Quality detection method and device for bipolar plate of fuel cell, storage medium and vehicle

Abstract

The invention relates to the technical field of fuel cells, and particularly discloses a quality detection method and device of a fuel cell bipolar plate, a storage medium and a vehicle, and the quality detection method of the fuel cell bipolar plate comprises the following steps: obtaining a failure criterion and a plurality of acceleration variables of the fuel cell bipolar plate, taking the failure criterion as a failure parameter of the bipolar plate of the fuel cell, determining a failure parameter corresponding to each acceleration variable by adopting a control variable method and a preset model, and determining a total acceleration factor according to a coupling coefficient of the failure parameter and the acceleration factor, and obtaining the test duration for the fuel cell bipolar plate to reach the failure parameter under the plurality of preset acceleration variables and the actual acceleration variable of the fuel cell bipolar plate, and finally determining the real-time life of the fuel cell bipolar plate according to the plurality of preset acceleration variables, the test duration, the actual acceleration variable and the total acceleration factor, thereby realizing high-precision quality prediction.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a method and apparatus for quality testing of fuel cell bipolar plates, a storage medium, and a vehicle. Background Technology

[0002] As a key representative of clean energy transportation, fuel cell vehicles are gradually becoming a crucial direction for the transformation of the global automotive industry. Although their strategic significance has gained global consensus, they still face challenges related to cost and durability. Proton exchange membrane fuel cells (PEMFCs), with their advantages of high energy conversion efficiency and rapid start-up, are currently the only type of fuel cell used in fuel cell vehicles.

[0003] Bipolar plates account for approximately 25-30% of the total cost and 70% of the total volume of a PEMFC stack. The metal bipolar plate coating of the fuel cell is responsible for the lifespan indicators of the stack and bipolar plates, and is coupled with the membrane electrode assembly, jointly limiting the working life of the fuel cell. For fuel cells used in vehicles, the lifespan should at least reach the level of an internal combustion engine, that is, the fuel cell lifespan should meet at least 8,000 hours (15 years, 300,000 kilometers).

[0004] Currently, most corrosion resistance evaluation methods define potential, temperature, and corrosion ion concentration as specific values, without systematically establishing their relationship with actual vehicle operating conditions, and the rationality of these values ​​is unknown. Summary of the Invention

[0005] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to propose a quality inspection method for fuel cell bipolar plates, which can map failure data under accelerated conditions to the actual operating conditions of the fuel cell through a scientific model, achieving high-precision quality prediction.

[0006] A second objective of this invention is to provide a computer-readable storage medium.

[0007] The third objective of this invention is to provide a quality testing device for fuel cell bipolar plates.

[0008] The fourth objective of this invention is to provide a vehicle.

[0009] To achieve the above objectives, a first aspect of the present invention provides a quality inspection method for a fuel cell bipolar plate. The method includes: acquiring a failure criterion and multiple acceleration variables for the fuel cell bipolar plate; using the failure criterion as a failure parameter of the fuel cell bipolar plate, and employing a control variable method and a preset model to determine the acceleration parameters for failure of the fuel cell bipolar plate under the multiple acceleration variables; acquiring the coupling coefficient of the total acceleration factor of the fuel cell bipolar plate; determining the total acceleration factor based on the acceleration parameters and the coupling coefficient; acquiring the test duration for the fuel cell bipolar plate to reach the failure parameters under the preset multiple acceleration variables and the actual acceleration variables of the fuel cell bipolar plate; and determining the real-time lifetime of the fuel cell bipolar plate based on the preset multiple acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor.

[0010] In the quality inspection method for fuel cell bipolar plates in this invention, the failure criteria and multiple acceleration variables of the fuel cell bipolar plate are first obtained. Then, the failure criteria are used as the failure parameters of the fuel cell bipolar plate. Next, the failure parameters corresponding to each acceleration variable are determined by the control variable method and a preset model. Then, the total acceleration factor is determined based on the coupling coefficient between the failure parameters and the acceleration factor. After that, the test time for the fuel cell bipolar plate to reach the failure parameters under multiple preset acceleration variables and the actual acceleration variables of the fuel cell bipolar plate are obtained. Finally, the real-time life of the fuel cell bipolar plate is determined based on the multiple preset acceleration variables, the test time, the actual acceleration variables, and the total acceleration factor. Thus, the failure data under acceleration conditions can be mapped to the actual operating conditions of the fuel cell through a scientific model, achieving high-precision quality prediction.

[0011] In some embodiments of the present invention, the method further includes: preparing a sulfuric acid aqueous solution with pH=3 containing 1 ppm fluoride ions, and heating the sulfuric acid aqueous solution to 80°C using a water bath and maintaining the temperature stable; setting the reference electrode as an Ag / AgCl (saturated KCl) electrode and the counter electrode as a platinum sheet electrode; connecting the electrode to be tested to the working electrode, and using potentiodynamic polarization method to scan from 0 to 1V vs. RHE at a scan rate of 1mV / s to obtain a polarization curve, plotting it, and then determining the failure criterion by using the ordinate of the intersection point of the Tafel lines in the plot based on the polarization curve.

[0012] In some embodiments of the present invention, the plurality of acceleration variables include the concentration of fluoride-containing sulfuric acid aqueous solution, temperature parameters, and voltage parameters.

[0013] In some embodiments of the present invention, when the accelerating variable is the concentration of sulfuric acid aqueous solution containing fluoride ions or a voltage parameter, the preset model is determined to be the Peck model or the inverse power law model; when the accelerating variable is a temperature parameter, the preset model is determined to be the Arrhenius model.

[0014] In some embodiments of the present invention, the method further includes: determining a first acceleration factor of the fuel cell bipolar plate in the concentration of the sulfuric acid aqueous solution containing fluoride ions and a second acceleration factor in the voltage parameter using the inverse power law model, and determining a third acceleration factor of the fuel cell bipolar plate in the temperature parameter using the Arrhenius model; multiplying the first acceleration factor, the second acceleration factor, the third acceleration factor and the coupling coefficient to determine the total acceleration factor.

[0015] In some embodiments of the present invention, the method further includes: obtaining multiple sets of acceleration variables and multiple sets of durations corresponding to the time when the fuel cell bipolar plate reaches the failure parameter under the multiple sets of acceleration variables; and determining the coupling coefficient based on the multiple sets of acceleration variables and the multiple sets of durations.

[0016] In some embodiments of the present invention, the total acceleration factor is equal to the ratio of the actual usage time of the fuel cell bipolar plate to the test time.

[0017] To achieve the above objectives, a second aspect of the present invention provides a computer-readable storage medium storing a quality inspection program for a fuel cell bipolar plate, wherein when the quality inspection program is executed by a processor, it implements the quality inspection method for a fuel cell bipolar plate as described in any of the above embodiments.

[0018] The computer-readable storage medium of this invention executes a quality detection program for fuel cell bipolar plates stored thereon via a processor. This program can map failure data under accelerated conditions to the actual operating conditions of the fuel cell using a scientific model, thereby achieving high-precision quality prediction.

[0019] To achieve the above objectives, a third aspect of the present invention provides a quality testing device for a fuel cell bipolar plate. The device includes: an acquisition module for acquiring a failure criterion and multiple acceleration variables for the fuel cell bipolar plate; a determination module for using the failure criterion as a failure parameter of the fuel cell bipolar plate, and employing a control variable method and a preset model to determine the acceleration parameters for failure of the fuel cell bipolar plate under the multiple acceleration variables; the acquisition module is further configured to acquire a coupling coefficient of the total acceleration factor of the fuel cell bipolar plate; the determination module is further configured to determine the total acceleration factor based on the acceleration parameters and the coupling coefficient; the acquisition module is further configured to acquire the test duration for the fuel cell bipolar plate to reach the failure parameters under the preset multiple acceleration variables, and the actual acceleration variables of the fuel cell bipolar plate; the determination module is further configured to determine the real-time lifetime of the fuel cell bipolar plate based on the preset multiple acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor.

[0020] The quality detection device for fuel cell bipolar plates in this invention includes an acquisition module and a determination module. First, the acquisition module acquires the failure criteria and multiple acceleration variables of the fuel cell bipolar plate. Then, the determination module uses the failure criteria as the failure parameters of the fuel cell bipolar plate, and then uses the control variable method and a preset model to determine the failure parameters corresponding to each acceleration variable. Next, the determination module determines the total acceleration factor based on the coupling coefficient of the failure parameters and the acceleration factor acquired by the acquisition module. After that, the acquisition module acquires the test duration for the fuel cell bipolar plate to reach the failure parameters under multiple preset acceleration variables and the actual acceleration variables of the fuel cell bipolar plate. Finally, the determination module determines the real-time lifespan of the fuel cell bipolar plate based on the multiple preset acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor. Thus, it is possible to map the failure data under acceleration conditions to the actual operating conditions of the fuel cell through a scientific model, thereby achieving high-precision quality prediction.

[0021] To achieve the above objectives, a fourth aspect of the present invention provides a vehicle comprising a fuel cell and a quality inspection device for the fuel cell bipolar plate described in the above embodiments, the quality inspection device for the fuel cell bipolar plate being used to perform quality inspection on the bipolar plate of the fuel cell.

[0022] The vehicle in this embodiment of the invention, through the quality detection device for the fuel cell bipolar plate described above, can map failure data under acceleration conditions to the actual operating conditions of the fuel cell using a scientific model, thereby achieving high-precision quality prediction.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] Figure 1 This is a flowchart of a quality inspection method for fuel cell bipolar plates in one embodiment of the present invention; Figure 2 This is a flowchart of a quality inspection method for fuel cell bipolar plates in another embodiment of the present invention; Figure 3 This is a flowchart of a quality inspection method for fuel cell bipolar plates in another embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the determination of failure criteria in one embodiment of the present invention; Figure 5 This is a schematic diagram of the fitting data for the constant term in the voltage parameter acceleration formula in one embodiment of the present invention; Figure 6 This is a schematic diagram of the fitting data for the constant term in the temperature parameter acceleration formula in one embodiment of the present invention; Figure 7This is a schematic diagram of the fitting data for the constant term in the fluoride ion concentration acceleration formula in one embodiment of the present invention; Figure 8 This is a schematic diagram of the partial average cell voltage of a fuel cell engine in a specific embodiment of the present invention; Figure 9 This is a schematic diagram of the coolant outlet temperature of a fuel cell engine in a specific embodiment of the present invention; Figure 10 This is a schematic diagram of the self-corrosion current density of the fuel cell electrode plate after a vehicle test in a specific embodiment of the present invention; Figure 11 This is a schematic diagram of the self-corrosion current density of a fuel cell after an accelerated life test in a specific embodiment of the present invention; Figure 12 This is a block diagram of the quality detection device for fuel cell bipolar plates in an embodiment of the present invention; Figure 13 This is a schematic diagram of a vehicle according to an embodiment of the present invention. Detailed Implementation

[0025] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0026] The following description, with reference to the accompanying drawings, outlines a method and apparatus for quality testing of fuel cell bipolar plates, a storage medium, and a vehicle according to embodiments of the present invention.

[0027] Figure 1 This is a flowchart of a quality inspection method for fuel cell bipolar plates in one embodiment of the present invention.

[0028] like Figure 1 As shown, this invention proposes a quality inspection method for fuel cell bipolar plates, which includes the following steps: S10: Obtain the failure criteria for the bipolar plate of the fuel cell and multiple acceleration variables.

[0029] Specifically, the failure criterion in this embodiment can be defined as the electrode self-corrosion current density when the actual durability of the fuel cell engine / stack decreases by 10% under normal operating conditions. I corr_end Multiple accelerating variables can include the concentration of fluoride-containing sulfuric acid aqueous solution, temperature parameters, and voltage parameters. It should be noted that accelerating variables can also include other variables, specifically those that can affect the failure of the fuel cell bipolar plates. Understandably, more accelerating variables result in higher detection accuracy but slower detection speed; the specific number of accelerating variables can be determined based on actual requirements.

[0030] In some embodiments of the present invention, the quality testing method for fuel cell bipolar plates further includes: preparing a sulfuric acid aqueous solution with pH=3 containing 1 ppm fluoride ions, and heating the sulfuric acid aqueous solution to 80°C using a water bath and maintaining the temperature stable; setting the reference electrode as an Ag / AgCl (saturated KCl) electrode and the counter electrode as a platinum sheet electrode; connecting the electrode to be tested to the working electrode, and using potentiodynamic polarization method to scan from 0 to 1V vs. RHE at a scan rate of 1mV / s to obtain a polarization curve, plotting it, and then determining the failure criterion by using the ordinate of the intersection point of the Tafel lines in the graph based on the polarization curve.

[0031] Specifically, first, a sulfuric acid aqueous solution with pH=3 containing 1 ppm fluoride ions was prepared and heated to 80°C using a water bath, maintaining a stable temperature. An Ag / AgCl (saturated KCl) electrode was used as the reference electrode, and a platinum sheet electrode was used as the counter electrode. The electrode to be tested was connected to the working electrode, the platinum sheet electrode to the counter electrode, and the Ag / AgCl (saturated KCl) electrode to the reference electrode. The electrochemical workstation was then turned on. Potentiodynamic polarization was used, scanning from 0 to 1 V vs. RHE at a scan rate of 1 mV / s. The obtained polarization curves were then plotted, as shown below. Figure 4 As shown, the ordinate of the intersection point of the Tafel lines is 2.97 μA / cm. 2 As a criterion for invalidation I corr_end .

[0032] S20 uses the failure criteria as the failure parameters of the fuel cell bipolar plate, and uses the control variable method and preset model to determine the acceleration parameters of the fuel cell bipolar plate failure under multiple acceleration variables.

[0033] Specifically, this embodiment uses self-corrosion current density I corr_end As the parameter for life termination in single-stress tests, controlled variable experiments are conducted, with other conditions using mild values ​​that do not affect electrode failure, to ensure the accuracy of the single factor and obtain the constant terms of each single-stress acceleration formula. For example, the concentration of fluoride-containing sulfuric acid aqueous solution can be chosen as the variable, while temperature and voltage parameters use values ​​that do not affect electrode failure. This determines the constant term of the fluoride-containing sulfuric acid aqueous solution solubility acceleration formula, and similarly determines the constant terms of the acceleration formulas corresponding to temperature and voltage parameters. When the acceleration variable is the concentration of fluoride-containing sulfuric acid aqueous solution or voltage parameter, the preset model is determined to be the Peck model or the inverse power law model; when the acceleration variable is the temperature parameter, the preset model is determined to be the Arrhenius model. See also Figure 5 , Figure 6 and Figure 7 ,in, Figure 5This is a schematic diagram of the fitting data for the constant term in the voltage parameter acceleration formula in one embodiment of the present invention. Figure 6 This is a schematic diagram of the fitting data for the constant term in the temperature parameter acceleration formula in one embodiment of the present invention. Figure 7 This is a schematic diagram of the fitting data for the constant term in the fluoride ion concentration acceleration formula in one embodiment of the present invention.

[0034] S30, obtain the coupling coefficient of the total acceleration factor of the fuel cell bipolar plate.

[0035] Specifically, the single-stress acceleration formula is multiplied together, and a coupling coefficient is added as a correction factor for the single-stress acceleration factor to ensure the accuracy of coupling between the acceleration variables. In some embodiments, multiple sets of acceleration variables and multiple sets of times corresponding to the fuel cell bipolar plate reaching the failure parameters under multiple sets of acceleration variables can be obtained; the coupling coefficient is determined based on the multiple sets of acceleration variables and multiple sets of times.

[0036] S40 determines the total acceleration factor based on acceleration parameters and coupling coefficients.

[0037] Specifically, three sets of experimental data can be taken, and correction coefficients for voltage parameters, temperature parameters, and the concentration of fluoride ion sulfuric acid aqueous solution can be fitted to obtain the formula for the total acceleration factor AF. It should be noted that the total acceleration factor is equal to the ratio of the actual usage time of the fuel cell bipolar plate to the test time. In some embodiments, the first acceleration factor of the fuel cell bipolar plate in the concentration of fluoride ion sulfuric acid aqueous solution and the second acceleration factor in the voltage parameter are determined by an inverse power law model, and the third acceleration factor of the fuel cell bipolar plate in the temperature parameter is determined by an Arrhenius model; the first acceleration factor, the second acceleration factor, the third acceleration factor, and the coupling coefficient are multiplied together to determine the total acceleration factor.

[0038] More specifically, voltage parameters are accelerated using an inverse power-law model. (t is the failure time, Kv and a are constants related to the product type) The test method is as follows: at room temperature, the electrolyte is a sulfuric acid solution with pH=3. Using the constant potential method, at least two sets of data are measured until failure. Taking the logarithm of both sides of the above equation, we get lnt=-lnKv-alnV. Plotting lnt and lnV as a straight line, we obtain the material-related parameter a. Then, according to... Vuse is the actual operating voltage, and Vtest is the test voltage. Acceleration factors are obtained under different operating and test voltages. The test potential range is 0.2~1.2V vs. RHE, with 0.5V, 0.7V, and 0.9V being preferred. Temperature acceleration is achieved using the Arrhenius model, k... (k is the failure reaction rate, A and Ea are constants related to product type, Ea is the activation energy, e is the base of the natural logarithm 2.71828, and R is the gas constant 8.314 J / mol·K). The test method is as follows: place the coating sample in a sulfuric acid solution containing 1 ppm F- and pH=3, and measure at a constant potential of 0.5V. After measuring at least two sets of data, the electrochemical self-corrosion current density is measured as the failure reaction rate k. Taking the logarithm of both sides of the above equation yields... , with lnk and Plot a straight line to calculate the apparent activation energy Ea, and then according to... kB is the Boltzmann constant, 8.617 x 10⁻⁶. -5 The acceleration factor was obtained at different operating and testing temperatures (eV / K), with a test temperature range of 25–90 °C, preferably 60 °C, 70 °C, and 80 °C. For corrosion ions (i.e., fluoride ions in sulfuric acid aqueous solution), a modified Peck model or an inverse power-law model was used to accelerate the process, with the inverse power-law model preferred. t is the failure time, Kc and b are constants related to the product type. The test method is as follows: at room temperature, the coating sample is placed in a sulfuric acid aqueous solution containing F- and pH=3, and measured at a constant potential of 0.5 V. At least two sets of data are measured until failure. Taking the logarithm of both sides of the above equation yields lnt=-lnKc-blnC. Plotting lnt and lnC as a straight line, the material-related parameters Kc and b are calculated. Then, according to... The acceleration factor was determined under different usage and test corrosion ion concentrations, with the F- range being 1~15 ppm, preferably 1ppm, 3ppm, and 5ppm.

[0039] Extract the individual acceleration conditions (Vuse, Tu, and cuse) from the engine used in the failure criterion test as the actual operating conditions. Set up another set of accelerated stress tests with stresses higher than Vuse, Tu, and cuse. Test until failure. The total acceleration factor is calculated using a multiplication method: AF = ,in The correction factor is related to cyclic load variation, and the relationship between the total acceleration factor and acceleration conditions and operating conditions is obtained.

[0040] S50: Obtain the test duration for the fuel cell bipolar plate to reach the failure parameters under multiple preset acceleration variables, and the actual acceleration variables of the fuel cell bipolar plate.

[0041] S60 determines the real-time lifespan of the fuel cell bipolar plate based on multiple preset acceleration variables, test duration, actual acceleration variables, and total acceleration factor.

[0042] Specifically, by extracting the vehicle voltage spectrum and coolant outlet temperature spectrum, and statistically analyzing the voltage and temperature distribution ranges as actual operating conditions, the stress severity is increased based on these conditions. After determining the target operating time, the formula is used... This yields the equivalent test time for accelerated lifespan; by setting the voltage, temperature, and corrosion ion concentration in the experiment, the test continues until failure, and the failure time is recorded. t test ; Monitor the average cell voltage of vehicles V use Operating temperature T use The concentration of the fluoride ion-containing sulfuric acid aqueous solution is the same as the experimental concentration. Substituting this into the total acceleration factor formula, the AF is calculated, and the real-time predicted lifetime is obtained. t use =AF× t test This allows for the acquisition of the real-time health status of the electrode plates. It should be noted that the specific implementation details of this embodiment can also be found in [reference needed]. Figure 2 and Figure 3 The flowchart shown.

[0043] In one specific embodiment of the present invention, the method for quality detection of fuel cell bipolar plates includes the following steps: The first step is to determine the failure criteria.

[0044] Specifically, with self-corrosion current density I corr_end (Corresponding to a 10% degradation in stack durability) is the failure endpoint. After each test, a potentiodynamic scanning method is used to obtain the self-corrosion current density to determine whether this threshold has been reached. I corr_end The fuel cell engine was operated normally according to its operating condition spectrum. When the rated polarization performance dropped to 10%, the stack was disassembled to obtain the electrode material. The area with the most severe visual discoloration was selected from the entire plate, cut into 15mm circular samples, and the edges were flattened before being inserted into a container with an exposed area of ​​1 cm². 2 The electrode clamps were tightened to ensure no liquid seepage from the edges. A pH 3 sulfuric acid aqueous solution containing 1 ppm fluoride ions was prepared, heated to 80°C using a water bath and maintained at a stable temperature. An Ag / AgCl (saturated KCl) electrode was used as the reference electrode, and a platinum sheet electrode was used as the counter electrode. The electrode clamp was connected to the working electrode, the platinum sheet electrode to the counter electrode, and the Ag / AgCl (saturated KCl) electrode to the reference electrode. The electrochemical workstation was turned on. Potentiodynamic polarization was used, scanning from 0 to 1 V vs. RHE at a scan rate of 1 mV / s. The polarization curves were obtained and plotted. The ordinate of the intersection of the Tafel lines was set to 2.97 μA / cm. 2 As a criterion for invalidation I corr_end .

[0045] The second step is to select the acceleration variable.

[0046] Voltage parameters, temperature parameters, and F -Concentration is defined as an accelerating variable.

[0047] The third step is to conduct single-stress tests and determine the constants of the acceleration formula.

[0048] Specifically, when the accelerating variable is the voltage parameter, an inverse power law model is used to determine the constant term of the acceleration formula. First, the experimental conditions are determined: room temperature, sulfuric acid aqueous solution with pH=3 as the electrolyte, and the potentiostatic method. The potential test points are determined to be 0.9V vs. RHE and 1.1V vs. RHE. Tests are conducted at potentials of 0.9V and 1.1V until failure, and the time t is recorded. The method is as follows: when a potential change is observed, the electrode is removed, rinsed with deionized water, and placed in the electrolyte in S1. The self-corrosion current density is measured. If it is less than the failure criterion, it is returned to continue the potentiostatic acceleration test until it equals the failure criterion, and the failure time t is recorded. Based on lnt=-lnK... v -alnV, draw a straight line with lnt and lnV, and obtain the parameter a as 2.2 based on the slope.

[0049] When the accelerating variable is temperature, the Arrhenius model is used to determine the constant term of the acceleration formula. First, the experimental conditions are determined: the electrolyte is a sulfuric acid aqueous solution containing 1 ppm fluoride ions, pH=3, and the method is a 0.5V constant potential method. The temperature test points are determined to be 60℃ (333K) and 80℃ (353K). Tests are conducted at 60℃ and 80℃ until failure, and the time t is recorded. The method is as follows: when a potential change is observed, the electrode is removed, rinsed with deionized water, and then placed in the sulfuric acid aqueous solution prepared in the first step. The self-corrosion current density is measured. If it is less than the failure criterion, it is returned to continue the constant potential acceleration test until it equals the failure criterion, and the failure time t is recorded. , with lnk and Draw a straight line and obtain the parameters from the slope. It is 0.4 eV. When the accelerating variable is the concentration of corrosion ions, an inverse power-law model is used to determine the constant term of the acceleration formula. First, the test conditions are determined: room temperature, sulfuric acid aqueous solution with pH=3, and a 0.5V potentiostatic method. The fluoride ion concentration test points are set at 7ppm and 10ppm. Tests are conducted at 7ppm and 10ppm respectively until failure, and the time t is recorded. The method is as follows: when a potential change is observed, the electrode is removed, rinsed with deionized water, and then placed in the sulfuric acid solution prepared in the first step. The self-corrosion current density is measured. If it is less than the failure criterion, it is returned to continue the potentiostatic acceleration test until it equals the failure criterion, and the failure time t is recorded. lnt = -lnK c -blnC, draw a straight line with lnt and lnC, and obtain the parameter b as 1.2 based on the slope.

[0050] The fourth step is to determine the formula for calculating the total acceleration factor.

[0051] The formula for calculating the total acceleration factor is AF= .

[0052] The fifth step is to determine the total acceleration factor correction coefficient and formula.

[0053] Select voltage parameters, temperature parameters, and F. - Three acceleration parameters were used for concentration testing, with values ​​of 0.9V, 90℃, and 3ppm (all within the actual range of the engine's failure criteria, corresponding to startup). The test duration to failure was 18 hours, resulting in a total acceleration factor AF of 1000 / 18 = 55.6. Then, values ​​of 1.0V, 90℃, and 5ppm were used, with a test duration to failure of 12 hours, resulting in an acceleration factor AF of 1000 / 12 = 83.3. Substituting the two sets of data into the formula AF = ... The calculated coupling coefficient α is 0.83, and AF = .

[0054] Step 6: Determine the experimental plan.

[0055] Extracting partial average cell voltage spectra and coolant outlet temperature spectra of fuel cell engines from the WLTC (World Light-duty Vehicle Test Cycle) test of a whole vehicle, as shown below. Figure 8 and Figure 9 As shown in the table below, the statistical distribution of voltage and coolant temperature varies with power. - Defined as 1 ppm:

[0056] The accelerated testing conditions were determined to be 1.0V, 90℃, and 3ppmF. - Substitute the three sets of data in the table and the determined accelerated test conditions into the overall acceleration formula AF= obtained in step five. In the interval range, the median value was taken, resulting in three acceleration factors AF: 7.96, 8.74, and 7.10. To verify the acceleration conditions, the planned usage time t was... use If the driving range is set to 9.2 hours, then the acceleration conditions are as follows (1.0 V, 75℃, 3 ppm F). - The test and time interval ratios are as follows: the three intervals require 43 minutes, 4.7 minutes and 23.7 minutes of testing respectively, totaling 1.19 hours, which is equivalent to an actual test of 9.2 hours.

[0057] The actual test duration was set at 9.2 hours. The self-corrosion current density was measured. The fuel cell engine stack from step six was disassembled to obtain the electrode material. The electrode was cut into 15mm circular samples, the edges were flattened, and then inserted into a 1cm² exposed area. 2The electrode clamps were tightened to ensure no liquid seeped in from the edges. A pH=3 sulfuric acid aqueous solution containing 1 ppm fluoride ions was prepared, heated to 80°C in a water bath and maintained at a stable temperature. Using potentiodynamic polarization, the sample was scanned from 0 to 1V vs. RHE at a scan rate of 1 mV / s. The obtained polarization curves were plotted, and the ordinate of the intersection of the Tafel lines was set to 0.142 μA / cm. 2 ,like Figure 10 As shown.

[0058] To verify the above actual test, brand new electrode material from the same manufacturer was taken, and the electrode was cut into 15mm circular samples. After the edges were flattened, the samples were inserted into a container with an exposed area of ​​1cm². 2 The electrode clamps were tightened to ensure no liquid seepage from the edges. A pH=3 sulfuric acid aqueous solution containing 3 ppm fluoride ions was prepared, heated to 90°C in a water bath and maintained at a stable temperature. An Ag / AgCl (saturated KCl) electrode was used as the reference electrode, and a platinum sheet electrode was used as the counter electrode. The electrode clamp was connected to the working electrode, the platinum sheet electrode to the counter electrode, and the Ag / AgCl (saturated KCl) to the reference electrode. The electrochemical workstation was turned on and run at a constant potential of 1.0 V for 1.19 hours. After accelerated testing, the self-corrosion current density was measured: After cleaning the electrodes, a pH=3 sulfuric acid aqueous solution containing 1 ppm fluoride ions was prepared, heated to 80°C in a water bath and maintained at a stable temperature. Potentiodynamic polarization was used, scanning from 0 to 1V vs. RHE at a scan rate of 1 mV / s. The obtained polarization curves were plotted, and the ordinate of the intersection of the Tafel lines was set to 0.145 μA / cm. 2 ,like Figure 11 As shown, the actual result is 0.142 μA / cm. 2 Within the allowable error range (≤0.005μA / cm) 2 The fact that the values ​​are close indicates that this acceleration method is effective.

[0059] To apply the above method to real-time vehicle monitoring, the voltage, temperature, and fluoride ion concentration were first set at 1.2V, 90℃, and 3ppm in the laboratory, accelerating the process to failure. The specific method is as follows: Take brand-new electrode material from the same manufacturer, cut the electrode into 15mm circular samples, flatten the edges, and insert them into a container with an exposed area of ​​1cm². 2 Tighten the electrode clamps to ensure no liquid seeps in from the edges. Prepare a pH 3 sulfuric acid aqueous solution containing 3 ppm fluoride ions, heat it to 90°C using a water bath and maintain a stable temperature. Use an Ag / AgCl (saturated KCl) electrode as the reference electrode and a platinum sheet electrode as the counter electrode. Connect the electrode clamp to the working electrode, the platinum sheet electrode to the counter electrode, and the Ag / AgCl (saturated KCl) electrode to the reference electrode. Turn on the electrochemical workstation. Run it at a constant potential of 1.2V until failure, and record the failure time t. test For 2000 hours, monitor the average cell voltage V of the vehicle.use Use temperature T u Since the F- concentration could not be monitored, it was kept the same as the experimental concentration (3 ppm). The real-time value was substituted into the total acceleration factor formula AF = AF is calculated in real time to obtain the real-time lifetime t. use =AF×t test This allows us to obtain the health status of the electrode plates during vehicle operation.

[0060] In summary, the fuel cell bipolar plate quality inspection method of this invention combines the actual permissible operating conditions of the vehicle with the failure mechanism of the metal bipolar plate coating of the proton exchange membrane fuel cell. Based on a reliability physical empirical model, a multi-stress coupled quality inspection scheme is designed, using electrochemical potential, temperature, and corrosion ion concentration as accelerating stresses. By correlating the accelerating environment with the actual operating conditions of the vehicle through a physical model, quantitative prediction of coating life is achieved. Its core is to map failure data under accelerated conditions to the actual operating conditions of the vehicle through a scientific model, achieving high-precision life prediction. The technical solution and method adopted in this invention are flexible and universally applicable, comprehensively reflecting the lifespan of the entire life cycle. Based on the actual operating conditions of the vehicle and the set acceleration test conditions, the obtained acceleration factor and test time can realistically represent the lifespan level of the electrode plates under different operating conditions such as WLTC and CTLC. Furthermore, for the influencing factors of the electrode plates, a test method is proposed to establish single-stress acceleration factors for voltage, temperature, and corrosion ion concentration. Compared to acceleration conditions obtained directly from experiments, this method calibrates model parameters (such as voltage index, activation energy, and ion concentration index) through a single basic experiment, establishes the acceleration relationship between each influencing factor, and then only needs to substitute new usage conditions and test conditions into the formula to calculate the acceleration factor and test time, thereby calculating the product performance after the expected service life. This eliminates the need to determine failure criteria after each test and then determine acceleration conditions based on those criteria, saving significant experimental resource costs, manpower, and time costs.

[0061] Furthermore, the present invention proposes a computer-readable storage medium storing a quality inspection program for a fuel cell bipolar plate. When the quality inspection program is executed by a processor, it implements the quality inspection method for a fuel cell bipolar plate according to any of the above embodiments.

[0062] The computer-readable storage medium of this invention executes a quality detection program for fuel cell bipolar plates stored thereon via a processor. This program can map failure data under accelerated conditions to the actual operating conditions of the fuel cell using a scientific model, thereby achieving high-precision quality prediction.

[0063] Figure 12 This is a block diagram of the quality detection device for fuel cell bipolar plates in an embodiment of the present invention.

[0064] Furthermore, such as Figure 12 As shown, the present invention proposes a quality inspection device 200 for fuel cell bipolar plates, which includes an acquisition module 201 and a determination module 202.

[0065] The module 201 is used to acquire the failure criteria and multiple acceleration variables of the fuel cell bipolar plate. The module 202 is used to determine the acceleration parameters of the fuel cell bipolar plate under multiple acceleration variables by using the failure criteria as the failure parameters of the fuel cell bipolar plate and employing the control variable method and a preset model. The module 201 is also used to acquire the coupling coefficient of the total acceleration factor of the fuel cell bipolar plate. The module 202 is also used to determine the total acceleration factor based on the acceleration parameters and the coupling coefficient. The module 201 is also used to acquire the test duration of the fuel cell bipolar plate reaching the failure parameters under multiple preset acceleration variables and the actual acceleration variables of the fuel cell bipolar plate. The module 202 is also used to determine the real-time life of the fuel cell bipolar plate based on the multiple preset acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor, so as to determine the quality of the fuel cell bipolar plate.

[0066] In some embodiments of the present invention, the determining module 202 is further configured to: prepare a sulfuric acid aqueous solution containing 1 ppm fluoride ions at pH=3, and heat the sulfuric acid aqueous solution to 80°C using a water bath and maintain the temperature stable; set the reference electrode as an Ag / AgCl (saturated KCl) electrode and the counter electrode as a platinum sheet electrode; connect the electrode to be tested to the working electrode, and use potentiodynamic polarization method to scan from 0 to 1V vs. RHE at a scan rate of 1mV / s to obtain a polarization curve, then plot the curve, and finally determine the failure criterion by using the ordinate of the intersection point of the Tafel lines in the plot based on the polarization curve.

[0067] In some embodiments of the present invention, multiple acceleration variables include the concentration of fluoride-containing sulfuric acid aqueous solution, temperature parameters, and voltage parameters.

[0068] In some embodiments of the present invention, the determining module 202 is further configured to: determine the preset model as the Peck model or the inverse power law model when the accelerating variable is the concentration of sulfuric acid aqueous solution containing fluoride ions or the voltage parameter; and determine the preset model as the Arrhenius model when the accelerating variable is the temperature parameter.

[0069] In some embodiments of the present invention, the determining module 202 is further configured to: determine the first acceleration factor of the fuel cell bipolar plate in the concentration of sulfuric acid aqueous solution containing fluoride ions and the second acceleration factor in the voltage parameter by means of an inverse power law model, and determine the third acceleration factor of the fuel cell bipolar plate in the temperature parameter by means of an Arrhenius model; and multiply the first acceleration factor, the second acceleration factor, the third acceleration factor and the coupling coefficient to determine the total acceleration factor.

[0070] In some embodiments of the present invention, the acquisition module 201 is further configured to: acquire multiple sets of acceleration variables and multiple sets of durations corresponding to the failure parameters reached by the fuel cell bipolar plate under multiple sets of acceleration variables; the determination module 202 is further configured to: determine the coupling coefficient based on the multiple sets of acceleration variables and the multiple sets of durations.

[0071] In some embodiments of the present invention, the total acceleration factor is equal to the ratio of the actual usage time of the fuel cell bipolar plate to the test time.

[0072] It should be noted that the specific implementation of the quality detection device for fuel cell bipolar plates in the embodiments of the present invention can be found in the specific implementation of the quality detection method for fuel cell bipolar plates in the above embodiments. To avoid redundancy, it will not be described again here.

[0073] In summary, the fuel cell bipolar plate quality detection device of this invention can map failure data under accelerated conditions to the actual operating conditions of the fuel cell through a scientific model, thereby achieving high-precision quality prediction.

[0074] Figure 13 This is a schematic diagram of a vehicle according to an embodiment of the present invention.

[0075] Furthermore, such as Figure 13 As shown, the present invention proposes a vehicle 300, which includes a fuel cell 301 and a quality inspection device 200 for the bipolar plate of the fuel cell in the above embodiment. The quality inspection device 200 is used to perform quality inspection on the bipolar plate of the fuel cell 301.

[0076] Furthermore, other components and functions of the vehicle in the embodiments of the present invention are known to those skilled in the art, and will not be described in detail here to reduce redundancy.

[0077] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0078] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0079] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0081] Furthermore, the terms "first," "second," etc., used in the embodiments of this invention 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 in this embodiment. Therefore, features defined with terms such as "first" and "second" in the embodiments of this invention can explicitly or implicitly indicate that the embodiment includes at least one of those features. In the description of this invention, the word "multiple" means at least two or more, such as two, three, four, etc., unless otherwise explicitly specified in the embodiments.

[0082] In this invention, unless otherwise explicitly specified or limited in the embodiments, the terms "installation," "connection," "joining," and "fixing" appearing in the embodiments should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can also be a mechanical connection, an electrical connection, etc. Of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific implementation.

[0083] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of 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. "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.

[0084] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for quality inspection of fuel cell bipolar plates, characterized in that, The method includes: Obtain the failure criteria and multiple acceleration variables for the bipolar plate of the fuel cell; Using the failure criteria as the failure parameters of the fuel cell bipolar plate, the acceleration parameters of the fuel cell bipolar plate failure under the multiple acceleration variables are determined by the control variable method and the preset model. Obtain the coupling coefficient of the total acceleration factor of the bipolar plate of the fuel cell; The total acceleration factor is determined based on the acceleration parameters and the coupling coefficient; The test time for the fuel cell bipolar plate to reach the failure parameter under multiple preset acceleration variables and the actual acceleration variables of the fuel cell bipolar plate are obtained. The real-time lifespan of the fuel cell bipolar plate is determined based on the preset multiple acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor.

2. The quality inspection method for fuel cell bipolar plates according to claim 1, characterized in that, The method further includes: Prepare a sulfuric acid aqueous solution with pH=3 containing 1 ppm fluoride ions, and heat the sulfuric acid aqueous solution to 80°C using a water bath and keep the temperature stable; The reference electrode was set as an Ag / AgCl (saturated KCl) electrode, and the counter electrode was set as a platinum sheet electrode. Connect the electrode to be tested to the working electrode, and use the potentiodynamic polarization method to scan from 0 to 1V vs. RHE at a scan rate of 1mV / s to obtain the polarization curve. Then, plot the curve and determine the failure criterion by using the ordinate of the intersection point of the Tafel lines in the plot based on the polarization curve.

3. The quality inspection method for fuel cell bipolar plates according to claim 1, characterized in that, The multiple acceleration variables include the concentration of fluoride-containing sulfuric acid aqueous solution, temperature parameters, and voltage parameters.

4. The quality inspection method for fuel cell bipolar plates according to claim 3, characterized in that, When the accelerating variable is the concentration of sulfuric acid aqueous solution containing fluoride ions or the voltage parameter, the preset model is determined to be the Peck model or the inverse power law model; when the accelerating variable is the temperature parameter, the preset model is determined to be the Arrhenius model.

5. The quality inspection method for fuel cell bipolar plates according to claim 4, characterized in that, The method also includes: The first acceleration factor of the fuel cell bipolar plate in the concentration of sulfuric acid containing fluoride ions and the second acceleration factor in the voltage parameter are determined by the inverse power law model, and the third acceleration factor of the fuel cell bipolar plate in the temperature parameter is determined by the Arrhenius model. The first acceleration factor, the second acceleration factor, the third acceleration factor, and the coupling coefficient are multiplied together to determine the total acceleration factor.

6. The quality inspection method for fuel cell bipolar plates according to claim 1, characterized in that, The method further includes: Obtain multiple sets of acceleration variables and the corresponding multiple sets of time for the fuel cell bipolar plate to reach the failure parameters under the multiple sets of acceleration variables; The coupling coefficient is determined based on the multiple sets of acceleration variables and the multiple sets of durations.

7. The quality inspection method for fuel cell bipolar plates according to claim 1, characterized in that, The total acceleration factor is equal to the ratio of the actual usage time of the fuel cell bipolar plate to the test time.

8. A computer-readable storage medium, characterized in that, It stores a quality inspection program for fuel cell bipolar plates, which, when executed by a processor, implements the quality inspection method for fuel cell bipolar plates according to any one of claims 1-7.

9. A quality inspection device for fuel cell bipolar plates, characterized in that, The device includes: The acquisition module is used to acquire the failure criteria and multiple acceleration variables of the fuel cell bipolar plate; The determination module is used to determine the acceleration parameters of the failure of the fuel cell bipolar plate under the multiple acceleration variables by using the failure criteria as the failure parameters of the fuel cell bipolar plate and employing the control variable method and a preset model. The acquisition module is also used to acquire the coupling coefficient of the total acceleration factor of the fuel cell bipolar plate; The determining module is further configured to determine the total acceleration factor based on the acceleration parameters and the coupling coefficient; The acquisition module is also used to acquire the test time for the fuel cell bipolar plate to reach the failure parameter under multiple preset acceleration variables, and the actual acceleration variables of the fuel cell bipolar plate; The determining module is further configured to determine the real-time lifespan of the fuel cell bipolar plate based on the preset multiple acceleration variables, the test duration, the actual acceleration variables, and the total acceleration factor.

10. A vehicle, characterized in that, The invention includes a fuel cell and a quality inspection device for the fuel cell bipolar plate as described in claim 9, wherein the quality inspection device for the fuel cell bipolar plate is used to perform quality inspection on the bipolar plate of the fuel cell.

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