A test method for evaluating membrane electrodes under simulated over-humidity conditions

Abstract

This invention pertains to the field of hydrogen fuel cells, specifically a test method for evaluating membrane electrode assemblies (MEAs) under simulated excessively humid conditions. This method involves setting the stack temperature to be 2–10°C lower than the inlet temperatures of hydrogen and air during polarization performance and humidity sensitivity testing of small-sized MEA single cells (where the stack temperature is T). S The intake temperature of hydrogen and air is T. IC and T IA That is, by using T S Adjusted to be T IC and T IA The temperature is lowered by 2 to 10°C, thus artificially creating an "over-humidified" phenomenon inside the battery, and the performance of the membrane electrode under over-humidified conditions is evaluated accordingly. Compared with the prior art, this invention can predict the performance stability of the membrane electrode under the "over-humidified" condition in a short stack through single-cell testing of small-sized membrane electrodes, fill the gap in the poor consistency between single-cell test results of small-sized membrane electrodes and test results of full-size membrane electrode stacks, and greatly reduce the research and development cost.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen fuel cells, specifically a test method for evaluating membrane electrodes under simulated excessively humid conditions. Background Technology

[0002] my country has long faced the energy challenge of oil and gas shortages, and hydrogen energy is an important strategic energy source for addressing this challenge. Currently, the most efficient energy conversion method for hydrogen energy is through power generation via polymer electrolyte membrane fuel cells (PEMFCs). The membrane electrode assembly (MEA) is the core component of the fuel cell that converts chemical energy into electrical energy through the chemical reaction of hydrogen and oxygen. Its cost, performance, and lifespan have a crucial impact on the fuel cell stack and system.

[0003] In fuel cell stacks, the large active area and numerous membrane electrode assemblies (MEAs) pose significant challenges to controlling internal temperature, humidity, and reactant concentration. Within a stack, hundreds of MEAs may experience substantial voltage, temperature, and humidity fluctuations from start to finish, leading to single or multiple MEAs experiencing "water shortage" or "water flooding." This results in a voltage significantly lower than adjacent MEAs, potentially causing reverse polarity, catalyst layer corrosion, or even overheating and proton exchange membrane perforation. Therefore, it is necessary to develop MEAs adaptable to a wider temperature and humidity range to alleviate the burden on stack and system control.

[0004] In the development of membrane electrodes, due to the small size of membrane electrodes (active area 25–50 cm²), 2 Single-cell testing using small-sized membrane electrodes (MEAs) is the most common testing method due to its low raw material consumption, simple assembly, highly customizable testing fixtures, and low energy consumption. With continuous improvements in testing fixture design and test bench control, single-cell testing with small-sized MEAs can now achieve high uniformity of temperature, humidity, and reactant concentration within the active region of the MEA. Therefore, the single-cell test results of small-sized MEAs typically reflect the performance of the corresponding MEA configuration under stable and uniform temperature and humidity control.

[0005] However, in the development of membrane electrode assemblies (MEAs), discrepancies often arise between the evaluation results of small-sized MEA single cells and full-sized MEA stacks with the same configuration. This is because in full-sized MEA stacks (tens to hundreds of cells), temperature and humidity fluctuations are more pronounced, and the distribution of reactant gases is uneven, causing localized "over-humidification" of single or several MEAs. This can even affect adjacent MEAs, resulting in significant voltage fluctuations and greatly increasing the risk of reverse polarity, threatening the lifespan of both the MEAs and the stack. For example, a single cell with a small-sized MEA configuration may show excellent performance, while a full-sized MEA with the same configuration may exhibit low performance and large voltage fluctuations in a stack.

[0006] Therefore, it is necessary to develop a test method that can reproduce the "over-wetness" phenomenon in the stack during the single-cell test of small-sized membrane electrode, and use this method to evaluate the performance of the membrane electrode under extreme conditions, so as to make a more accurate prediction of the performance of the corresponding membrane electrode configuration in the stack. Summary of the Invention

[0007] The purpose of this invention is to address the above-mentioned shortcomings by providing a test method for evaluating membrane electrodes under simulated over-wet conditions. This method can predict the performance stability of membrane electrodes in short stacks under "over-wet" conditions through single-cell testing of small-sized membrane electrodes, thus filling the gap in the poor consistency between single-cell test results of small-sized membrane electrodes and test results of full-size membrane electrode stacks, and greatly reducing research and development costs.

[0008] To achieve the above objectives, a test method for evaluating membrane electrodes under simulated excessively humid conditions was designed. In the polarization performance and humidity sensitivity tests of small-sized membrane electrode single cells, the stack temperature was set to be 2–10°C lower than the inlet temperatures of hydrogen and air, with the stack temperature being T. S The intake temperature of hydrogen and air is T. IC and T IA That is, by T S Adjusted to be T IC and T IA The temperature was lowered by 2 to 10°C, thus artificially creating an "over-humidified" phenomenon inside the battery, and the performance of the membrane electrode under over-humidified conditions was evaluated accordingly.

[0009] Furthermore, the polarization performance test under excessively humid conditions of the present invention includes the following steps: 1) Assemble the membrane electrode into a single cell, connect the single cell to the hydrogen and air gas path of the test bench, connect the single cell to the water path of the test bench to control the stack temperature through water temperature, and connect the voltage test clamp. 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) Edit the test plan on the test bench computer and create an "over-humidified" environment by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature; 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and analyze it.

[0010] Furthermore, in step 3), when editing the test plan on the test bench computer, the parameters for the polarization curve test under the over-humidity condition are set according to the following (i.e., as shown in the attached diagram of the instruction manual). Figure 8 ).

[0011] Furthermore, the humidity sensitivity test under excessively humid conditions of the present invention includes the following steps: 1) Assemble the membrane electrode into a single cell, connect the single cell to the hydrogen and air gas path of the test bench, connect the single cell to the water path of the test bench to control the stack temperature through water temperature, and connect the voltage test clamp. 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) Edit the test plan on the test bench computer and create "over-humidity" conditions by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature; 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and analyze it.

[0012] Furthermore, in step 3), when editing the test plan on the test bench computer, the humidity sensitivity test settings for the excessively humid conditions are as follows (i.e., as shown in the attached diagram of the instruction manual). Figure 9 ).

[0013] Furthermore, before the test, operating parameters are input according to the test plan; during the test, the reactant gas, carrying water vapor, enters the cathode / anode flow channel through the pipeline after passing through the humidifier; the gas temperature is controlled by the heating belt wrapped around the intake pipe and the sensor, i.e., the intake temperature T. IC and T IA The humidity of the gas is determined by both the dew point temperature controlled by the humidifier and the inlet air temperature. The dew point temperature is T. DC and T DA The fuel cell stack temperature is controlled by a fuel cell stack temperature sensor, a fuel cell stack heating device, and a fan. The fuel cell stack temperature is T. S By T S Adjusted to be T IC and T IA The temperature was lowered by 2–10°C to create an excessively humid environment inside the battery, and the discharge performance of the membrane electrode under these extreme conditions was evaluated.

[0014] Compared with the prior art, the present invention has the following advantages: (1) The present invention can predict the performance stability of the membrane electrode when the membrane electrode is "over-wet" in the short stack by testing a single cell of a small-size membrane electrode, which fills the gap in the poor consistency between the test results of a single cell of a small-size membrane electrode and the test results of a full-size membrane electrode stack. The membrane electrode configuration selected by the test method of the present invention has higher compatibility with the full-size membrane stack.

[0015] (2) This invention is applicable to both membrane electrode polarization curve and humidity sensitivity testing, and has a strong ability to identify differences in membrane electrode performance.

[0016] (3) This invention does not require equipment modification. It only adjusts the temperature of the fuel cell stack to make it lower than the inlet temperature, thereby causing partial condensation of water vapor in the reaction gas and resulting in the phenomenon of "over-humidification" inside the membrane electrode.

[0017] (4) This invention continues the advantages of small-size membrane electrode single cell testing, such as material saving, simplicity, high adjustability and low energy consumption. It can promote the rapid iteration of membrane electrode design and development. In particular, given the recent surge in raw material (especially precious metal) prices caused by international tensions, improving the consistency of small-size membrane electrode single cell and stack performance evaluation through this invention can greatly reduce R&D costs. In summary, this invention enables a more accurate evaluation of the membrane electrode configuration before stack testing, thereby significantly reducing the number of full-size membrane electrode stack tests, shortening the membrane electrode development cycle, and saving considerable R&D costs, making it worthy of widespread application. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a single-cell test of the small-sized membrane electrode of the present invention; Figure 2 This is a polarization curve of the MEA-1 and MEA-2 small-size membrane electrode single cells in Embodiment 1 of the present invention under the superhumid conditions of 80°C and 100%RH. Figure 3 This is a polarization curve of the MEA-1 and MEA-2 small-size membrane electrode single cells in Embodiment 1 of the present invention under conventional conditions of 80°C and 100%RH. Figure 4 The MEA-1 and MEA-2 small-sized membrane electrode single cells in Embodiment 2 of the present invention, under different humidity conditions at 65°C, achieve an A / cm² performance of 1.0 A / cm². 2 Voltage fluctuation graph; Figure 5 The MEA-1 and MEA-2 small-sized membrane electrode single cells in Embodiment 2 of this invention achieve an A / cm² speed of 1.0 A / cm² under normal conditions at 65°C and different humidity levels. 2 Voltage fluctuation graph; Figure 6 This embodiment of the invention uses a fuel cell stack equipped with 10 full-size MEA-1 film electrodes at 65°C, 60 / 40%RH (cathode / anode), 120 / 120 kPa (cathode / anode), and 0.9 A / cm. 2 Fluctuation graph of voltage value of single-film electrode; Figure 7 This embodiment of the invention uses a fuel cell stack equipped with 10 full-size MEA-2 membrane electrodes at 65°C, 60 / 40%RH (cathode / anode), 120 / 120 kPa (cathode / anode), and 0.9 A / cm. 2 Fluctuation graph of voltage value of single-film electrode; Figure 8 This is the parameter setting table for the polarization curve test under excessive humidity conditions of this invention; Figure 9This is the parameter setting table for humidity sensitivity testing under excessively humid conditions according to the present invention; Figure 10 This is a membrane electrode configuration table according to an embodiment of the present invention. Detailed Implementation

[0019] This invention provides a testing method for polymer electrolyte membrane electrode single cells to evaluate the reliability of the membrane electrode in a fuel cell stack. Specifically, it is a testing method for evaluating the membrane electrode under simulated excessively humid conditions. This testing method involves setting the stack temperature (T) during polarization performance testing (IV curve) and humidity sensitivity testing of small-sized membrane electrode single cells. S The inlet temperature of hydrogen and air (T) IC and T IA The temperature was lowered by 2-10°C to artificially create an "over-humidified" environment inside the battery, and this was used to evaluate the performance of the membrane electrode.

[0020] As one embodiment of the present invention, the polarization performance test under excessively humid conditions includes the following steps: 1) Assemble the membrane electrode assembly into a single cell, connect the single cell to the gas path (hydrogen, air) and water path (controlling the stack temperature via water temperature) of the test bench, and connect the voltage test clamp (e.g., Figure 1 ); 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) According to as follows Figure 8 The parameter table shown is used to edit the test plan on the test bench computer. An "over-humidified" environment is created by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature. 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and analyze it.

[0021] As another embodiment of the present invention, the humidity sensitivity test under excessively humid conditions includes the following steps: 1) Assemble the membrane electrode assembly into a single cell, connect the single cell to the gas path (hydrogen, air) and water path (controlling the stack temperature via water temperature) of the test bench, and connect the voltage test clamp (e.g., Figure 1 ); 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) According to as follows Figure 9 The parameter table shown is used to edit the test plan on the test bench computer. The "over-humidity" condition is created by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature. 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and analyze it.

[0022] This invention sets the dew point temperature (T) DC and T DA ), intake air temperature (T) IC and T IA ) and stack temperature (T S The process involves switching between routine and over-humidity tests. During routine testing, the stack temperature is set to be the same as the inlet gas temperature, and the dew point temperature is adjusted to achieve the appropriate hydrogen / air humidity. During the tests according to this invention, the inlet gas temperature and dew point temperature are the same as in routine testing, except that the stack temperature at the corresponding test point is lowered by 2–10°C. When testing under the conditions of this invention, because the inlet gas temperature is higher than the stack temperature, the water vapor carried by the gas will condense to some extent after entering the flow channel due to the relatively low ambient temperature. This condensation forms small droplets on the surface of the gas diffusion layer, increasing the resistance to the diffusion of the reactant gas to the catalyst layer and degrading the membrane electrode performance. In extreme cases, the increased liquid water in the flow channel can clog the gas diffusion layer and the flow channel, causing severe "flooding." This invention assesses the stability of the membrane electrode's power generation performance under extreme conditions by artificially creating an "over-humidity" phenomenon. Combining this assessment result with the test results under routine operating conditions allows for the selection of a membrane electrode configuration more suitable for the stack application.

[0023] As attached Figure 1 The diagram shown illustrates a single-cell test using a small-sized membrane electrode assembly. Before testing, the operating parameters are input according to the test plan (see [link]). Figure 8 and Figure 9 During the test, the reactant gas, carrying water vapor, enters the cathode / anode flow channel through a pipeline after passing through a humidifier; the gas temperature is controlled by a heating belt wrapped around the inlet pipe and a sensor (i.e., inlet temperature T). IC and T IA The humidity of the gas is controlled by the dew point temperature (T) of the humidifier. DC and T DA ) and intake air temperature (T IC and T IA The temperature of the fuel cell stack is determined jointly by the fuel cell stack temperature sensor (T). S The fuel cell stack heating device and fan are jointly controlled; during routine testing, the set temperature at any test point = T S =T IC =T IA The present invention uses T S Adjusted to be T IC and T IA The temperature was lowered by 2–10°C to create an excessively humid environment inside the battery, and the discharge performance of the membrane electrode under these extreme conditions was evaluated.

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: Example 1: Polarization curve test under excessively humid conditions 1. As follows Figure 10 The configuration table shown is used for membrane electrode assembly. The cathode catalytic layer and gas diffusion layer of the two membrane electrodes are different. 2. Assemble the assembled membrane electrode MEA-1 into a single cell, connect the single cell to the gas path (hydrogen, air) and water path (control the stack temperature through water temperature) of the test bench, and connect the voltage test clamp; 3. Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 4. According to as follows Figure 8 The parameter table shown is used to edit the test plan on the test bench computer. An "over-humidified" environment is created by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature. 5. Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 6. Repeat steps 2-5 to complete the testing of the membrane electrode MEA-2; 7. Export the data and perform analysis; 8. Evaluate the performance stability of MEA-1 and MEA-2 under excessively humid conditions.

[0025] like Figure 2 As shown, the power generation performance of MEA-1 in the low to medium current density stage is almost the same as that of MEA-2; when the current density rises to 1.5 A / cm 2 At and above this level, the voltage difference between MEA-1 and MEA-2 gradually widens; at 2.0 A / cm 2 The voltage of MEA-1 is 33mV higher than that of MEA-2; MEA-2 is at 2.0A / cm 2 A noticeable inflection point appeared afterward, and it even became unable to withstand a load of 2.5 A / cm. 2 This indicates that MEA-2 experienced significant flooding during the testing process.

[0026] The above results indicate that MEA-1 outperforms MEA-2 under excessively humid conditions, maintaining high-power discharge (high voltage and high current density) even in excessively humid conditions (where liquid water is generated). In contrast, MEA-2 experiences a sharp voltage drop with increasing discharge power under excessively humid conditions, and may even fail to reach its maximum discharge current density.

[0027] In contrast, when using conventional polarization performance test parameters, that is... Figure 8 The fuel cell stack temperature in the table is set to 80°C, the same as the inlet air temperature. The test results are as follows: Figure 3 Under normal operating conditions, MEA-2 is only 6–11 mV lower than MEA-1 in the high electrical density region, with no significant difference; therefore, it is difficult to distinguish the resistance of MEA-1 and MEA-2 to extreme humidity environments under normal operating conditions. Figure 2 and Figure 3 The polarization curves of MEA-1 and MEA-2 small-size membrane electrode single cells under (a) over-humidified and (b) normal conditions at 80°C and 100%RH are shown, respectively.

[0028] Example 2: Humidity Sensitivity Test under Excessive Humidity Conditions 1. As in Example 1 Figure 10 The configuration table shown is used for membrane electrode assembly. The cathode catalytic layer and gas diffusion layer of the two membrane electrodes are different. 2. Assemble the assembled membrane electrode MEA-1 into a single cell, connect the single cell to the gas path (hydrogen, air) and water path (control the stack temperature through water temperature) of the test bench, and connect the voltage test clamp; 3. Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 4. According to as follows Figure 9 The parameter table shown is used to edit the test plan on the test bench computer. The "over-humidity" condition is created by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature. 5. Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 6. Repeat steps 2–5 to complete the testing of the membrane electrode MEA-2; 7. Export the data and perform analysis; 8. Evaluate the humidity sensitivity of MEA-1 and MEA-2 under excessively humid conditions at 65°C.

[0029] like Figure 4 As shown, MEA-1 was tested at 65℃, 30%, 60%, 80%, and 100% RH, with an A / cm² temperature. 2 The voltage value at the current density is relatively high, the voltage fluctuation is small, and the voltage range (highest voltage minus lowest voltage) is 4mV. Under the same conditions, although the voltage of MEA-2 is very close to that of MEA-2 at 30% and 60%RH, the voltage drops sharply at 80% and 100%RH, with a voltage range of 25mV.

[0030] The above results indicate that MEA-1 exhibits minimal voltage fluctuation with humidity variation under excessively humid conditions (range 4 mV) and a relatively high average voltage (0.731 V). In contrast, MEA-2's voltage drops sharply under higher humidity conditions, indicating significant mass transfer polarization under these conditions (range 25 mV, average voltage 0.720 V). Therefore, MEA-1 demonstrates better performance and stability compared to MEA-2.

[0031] In contrast, when using conventional humidity sensitivity test parameters, that is... Figure 9 The fuel cell stack temperature in the table is set to 65°C, the same as the inlet air temperature. The test results are as follows: Figure 5 Under normal operating conditions, the voltage fluctuation of MEA-2 under different humidity levels (range 5 mV, average voltage 0.725 V) is much smaller than that under excessive humidity conditions, and the difference between MEA-2 and MEA-1 (range 4 mV, average voltage 0.726 V) is minimal. Therefore, humidity sensitivity tests under normal operating conditions are also difficult to distinguish the resistance of MEA-1 and MEA-2 to extreme humidity environments. Figure 4 and Figure 5 The single cells of MEA-1 and MEA-2 small-sized membrane electrode assemblies were tested at 1.0 A / cm² under different humidity conditions (a) and (b) at 65°C. 2 The voltage value.

[0032] To verify the reliability of this invention in evaluating the membrane electrode's performance against excessively humid environments, full-size membrane electrodes (active area 300–400 cm²) were fabricated according to the membrane electrode configurations of MEA-1 and MEA-2. 2 Short heap (10 sections) test. For example... Figure 6 and Figure 7 As shown, the fuel cell stack equipped with the MEA-1 full-size film electrode operates at its rated point (0.9 A / cm). 2 The first stack exhibits a relatively high single-electrode voltage (average voltage 0.778 V) and small voltage fluctuation (range 7 mV), while the stack equipped with a full-size MEA-2 membrane electrode exhibits a relatively low single-electrode voltage (average voltage 0.757 V), with the voltage decreasing further towards the end of the stack, reaching a range as high as 62 mV. Considering the rated operating conditions, the high humidity easily creates a humidity environment far exceeding the set operating conditions near the gas outlet in the active area of ​​the membrane electrode. Furthermore, the MEA-2 membrane electrode cannot efficiently remove water generated in the catalyst layer during power generation, resulting in high mass transfer polarization due to "over-wetting" of the catalyst layer. This phenomenon is further exacerbated at the relatively lower temperature end of the stack, causing a significant decrease in the voltage of the tail-end membrane electrode. Figure 6 and Figure 7 The test results were obtained by comparing a fuel cell stack equipped with (a) 10 full-size MEA-1 membrane electrodes and a fuel cell stack equipped with (b) 10 full-size MEA-2 membrane electrodes at 65°C, 60 / 40%RH (cathode / anode), 120 / 120 kPa (cathode / anode), and 0.9 A / cm. 2 The voltage value of a single membrane electrode.

[0033] The results of the full-size membrane electrode stack tests above show good consistency with the polarization and humidity sensitivity test results of the small-size membrane electrode single cell used in this invention under excessively humid conditions. Compared with the small-size membrane electrode single cell tests under conventional conditions, this invention can more effectively predict the tolerance of a membrane electrode to temperature and humidity fluctuations in a full-size membrane electrode stack. This invention increases the correlation between small-size membrane electrode single cell tests and full-size membrane electrode stack tests, allowing for a more accurate evaluation of the membrane electrode configuration before stack testing. It can significantly reduce the number of full-size membrane electrode stack tests, shorten the membrane electrode development cycle, and save considerable R&D costs.

[0034] The contents not described in detail in this specification are existing technologies known to those skilled in the art. The standard parts used can be purchased from the market, and the irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods in the prior art, and the circuit connections adopt conventional connection methods in the prior art, which will not be described in detail here.

[0035] This invention is not limited to the above-described embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of this invention shall be considered equivalent substitutions and shall be included within the scope of protection of this invention.

Claims

1. A test method for evaluating membrane electrodes under simulated over-humidity conditions, characterized in that: By setting the temperature of the stack to be 2-10℃ lower than the temperature of the hydrogen and air inlet in the polarization performance test and humidity sensitivity test of the small-sized membrane electrode assembly, the temperature of the stack is T S , the temperature of the hydrogen and air inlet is T IC and T IA , that is, by adjusting T S to be 2-10℃ lower than T IC and T IA , the phenomenon of "over-wetting" in the cell is artificially caused, and the performance of the membrane electrode under the over-wetting condition is evaluated.

2. The test method for evaluating a membrane electrode under simulated wet conditions according to claim 1, wherein Polarization performance testing under excessively humid conditions includes the following steps: 1) Assemble the membrane electrode into a single cell, connect the single cell to the hydrogen and air gas path of the test bench, connect the single cell to the water path of the test bench to control the stack temperature through water temperature, and connect the voltage test clamp. 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) Edit the test plan on the test bench computer and create an "over-humidified" environment by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature; 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and perform analysis.

3. The test method for evaluating a membrane electrode under simulated wet conditions according to claim 2, wherein In step 3), when editing the test plan on the test bench computer, set the parameters according to the following over-humidity polarization curve test, as shown in Figure 8 of the instruction manual.

4. The test method for simulating over-humid conditions evaluation of a membrane electrode according to claim 1, wherein, Humidity sensitivity testing under excessively humid conditions includes the following steps: 1) Assemble the membrane electrode into a single cell, connect the single cell to the hydrogen and air gas path of the test bench, connect the single cell to the water path of the test bench to control the stack temperature through water temperature, and connect the voltage test clamp. 2) Turn on the test bench, complete the fuel cell leak test, and confirm that the fuel cell is connected to the test bench correctly; 3) Edit the test plan on the test bench computer and create "over-humidity" conditions by setting the fuel cell stack temperature to be 2-10°C lower than the inlet air temperature; 4) Run the test program. After the test is completed, follow the steps to purge, cool down, and shut down. 5) Export the data and perform analysis.

5. The test method for simulating the evaluation of a membrane electrode under a humidified condition according to claim 4, wherein In step 3), when editing the test plan on the computer of the test bench, set the humidity sensitivity test parameters according to the following excessive humidity conditions, as shown in Figure 9.

6. The test method for simulating the evaluation of a membrane electrode under a humidified condition according to claim 1, characterized by: Before the test, the operating parameters are input according to the test scheme; during the test, the reaction gas carries water vapor through the pipeline into the cathode / anode flow channel after passing through the humidifier; the temperature of the gas is controlled by the heating belt and the sensor wound on the gas inlet pipeline, that is, the inlet gas temperature T IC and T IA ; the humidity of the gas is determined by the dew point temperature controlled by the humidifier and the inlet gas temperature, that is, T DC and T DA ; the stack temperature is controlled by the stack temperature sensor, the stack heating device and the fan, that is, T S ; by adjusting T S to be 2-10℃ lower than T IC and T IA , an over-humidified environment is formed inside the battery, and the discharge performance of the membrane electrode under this extreme condition is evaluated.

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