Method and device for synchronous detection of multi-zone electrochemical parameters of fuel cell membrane electrode

Abstract

The application discloses a synchronous detection method and device for fuel cell membrane electrode multi-partition electrochemical parameters, and belongs to the technical field of fuel cell parameter detection. The application discloses a synchronous detection method and device for fuel cell membrane electrode multi-partition electrochemical parameters, and belongs to the technical field of fuel cell parameter detection. The application can synchronously realize the detection of electrochemical parameters at different positions of a reaction region, is convenient for determining the performance difference, fault and damage position, aging occurrence region and degree of a fuel cell, and is helpful for guiding the design of key components of the fuel cell and the optimization of a control strategy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cell parameter detection, in particular to a method and device for synchronously detecting multi-zone electrochemical parameters of a fuel cell membrane electrode. BACKGROUND

[0002] The exploitation and utilization of fossil energy have led to an increase in the emission of pollution gases and greenhouse gases, causing global ecological environment deterioration and global warming. Hydrogen energy will be the most important energy in realizing the "carbon peak" and "carbon neutral" goals in China, and proton exchange membrane fuel cells (PEMFC) are the most widely used among hydrogen fuel cells. The basic principle of PEMFC is that hydrogen at the anode and oxygen in the air at the cathode undergo electrochemical reactions to generate pollution-free water, truly achieving "zero emission" of greenhouse gases and pollutants.

[0003] The cost and durability of fuel cells are the two main factors that restrict the commercialization process of fuel cells, and durability is the most important. The active area of commercial proton exchange membrane fuel cells is generally about 300 cm 2 A large reaction area faces greater challenges in reaction gas distribution, water and heat management, and internal state uniformity. Conventional fuel cell test methods (such as polarization curve measurement) can to some extent characterize the overall performance of the fuel cell, but still cannot obtain the real reaction distribution inside the cell, lack local information at different positions, and are difficult to quickly locate the membrane electrode degradation site and diagnose the specific reasons for performance decline. Current density is closely related to the strength of the electrochemical reaction of the fuel cell, and by detecting the distribution of current density on the reaction active area, the local performance of the fuel cell stack in converting chemical energy into electrical energy can be observed.

[0004] Fuel cell operating parameters such as temperature, reaction gas flow, reaction gas relative humidity, reaction gas pressure, and excess coefficient, fuel cell structure design, assembly pressure, and material properties will all affect the dynamic performance of the fuel cell, leading to a decrease in the utilization rate of catalysts and reactants in the active area of the proton exchange membrane fuel cell membrane electrode, and making the electrochemical reaction uneven. The degree of unevenness of the electrochemical reaction of the fuel cell stack membrane electrode affects the energy conversion efficiency of the cell, and areas with severe unevenness will cause local hot spots and lack of gas inside the cell, thereby accelerating the corrosion of the coating of the bipolar plate, local corrosion of the catalyst, and degradation of the membrane, causing cell damage or failure, and greatly reducing the life of the fuel cell. Therefore, when studying the performance of large active area proton exchange membrane fuel cells, it is necessary to fully understand the internal state distribution of the fuel cell during operation.

[0005] Currently, most of the electrochemical parameters based on partition detection only consider alternating current impedance test, and the test process needs to be repeatedly disassembled, ignoring the convenience and synchronization of the test, which greatly increases the test time and accuracy. Therefore, a method based on partition detection device is needed to apply voltage to parallel partitions to synchronously obtain the electrochemical parameters of each partition, so as to realize the rapid detection and rapid fault diagnosis of the electrochemical parameters of different partitions of the fuel cell. SUMMARY

[0006] In order to solve the above problems, the purpose of the present application is to provide a fuel cell membrane electrode multi-partition electrochemical parameter synchronous detection technology based on partition detection device, aiming to realize the synchronous detection of electrochemical parameters at different positions of the reaction area, and to provide data support for determining the performance difference, fault and damage position, aging occurrence area and degree of the fuel cell.

[0007] In order to achieve the above technical purpose, the present application provides a synchronous detection method for fuel cell membrane electrode multi-partition electrochemical parameters, comprising the following steps:

[0008] By means of the partition detection device, the reaction active area is equally divided into small area partitions in parallel, and each small area partition is controlled to be insulated from each other;

[0009] The voltage received by each parallel partition is kept the same, a direct current voltage excitation is adopted to obtain the cyclic direct current voltage excitation response curve and the linear direct current voltage excitation response curve; and an alternating current voltage excitation is adopted to obtain and analyze the alternating current response current curve of each partition, to generate an alternating current impedance curve, and to form the detection result of the fuel cell membrane electrode multi-partition electrochemical parameters by means of the three curves.

[0010] Preferably, in the process of obtaining the cyclic direct current voltage excitation response curve, the fuel cell is subjected to cyclic direct current voltage excitation test, the response current values of different partitions are synchronously collected, the first response current image of different partitions is drawn, and the electrochemical active area and the double-layer capacitance are obtained.

[0011] Preferably, in the process of obtaining the electrochemical active area, a minimum point (x1, y1) is determined near the hydrogen desorption termination voltage, the points with x i less than x1 and y i greater than y1 are integrated to obtain an area A1, and the ratio of A1 to the scanning rate is the hydrogen desorption charge quantity; according to the ratio of the charge quantity corresponding to the single-layer saturated adsorption hydrogen on the smooth platinum catalyst surface to the platinum loading of the catalyst, the electrochemical active area is obtained.

[0012] Preferably, in the process of obtaining the double-layer capacitance, a minimum point (x1, y1) is found near the hydrogen desorption end voltage in the process of voltage increase, a maximum point (x2, y2) is found near the hydrogen adsorption initial voltage in the process of voltage decrease, two straight lines parallel to the abscissa axis are drawn respectively as y=y1 and y=y2, each of the two straight lines has an intersection point with the cyclic direct current voltage excitation response curve, the coordinates of the intersection points are (x3, y1) and (x4, y2) respectively, the area surrounded by the two intersection points and the minimum point (x1, y1) and the maximum point (x2, y2) is integrated to obtain an area A2, the ratio of A2 to the scanning rate is the charge amount carried by the double-layer capacitance of 2 times; x1-x3 and x2-x4 are respectively the voltage change values in the charging and discharging process of the double-layer capacitance, and x1-x3 and x2-x4 are respectively ΔU1 and ΔU2; the double-layer capacitance is obtained according to the ratio of the charge amount carried by the double-layer capacitance of 2 times to the sum of ΔU1 and ΔU2.

[0013] Preferably, in the process of obtaining the linear direct current voltage excitation response curve, the fuel cell is subjected to linear direct current voltage excitation test, the response current values of different partitions are synchronously collected, a plurality of scanning rates are selected for test, the second response current images of different partitions are drawn, and the linear regression method is used to obtain the hydrogen permeation current density and the short-circuit resistance.

[0014] Preferably, in the process of obtaining the hydrogen permeation current density and the short-circuit resistance, the direct current excitation voltage range is set to be between 0 and 1V, a plurality of different scanning rates are selected for measurement within 0-10mV / s, the response current under different scanning rates is subjected to linear regression to obtain the curve at 0mV / s; wherein, a subset is taken for the interval [0.4V, 0.6V], the response current curve corresponding to the subset can be approximately linearly regressed as a straight line, the intercept of the reverse extension line of the straight line on the y-axis is the hydrogen permeation current density, and the reciprocal of the slope is the short-circuit resistance.

[0015] Preferably, in the process of obtaining the alternating current impedance curve, the voltage excitation mode is adopted, the alternating current voltage frequency range is determined based on the characteristics of the fuel cell, the alternating current change of different partitions is synchronously collected for processing, and then the impedance value is obtained.

[0016] Preferably, in the process of obtaining the detection result, the performance difference, the fault and damage position, the aging occurrence area and degree are determined according to the electrochemical active area, the double-layer capacitance, the hydrogen permeation current density, the short-circuit resistance and the impedance value of different partitions, and the detection result is generated.

[0017] The application also discloses a partition detection device for synchronous detection of multi-partition electrochemical parameters of a fuel cell membrane electrode, comprising:

[0018] The partition sampling plate is used for dividing the reaction active area into small-area partitions and insulating each small-area partition from each other.

[0019] a data acquisition unit, which synchronously acquires response current curves of each subzone under the action of voltage;

[0020] a detection result generation unit, which is configured to acquire a direct current voltage excitation response curve and an alternating current impedance curve by using voltage excitation, and generate a detection result of the multi-subzone electrochemical parameters of the fuel cell membrane electrode according to the direct current voltage excitation response curve and the alternating current impedance curve.

[0021] Preferably, the detection result generation unit is further configured to determine performance differences, fault and damage positions, aging occurrence areas and degrees according to the electrochemically active areas, double-layer capacitances, hydrogen permeation current densities and impedance values of different subzones, and generate the detection result.

[0022] The fuel cell is subjected to a cyclic direct current voltage excitation test, and response current values of different subzones are synchronously acquired to draw a first response current image of different subzones and acquire electrochemically active areas and double-layer capacitances.

[0023] The fuel cell is subjected to a linear direct current voltage excitation test, and response current values of different subzones are synchronously acquired to draw a second response current image of different subzones and acquire hydrogen permeation current densities and short-circuit resistances.

[0024] The voltage excitation mode is used, the alternating current voltage frequency range is determined based on the characteristics of the fuel cell, and current change values of different subzones are synchronously acquired to further obtain impedance values.

[0025] The present application discloses the following technical effects:

[0026] The present application can realize synchronous detection of electrochemical parameters at different positions of the reaction area by using the subzone detection device, facilitate determination of performance differences, fault and damage positions, aging occurrence areas and degrees of the fuel cell, and help guide the design of key components of the fuel cell and optimization of control strategies. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0028] Figure 1 is a test flowchart of the present application;

[0029] Figure 2 is a cross-sectional schematic view of the position of the subzone sampling plate in the fuel cell according to the present application;

[0030] Figure 3 is a schematic diagram of a method for calculating the electrochemical active area and double-layer capacitance from a cyclic direct current voltage excitation response curve;

[0031] Figure 4 is a schematic diagram of a method for calculating the hydrogen permeation current density and short-circuit resistance from a linear direct current voltage excitation response curve. DETAILED DESCRIPTION

[0032] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0033] As shown in Figures 1-4 The present application provides a fuel cell membrane electrode multi-partition electrochemical parameter synchronous detection technology. A partition detection device and a signal excitation source are applied. A partition sampling plate of the partition detection device equally divides a reaction active area into small-area partitions with the same area. The signal excitation source applies voltage excitation to the fuel cell. Each partition receives the same voltage excitation. The partition detection device can synchronously collect response current curves of each partition. Through data processing, multi-partition electrochemical parameter test results can be obtained.

[0034] Specifically, the application provides a fuel cell membrane electrode multi-zone electrochemical parameter synchronous detection technology, which adopts a partition detection device and a signal excitation source, a partition collection plate of the partition detection device is placed between a current collection plate and an electrode plate, the partition collection plate divides a reaction active area into small-area partitions, the small-area partitions are insulated from each other, the signal excitation source carries out electrochemical parameter testing on a fuel cell provided with the partition detection device, including cyclic voltammetry testing, linear voltammetry testing and alternating current impedance testing, wherein the cyclic voltammetry testing and the linear voltammetry testing need to apply a direct current voltage excitation to the fuel cell, the voltage excitation of each partition is always the same, the partition detection device synchronously collects response current curves generated by each partition under the action of the voltage, the number of the obtained response current curves is the same as that of the partitions, the response current curves are transmitted to an upper computer for presentation and storage, and electrochemical parameter test results are obtained by data processing on the response current curves. The alternating current impedance testing adopts alternating current voltage excitation, obtains and analyzes alternating current response current curves of each partition, and transmits the alternating current response current curves to the upper computer for processing, and further obtains an alternating current impedance curve.

[0035] The test fuel cell used in the test process mentioned in the application includes an end plate, an insulating plate, a current collection plate, a partition sampling plate, a bipolar plate and a membrane electrode, the partition sampling plate is placed between the current collection plate and the bipolar plate, the experimental device includes a fuel cell test table, a signal excitation source for carrying out electrochemical parameter testing on the fuel cell and an electronic load, a high-frequency data collection device is used for synchronously collecting response current curves obtained by the partition sampling plate, and the response current curves are presented through the upper computer. The partition sampling plate divides a cathode flow field area into multiple independent partitions, and an insulating layer exists between each partition, so that the partitions are not electrically connected.

[0036] The electrochemical parameter detection method mentioned in the application includes cyclic voltammetry testing, linear voltammetry testing and alternating current impedance testing, the signal excitation source needs to apply voltage excitation to the fuel cell, the voltage excitation of each partition on the partition sampling plate is always the same, the partition sampling plate collects response currents, and the response currents are transmitted to the upper computer for saving and displaying response current images of each partition.

[0037] Each partition mentioned in the application above generates a current change curve, a data collector synchronously collects cyclic voltammetry curves, linear voltammetry curves and alternating current impedance curves of each partition, and the number of the collected curves is the same as that of the partitions.

[0038] When the cyclic voltammetry method is used to measure the electrochemical active area and the double-layer capacitance, a direct current excitation voltage range is set as 0-1 V, response current images of different partitions are drawn, an extreme minimum point (x1, y1) of the electrochemical active area needs to be determined near a hydrogen desorption termination voltage, the abscissa x i is less than x1, and the ordinate y iThe area surrounded by points greater than y1 is integrated, and the ratio of the integrated area to the scan rate is the hydrogen desorption charge quantity. The electrochemical active area is the ratio of the charge quantity corresponding to the saturated adsorption of a single layer of hydrogen on the smooth platinum catalyst surface (0.21 mC / cm 2 ) to the platinum loading of the catalyst, and the calculation formula is as shown in formula (1):

[0039]

[0040] In the formula, ECSA represents the electrochemical active area, Q H represents the hydrogen desorption charge quantity, Q m represents the charge quantity corresponding to the saturated adsorption of a single layer of hydrogen on the smooth platinum catalyst surface (0.21 mC / cm 2 ), and L Pt represents the platinum loading.

[0041] In the process of obtaining the double-layer capacitance, a minimum point (x1, y1) is found near the hydrogen desorption termination voltage in the voltage increasing process, and a maximum point (x2, y2) is found near the hydrogen adsorption initial voltage in the voltage decreasing process. Two straight lines parallel to the abscissa axis are drawn, y=y1 and y=y2, respectively. Each straight line has one intersection point with the cyclic voltammetry curve, and the intersection point coordinates are (x3, y1) and (x4, y2), respectively. The area surrounded by the two intersection points and the minimum point (x1, y1) and the maximum point (x2, y2) is integrated to obtain an area A2. The ratio of A2 to the scan rate is the charge quantity carried by the double-layer capacitance of 2 times. x1-x3 and x2-x4 are the voltage change values in the charging and discharging process of the double-layer capacitance, and are denoted as ΔU1 and ΔU2, respectively. The double-layer capacitance is obtained according to the ratio of the charge quantity carried by the double-layer capacitance of 2 times to the sum of ΔU1 and ΔU2, and the calculation formula is as shown in formula (2).

[0042]

[0043] In the formula, Q dl represents the charge quantity carried by the double-layer capacitance of 1 time, and ΔU1 and ΔU2 are the voltage change values in the charging and discharging process of the double-layer capacitance.

[0044] When the linear voltammetry is used to measure the hydrogen permeation current density and the short-circuit resistance, the direct current excitation voltage range is set between 0-1V, a plurality of different scanning rates are selected within 0-10mV / s for measurement, the response current at different scanning rates is linearly regressed to obtain the curve at 0mV / s, the response current curve at the scanning rate of 0mV / s is characterized in that the influence of the double-layer capacitance on the hydrogen permeation current can be eliminated; a subset is taken in the interval [0.4V, 0.6V], the response current curve corresponding to the subset can be linearly regressed as a straight line, the intercept of the reverse extension line of the straight line on the y-axis is the hydrogen permeation current density, and the inverse of the slope is the short-circuit resistance, and the calculation formula is as formula (3):

[0045]

[0046] In the formula, i H is the hydrogen permeation current density, R sc is the short-circuit resistance.

[0047] When the alternating current impedance test is carried out, the alternating current voltage frequency range is determined according to the fuel cell characteristics, the signal excitation source applies the alternating current voltage excitation to obtain the response current curve, and the alternating current impedance curve is obtained through processing and calculation of the voltage and the current.

[0048] In summary, the application further provides a synchronous detection technology for multiple partition electrochemical parameters of a fuel cell membrane electrode, including the following processes:

[0049] Step 1, assembling the fuel cell embedded in the partition sampling plate, connecting the test table and the signal excitation source;

[0050] Step 2, carrying out the cyclic voltammetry test on the fuel cell, the data collector synchronously collects the response current values of different partitions, and the response current images of different partitions are drawn;

[0051] Step 3, carrying out the linear voltammetry test on the fuel cell, the data collector synchronously collects the response current values of different partitions, a plurality of scanning rates are selected for testing, and the response current images of different partitions are drawn;

[0052] Step 4, carrying out the alternating current impedance test on the fuel cell, adopting the voltage excitation mode, the data collector synchronously collects the current change values of different partitions, and the impedance spectrum is obtained through processing in the upper computer and the image is drawn;

[0053] Step 5, obtaining the electrochemical active area, the double-layer capacitance, the hydrogen permeation current density, the short-circuit resistance and the impedance value of different partitions according to the data processing method of formula (1) and formula (2).

[0054] The present application can realize synchronous detection of electrochemical parameters at different positions of the reaction region, facilitate determination of fuel cell performance difference, fault and damage position, aging occurrence region and degree, and help guide key component design of the fuel cell and control strategy optimization.

[0055] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system), and computer program product according to embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, as well as a combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing apparatus generate a means for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus with the function specified in one or more flows or blocks.

[0056] In the description of the present application, it should be understood that the terms "first", "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0057] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A method for simultaneous detection of multi-zone electrochemical parameters of a fuel cell membrane electrode, characterized in that, Includes the following steps: The reactive region is divided into small areas, and the small areas are kept insulated from each other. The voltage excitation of each zone is kept the same. DC voltage excitation is used to obtain the DC voltage excitation response curve of each zone. AC voltage excitation is used to obtain and analyze the AC response current curve of each zone to generate the AC impedance curve. Based on the DC voltage excitation response curve and the AC impedance curve, the detection results of the multi-zone electrochemical parameters of the fuel cell membrane electrode are generated. In the process of acquiring the DC voltage excitation response curve, the DC voltage excitation response curve is generated by collecting the cyclic DC voltage excitation response curve and the linear DC voltage excitation response curve of each partition. In the process of obtaining the cyclic DC voltage excitation response curve, the fuel cell is subjected to cyclic DC voltage excitation test, and the response current values ​​of different zones are collected simultaneously. The first response current image of different zones is plotted to obtain the electrochemical active area and double layer capacitance. In the process of obtaining the linear DC voltage excitation response curve, the linear DC voltage excitation synchronously collects the response current values ​​of different partitions, selects multiple scan rates for testing, plots the second response current image of different partitions, and uses the linear regression method to obtain the hydrogen permeation current density and short-circuit resistance. In obtaining the hydrogen permeation current density and short-circuit resistance, the DC excitation voltage range is set between 0 and 1V. Multiple different scan rates are selected within the range of 0-10mV / s for measurement. By performing linear regression on the response current at different scan rates, the curve at 0mV / s is obtained. Among them, a subset is taken from the interval [0.4V, 0.6V]. The response current curve corresponding to the subset can be approximately linearly regressed to a straight line. The intercept of the reverse extension of this straight line on the y-axis is the hydrogen permeation current density, and the reciprocal of the slope is the short-circuit resistance.

2. The method for simultaneous detection of multi-zone electrochemical parameters of fuel cell membrane electrode according to claim 1, characterized in that: In obtaining the electrochemical active area, a minimum point (x1, y1) is determined near the hydrogen desorption termination voltage. The x-axis is then compared with the minimum point (x1, y1). i Less than x1, y-coordinate i The area enclosed by points greater than y1 is integrated, and the ratio of the integrated area to the scan rate is the amount of hydrogen desorption charge; the electrochemical active area is obtained based on the ratio of the charge corresponding to the monolayer saturated adsorption of hydrogen on the surface of the smooth platinum catalyst to the platinum loading of the catalyst. In obtaining the electric double-layer capacitance, the minimum point (x1, y1) is found near the hydrogen desorption termination voltage during the voltage increase process, and the maximum point (x2, y2) is found near the hydrogen adsorption initial voltage during the voltage decrease process. Two straight lines, y = y1 and y = y2, are drawn parallel to the horizontal axis. Each straight line intersects the cyclic DC voltage excitation response curve at one point, with the coordinates of the intersection points being (x3, y1) and (x4, y2), respectively. The area A2 is obtained by integrating the area enclosed by the two intersection points and the minimum point (x1, y1) and the maximum point (x2, y2). The ratio of A2 to the scan rate is twice the charge carried by the electric double-layer capacitance. x1-x3 and x2-x4 are the voltage changes during the charging and discharging process of the electric double-layer capacitance, and x1-x3 and x2-x4 are denoted as ΔU1 and ΔU2, respectively. The electric double-layer capacitance is obtained based on the ratio of twice the charge carried by the electric double-layer capacitance to the sum of ΔU1 and ΔU2.

3. The method for simultaneous detection of multi-zone electrochemical parameters of fuel cell membrane electrode according to claim 1, characterized in that: In the process of obtaining the AC impedance curve, a voltage excitation mode is adopted. The AC voltage frequency range is determined based on the characteristics of the fuel cell, and the AC current of different zones is collected simultaneously to obtain the impedance value.

4. The method for simultaneous detection of multi-zone electrochemical parameters of fuel cell membrane electrode according to claim 1, characterized in that: In the process of obtaining test results, the performance differences, fault and damage locations, aging areas and degrees are determined based on the electrochemical active area, double layer capacitance, hydrogen permeation current density, short-circuit resistance and impedance values ​​of different zones, and the test results are generated.

5. A device for synchronous detection of multi-zone electrochemical parameters of a fuel cell membrane electrode assembly, used to implement the method for synchronous detection of multi-zone electrochemical parameters of a fuel cell membrane electrode assembly as described in claim 1, characterized in that, include: The partitioning unit of the partition detection device is used to divide the reactive region into small areas and control the insulation between the small areas. The data acquisition unit synchronously acquires the response current curves of each partition under voltage. The detection result generation unit is used to obtain a DC voltage excitation response curve and generate an AC impedance curve using voltage excitation, and to generate detection results of multi-zone electrochemical parameters of the fuel cell membrane electrode based on the DC voltage excitation response curve and the AC impedance curve.

6. The synchronous detection device for multi-zone electrochemical parameters of fuel cell membrane electrode according to claim 5, characterized in that: The detection result generation unit is also used to determine performance differences, fault and damage locations, and aging areas and degrees based on the electrochemical active area, double-layer capacitance, hydrogen permeation current density, short-circuit resistance, and impedance values ​​of different zones, and to generate the detection results. Cyclic DC voltage excitation tests were conducted on the fuel cell, and the response current values ​​of different zones were collected simultaneously. The first response current images of different zones were plotted to obtain the electrochemical active area and double-layer capacitance. Linear DC voltage excitation tests were conducted on the fuel cell, and the response current values ​​of different zones were collected simultaneously. Multiple scan rates were selected for testing, and second response current images of different zones were plotted. The hydrogen permeation current density and short-circuit resistance were obtained by linear regression. Using a voltage excitation mode, the AC voltage frequency range is determined based on the characteristics of the fuel cell, and the AC current of different zones is collected synchronously to obtain the impedance value.

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