A membrane electrode gas tightness detection assembly

Abstract

The application relates to a film electrode air tightness detection assembly. The film electrode air tightness detection assembly comprises an upper laminated block, a lower laminated block, a plurality of conductive combination plates and film electrode sheets. The upper laminated block and the lower laminated block are oppositely arranged and have a pressing space therebetween. The plurality of conductive combination plates are arranged in the pressing space, each conductive combination plate comprises a detection air flow field and an air flow field arranged on both sides thereof, adjacent conductive combination plates have a clamping gap therebetween, each clamping gap is used for placing a film electrode sheet, the anode side of each film electrode sheet and the adjacent detection air flow field form a first air cavity, all the first air cavities are communicated with each other, the cathode side of each film electrode sheet and the adjacent air flow field form a second air cavity, all the second air cavities are communicated with each other, the upper laminated block is provided with a detection air inlet and a detection air outlet communicated with the first air cavity and an air inlet and an air outlet communicated with the second air cavity.

Description

Technical Field

[0001] This application relates to the field of fuel cell technology, and in particular to a membrane electrode airtightness detection component. Background Technology

[0002] Proton exchange membrane (PEM) fuel cells efficiently convert hydrogen energy into electrical energy through electrochemical reactions, offering advantages such as zero emissions, high energy density, and fast start-up speed. They are widely used in transportation, distributed power generation, and other fields. The membrane electrode assembly (MEA), as the core area of ​​the electrochemical reaction in a PEM fuel cell, directly determines the performance and safety of the stack due to its airtightness. Leakage in the MEA (i.e., gas leakage between the anode and cathode) is a critical hidden danger affecting stack operation, typically caused by pinholes in the MEA membrane or defects in the frame encapsulation. Leakage not only leads to the ineffective consumption of detection gas and oxygen, reducing the stack's power generation efficiency, but can also create a hydrogen-oxygen mixing interface inside the stack, causing localized overheating, combustion, or even explosion risks, seriously threatening the safe operation of the stack.

[0003] In existing technologies, fuel cell stack manufacturers typically conduct overall airtightness testing after the membrane electrode assembly. However, if cross-leakage is detected at this stage, it is difficult to accurately pinpoint which membrane electrode is defective, requiring disassembly of the fuel cell stack for individual inspection, resulting in significantly reduced assembly efficiency and increased costs. For individual membrane electrode testing before shipment, traditional methods often employ an anode-side pressurization and cathode-side pressure measurement mode, monitoring cathode-side pressure changes to determine cross-leakage and relying on soap membrane flow meters for flow calibration to obtain the leakage rate. This method has significant drawbacks: it can only test one membrane electrode at a time, resulting in extremely low testing efficiency, which cannot meet the needs of industrial mass production. Furthermore, the operation process is complex, requiring frequent manual equipment calibration, leading to significant human error.

[0004] Therefore, there is an urgent need for a membrane electrode airtightness testing solution that is simple in structure, highly efficient, accurate, and suitable for mass production, in order to solve the testing problems in the existing technology. Utility Model Content

[0005] Therefore, it is necessary to provide a membrane electrode airtightness detection component to address the problems of low detection efficiency and difficulty in defect localization in membrane electrode airtightness detection technology.

[0006] A membrane electrode airtightness detection component, comprising:

[0007] Upper pressing block and lower pressing block arranged opposite to the upper pressing block;

[0008] There is a pressing space between the upper pressing blocks;

[0009] Several conductive composite plates are arranged within the pressing space;

[0010] Each conductive assembly plate includes a detection airflow field and an airflow field disposed on both sides thereof;

[0011] There are clamping gaps between adjacent conductive composite plates, and each clamping gap is used to place a membrane electrode sheet;

[0012] The anode side of each membrane electrode sheet is surrounded by the adjacent detection gas flow field to form a first gas chamber, and all the first gas chambers are interconnected.

[0013] Each membrane electrode sheet has its cathode side surrounded by an adjacent airflow field to form a second air chamber, and all the second air chambers are interconnected.

[0014] The upper pressure block has a detection air inlet and a detection air outlet that communicate with the first air chamber, as well as an air inlet and an air outlet that communicate with the second air chamber.

[0015] In one embodiment, the conductive composite plate includes a first electrode plate and a second electrode plate that are connected to each other;

[0016] The airflow field is detected on the surface of the first electrode plate that is away from the second electrode plate;

[0017] The first electrode plate has a first inlet half-shell and a first outlet half-shell.

[0018] The second electrode plate has a second inlet half-shell and a second outlet half-shell.

[0019] The first inlet half-shell and the second inlet half-shell together form the detection gas inlet channel;

[0020] The second inlet half-shell and the second outlet half-shell together form the detection gas outlet channel.

[0021] One end of the detection gas inlet channel is connected to the detection gas inlet, and the other end of the detection gas inlet channel is used to connect to the first gas chamber;

[0022] One end of the detection gas outlet channel is connected to the detection gas outlet, and the other end of the detection gas outlet channel is used to connect to the first gas chamber.

[0023] In one embodiment, the airflow field is disposed on the surface of the second electrode plate opposite to the first electrode plate;

[0024] The first electrode plate has a third inlet half-shell and a third outlet half-shell.

[0025] The second electrode plate has a fourth inlet half-shell and a fourth outlet half-shell.

[0026] The third and fourth inlet half-shells together form an air inlet channel;

[0027] The third and fourth outlet half-shells together form an air outlet channel.

[0028] One end of the air inlet channel is connected to the air inlet, and the other end of the air inlet channel is used to connect to the second air chamber;

[0029] One end of the air outlet channel is connected to the air outlet, and the other end of the air outlet channel is used to connect to the second air chamber.

[0030] In one embodiment, a coolant chamber is provided between the second electrode plate and the first electrode plate; the coolant chambers of each conductive assembly plate are interconnected.

[0031] A coolant flow field is provided on the surface of the second electrode plate facing the first electrode plate, and the coolant flow field is located inside the coolant chamber.

[0032] The first electrode plate has a fifth inlet half-shell and a fifth outlet half-shell.

[0033] The second electrode plate has a sixth inlet half-shell and a sixth outlet half-shell.

[0034] The fifth inlet half-shell and the sixth inlet half-shell together form the coolant inlet channel;

[0035] The fifth and sixth outlet half-shells together form the coolant outlet channel;

[0036] The upper pressure block is provided with a coolant inlet and a coolant outlet;

[0037] One end of the coolant inlet channel is connected to the coolant inlet, and the other end of the coolant inlet channel is used to connect to the coolant chamber.

[0038] One end of the coolant outlet channel is connected to the coolant outlet, and the other end of the coolant inlet channel is used to connect to the coolant chamber.

[0039] In one embodiment, the membrane electrode sheet has corresponding openings to allow each air inlet channel to communicate with each other and to allow each air outlet channel to communicate with each other.

[0040] And / or,

[0041] The membrane electrode sheet has corresponding openings to allow each detection gas inlet channel to be interconnected with each detection gas outlet channel;

[0042] And / or,

[0043] The membrane electrode sheet has corresponding openings to allow each coolant inlet channel to be interconnected and each coolant outlet channel to be interconnected.

[0044] In one embodiment, the lower pressing block has a first alignment hole;

[0045] Each conductive assembly plate has a second alignment hole, and each membrane electrode sheet has a third alignment hole.

[0046] When the upper and lower pressing blocks are pressed together, the first alignment hole, the second alignment hole, and the third alignment hole are coaxial.

[0047] In one embodiment, the detected airflow field is formed by a plurality of spaced first flow field ridges arranged in an array, which form one of a parallel flow field, a curved flow field, or a mesh flow field.

[0048] And / or,

[0049] The airflow field is formed by several spaced-apart second flow field ridges, and the first flow field ridges are arranged to form one of the following: parallel flow field, curved flow field or mesh flow field.

[0050] And / or,

[0051] The coolant flow field is formed by several spaced third flow field ridges, while the first flow field ridges are arranged to form one of the following: parallel flow field, curved flow field, or mesh flow field.

[0052] In one embodiment, a voltage testing device is also included, with two test terminals of the voltage testing device respectively positioned on both sides of the membrane electrode sheet.

[0053] In one embodiment, a pressing device is also included, which includes two driving ends, each used to drive the upper pressing block and the lower pressing block to press against each other.

[0054] In one embodiment, both the upper and lower pressure blocks are configured as insulators.

[0055] The aforementioned membrane electrode airtightness testing assembly includes: an upper pressing block, a lower pressing block, several conductive composite plates, and membrane electrode sheets. The upper and lower pressing blocks are arranged opposite each other, with a pressing space between them. Several conductive composite plates are arranged within the pressing space, each including a detection airflow field and an airflow field on both sides; there are clamping gaps between adjacent conductive composite plates, each gap for placing a membrane electrode sheet; the anode side of each membrane electrode sheet forms a first air chamber with the adjacent detection airflow field, and all the first air chambers are interconnected; the cathode side of each membrane electrode sheet forms a second air chamber with the adjacent airflow field, and all the second air chambers are interconnected; the upper pressing block has a detection air inlet and a detection air outlet communicating with the first air chamber, and an air inlet and an air outlet communicating with the second air chamber. This membrane electrode airtightness testing component can use the gap between adjacent conductive composite plates to place membrane electrode sheets in batches, enabling simultaneous testing of multiple sheets and significantly improving testing efficiency. By forming independent and interconnected first and second air chambers with the detection airflow field and the air flow field respectively, it simulates the actual working medium environment of the membrane electrode and ensures testing accuracy. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the assembly of the membrane electrode airtightness detection component provided in an embodiment of this application.

[0057] Figure 2 This is a schematic diagram of the outer side of the first electrode plate provided in an embodiment of this application.

[0058] Figure 3 This is a schematic diagram of the inner side of the first electrode plate provided in an embodiment of this application.

[0059] Figure 4 This is a schematic diagram of the outer side of the second electrode plate provided in an embodiment of this application.

[0060] Figure 5 This is a schematic diagram of the inner side of the second electrode plate provided in an embodiment of this application.

[0061] Figure 6 This is an assembly diagram of the conductive composite board provided in the embodiments of this application.

[0062] Figure 7 This is a partial assembly diagram of the air inlet channel provided in an embodiment of this application.

[0063] Figure 8 This is a schematic diagram of the assembly of ten membrane electrode sheets provided in the embodiments of this application in a membrane electrode airtightness testing assembly.

[0064] Figure 9 for Figure 8 A table showing the voltage difference detection results for each membrane electrode.

[0065] Icon labels:

[0066] 1000, Upper layer pressure block; 1001, Detection air inlet; 1002, Detection air outlet; 1003, Air inlet; 1004, Air outlet; 1005, Coolant inlet; 1006, Coolant outlet;

[0067] 2000, Lower layer pressure block; 2001, First alignment hole;

[0068] 3000, Conductive composite board; 3001, Detection airflow field; 3002, Airflow field; 3003, Coolant flow field; 3004, Second alignment hole;

[0069] 3010, First electrode plate; 3011, First inlet half-shell; 3012, First outlet half-shell; 3013, Third inlet half-shell; 3014, Third outlet half-shell; 3015, Fifth inlet half-shell; 3016, Fifth outlet half-shell;

[0070] 3020, Second electrode plate; 3021, Second inlet half-shell; 3022, Second outlet half-shell; 3023, Fourth inlet half-shell; 3024, Fourth outlet half-shell; 3025, Sixth inlet half-shell; 3026, Sixth outlet half-shell;

[0071] 3030, Detection air inlet channel; 3040, Detection air outlet channel; 3050, Air inlet channel; 3060, Air outlet channel; 3070, Coolant inlet channel; 3080, Coolant outlet channel;

[0072] 4000, Membrane electrode sheet; 4001, Third alignment hole. Detailed Implementation

[0073] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0074] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0075] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0076] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0077] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0078] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0079] See Figures 1-6 As shown, Figure 1 This is a schematic diagram of the assembly of the membrane electrode airtightness detection component provided in an embodiment of this application. Figure 2 This is a schematic diagram of the outer side of the first electrode plate provided in an embodiment of this application. Figure 3 This is a schematic diagram of the inner side of the first electrode plate provided in an embodiment of this application. Figure 4 This is a schematic diagram of the outer side of the second electrode plate provided in an embodiment of this application. Figure 5 This is a schematic diagram of the inner side of the second electrode plate provided in an embodiment of this application. Figure 6 This is a schematic diagram of the assembly of the conductive composite plate provided in an embodiment of this application. The diagram shows a membrane electrode airtightness detection assembly, including: an upper pressing block 1000, a lower pressing block 2000, several conductive composite plates 3000, and a membrane electrode sheet 4000. The upper pressing block 1000 and the lower pressing block 2000 are disposed opposite to each other, with a pressing space between them. Several conductive composite plates 3000 are arranged within the pressing space. Each conductive composite plate 3000 includes a detection airflow field 3001 and an airflow field 3002 disposed on both sides thereon; adjacent conductive composite plates 3000 have clamping gaps, each clamping gap being used to place a membrane electrode sheet 4000.

[0080] Each membrane electrode 4000 has its anode side surrounded by an adjacent detection airflow field 3001 to form a first air chamber, and all the first air chambers are interconnected; each membrane electrode 4000 has its cathode side surrounded by an adjacent airflow field 3002 to form a second air chamber, and all the second air chambers are interconnected; the upper pressure block 1000 is provided with a detection air inlet 1001 and a detection air outlet 1002 that communicate with the first air chamber, and an air inlet 1003 and an air outlet 1004 that communicate with the second air chamber.

[0081] The clamping gap refers to a specific space reserved between two adjacent conductive combination plates 3000 in the membrane electrode airtightness testing assembly for placing the membrane electrode sheet 4000 to be tested. After the membrane electrode airtightness testing assembly is assembled and a preset pressing force is applied, the gap allows the anode side of the membrane electrode sheet 4000 to be tightly fitted with the detection airflow field 3001 of one conductive combination plate, and the cathode side to be tightly fitted with the airflow field 3002 of the other conductive combination plate, thereby forming a sealed first air cavity and a second air cavity respectively. Each clamping gap is only used to accommodate a single membrane electrode sheet 4000, ensuring the independence of the single membrane electrode sheet and the accuracy of the test results during the testing process.

[0082] The detection airflow field 3001 and airflow field 3002 are grooved structures (such as serpentine grooves, parallel grooves, etc.) used to guide gas flow and form a sealed gas cavity with the membrane electrode plate 4000. The detection airflow field 3001 and airflow field 3002 are independent of each other, corresponding to the anode side and cathode side of the membrane electrode plate 4000, respectively. A clamping gap is reserved between two adjacent conductive combination plates 3000, and a membrane electrode plate 4000 to be tested is placed in each gap. The anode side of the membrane electrode plate 4000 and the detection airflow field 3001 of the conductive combination plate 3000 form an independent first gas cavity; the cathode side and the airflow field 3002 of the conductive combination plate 3000 form an independent second gas cavity. All the first gas cavities are connected in series through the through holes on the conductive combination plate 3000 to form an integral detection gas channel, and are connected to an external gas source (such as a detection gas cylinder or pressure pump) through the detection gas inlet 1001 and detection gas outlet 1002 on the upper pressure block 1000.

[0083] All the second air chambers are also connected to form an overall air channel through the interconnection structure of the conductive composite plate 3000, and are connected to an external air source or inert air source through the air inlet 1003 and air outlet 1004 on the upper pressure block 1000.

[0084] The first gas chamber refers to the cavity formed between the anode side of the membrane electrode sheet 4000 to be tested and the detection gas flow field 3001 of the adjacent conductive assembly plate 3000. All the first gas chambers are connected in series through the through holes or semi-shell channels on the conductive assembly plate 3000 to form a connected whole gas path. Detection gas can be introduced through the detection gas inlet 1001 of the upper pressure block 1000 and discharged or closed through the detection gas outlet 1002 to simulate the gas environment on the anode side of the fuel cell membrane electrode. The second gas chamber refers to the closed cavity formed between the cathode side of the membrane electrode sheet 4000 to be tested and the air flow field 3002 (groove structure) of the adjacent conductive combination plate 3000. All the second gas chambers are connected in series through the corresponding channels on the conductive combination plate 3000 to form a connected whole. Air can be introduced through the air inlet 1003 of the upper pressure block 1000 and discharged or closed through the air outlet 1004. It is used to simulate the gas environment on the cathode side of the fuel cell membrane electrode. The first gas chamber and the second gas chamber are isolated by the membrane electrode sheet 4000, are independent and do not communicate with each other, and ensure that the detection medium is not cross-contaminated.

[0085] The first gas chamber on the anode side is filled with detection gas, and the second gas chamber on the cathode side is filled with air (or oxygen) to simulate the actual working medium environment of the membrane electrode in the fuel cell.

[0086] The test gas refers to a specific gas mixture used in the first gas chamber of the membrane electrode airtightness testing component. It is composed of any one of nitrogen, argon, or helium and hydrogen in a specific ratio, with the hydrogen volume percentage strictly controlled within the range of 4% to 8%. The inert gas acts as a diluent to reduce the risk of hydrogen combustion and explosion, ensuring the safety of the testing process. Hydrogen, as the core active component, can simulate the fuel gas on the anode side of a proton exchange membrane fuel cell, providing the necessary electrochemical reaction conditions for subsequent testing of the voltage difference across the membrane electrode 4000 using a voltage testing device and determining whether the airtightness is qualified. At the same time, the composition and concentration of this gas mixture can stably maintain the consistency of the gas environment in the first gas chamber, ensuring the uniformity of the testing conditions for each membrane electrode in batch testing.

[0087] In actual operation of a proton exchange membrane fuel cell, hydrogen (fuel gas) is continuously introduced to the anode side. Under the action of the anode catalyst, the hydrogen undergoes an oxidation reaction, generating protons (H⁺) and electrons (e⁻). The protons migrate through the proton exchange membrane to the cathode side, while the electrons form an electric current through the external circuit. Air (or oxygen, the oxidant) is continuously introduced to the cathode side. Under the action of the cathode catalyst, the oxygen reacts with the protons and electrons that have migrated to the cathode, generating water and completing the conversion of electrical energy. In the membrane electrode airtightness testing component, the first gas chamber is filled with a hydrogen-containing test gas (simulating anode fuel gas), and the second gas chamber is filled with air (simulating cathode oxidant). This precisely replicates the medium type and reaction environment on both sides of the membrane electrode during fuel cell operation. This ensures that the gas atmosphere and possible electrochemical behaviors of the membrane electrode during testing (such as the electrochemical reaction caused by hydrogen and oxygen contact when there is a poor seal) are highly consistent with the actual operating conditions. This guarantees that the test results accurately reflect the airtightness performance of the membrane electrode in actual stacking and avoids testing errors caused by differences between the testing environment and the actual operating environment.

[0088] The flow field structure is consistent with that of a real battery, with uniform gas distribution, enabling accurate detection of the airtightness of the membrane electrode under actual working pressure and medium conditions. Multiple membrane electrode sheets 4000 can be placed one-to-one in the clamping gap simultaneously and tested through a unified airtightness detection system, which improves efficiency several times compared to testing a single sample at a time.

[0089] In the membrane electrode airtightness testing assembly, the clamping gaps are formed only between two adjacent conductive combination plates 3000. Each clamping gap is defined by two conductive combination plates 3000, and there is a one-to-one correspondence between each clamping gap and a membrane electrode sheet 4000. Only one membrane electrode sheet 4000 to be tested is placed in each clamping gap; there is no situation where multiple membrane electrode sheets are placed in one clamping gap. If N membrane electrode sheets 4000 need to be tested, N+1 conductive combination plates 3000 are required (e.g., 11 conductive combination plates are needed to test 10 membrane electrode sheets) to ensure that each membrane electrode sheet can be clamped by two adjacent conductive combination plates and form an independent first air chamber and a second air chamber. Throughout the assembly, pressing, testing, and subsequent disassembly of the assembly, the relationship of "two conductive combination plates corresponding to one clamping gap, and one clamping gap corresponding to one membrane electrode sheet" remains unchanged. This ensures both the independence of the testing environment for each membrane electrode sheet and the stability of the overall assembly structure and the orderly nature of the testing process.

[0090] In some embodiments of this application, the conductive composite plate 3000 is composed of a first electrode plate 3010 and a second electrode plate 3020 assembled together. The detection airflow field 3001 is disposed on the surface of the first electrode plate 3010 facing away from the second electrode plate 3020. The first electrode plate 3010 has a first inlet half-shell 3011 and a first outlet half-shell 3012, and the second electrode plate 3020 has a corresponding second inlet half-shell 3021 and an outlet half-shell 3022. The first inlet half-shell 3011 and the second inlet half-shell 3021 are assembled together to form a detection gas inlet channel 3030, and the first outlet half-shell 3012 and the second outlet half-shell 3022 are assembled together to form a detection gas outlet channel 3040. One end of the detection gas inlet channel 3030 is connected to the detection gas inlet 1001 of the upper pressure block 1000, and the other end is connected to the first gas chamber. The detection gas outlet channel 3040 is connected at one end to the detection gas outlet 1002 of the upper pressure block 1000 and at the other end to the first gas chamber.

[0091] The semi-shell modular channel design reduces processing difficulty, eliminating the need for deep holes in the overall sheet metal and facilitating channel sealing checks. The integrated structure of the detection gas channel and the detection gas flow field 3001 reduces gas leakage points and improves gas path stability. Meanwhile, the combination of double-layer plates enhances the rigidity of the conductive composite plate 3000, effectively preventing structural deformation caused by gas pressure.

[0092] In some embodiments of this application, reference is made to the appendix. Figure 7 , Figure 7 This is a partial assembly diagram of the air inlet channel provided in an embodiment of this application. The airflow field 3002 shown is disposed on the surface of the second electrode plate 3020 facing away from the first electrode plate 3010. The first electrode plate 3010 has a third inlet half-shell 3013 and a third outlet half-shell 3014, and the second electrode plate 3020 has a corresponding fourth inlet half-shell 3023 and a fourth outlet half-shell 3024. The third inlet half-shell 3013 and the fourth inlet half-shell 3023 are assembled to form an air inlet channel 3050, and the third outlet half-shell 3014 and the fourth outlet half-shell 3024 are assembled to form an air outlet channel 3060. One end of the air inlet channel 3050 is connected to the air inlet 1003 of the upper pressure block 1000, and the other end is connected to the second air chamber. One end of the air outlet channel 3060 is connected to the air outlet 1004 of the upper pressure block 1000, and the other end is connected to the second air chamber. Figure 7 This is only one possible configuration for the air inlet channel 3050 described above. Similarly, the air outlet channel 3060, the detection gas outlet channel 3040, and the detection gas inlet channel 3030 can all be configured as described above. Figure 7 The setup principles will not be elaborated further in this article.

[0093] The air channel and the detection gas channel are completely independent and located at different positions on the electrode plate, which can avoid cross-contamination between the two gases and ensure the purity of the detection medium. The symmetrical structural design with the detection gas channel simplifies the processing technology, allows for the use of shared molds to reduce production costs, and the direct connection between the air flow field 3002 and the air channel reduces gas flow resistance, making the gas distribution more uniform.

[0094] In some embodiments of this application, a coolant chamber is provided between the second electrode plate 3020 and the first electrode plate 3010, and the coolant chambers of all conductive composite plates 3000 are interconnected; a coolant flow field 3003 is provided on the surface of the second electrode plate 3020 facing the first electrode plate 3010, located within the coolant chamber; a fifth inlet half-shell 3015 and a fifth outlet half-shell 3016 are formed on the first electrode plate 3010, and a sixth inlet half-shell 3025 and a sixth outlet half-shell 3026 are correspondingly formed on the second electrode plate 3020. The fifth inlet half-shell 3015 and the sixth inlet half-shell 3025 are joined together to form a coolant inlet channel 3070. The fifth outlet half-shell 3016 and the sixth outlet half-shell 3026 are joined together to form a coolant outlet channel 3080. The upper pressure block 1000 has a coolant inlet 1005 and a coolant outlet 1006. One end of the coolant inlet channel 3070 is connected to the coolant inlet 1005 and the other end is connected to the coolant chamber. One end of the coolant outlet channel 3080 is connected to the coolant outlet 1006 and the other end is connected to the coolant chamber.

[0095] The coolant system can simulate the cooling environment during fuel cell operation, avoiding deformation of the membrane electrode 4000 due to temperature differences when the detection gas or air is introduced, thus ensuring the accuracy of the airtightness test. The coolant flow field 3003 enhances the heat exchange efficiency, ensuring that all membrane electrode 4000s are under the same temperature conditions, improving the consistency of the test results. At the same time, the coolant chamber is completely isolated from the gas path, which can prevent liquid leakage from interfering with gas detection.

[0096] In some embodiments of this application, the membrane electrode 4000 has through holes at the positions corresponding to the air inlet channel 3050, air outlet channel 3060, detection gas inlet channel 3030, detection gas outlet channel 3040, coolant inlet channel 3070, and coolant outlet channel 3080. These holes only allow the corresponding channels to pass through and do not affect the sealing and adhesion between the membrane electrode 4000 and the flow field. The holes enable all the air inlet channels 3050, air outlet channels 3060, detection gas inlet channels 3030, detection gas outlet channels 3040, coolant inlet channels 3070, and coolant outlet channels 3080 to be interconnected. The perforated design enables batch parallel testing of multiple membrane electrode sheets 4000 without the need for separate gas or liquid circuit connections for each conductive assembly board 3000, greatly simplifying the equipment structure. At the same time, it ensures that all membrane electrode sheets 4000 are under the same gas pressure, flow rate, and temperature conditions, making the test results comparable. Furthermore, the perforation position precisely avoids the effective detection area of ​​the membrane electrode sheet 4000, without affecting the authenticity of the test.

[0097] In some embodiments of this application, the lower pressing block 2000 has a first alignment hole 2001, each conductive assembly plate 3000 has a second alignment hole 3004, and each membrane electrode sheet 4000 has a third alignment hole 4001. When the upper pressing block 1000 and the lower pressing block 2000 are pressed together, the first alignment hole 2001, the second alignment hole 3004, and the third alignment hole 4001 are coaxial and can be precisely positioned by a locating pin.

[0098] The alignment hole structure solves the misalignment problem during the assembly of multi-layer components, avoiding poor air cavity sealing due to flow field alignment deviation (such as incomplete compression of the membrane electrode sheet 4000); at the same time, it improves assembly efficiency, eliminates the need for repeated position adjustments, is suitable for industrial batch operations, and reduces excessive local pressure caused by misalignment, thus protecting the membrane electrode sheet 4000 (a brittle material) from damage.

[0099] In some embodiments of this application, the detection airflow field 3001 is formed by a plurality of spaced-apart first flow field ridges, the airflow field 3002 is formed by a plurality of spaced-apart second flow field ridges, and the coolant flow field 3003 is formed by a plurality of spaced-apart third flow field ridges. These ridge arrangements can form one of a parallel flow field, a curved flow field, or a mesh flow field. The ridge height matches the thickness of the membrane electrode sheet 4000 to ensure a seal. The ridge structure achieves a seal by pressing the edge of the membrane electrode sheet 4000, while the flow channel grooves ensure smooth flow of gas or liquid. The flow field type can be selected according to the size of the membrane electrode sheet 4000 and the detection accuracy requirements, such as a parallel flow field for small-area samples and a curved flow field for high-precision detection, making it highly adaptable. The flow field and ridges are integrated into the fabrication process, resulting in a stable structure and a long service life.

[0100] In some embodiments of this application, the two test terminals of the voltage testing device are respectively connected to both sides of the membrane electrode 4000. One end is connected to the first electrode plate 3010 of the conductive composite plate 3000, which is in contact with the anode side of the membrane electrode 4000, via a wire, and the other end is connected to the second electrode plate 3020 of the conductive composite plate 3000, which is in contact with the cathode side of the membrane electrode 4000, via a wire. The connection point between the test terminal and the electrode plate avoids the flow field region so as not to interfere with the gas flow.

[0101] In some embodiments of this application, the electrochemical properties of the membrane electrode 4000 are used to detect air tightness. If the seal is good, the detection gas (anode) does not come into contact with the air (cathode), no current is generated, and the voltage difference is stable. If there is a leak, the detection gas reacts with oxygen to generate current, and the voltage difference drops significantly. The detection sensitivity is much higher than that of simple pressure detection. The sealing status of each membrane electrode 4000 can be monitored in real time, and leaked samples can be quickly located. No additional leak detection sensors are required, which reduces equipment costs.

[0102] In some embodiments of this application, the pressing device includes two drive ends, respectively connected to the upper pressing block 1000 and the lower pressing block 2000. The drive ends can be pneumatic cylinders, hydraulic cylinders, or lead screw transmission mechanisms. During pressing, a preset pressure is applied, and the pressure is adjusted by feedback from a pressure sensor to ensure uniform distribution of the pressing force. This provides a stable and adjustable pressing force, ensuring a good seal between the membrane electrode 4000 and the flow field. Insufficient pressure can easily lead to leakage, while excessive pressure can damage the membrane electrode. Automated pressing replaces manual operation, reducing labor intensity and improving pressure consistency. It also facilitates rapid sample loading and unloading, improving detection efficiency.

[0103] In some embodiments of this application, both the upper pressing block 1000 and the lower pressing block 2000 are configured as insulators.

[0104] After the membrane electrode sheet 4000 is placed in the clamping gap, the upper pressing block 1000 and the lower pressing block 2000 are pressed together.

[0105] Detection gas is introduced into the first gas chamber through the detection gas inlet 1001 until the detection gas is detected at the detection gas outlet 1002, and then the detection gas outlet 1002 is closed.

[0106] Air is introduced into the second air chamber through the air inlet 1003 until air is detected at the air outlet 1004, after which the air outlet 1004 is closed. The voltage difference across each membrane electrode 4000 is measured. The detection process is simple, requires no complex operations, and is suitable for rapid testing on production lines; the gas passage venting step avoids residual air in the pipeline affecting the detection results; and leakage is determined using the voltage difference.

[0107] The specific testing implementation scheme of the membrane electrode airtightness testing component is as follows: First, assemble the membrane electrode airtightness testing component as described above, ensuring precise alignment of each component by passing positioning pins through the first alignment hole 2001 of the lower layer pressing block 2000, the second alignment hole 3004 of the conductive combination plate 3000, and the third alignment hole 4001 of the membrane electrode sheet 4000; then, start the pressing device, driving the upper layer pressing block 1000 and the lower layer pressing block 2000 to press against each other through its two drive ends, applying a pressing force to make the membrane electrode sheet 4000 tightly adhere to the detection airflow field 3001 and airflow field 3002 of the conductive combination plates on both sides, forming a sealed first air chamber and second air chamber; subsequently, start the coolant circulation system, circulating coolant through the coolant inlet 1005 of the upper layer pressing block 1000 into the coolant chamber of the conductive combination plate 3000 to maintain the temperature of the membrane electrode sheet 4000. The operating temperature of the simulated fuel cell is set. Next, detection gas is introduced into the first gas chamber through the detection gas inlet 1001. After the gas detector at the detection gas outlet 1002 detects the detection gas (confirming that there is no residual air in the first gas chamber and the connecting channel), the detection gas outlet 1002 is closed. At the same time, air is introduced into the second gas chamber through the air inlet 1003. After a stable airflow is detected at the air outlet 1004 (confirming that there is no residual gas in the second gas chamber and the connecting channel), the air outlet 1004 is closed. Finally, the two test terminals of the voltage test device are connected to the conductive combination plates 3000 (first plate 3010 and second plate 3020) on both sides of the membrane electrode 4000, respectively. The voltage difference on both sides of each membrane electrode 4000 is measured. If the voltage difference is stable within the preset reference range, the air tightness is qualified. If the voltage difference is significantly lower than the reference value, the air tightness is determined to be unqualified.

[0108] By employing a design with multiple sets of conductive composite plates and clamping gaps, multiple membrane electrode assemblies (MEAs) can be inspected simultaneously, significantly improving inspection efficiency and meeting the needs of industrial mass production. Precise positioning and stable pressing ensure consistent sealing conditions and gas contact states for each MEA during inspection, reducing inspection errors. By simulating the actual working medium environment and temperature conditions of a fuel cell, combined with the high sensitivity of voltage detection, minute leakage defects in MEAs, such as pinholes and poor encapsulation, can be accurately identified. Defective MEAs can be directly located, avoiding the need for disassembly and troubleshooting required in traditional inspection methods. Furthermore, it eliminates the need for complex pressure calibration equipment, reducing inspection costs and operational complexity.

[0109] For specific examples, see below. (Reference) Figure 8 , Figure 8This is a schematic diagram of the assembly of ten membrane electrode sheets 4000 provided in this application embodiment in a membrane electrode airtightness testing assembly. The experiment demonstrates a scenario where airtightness testing is performed simultaneously on ten membrane electrode sheets 4000. Correspondingly, eleven conductive assembly plates 3000 are provided. The ten membrane electrode sheets 4000 are sequentially numbered a1-a10. The test results are shown in the table below. Figure 9 , Figure 9 for Figure 8 The table shows the voltage difference test results for each membrane electrode 4000. The voltage difference between the two sides of membrane electrode 4000 of a7 and a9 is significantly lower than that of other membrane electrode 4000. The voltage difference of other membrane electrode 4000 is normal, which indicates that the airtightness of membrane electrode 4000 of a7 and membrane electrode 4000 of a9 is unqualified.

[0110]

[0111] 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.

[0112] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A membrane electrode airtightness detection component, characterized in that, include: An upper pressing block and a lower pressing block disposed opposite to the upper pressing block; There is a pressing space between the upper pressing blocks; Several conductive composite plates are arranged within the pressing space; Each of the conductive composite plates includes a detection airflow field and an airflow field disposed on both sides thereof; There are clamping gaps between adjacent conductive composite plates, and each clamping gap is used to place a membrane electrode sheet; The anode side of each membrane electrode sheet is surrounded by the adjacent detection gas flow field to form a first gas chamber, and all the first gas chambers are interconnected. The cathode side of each of the membrane electrode sheets forms a second air chamber with the adjacent air flow field, and all the second air chambers are interconnected. The upper pressure block is provided with a detection air inlet and a detection air outlet communicating with the first air chamber, and an air inlet and an air outlet communicating with the second air chamber.

2. The membrane electrode airtightness detection component according to claim 1, characterized in that, The conductive composite plate includes a first electrode plate and a second electrode plate that are connected to each other. The detection airflow field is disposed on the surface of the first electrode plate opposite to the second electrode plate; The first electrode plate has a first inlet half-shell and a first outlet half-shell. The second electrode plate is provided with a second inlet half-shell and a second outlet half-shell; The first inlet half-shell and the second inlet half-shell together form a detection gas inlet channel; The second inlet half-shell and the second outlet half-shell together form the detection gas outlet channel; One end of the detection gas inlet channel is connected to the detection gas inlet, and the other end of the detection gas inlet channel is used to connect to the first gas chamber; One end of the detection gas outlet channel is connected to the detection gas outlet, and the other end of the detection gas outlet channel is used to connect to the first gas chamber.

3. The membrane electrode airtightness detection component according to claim 2, characterized in that, The airflow field is disposed on the surface of the second electrode plate opposite to the first electrode plate; The first electrode plate has a third inlet half-shell and a third outlet half-shell; The second electrode plate has a fourth inlet half-shell and a fourth outlet half-shell. The third inlet half-shell and the fourth inlet half-shell together form an air inlet channel; The third outlet half-shell and the fourth outlet half-shell together form an air outlet channel; One end of the air inlet channel is connected to the air inlet, and the other end of the air inlet channel is used to connect to the second air chamber; One end of the air outlet channel is connected to the air outlet, and the other end of the air outlet channel is used to connect to the second air chamber.

4. The membrane electrode airtightness detection component according to claim 3, characterized in that, A coolant chamber is provided between the second electrode plate and the first electrode plate; the coolant chambers of each conductive composite plate are interconnected. A coolant flow field is provided on the surface of the second electrode plate facing the first electrode plate, and the coolant flow field is located inside the coolant chamber; The first electrode plate has a fifth inlet half-shell and a fifth outlet half-shell; The second electrode plate has a sixth inlet half-shell and a sixth outlet half-shell. The fifth inlet half-shell and the sixth inlet half-shell together form a coolant inlet channel; The fifth outlet half-shell and the sixth outlet half-shell together form a coolant outlet channel; The upper pressure block is provided with a coolant inlet and a coolant outlet; One end of the coolant inlet channel is connected to the coolant inlet, and the other end of the coolant inlet channel is used to connect to the coolant chamber; One end of the coolant outlet channel is connected to the coolant outlet, and the other end of the coolant inlet channel is used to connect to the coolant chamber.

5. The membrane electrode airtightness detection component according to claim 4, characterized in that, The membrane electrode sheet has corresponding openings to allow each air inlet channel to communicate with each other, and to allow each air outlet channel to communicate with each other. And / or, The membrane electrode sheet has corresponding openings to allow each of the detection gas inlet channels to communicate with each other, and to allow each of the detection gas outlet channels to communicate with each other. And / or, The membrane electrode sheet has corresponding openings to allow each coolant inlet channel to communicate with each other, and to allow each coolant outlet channel to communicate with each other.

6. The membrane electrode airtightness detection component according to claim 5, characterized in that, The lower layer pressing block is provided with a first alignment hole; Each of the conductive assembly plates is provided with a second alignment hole, and each of the membrane electrode sheets is provided with a third alignment hole; When the upper pressing block and the lower pressing block are pressed together, the first alignment hole, the second alignment hole and the third alignment hole are coaxial.

7. The membrane electrode airtightness detection component according to claim 4, characterized in that, The detected airflow field is formed by several spaced-apart first flow field ridges, which form one of a parallel flow field, a curved flow field, or a mesh flow field. And / or, The airflow field is formed by several spaced-apart second flow field ridges, and the first flow field ridges are arranged to form one of a parallel flow field, a curved flow field, or a mesh flow field. And / or, The coolant flow field is formed by several spaced third flow field ridges, and the first flow field ridges are arranged to form one of a parallel flow field, a curved flow field, or a mesh flow field.

8. The membrane electrode airtightness detection component according to claim 1, characterized in that, It also includes a voltage testing device, the two test terminals of which are respectively used to be set on both sides of the membrane electrode sheet.

9. The membrane electrode airtightness detection component according to claim 1, characterized in that, It also includes a pressing device, which has two driving ends, each of which is used to drive the upper pressing block and the lower pressing block to press against each other.

10. The membrane electrode airtightness detection component according to claim 1, characterized in that, Both the upper and lower pressure blocks are configured as insulators.

Images