System and method for testing hydrogen concentration of anode of fuel cell

Abstract

The invention discloses a fuel cell anode hydrogen concentration test system and method, and the system comprises a hydrogen-nitrogen mixed gas extraction assembly, a small single cell test bench, and a nitrogen volume measurement assembly, the input end of the hydrogen-nitrogen mixed gas extraction assembly is connected with an anode subsystem of a fuel cell system; the output end of the hydrogen-nitrogen mixed gas leading-out assembly is connected with the input end of the small single-cell test board, and the output end of the small single-cell test board is connected with the nitrogen volume measuring assembly. According to the scheme, a small single-cell test board is efficiently utilized, and an expensive gas mass spectrometer does not need to be purchased to test the hydrogen concentration of the anode of the fuel cell, so that the test cost is saved; moreover, the reliability of the small single-cell test bench is higher, so that the reliability of hydrogen concentration test is also improved; in addition, the use environment of the small single cell test bench is flexible, so that reliable work in the anode high-humidity environment can be realized, and the reliability of hydrogen concentration test is further improved.

Description

Technical Field

[0001] The present application relates to the field of fuel cell technology, and in particular to a testing system and method for anode hydrogen concentration of a fuel cell. Background Art

[0002] A fuel cell is an energy conversion device that converts chemical energy into electrical energy. When the fuel cell is working, the control of the hydrogen concentration at the anode of the fuel cell system plays a vital role in the stable operation of the system. If the hydrogen concentration is too low, its partial pressure will be insufficient, resulting in a failure of low performance of the single cell; if the hydrogen concentration is too high, the flow resistance of the anode will be low, which is not conducive to the discharge of liquid water, and single cell flooding may occur, causing low performance of the single cell, and the utilization rate of hydrogen will decrease. In existing fuel cell systems, the exhaust solenoid valve is generally opened periodically to maintain the hydrogen concentration at the anode within a stable range. During the system development process, the opening frequency of the exhaust solenoid valve needs to be calibrated to maintain the hydrogen concentration at the anode, but the current technology is limited by the measurement method of the anode hydrogen concentration, and it is difficult to accurately measure the hydrogen concentration on the anode side.

[0003] Traditionally, a hydrogen concentration sensor is usually used to measure the hydrogen concentration on the anode side, but the hydrogen concentration sensor cannot work reliably in a high humidity environment at the anode. In addition, in the laboratory, a mass spectrometer is often used to test the hydrogen concentration on the anode side, but the equipment is expensive and the reliability of the equipment itself is average, and it often fails. Summary of the invention

[0004] The present application aims to at least solve the technical problems existing in the prior art. To this end, the first aspect of the present application proposes a test system for the hydrogen concentration of a fuel cell anode, characterized in that the system includes a hydrogen-nitrogen mixed gas outlet component, a small single-cell test bench, and a nitrogen volume measurement component; the input end of the hydrogen-nitrogen mixed gas outlet component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas outlet component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component; wherein, A hydrogen-nitrogen mixed gas outlet assembly is used to lead the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem to a small single-cell test bench for processing before the gas enters the anode circulation system; A small single-cell test bench, used to remove hydrogen from a hydrogen-nitrogen mixed gas at a current current and a preset voltage, so that the anode tail exhaust of the small single-cell test bench contains only nitrogen; The nitrogen volume measurement component is used to obtain the nitrogen in the anode tail exhaust of a small single-cell test bench and obtain the volume of the nitrogen.

[0005] In a possible implementation, the hydrogen-nitrogen mixed gas outlet assembly includes a hydrogen-nitrogen mixed gas induction manifold and a regulating valve; the input end of the regulating valve is connected to the anode subsystem of the fuel cell system, the output end of the regulating valve is connected to the input end of the induction manifold, and the output end of the hydrogen-nitrogen mixed gas induction manifold is connected to the input end of the small single-cell test bench; wherein, A regulating valve for regulating the gas flow of the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem before entering the anode circulation system; The hydrogen-nitrogen mixed gas inlet manifold is used to lead the hydrogen-nitrogen mixed gas after gas flow adjustment to the small single-cell test bench for processing.

[0006] In one possible embodiment, the nitrogen volume measurement assembly includes an anode tail exhaust induction manifold, a water container and a measuring cup with a scale; the input end of the anode tail exhaust induction manifold is connected to the output end of the small single cell test bench, the output end of the anode tail exhaust induction manifold is placed in a measuring cup with a scale, and the measuring cup with a scale is placed in the water container after filling with water.

[0007] In a possible implementation, the anode of the small single-cell test bench is provided with an anti-reverse polarity catalyst, and the anti-reverse polarity catalyst is used to maintain the voltage of the small single-cell test bench at a preset voltage by resisting reverse current.

[0008] The second aspect of the present application provides a method for testing the hydrogen concentration of a fuel cell anode, which is applied to the system for hydrogen concentration of a fuel cell anode as described in the first aspect, wherein the system comprises a hydrogen-nitrogen mixed gas outlet assembly, a small single-cell test bench, and a nitrogen volume measurement assembly; the input end of the hydrogen-nitrogen mixed gas outlet assembly is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas outlet assembly is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement assembly; the method comprises: The hydrogen-nitrogen mixed gas outlet assembly is used to lead the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem to a small single-cell test bench for treatment before the gas enters the anode circulation system; By removing hydrogen from the hydrogen-nitrogen mixed gas at the current current and the preset voltage of the small single-cell test bench, the anode tail exhaust of the small single-cell test bench contains only nitrogen; wherein the current current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas, the current current changes with time, and is used to maintain the voltage of the small single-cell test bench at the preset voltage; The nitrogen in the anode tail exhaust of the small single-cell test bench is obtained through the nitrogen volume measurement component, and the volume of the nitrogen is obtained; wherein the volume of the nitrogen is used to calculate the molar mass of the nitrogen in the hydrogen-nitrogen mixed gas; The hydrogen concentration at the anode of the fuel cell is determined by the molar mass of hydrogen and the molar mass of nitrogen.

[0009] In one possible implementation, the current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas, including: Integrate the current within the target time period to obtain an integral value; Based on the integral value and Faraday's constant, calculate the molar mass of hydrogen in the hydrogen-nitrogen mixture.

[0010] In one possible implementation, the volume of nitrogen is used to calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas: Obtaining a first temperature value under standard conditions and a second temperature value when collecting nitrogen; The molar mass of nitrogen in the hydrogen-nitrogen mixed gas is calculated based on the volume of nitrogen, the first temperature value, and the second temperature value.

[0011] In a possible implementation, determining the hydrogen concentration of the anode of the fuel cell by the molar mass of hydrogen and the molar mass of nitrogen includes: Determine the molar mass of the hydrogen-nitrogen mixed gas based on the sum of the molar mass of hydrogen and the molar mass of nitrogen; The hydrogen concentration at the anode of the fuel cell is determined based on the ratio of the molar mass of hydrogen to the molar mass of the hydrogen-nitrogen mixed gas.

[0012] In a possible implementation, the method further includes: Acquire a plurality of preset current densities corresponding to the fuel cell system; For each preset current density, obtaining the hydrogen concentration of the fuel cell anode of the fuel cell system at the preset current density; Compare the hydrogen concentration at the anode of the fuel cell with the target hydrogen concentration preset in the small single-cell test bench to generate a comparison result; Based on the comparison results, the hydrogen concentration inside the fuel cell system at each preset current density is calibrated respectively.

[0013] In a possible implementation, before obtaining the hydrogen concentration of the fuel cell anode of the fuel cell system at a preset current density, the method further includes: For each preset current density, after the fuel cell system is turned on, controlling the fuel cell system to stably operate at the preset current density; After the small single-cell test bench is controlled to be turned on, the regulating valve of the small single-cell test bench is adjusted to maintain the voltage of the small single-cell test bench at a preset voltage, and the regulating valve is controlled to be closed; After confirming that the nitrogen volume measurement component is set successfully, the control regulating valve is reopened, and after the collected nitrogen meets the preset conditions, the control regulating valve is closed.

[0014] The embodiments of the present application have the following beneficial effects: The test system for the hydrogen concentration of the fuel cell anode provided by the embodiment of the present application includes: a hydrogen-nitrogen mixed gas lead-out component, a small single-cell test bench, and a nitrogen volume measurement component. The input end of the hydrogen-nitrogen mixed gas lead-out component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas lead-out component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component. This solution saves the test cost by efficiently utilizing the small single-cell test bench, and there is no need to purchase a relatively expensive gas mass spectrometer to test the hydrogen concentration of the fuel cell anode; and because the reliability of the small single-cell test bench is high, the reliability of the hydrogen concentration test is also improved; in addition, because the use environment of the small single-cell test bench is relatively flexible, it can achieve reliable operation in an environment with high humidity of the anode, further improving the reliability of the hydrogen concentration test. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A framework diagram of a fuel cell anode hydrogen concentration test system provided in an embodiment of the present application; Figure 2 A schematic diagram of the specific structure of a fuel cell anode hydrogen concentration test system provided in an embodiment of the present application; Figure 3 A flowchart of a method for testing hydrogen concentration at anode of a fuel cell provided in an embodiment of the present application; Figure 4 A flowchart of the steps for calculating the molar mass of hydrogen in a hydrogen-nitrogen mixed gas provided in an embodiment of the present application; Figure 5 A flowchart of the steps for calculating the molar mass of nitrogen in a hydrogen-nitrogen mixed gas provided in an embodiment of the present application; Figure 6 A flowchart of the steps for determining the hydrogen concentration at the anode of a fuel cell provided in an embodiment of the present application; Figure 7 A flowchart of the steps for calibrating the hydrogen concentration inside a fuel cell system provided in an embodiment of the present application; Figure 8 A flowchart of the steps for adjusting a regulating valve of a fuel cell system and a small single-cell test bench provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] The terms used in this application are only for the purpose of describing specific embodiments, and are not intended to limit this application. Unless otherwise defined, the technical terms or scientific terms used in this application should be understood by people with ordinary skills in the field to which this application belongs. The singular forms of "a", "said" and "the" used in this application specification and the attached claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items. In the description of the embodiments of the present application, it is necessary to understand that the orientation or position relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or position relationship shown in the drawings, only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present application.

[0018] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the embodiments of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0019] In the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0020] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0021] It should be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be a centered element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a centered element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the embodiments of the present application are for illustrative purposes only and are not intended to be the only implementation method.

[0022] In the related art, the exhaust solenoid valve is generally opened periodically to maintain the hydrogen concentration at the anode within a stable range. During the system development process, the opening frequency of the exhaust solenoid valve needs to be calibrated to maintain the hydrogen concentration at the anode, but the current technology is limited by the measurement method of the anode hydrogen concentration, and it is difficult to accurately measure the hydrogen concentration on the anode side. Traditionally, a hydrogen concentration sensor is usually used to measure the hydrogen concentration on the anode side, but the hydrogen concentration sensor cannot work reliably in an environment with high humidity at the anode; in addition, in the laboratory, a mass spectrometer is often used to test the hydrogen concentration on the anode side, but the equipment is expensive, and the reliability of the equipment itself is average, and it often fails.

[0023] Based on this, the present application provides a test system and method for the hydrogen concentration of a fuel cell anode, the system comprising: a hydrogen-nitrogen mixed gas lead-out component, a small single-cell test bench, and a nitrogen volume measurement component, wherein the input end of the hydrogen-nitrogen mixed gas lead-out component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas lead-out component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component. This solution saves the test cost by efficiently utilizing the small single-cell test bench, and there is no need to purchase a relatively expensive gas mass spectrometer to test the hydrogen concentration of the fuel cell anode; and, since the reliability of the small single-cell test bench is high, the reliability of the hydrogen concentration test is also improved; in addition, since the use environment of the small single-cell test bench is relatively flexible, it can achieve reliable operation in an environment with high humidity of the anode, further improving the reliability of the hydrogen concentration test.

[0024] Figure 1 A framework diagram of a test system for hydrogen concentration at the anode of a fuel cell provided in an embodiment of the present application, the system includes a hydrogen-nitrogen mixed gas lead-out component, a small single-cell test bench, and a nitrogen volume measurement component. The input end of the hydrogen-nitrogen mixed gas lead-out component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas lead-out component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component.

[0025] The hydrogen-nitrogen mixed gas outlet assembly is used to lead the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem to the small single-cell test bench for processing before the gas enters the anode circulation system.

[0026] In some optional embodiments, Figure 2 As shown, Figure 2 A schematic diagram of the specific structure of a fuel cell anode hydrogen concentration testing system provided in an embodiment of the present application.

[0027] The anode subsystem, namely the fuel cell anode subsystem 1, may generally include a fuel cell stack, a hydrogen supply, an inlet pressure sensor, an outlet pressure sensor, an exhaust valve, a drain valve, an anode circulation system and other parts.

[0028] The hydrogen-nitrogen mixed gas outlet assembly includes a hydrogen-nitrogen mixed gas induction manifold 3 and a regulating valve 2. The input end of the regulating valve 2 is connected to the anode subsystem 1 of the fuel cell system, the output end of the regulating valve 2 is connected to the input end of the hydrogen-nitrogen mixed gas induction manifold 3, and the output end of the hydrogen-nitrogen mixed gas induction manifold 3 is connected to the input end of the small single-cell test bench 4.

[0029] The regulating valve 2 is used to adjust the gas flow of the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem before entering the anode circulation system. The hydrogen-nitrogen mixed gas induction manifold 3 is used to lead the hydrogen-nitrogen mixed gas after the gas flow is adjusted to the small single cell test bench 4 for processing.

[0030] The small single-cell test bench 4 is used to remove hydrogen from the hydrogen-nitrogen mixed gas under the current current and the preset voltage, so that the anode tail exhaust of the small single-cell test bench contains only nitrogen.

[0031] The current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas. The current changes with time and is used to maintain the voltage of the small single-cell test bench at a preset voltage. Optionally, the current can be recorded as I, where I is a variable that changes with time t, so that the molar mass of hydrogen N can be calculated by formula (1): H2 .

[0032] N H2 =∫Idt / 2*F (1) Where F is the Faraday constant.

[0033] In some optional embodiments, the preset voltage is -0.2 V. At this preset voltage, the hydrogen in the hydrogen-nitrogen mixed gas is completely consumed, or penetrates to the cathode, so that only nitrogen remains.

[0034] Optionally, after turning on the small single-cell test bench, if the current current is too large or too small and exceeds the measuring range of the small single-cell test bench, the gas flow rate of the hydrogen-nitrogen mixed gas can be adjusted by adjusting the valve to adjust the current current, so as to control the voltage to maintain it at a preset voltage.

[0035] In some optional embodiments, the anode of the small single cell test bench may be provided with an anti-reverse polarity catalyst, and the anti-reverse polarity catalyst is used to further ensure that the voltage of the small single cell test bench is maintained at a preset voltage by resisting reverse current.

[0036] In some optional embodiments, the size of the small single-cell test bench can be 5*5cm, and there is no need for an overly large small single-cell test bench. This not only saves resources, but also does not require the use of too much hydrogen-nitrogen mixed gas to accurately calculate the hydrogen concentration at the fuel cell anode, without affecting the normal operation of the fuel cell.

[0037] The nitrogen volume measurement component is used to obtain the nitrogen in the anode tail exhaust of a small single-cell test bench and obtain the volume of the nitrogen.

[0038] In some optional embodiments, please continue to refer to Figure 2 , the nitrogen volume measurement component includes an anode tail exhaust induction manifold 5, a water container 6 and a measuring cup 7 with a scale. The input end of the anode tail exhaust induction manifold 5 is connected to the output end of the small single cell test bench 4, and the output end of the anode tail exhaust induction manifold 5 is placed in a measuring cup 7 with a scale. The measuring cup 7 with a scale is placed in the water container 6 after being filled with water, so that the volume of nitrogen in the anode tail exhaust enters the measuring cup 7 with a scale, and the water displacement method is used to determine the volume of nitrogen. Optionally, the water in the container can be maintained at a room temperature of about 25°C. Among them, the specific process of determining the volume of nitrogen by the water displacement method can refer to the prior art, which will not be repeated here.

[0039] The volume of nitrogen is used to calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas, and the molar mass of hydrogen and nitrogen are used to determine the hydrogen concentration at the anode of the fuel cell. Optionally, after measuring the volume V of nitrogen within a certain period of time, it can be converted into the molar mass of nitrogen N by formula (2): N2 .

[0040] N N2 =V / 22.4*T2 / T1 (2) Among them, T2 is the temperature under standard conditions, which is 273.15K, and T1 is the temperature when collecting nitrogen. Since the water in the container is at room temperature of about 25°C, T2 is approximately 298.15K.

[0041] In some optional embodiments, the hydrogen molar mass N is calculated. H2 The molar mass of nitrogen N N2 Finally, the sum of the molar mass of hydrogen and the molar mass of nitrogen is used to determine the molar mass of the hydrogen-nitrogen mixed gas, and the ratio of the molar mass of hydrogen to the molar mass of the hydrogen-nitrogen mixed gas is used to determine the hydrogen concentration at the anode of the fuel cell.

[0042] Among them, the molar mass of hydrogen and nitrogen mixed gas is N H2 +N N2 Therefore, the hydrogen concentration H2% in the hydrogen-nitrogen mixed gas can be calculated by formula (3).

[0043] H2%=N H2 / (N H2 +N N2 ) (3) Since the hydrogen concentration in the drawn hydrogen-nitrogen mixed gas is the same as the hydrogen concentration in the anode subsystem entering the anode circulation system, the hydrogen concentration in the fuel cell anode is also the hydrogen concentration H2% in the hydrogen-nitrogen mixed gas, which is the value calculated by formula (3).

[0044] The test system for the hydrogen concentration of the fuel cell anode provided in this embodiment includes: a hydrogen-nitrogen mixed gas lead-out component, a small single-cell test bench, and a nitrogen volume measurement component. The input end of the hydrogen-nitrogen mixed gas lead-out component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas lead-out component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component. This solution saves the test cost by efficiently utilizing the small single-cell test bench, and there is no need to purchase a relatively expensive gas mass spectrometer to test the hydrogen concentration of the fuel cell anode; and because the reliability of the small single-cell test bench is high, the reliability of the hydrogen concentration test is also improved; in addition, because the use environment of the small single-cell test bench is relatively flexible, it can achieve reliable operation in a high humidity environment of the anode, further improving the reliability of the hydrogen concentration test.

[0045] like Figure 3 As shown, Figure 3A flow chart of the steps of a method for testing the hydrogen concentration of a fuel cell anode provided in an embodiment of the present application is applied to the system of the hydrogen concentration of a fuel cell anode, the system includes a hydrogen-nitrogen mixed gas outlet component, a small single-cell test bench, and a nitrogen volume measurement component; the input end of the hydrogen-nitrogen mixed gas outlet component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas outlet component is connected to the input end of the small single-cell test bench, and the output end of the small single-cell test bench is connected to the nitrogen volume measurement component. The method includes: Step 302: Before the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem enters the anode circulation system, the hydrogen-nitrogen mixed gas is led out to the small single-cell test bench for processing through the hydrogen-nitrogen mixed gas leading-out component.

[0046] Step 304: remove hydrogen from the hydrogen-nitrogen mixed gas at the current current and the preset voltage through the small single-cell test bench, so that the anode tail exhaust of the small single-cell test bench contains only nitrogen.

[0047] Among them, the current current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas, the current current changes with time, and is used to maintain the voltage of the small single-cell test bench at a preset voltage.

[0048] Step 306: Obtain nitrogen in the anode tail exhaust of the small single-cell test bench through the nitrogen volume measurement component, and obtain the volume of the nitrogen.

[0049] The volume of nitrogen is used to calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas.

[0050] Step 308: Determine the hydrogen concentration at the anode of the fuel cell according to the molar mass of hydrogen and the molar mass of nitrogen.

[0051] In some optional embodiments, Figure 4 As shown, Figure 4 A flowchart of the steps for calculating the molar mass of hydrogen in a hydrogen-nitrogen mixed gas provided in an embodiment of the present application includes: Step 402: Integrate the current within the target time period to obtain an integral value.

[0052] Step 404: Calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas based on the integral value and the Faraday constant.

[0053] In some optional embodiments, Figure 5 As shown, Figure 5 A flowchart of steps for calculating the molar mass of nitrogen in a hydrogen-nitrogen mixed gas provided in an embodiment of the present application includes: Step 502: Acquire a first temperature value under standard conditions and a second temperature value when collecting nitrogen.

[0054] Step 504: Calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas based on the volume of nitrogen, the first temperature value, and the second temperature value.

[0055] In some optional embodiments, Figure 6 As shown, Figure 6 A flowchart of the steps for determining the hydrogen concentration of a fuel cell anode provided in an embodiment of the present application includes: Step 602: Determine the molar mass of the hydrogen-nitrogen mixed gas based on the sum of the molar mass of the hydrogen and the molar mass of the nitrogen.

[0056] Step 604: Determine the hydrogen concentration at the anode of the fuel cell based on the ratio of the molar mass of hydrogen to the molar mass of the hydrogen-nitrogen mixed gas.

[0057] It should be noted that the specific implementation process of each embodiment of the above method can refer to the process of each embodiment of the system of the above fuel cell anode hydrogen concentration, which will not be repeated here.

[0058] This embodiment makes efficient use of the small single-cell test bench, and there is no need to purchase a relatively expensive gas mass spectrometer to test the hydrogen concentration of the fuel cell anode, thereby saving testing costs; and since the small single-cell test bench has a high reliability, the reliability of the hydrogen concentration test is also improved; in addition, since the use environment of the small single-cell test bench is relatively flexible, it can achieve reliable operation in a high-humidity environment of the anode, further improving the reliability of the hydrogen concentration test.

[0059] The present application also provides a method for applying the above-mentioned fuel cell anode hydrogen concentration test method to a specific process of calibrating the hydrogen concentration inside the fuel cell anode subsystem, such as Figure 7 As shown, Figure 7 A flowchart of the steps for calibrating the hydrogen concentration inside a fuel cell system provided in an embodiment of the present application includes: Step 702: Obtain a plurality of preset current densities corresponding to the fuel cell system.

[0060] Step 704: for each preset current density, obtain the hydrogen concentration of the fuel cell anode of the fuel cell system at the preset current density.

[0061] Step 706: Compare the hydrogen concentration at the anode of the fuel cell with the target hydrogen concentration preset by the small single-cell test bench to generate a comparison result.

[0062] Step 708: Based on the comparison results, calibrate the hydrogen concentration inside the fuel cell system at each preset current density.

[0063] Among them, when calibrating the hydrogen concentration at different current densities of the fuel cell system, multiple preset current densities can be pre-customized, and can be 100CD, 200CD, etc. Then, for each preset current density, the anode hydrogen concentration of the fuel cell system at the preset current density can be obtained. The specific calculation method of the anode hydrogen concentration of the fuel cell can refer to the above embodiments, which will not be repeated here.

[0064] In some optional embodiments, before obtaining the fuel cell anode hydrogen concentration of the fuel cell system at a preset current density, it is also necessary to adjust the regulating valves of the fuel cell system and the small single-cell test bench, such as Figure 8 As shown, Figure 8 A flowchart of the steps of regulating a regulating valve of a fuel cell system and a small single-cell test bench provided in an embodiment of the present application includes: Step 802 : for each preset current density, after the fuel cell system is turned on, control the fuel cell system to stably operate at the preset current density.

[0065] Step 804, after the small single-cell test bench is controlled to be turned on, the regulating valve of the small single-cell test bench is adjusted to maintain the voltage of the small single-cell test bench at a preset voltage, and the regulating valve is controlled to be closed.

[0066] Step 806: After determining that the nitrogen volume measurement component is successfully set, control the regulating valve to reopen, and after the collected nitrogen meets the preset conditions, control the regulating valve to close.

[0067] When calibrating the hydrogen concentration of the fuel cell system at different preset current densities, the fuel cell system may be started first, operated at each preset current density, and wait for the operation to become stable.

[0068] Next, you can turn on the 5*5cm small single cell test bench, first adjust the regulating valve of the mixed gas, control the current to maintain the voltage at the preset voltage, that is, make the voltage -0.2V, and the gas flow adjusted by the regulating valve is best to control the current at about 200CD of the 5*5cm small single cell test bench, and set the load mode to constant pressure mode.

[0069] After the adjustment is completed, you can close the regulating valve first, and reopen the regulating valve after the nitrogen volume measuring component is ready. Then wait for a while, and close the regulating valve after the amount of collected nitrogen is maintained at the optimal identification scale line, that is, after the preset conditions are met.

[0070] After obtaining the fuel cell anode hydrogen concentration calculated according to the above-mentioned fuel cell anode hydrogen concentration test method under the preset current density, the calculated result can be compared with the target hydrogen concentration pre-set by the small single-cell test bench, and the opening frequency of the exhaust valve can be increased or decreased based on the comparison result, and then the test is repeated until the calculated result is the same as the target hydrogen concentration.

[0071] Finally, the current density can be increased in sequence, and the above steps can be repeated until the hydrogen concentration calibration inside the fuel cell system is completed at all preset current densities.

[0072] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0073] It is easy to understand that those skilled in the art can combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments based on the several embodiments provided in the present application, and these embodiments do not exceed the protection scope of the present application.

[0074] The above specific implementation methods further explain in detail the purpose, technical solutions and beneficial effects of the embodiments of the present application. It should be understood that the above are only specific implementation methods of the embodiments of the present application and are not used to limit the protection scope of the embodiments of the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the protection scope of the embodiments of the present application.

Claims

1. A fuel cell anode hydrogen concentration test system, characterized in that: The system comprises a hydrogen-nitrogen mixed gas outlet component, a small single cell test bench, and a nitrogen volume measurement component; the input end of the hydrogen-nitrogen mixed gas outlet component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas outlet component is connected to the input end of the small single cell test bench, and the output end of the small single cell test bench is connected to the nitrogen volume measurement component; wherein, The hydrogen-nitrogen mixed gas outlet assembly is used to lead the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem to the small single-cell test bench for processing before the hydrogen-nitrogen mixed gas enters the anode circulation system; The small single-cell test bench is used to remove hydrogen from the hydrogen-nitrogen mixed gas at a current current and a preset voltage, so that the anode tail exhaust of the small single-cell test bench contains only nitrogen; The nitrogen volume measuring component is used to obtain nitrogen in the anode tail exhaust of the small single-cell test bench and obtain the volume of the nitrogen.

2. The system according to claim 1, characterized in that The hydrogen-nitrogen mixed gas outlet assembly includes a hydrogen-nitrogen mixed gas induction manifold and a regulating valve; the input end of the regulating valve is connected to the anode subsystem of the fuel cell system, the output end of the regulating valve is connected to the input end of the induction manifold, and the output end of the hydrogen-nitrogen mixed gas induction manifold is connected to the input end of the small single-cell test bench; wherein, The regulating valve is used to regulate the gas flow of the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem before entering the anode circulation system; The hydrogen-nitrogen mixed gas induction manifold is used to guide the hydrogen-nitrogen mixed gas after gas flow adjustment to the small single-cell test bench for processing.

3. The system according to claim 1 or 2, characterized in that: The nitrogen volume measurement assembly includes an anode tail exhaust induction manifold, a water container and a measuring cup with a scale; the input end of the anode tail exhaust induction manifold is connected to the output end of the small single cell test bench, the output end of the anode tail exhaust induction manifold is placed in the measuring cup with a scale, and the measuring cup with a scale is placed in the water container after being filled with water.

4. The system according to claim 1 or 2, characterized in that: The anode of the small single cell test bench is provided with an anti-reverse polarity catalyst, and the anti-reverse polarity catalyst is used to maintain the voltage of the small single cell test bench at the preset voltage by resisting reverse current.

5. A method for testing the hydrogen concentration of a fuel cell anode, characterized in that: Applicable to the system for measuring the hydrogen concentration at the anode of a fuel cell according to any one of claims 1 to 4, the system comprising a hydrogen-nitrogen mixed gas outlet component, a small single cell test bench, and a nitrogen volume measurement component; the input end of the hydrogen-nitrogen mixed gas outlet component is connected to the anode subsystem of the fuel cell system, the output end of the hydrogen-nitrogen mixed gas outlet component is connected to the input end of the small single cell test bench, and the output end of the small single cell test bench is connected to the nitrogen volume measurement component; the method comprises: The hydrogen-nitrogen mixed gas outlet assembly is used to lead the hydrogen-nitrogen mixed gas at the outlet of the anode subsystem to the small single-cell test bench for treatment before the hydrogen-nitrogen mixed gas enters the anode circulation system; The small single cell test bench removes hydrogen from the hydrogen-nitrogen mixed gas at a current current and a preset voltage, so that the anode tail exhaust of the small single cell test bench contains only nitrogen; wherein the current current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas, the current current changes with time, and is used to maintain the voltage of the small single cell test bench at the preset voltage; The nitrogen in the anode tail exhaust of the small single-cell test bench is obtained by the nitrogen volume measurement component, and the volume of the nitrogen is obtained; wherein the volume of the nitrogen is used to calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas; The hydrogen concentration at the anode of the fuel cell is determined by the hydrogen molar mass and the nitrogen molar mass.

6. The method according to claim 5, characterized in that The current is used to calculate the molar mass of hydrogen in the hydrogen-nitrogen mixed gas, including: Integrating the current within a target time period to obtain an integral value; The molar mass of hydrogen in the hydrogen-nitrogen mixed gas is calculated based on the integral value and the Faraday constant.

7. The method according to claim 5, characterized in that The volume of nitrogen is used to calculate the molar mass of nitrogen in the hydrogen-nitrogen mixed gas, including: Obtaining a first temperature value under standard conditions and a second temperature value when collecting nitrogen; The molar mass of nitrogen in the hydrogen-nitrogen mixed gas is calculated based on the volume of the nitrogen, the first temperature value, and the second temperature value.

8. The method according to any one of claims 5 to 7, characterized in that: The step of determining the hydrogen concentration at the anode of the fuel cell by using the hydrogen molar mass and the nitrogen molar mass comprises: Determining the molar mass of the hydrogen-nitrogen mixed gas based on the sum of the molar mass of the hydrogen and the molar mass of the nitrogen; The hydrogen concentration at the anode of the fuel cell is determined based on the ratio of the molar mass of the hydrogen gas to the molar mass of the hydrogen-nitrogen mixed gas.

9. The method according to any one of claims 5 to 7, characterized in that: The method further comprises: Acquiring a plurality of preset current densities corresponding to the fuel cell system; For each of the preset current densities, obtaining the anode hydrogen concentration of the fuel cell of the fuel cell system at the preset current density; Comparing the hydrogen concentration of the anode of the fuel cell with the target hydrogen concentration preset by the small single-cell test bench to generate a comparison result; Based on the comparison results, the hydrogen concentration inside the fuel cell system at each preset current density is calibrated respectively.

10. The method according to claim 9, characterized in that Before obtaining the anode hydrogen concentration of the fuel cell of the fuel cell system at the preset current density, the method further includes: For each of the preset current densities, after the fuel cell system is turned on, controlling the fuel cell system to stably operate at the preset current density; After the small single cell test bench is controlled to be turned on, the regulating valve of the small single cell test bench is adjusted to maintain the voltage of the small single cell test bench at a preset voltage, and the regulating valve is controlled to be closed; After determining that the nitrogen volume measurement component is successfully set, the regulating valve is controlled to reopen, and after the collected nitrogen meets the preset conditions, the regulating valve is controlled to close.

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