specifically, for example, 1.0%, 1.2%, 1.3%, 1.4%, etc.

[0074] In one example, the thickness of the anode reinforcement layer 161 is 1 μm to 3 μm, specifically, it can be 1 μm, 1.5 μm, 2 μm, 2.5 μm, etc.

[0075] like Figure 1 As shown, in one example, the membrane electrode 100 further includes a cathode reinforcement layer 162 disposed between the cathode catalytic layer 122 and the cathode gas diffusion layer 152. The cathode reinforcement layer 162 comprises a reinforcing material, additives, and a solvent.

[0076] The reinforcing material is, for example, one or more of cerium oxide, yttrium oxide, and zirconium oxide. The additive is, for example, one or more of conductive carbon black, carbon nanotubes, and graphene. The solvent is one or more of water, isopropanol, n-propanol, and ethanol. In one example, the solvent is water, isopropanol, n-propanol, and ethanol in a mass ratio of 0.1–0.3:0–1:0–1:0–1.

[0077] In one example, the solid content of the cathode reinforcement layer 162 is 1.0% to 1.5%, specifically, for example, 1.0%, 1.2%, 1.3%, 1.4%, etc.

[0078] In one example, the thickness of the cathode reinforcement layer 162 is 1 μm to 3 μm, specifically, it can be 1 μm, 1.5 μm, 2 μm, 2.5 μm, etc.

[0079] Figure 1 The membrane electrode 100 shown in the specific example includes a proton exchange membrane 110, an anode catalyst layer 121, a cathode catalyst layer 122, an anode sealing layer 131, a cathode sealing layer 132, an anode enhancement layer 161, a cathode enhancement layer 162, an anode gas diffusion layer 151, and a cathode gas diffusion layer 152.

[0080] The anode catalyst layer 121 and the cathode catalyst layer 122 are respectively disposed on both sides of the proton exchange membrane 110.

[0081] The anode sealing layer 131 covers the edge of the anode catalyst layer 121, and the cathode sealing layer 132 covers the edge of the cathode catalyst layer 122. The anode sealing layer 131 and the cathode sealing layer 132 are adhered to each other to fit the edge of the CCM structure. The edge of the anode sealing layer 131 on the anode catalyst layer 121 is offset from the edge of the cathode sealing layer 132 on the cathode catalyst layer 122.

[0082] An anode gas diffusion layer 151 covers the anode catalyst layer 121 and the anode sealing layer 131. A first sealant 141 is provided at the junction of the anode gas diffusion layer 151, the anode catalyst layer 121, and the anode sealing layer 131. A cathode gas diffusion layer 152 covers the cathode catalyst layer 122 and the cathode sealing layer 132. A second sealant 142 is provided at the junction of the cathode gas diffusion layer 152, the cathode catalyst layer 122, and the cathode sealing layer 132.

[0083] An anode reinforcement layer 161 is disposed between an anode catalyst layer 121 and an anode gas diffusion layer 151. A cathode reinforcement layer 162 is disposed between a cathode catalyst layer 122 and a cathode gas diffusion layer 152.

[0084] The membrane electrode assembly 100 of the aforementioned fuel cell encapsulates the edges of the CCM structure through the cooperation of the anode sealing layer 131 and the cathode sealing layer 132. Furthermore, the edge of the anode sealing layer 131 on the anode catalyst layer 121 is offset from the edge of the cathode sealing layer 132 on the cathode catalyst layer 122. This reduces the shear force exerted by the anode and cathode sealing layers 131 and 132 on the proton exchange membrane 110, effectively mitigating the decline in the mechanical properties of the proton exchange membrane 110 under high and low humidity cycling conditions. Moreover, because the edges of the anode sealing layer 131 and the cathode sealing layer 132 are offset, and the asymmetry between the anode and cathode catalyst layers 121 and 122 prevents chemical reactions in the interface cavity, creating an inert region that effectively solves the problem of chemical degradation of the catalyst and proton exchange membrane caused by free radicals.

[0085] On the other hand, by setting a sealant at the junction of the gas diffusion layer, the catalyst layer and the sealing layer, the cavity at the junction is eliminated. In this way, the mass transfer of the anodic and cathode active regions of the entire membrane electrode 100 is uniform, no local performance difference is generated, and a uniform and stable current output is obtained, thereby significantly improving the life of the membrane electrode 100.

[0086] Furthermore, the present invention also provides a method for preparing a membrane electrode 100 for a fuel cell.

[0087] A method for preparing a membrane electrode 100 according to an embodiment includes the following steps:

[0088] Prepare or provide a CCM structure, the CCM structure including a proton exchange membrane 110 and an anode catalyst layer 121 and a cathode catalyst layer 122 respectively formed on both sides of the proton exchange membrane 110;

[0089] An anode sealing layer 131 is attached to the edge of the anode catalyst layer 121, and a cathode sealing layer 132 is attached to the edge of the cathode catalyst layer 122. The anode sealing layer 131 and the cathode sealing layer 132 are then attached to fit the edge of the encapsulated CCM structure. The edge of the anode sealing layer 131 on the anode catalyst layer 121 is offset from the edge of the cathode sealing layer 132 on the cathode catalyst layer 122.

[0090] The anode sealing layer 131 includes a first substrate and a first adhesive layer formed on the first substrate. The cathode sealing layer 132 includes a second substrate and a second adhesive layer formed on the second substrate.

[0091] In one example, during the bonding of the anode sealing layer 131 and the cathode sealing layer 132, a portion of the first adhesive layer overflows onto the anode catalyst layer 121. The overflowed adhesive, when subsequently covering the anode gas diffusion layer 151, eliminates cavities at the interface, ensuring uniform mass transfer across the entire anode active region of the membrane electrode 100, preventing localized performance differences, and achieving a uniform and stable current output. This significantly improves the lifetime of the membrane electrode 100.

[0092] In one example, the portion of the first adhesive layer that overflows onto the anode catalyst layer 121 has a thickness of 2-5 μm and a width of 0.3-0.6 mm.

[0093] Similarly, when the anode sealing layer 131 and the cathode sealing layer 132 are bonded together, the second adhesive layer may partially overflow onto the cathode catalyst layer 122.

[0094] In one example, the portion of the second adhesive layer that overflows onto the cathode catalyst layer 122 has a thickness of 2-5 μm and a width of 0.3-0.6 mm.

[0095] In one example, the anode sealing layer 131 and the cathode sealing layer 132 are bonded together by hot pressing.

[0096] Furthermore, by controlling the thickness of the first adhesive layer, the thickness of the second adhesive layer, and the temperature, pressure, and time of the hot pressing treatment, the thickness and width of the portion of the first adhesive layer overflowing onto the anode catalyst layer 121 and the thickness and width of the portion of the second adhesive layer overflowing onto the cathode catalyst layer 122 are controlled.

[0097] In one example, the thickness of the first adhesive layer and the thickness of the second adhesive layer are 2-5 μm.

[0098] In one example, the hot pressing treatment was performed at a temperature of 105℃ to 120℃, a pressure of 0.8MPa to 1MPa, and a time of 30s to 60s.

[0099] In one example, the fabrication method of the membrane electrode 100 further includes the following steps:

[0100] An anode gas diffusion layer 151 is covered on the anode catalyst layer 121 and the anode sealing layer 131.

[0101] Furthermore, in one example, after covering one side of the anode gas diffusion layer 151 with the anode reinforcement layer 161, the anode reinforcement layer 161 is then covered on the anode catalyst layer 121 and the anode sealing layer 131.

[0102] In one example, the fabrication method of the membrane electrode 100 further includes the following steps:

[0103] An anode gas diffusion layer 151 is covered on the cathode catalyst layer 122 and the cathode sealing layer 132.

[0104] Furthermore, in one example, after first covering one side of the cathode gas diffusion layer 152 with the cathode reinforcement layer 162, the cathode reinforcement layer 162 is then covered on the cathode catalyst layer 122 and the cathode sealing layer 132.

[0105] Furthermore, the present invention also provides a fuel cell.

[0106] One embodiment of the fuel cell has a membrane electrode 100 of any of the above examples or a membrane electrode 100 prepared by any of the above examples.

[0107] Therefore, the fuel cell can have all the features and advantages of the membrane electrode 100 described above.

[0108] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to the specific embodiments described below.

[0109] Example 1

[0110] The method for fabricating the membrane electrode assembly of the fuel cell in this embodiment is as follows:

[0111] Step 1: Slurry preparation.

[0112] Preparation of the anode catalyst slurry: 0.8 g of 40% Pt / C catalyst, 20 g of water, 4.6 g of ionomer with an EW value of 710 g / mol and a mass fraction of 5%, and 42 g of n-propanol were mixed. The mixture was dispersed in a ball mill for 4 h, and then 0.1 g of 86% IrO2 was added to obtain the anode catalyst slurry.

[0113] Preparation of cathode catalyst slurry: 0.8g of Pt-Co / C catalyst with a mass fraction of 52%, 20g of water, 4.8g of ionomer with an EW value of 725g / mol and a mass fraction of 5%, and 56g of n-propanol were mixed and dispersed in a ball mill for 5h to obtain cathode catalyst slurry.

[0114] Preparation of anode reinforcement layer slurry: 0.2g cerium oxide, 0.2g graphene and 8g water were ultrasonically stirred for 30min, then 20g n-propanol was added and mixed, and the mixture was further dispersed in an ultrasonic device for 2h to obtain anode reinforcement layer slurry.

[0115] Preparation of cathode reinforcement layer slurry: 0.1g zirconium oxide, 0.2g conductive carbon black and 10g water were ultrasonically stirred for 30min, then 18g n-propanol was added and mixed. The mixture was then dispersed in an ultrasonic device for 2h to obtain cathode reinforcement layer slurry.

[0116] Step 2: Using ultrasonic spraying, the cathode catalyst slurry and the anode catalyst slurry are respectively applied to both sides of the 12μm thick Gore proton exchange membrane. The cathode catalyst layer has a thickness of 13μm and a platinum loading of 0.3mg / cm³. 2 The thickness of the anode catalyst layer is 5 μm, and the platinum loading is 0.1 mg / cm³. 2 .

[0117] Step 3: Using ultrasonic spraying, the cathode reinforcement layer slurry is applied onto a 168 μm thick cathode gas diffusion layer (Toray 055) to obtain the first composite layer. The anode reinforcement layer slurry is then applied onto a 168 μm thick anode gas diffusion layer (Toray 055) to obtain the second composite layer. The reinforcement layer thickness is 2 μm, and the cerium loading is 30 μg / cm³. 2 .

[0118] Step 4: Seal the anode sealing layer with a total thickness of 45μm (including a 15μm silicone adhesive layer) and a PEN substrate onto the anode catalyst layer. The overlap between the anode sealing layer and the anode catalyst layer is 2mm.

[0119] A cathode sealing layer with a total thickness of 45 μm (including a 15 μm silicone adhesive layer) and a PEN substrate is further bonded to one side of the aforementioned cathode catalyst layer and bonded to the anode sealing layer. The overlap between the cathode sealing layer and the cathode catalyst layer is 3.6 mm. This yields a five-in-one membrane electrode.

[0120] Step 5: Place the above-mentioned five-in-one membrane electrode in a hot pressing mold and hot press it at a temperature of 105℃, a pressure of 0.8MPa, and a time of 60s. The width of the adhesive layer overflowing onto the cathode catalyst layer and the anode catalyst layer is 0.5mm and the thickness is 5μm.

[0121] Step 6: Apply UV adhesive to the edges of the first and second composite layers, 0.8 mm from the outer edge of the gas diffusion layer, with a width of 0.6 mm. After vacuum high-temperature treatment at 80°C, place them on both sides of the five-in-one membrane electrode and press them at 0.1 MPa for 30 seconds to obtain the membrane electrode.

[0122] The membrane electrode prepared in Example 1 was subjected to single-cell testing, including a 5000-cycle support durability test and a 30000-cycle catalyst durability test. The test conditions for the 5000-cycle support durability test are shown in Table 1, and the test results are shown in Table 2. The test conditions for the 30000-cycle catalyst durability test are shown in Table 3, and the test results are shown in Table 4.

[0123] The test results show that the membrane electrode prepared in Example 1 exhibits excellent performance and durability. Specifically, the initial power density of the membrane electrode prepared in Example 1 is 2 A / cm³. 2 @0.65V, after 5000 cycles of carrier durability testing, 1.5A / cm 2 The voltage decay is only 25mV and the ECSA decay is only 38%; after 30,000 cycles of catalyst durability testing, the voltage drop is 0.8A / cm. 2 The voltage decay is 22mV and the ECSA decay is 33%, thus demonstrating good battery performance and durability, significantly improving the service life of automotive proton exchange membrane fuel cells, and meeting the power and durability requirements of commercial vehicles.

[0124] The tested membrane electrode was divided into regions, as follows: Figure 2 As shown in Table 5, the platinum loading of the tested membrane electrode was measured. XRF was used to scan the platinum loading in different regions of the membrane electrode, and the test results are shown in Table 1. As can be seen from the results in Table 5, the test results have high precision. It can be seen that the platinum loading at the junctions (regions 1, 2, 3, 4, 6, 7, 9, 12, 13, 14, 15) shows good platinum distribution consistency with the central region (regions 5, 8, 11). This indicates that Example 1 can improve battery consistency and durability.

[0125] Table 1. Conditions for 5000-cycle carrier durability test

[0126]

[0127] Table 2 Results of 5000-cycle carrier durability test

[0128]

[0129] Table 3. Catalyst durability test conditions for 30,000 cycles

[0130]

[0131]

[0132] Table 4. Results of 30,000 catalyst durability tests

[0133]

[0134] Table 5 Platinum loading in the region of the membrane electrode

[0135]

[0136] Example 2

[0137] The method for fabricating the membrane electrode assembly of the fuel cell in this embodiment is as follows:

[0138] Step 1: Slurry preparation.

[0139] Preparation of the anode catalyst slurry: 0.8 g of 20% Pt / C catalyst, 23 g of water, 9 g of ionomer with an EW value of 800 g / mol and a mass fraction of 5%, 8 g of n-propanol, and 30 g of ethanol were mixed. The mixture was sheared at 10,000 rpm for 2 h in an ice bath at 10 °C, and then 0.08 g of 86% IrO2 was added to obtain the anode catalyst slurry.

[0140] Preparation of cathode catalyst slurry: 0.8 g of 60% Pt / C catalyst, 25 g of water, 5% ionomer with an EW value of 900 g / mol, 40 g of n-propanol and 5 g of ethanol were mixed and ultrasonically dispersed in an ice bath for 2 h to obtain cathode catalyst slurry.

[0141] Preparation of anodic reinforcement layer slurry: 0.15g zirconium oxide, 0.2g carbon nanotubes and 6g water were ultrasonically stirred for 30min, then 25g n-propanol was added and mixed. The mixture was dispersed in a ball mill for 2h to obtain anodic reinforcement layer slurry.

[0142] Preparation of cathode reinforcement layer slurry: 0.22g zirconium oxide, 0.15g graphene and 6g water were ultrasonically stirred for 30min, then 25g isopropanol was added and mixed. The mixture was dispersed in a ball mill for 2h to obtain cathode reinforcement layer slurry.

[0143] Step 2: Using ultrasonic spraying, the cathode catalyst slurry and the anode catalyst slurry are respectively coated onto both sides of a 15μm thick Gore proton exchange membrane. The cathode catalyst layer has a thickness of 12μm and a platinum loading of 0.28 mg / cm³. 2 The thickness of the anode catalyst layer is 5 μm, and the platinum loading is 0.08 mg / cm³. 2 .

[0144] Step 3: Using ultrasonic spraying, the cathode reinforcement layer slurry is applied onto a 168 μm thick cathode gas diffusion layer (Frederick H14CX483) to obtain the first composite layer. The anode reinforcement layer slurry is then applied onto a 168 μm thick anode gas diffusion layer (Frederick H14CX483) to obtain the second composite layer. The reinforcement layer thickness is 4 μm, and the zirconium loading is 26 μg / cm³. 2 .

[0145] Step 4: Seal the anode sealing layer with a total thickness of 37μm (including a 13μm silicone adhesive layer) and a PI substrate onto the anode catalyst layer. The overlap between the anode sealing layer and the anode catalyst layer is 2.5mm.

[0146] A cathode sealing layer with a total thickness of 37 μm (including a 13 μm silicone adhesive layer) and a PI substrate is further bonded to one side of the aforementioned cathode catalyst layer and bonded to the anode sealing layer. The overlap between the cathode sealing layer and the cathode catalyst layer is 3.3 mm. This yields a five-in-one membrane electrode.

[0147] Step 5: Place the above five-in-one membrane electrode in a hot press mold and hot press it at a temperature of 120°C, a pressure of 1.0 MPa, and a time of 30 s. The width of the adhesive layer overflowing onto the cathode catalyst layer and the anode catalyst layer is 0.2 mm and the thickness is 4 μm.

[0148] Step 6: Apply UV adhesive to the edges of the first and second composite layers, 0.6 mm from the outer edge of the gas diffusion layer, with a width of 0.8 mm. After vacuum high-temperature treatment at 80°C, place them on both sides of the five-in-one membrane electrode and press them at 0.3 MPa for 45 s to obtain the membrane electrode.

[0149] The membrane electrode prepared in Example 1 was subjected to single-cell testing, including a 5000-cycle support durability test and a 30000-cycle catalyst durability test. The test conditions for the 5000-cycle support durability test are shown in Table 6, and the test results are shown in Table 7. The test conditions for the 30000-cycle catalyst durability test are shown in Table 8, and the test results are shown in Table 9.

[0150] The test results show that the membrane electrode prepared in Example 2 exhibits excellent performance and durability. Specifically, the initial power density of the membrane electrode prepared in Example 2 is 2.05 A / cm². 2 @0.65V, after 5000 cycles of carrier durability testing, 1.5A / cm 2 The voltage decay is only 25mV and the ECSA decay is only 37.5%; after 30,000 cycles of catalyst durability testing, the voltage drop is 0.8A / cm. 2The voltage decay was 18mV and the ECSA decay was 28.7%, thus demonstrating good battery performance and durability, significantly improving the service life of automotive proton exchange membrane fuel cells and meeting the power and durability requirements of commercial vehicles.

[0151] The tested membrane electrode was divided into regions, as follows: Figure 2 As shown in Table 10, the platinum loading of the tested membrane electrode was measured using XRF to scan the platinum loading in different regions. The results are shown in Table 10. As can be seen from the results in Table 10, the test results are highly precise. It can be seen that the platinum loading at the junctions (regions 1, 2, 3, 4, 6, 7, 9, 12, 13, 14, 15) shows good platinum distribution consistency with the central region (regions 5, 8, 11). This indicates that Example 1 can improve battery consistency and durability.

[0152] Table 6. Conditions for 5000-cycle carrier durability test

[0153]

[0154]

[0155] Table 7 Results of 5000-cycle carrier durability test

[0156]

[0157] Table 8. Catalyst durability test conditions for 30,000 cycles

[0158]

[0159] Table 9 Results of 30,000 Catalyst Durability Tests

[0160]

[0161]

[0162] Table 10 Platinum loading in the region of the membrane electrode

[0163]

[0164] Example 3

[0165] The method for fabricating the membrane electrode assembly of the fuel cell in this embodiment is as follows:

[0166] Step 1: Slurry preparation.

[0167] Preparation of the anode catalyst slurry: 0.8 g of 40% Pt-Ni / C catalyst, 20 g of water, 8 g of ionomer with an EW value of 710 g / mol and a mass fraction of 5%, and 42 g of ethanol were mixed. The mixture was sheared at 10,000 rpm for 3 h in an ice bath at 15 °C, and then 0.06 g of 86% IrO2 was added to obtain the anode catalyst slurry.

[0168] Preparation of cathode catalyst slurry: 0.8g of 60% Pt / C catalyst, 28g of water, 7.8g of ionomer with an EW value of 780g / mol and a mass fraction of 5%, 13g of ethanol and 22g of n-propanol were mixed and ultrasonically dispersed in an ice bath for 1.5h to obtain cathode catalyst slurry.

[0169] Preparation of anode reinforcement layer slurry: 0.15g yttrium oxide, 0.2g conductive carbon black and 6g water were ultrasonically stirred for 30min, then 25g n-propanol was added and mixed. The mixture was then subjected to high-speed shearing at 10000 rpm for 2h to obtain anode reinforcement layer slurry.

[0170] Preparation of cathode reinforcement layer slurry: 0.15g yttrium oxide, 0.18g carbon nanotubes and 6g water were ultrasonically stirred for 30min, then 25g isopropanol was added and mixed. The mixture was then sheared at 10000 rpm for 2h to obtain cathode reinforcement layer slurry.

[0171] Step 2: Using ultrasonic spraying, the cathode catalyst slurry and the anode catalyst slurry are respectively applied to both sides of the 8μm thick Gore proton exchange membrane. The cathode catalyst layer has a thickness of 13μm and a platinum loading of 0.20 mg / cm³. 2 The thickness of the anode catalyst layer is 4 μm, and the platinum loading is 0.08 mg / cm³. 2 .

[0172] Step 3: Using ultrasonic spraying, the cathode reinforcement layer slurry is applied onto a 184 μm thick cathode gas diffusion layer (Frederick H14CX483) to obtain the first composite layer. The anode reinforcement layer slurry is then applied onto a 184 μm thick anode gas diffusion layer (Frederick H14CX483) to obtain the second composite layer. The reinforcement layer thickness is 2 μm, and the yttrium loading is 26 μg / cm³. 2 .

[0173] Step 4: Seal the anode sealing layer with a total thickness of 37μm (including a 13μm silicone adhesive layer) and a PI substrate onto the anode catalyst layer. The overlap between the anode sealing layer and the anode catalyst layer is 2.5mm.

[0174] A cathode sealing layer with a total thickness of 37 μm (including a 13 μm silicone adhesive layer) and a PI substrate is further bonded to one side of the aforementioned cathode catalyst layer and bonded to the anode sealing layer. The overlap between the cathode sealing layer and the cathode catalyst layer is 3.5 mm. This yields a five-in-one membrane electrode.

[0175] Step 5: Place the above five-in-one membrane electrode in a hot press mold and hot press it at a temperature of 108°C, a pressure of 1.0 MPa, and a time of 30 s. The width of the adhesive layer overflowing onto the cathode catalyst layer and the anode catalyst layer is 0.3 mm and the thickness is 5 μm.

[0176] Step 6: Apply UV adhesive to the edges of the first and second composite layers, 0.6 mm from the outer edge of the gas diffusion layer, with a width of 0.6 mm. After vacuum high-temperature treatment at 80°C, place them on both sides of the five-in-one membrane electrode and press them at 0.5 MPa for 30 seconds to obtain the membrane electrode.

[0177] The membrane electrode prepared in Example 1 was subjected to single-cell testing, including a 5000-cycle support durability test and a 30000-cycle catalyst durability test. The test conditions for the 5000-cycle support durability test are shown in Table 11, and the test results are shown in Table 12. The test conditions for the 30000-cycle catalyst durability test are shown in Table 13, and the test results are shown in Table 14.

[0178] The test results show that the membrane electrode prepared in Example 3 exhibits excellent performance and durability. Specifically, the initial power density of the membrane electrode prepared in Example 3 is 2.1 A / cm³. 2 @0.65V, after 5000 cycles of carrier durability testing, 1.5A / cm 2 The voltage decay is only 22mV and the ECSA decay is only 38.2%; after 30,000 cycles of catalyst durability testing, the voltage drop is 0.8A / cm. 2 The voltage decay was 17mV and the ECSA decay was 29.3%, thus demonstrating good battery performance and durability, significantly improving the service life of automotive proton exchange membrane fuel cells and meeting the power and durability requirements of commercial vehicles.

[0179] The tested membrane electrode was divided into regions, as follows: Figure 2 As shown in Table 15, the platinum loading of the tested membrane electrode was measured using XRF to scan the platinum loading in different regions. The results are as follows: Table 15 shows that the test results are highly precise. It can be seen that the platinum loading at the junctions (regions 1, 2, 3, 4, 6, 7, 9, 12, 13, 14, 15) exhibits good platinum distribution consistency with the central region (regions 5, 8, 11). This demonstrates that Example 1 can improve battery consistency and durability.

[0180] Table 11 Conditions for 5000 Cycles Carrier Durability Test

[0181]

[0182] Table 12 Conditions for 5000 Cycles Carrier Durability Test

[0183]

[0184]

[0185] Table 13. Catalyst durability test conditions for 30,000 cycles

[0186]

[0187] Table 14. Catalyst durability test conditions for 30,000 cycles

[0188]

[0189] Table 15 Platinum loading in the region of the membrane electrode

[0190]

[0191]

[0192] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0193] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A membrane electrode for a fuel cell, characterized by, The membrane electrode comprises a CCM structure, an anode sealing layer and a cathode sealing layer; the CCM structure comprises a proton exchange membrane and an anode catalytic layer and a cathode catalytic layer arranged on two sides of the proton exchange membrane respectively, the anode sealing layer covers the edge of the anode catalytic layer, the cathode sealing layer covers the edge of the cathode catalytic layer, and the anode sealing layer and the cathode sealing layer are attached to cooperatively encapsulate the edge of the CCM structure, the edge of the anode sealing layer on the anode catalytic layer is staggered with the edge of the cathode sealing layer on the cathode catalytic layer; the membrane electrode further comprises an anode gas diffusion layer and / or a cathode gas diffusion layer, the anode gas diffusion layer covers the anode catalytic layer and the anode sealing layer, and the cathode gas diffusion layer covers the cathode catalytic layer and the cathode sealing layer; a first sealing glue is arranged at the junction of the anode gas diffusion layer, the anode catalytic layer and the anode sealing layer, and / or a second sealing glue is arranged at the junction of the cathode gas diffusion layer, the cathode catalytic layer and the cathode sealing layer.

2. The membrane electrode of claim 1, wherein, The distance between the edge of the anode sealing layer on the anode catalytic layer and the edge of the cathode sealing layer on the cathode catalytic layer is 0.8mm-1.6mm.

3. The membrane electrode according to claim 1 or 2, characterized in that, The area of the region of the anode catalytic layer not covered by the anode sealing layer is larger than the area of the region of the cathode catalytic layer not covered by the cathode sealing layer.

4. The membrane electrode of claim 1, wherein, The width of the edge of the anode catalytic layer covered by the anode sealing layer is 2mm-3mm.

5. The membrane electrode of claim 1, wherein, The width of the edge of the cathode catalytic layer covered by the cathode sealing layer is 2.8mm-4.6mm.

6. The membrane electrode of claim 1, wherein, The first sealing glue is at least one of silicone, epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide and polyetherimide; and / or the second sealing glue is at least one of silicone, polyacrylic acid, polyisobutylene, epoxy resin, unsaturated polyester, phenolic resin, vinyl ester, polyamide, polyphenylene sulfide and polyetherimide.

7. The membrane electrode of claim 1, wherein, The membrane electrode further comprises an anode reinforcing layer and / or a cathode reinforcing layer, the anode reinforcing layer is arranged between the anode catalytic layer and the anode gas diffusion layer, and the cathode reinforcing layer is arranged between the cathode catalytic layer and the cathode gas diffusion layer.

8. A method for producing a membrane electrode of a fuel cell as claimed in any one of claims 1 to 7, characterized by, The method comprises the following steps: Preparation or provision of a CCM structure, the CCM structure comprising a proton exchange membrane and an anode catalytic layer and a cathode catalytic layer formed on two sides of the proton exchange membrane respectively; Attaching an anode sealing layer to the edge of the anode catalytic layer and a cathode sealing layer to the edge of the cathode catalytic layer, and attaching the anode sealing layer and the cathode sealing layer to cooperatively encapsulate the edge of the CCM structure, the edge of the anode sealing layer on the anode catalytic layer being staggered with the edge of the cathode sealing layer on the cathode catalytic layer; The anode sealing layer comprises a first substrate and a first glue layer formed on the first substrate, and the cathode sealing layer comprises a second substrate and a second glue layer formed on the second substrate; In the process of adhering the anode sealing layer and the cathode sealing layer, the first adhesive layer is allowed to overflow onto the anode catalytic layer, and / or the second adhesive layer is allowed to overflow onto the cathode catalytic layer.

9. The production method according to claim 8, wherein The thickness of the first adhesive layer and the thickness of the second adhesive layer are 2-5 μm.

10. The production method according to claim 9, wherein The adhering process of the anode sealing layer and the cathode sealing layer is a hot-pressing process. By controlling the thickness of the first adhesive layer, the thickness of the second adhesive layer, and the temperature, pressure and time of the hot-pressing process, the thickness and width of the part of the first adhesive layer overflowing onto the anode catalytic layer and the thickness and width of the part of the second adhesive layer overflowing onto the cathode catalytic layer are controlled.

11. The production method according to claim 10, wherein The thickness of the part of the first adhesive layer overflowing onto the anode catalytic layer is 2-5 μm, and the width is 0.3-0.6 mm; and / or The thickness of the part of the second adhesive layer overflowing onto the cathode catalytic layer is 7-12 μm, and the width is 0.1-0.25 mm.

12. The production method according to any one of claims 8 to 11, wherein The preparation method further comprises the following steps: covering an anode gas diffusion layer on the anode catalytic layer and the anode sealing layer; and / or covering a cathode gas diffusion layer on the cathode catalytic layer and the cathode sealing layer.

13. A fuel cell characterized by comprising: The membrane electrode as claimed in any one of claims 1-7 or prepared by the preparation method as claimed in any one of claims 8-12.

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