Airtightness detection device and airtightness detection method

Abstract

The invention relates to an air tightness detection device and an air tightness detection method, the air tightness detection device comprises an air supply module, a flow test module, an external leakage test module and a series leakage test module, the flow test module is connected with an outlet of the air supply module through a first air inlet pipeline, and the flow test module comprises a flow test pipeline and a bypass pipeline; the flow testing pipeline is provided with a flow meter, and the bypass pipeline is provided with a bypass valve; the outleakage testing module comprises a first testing pipe group and an outleakage valve on a first air inlet pipeline, and one end of the first testing pipeline is connected with the flow testing module; the other end is connected with the plurality of cavities through a first valve group; the series leakage testing module comprises a second testing pipe set, the second testing pipe set is provided with a second valve set, one end of the second testing pipe set is connected with the multiple cavities in an on-off mode through the second valve set, and the other end of the second testing pipe set is connected with the flow testing module. The airtightness detection device can carry out a single-cavity leakage test and a multi-cavity series leakage test on the fuel cell under the condition that only one flowmeter is needed.

Description

Technical Field

[0001] The present disclosure relates to the technical field of fuel cells, and in particular, to an airtightness detection device and an airtightness detection method. Background Art

[0002] As a key power source for new energy vehicles, hydrogen fuel cells work by stacking and connecting multiple single cells in series to form a stack. The stack contains circulation cavities for different fluids such as oxidants, fuels and coolants, such as air cavities, hydrogen cavities and cold cavities. Strict sealing and isolation are required between the multiple cavities to ensure the normal operation of the battery. Therefore, the air tightness of the multiple cavities of the hydrogen fuel cell is one of the important indicators for judging the safety performance of the hydrogen fuel cell. The current air tightness test of hydrogen fuel cells usually includes a single-cavity external leakage test and a multi-cavity cross leakage test. In the single-cavity external leakage test, multiple flow meters are usually required for leakage judgment. In the single-cavity external leakage test, the arrangement of the flow meters in the single-cavity external leakage test cannot be directly applied to the multi-cavity cross leakage test. The multi-cavity cross leakage test can only be performed after the flow meters are rearranged, which can easily lead to low test efficiency such as a cumbersome test process and a long test time, and occupies more components. Summary of the invention

[0003] The purpose of the present disclosure is to provide an airtight detection device and an airtight detection method, which can perform single-cavity external leakage test and multi-cavity cross leakage test on a fuel cell with only one flow meter, so as to reduce the number of occupied components and improve the test efficiency, so as to at least partially solve the above-mentioned technical problems.

[0004] In order to achieve the above-mentioned purpose, the first aspect of the present disclosure provides an airtightness detection device for performing airtightness detection on a fuel cell, wherein the fuel cell includes a plurality of cavities, and the airtightness detection device includes: an air supply module; a flow test module, connected to the outlet of the air supply module through a first air inlet pipeline, the flow test module including a flow test pipeline and a bypass pipeline, the flow test pipeline is provided with a flow meter, and the bypass pipeline is provided with a bypass valve; an external leakage test module, including a first test tube group and an external leakage valve located on the first air inlet pipeline, one end of the first test tube group is connected to the flow test module; the other end is used for being connected to the plurality of cavities through a first valve group in an on-off manner; and a cross-talk test module, including a second test tube group, the second test tube group is provided with a second valve group, one end of the second test tube group is connected to the plurality of cavities in an on-off manner through the second valve group, and the other end is connected to the flow test module.

[0005] Optionally, the fuel cell is configured as a hydrogen fuel cell, and the plurality of cavities include an air cavity, a hydrogen cavity and a cold cavity.

[0006] Optionally, the first test tube group includes a first main pipe and three first branch pipes, the first main pipe is connected to the cavity, the hydrogen chamber and the cold chamber one by one through the three first branch pipes; the first valve group includes three first stop valves, and the first stop valves are arranged one by one on the first branch pipes.

[0007] Optionally, the second test tube group includes a second main pipe and three second branches, the second main pipe is connected to the cavity, the hydrogen chamber and the cold chamber one by one through the three second branches; a leakage valve is provided on the second main pipe, and the outlet of the second main pipe is connected to the flow test module; the second valve group includes three second stop valves, and the second stop valves are arranged one by one on the second branches.

[0008] Optionally, the leakage test module also includes a third valve group and a second air intake pipeline, the second air intake pipeline includes a second air intake branch respectively connected to the air supply module and each of the cavities; the third valve group includes a third stop valve respectively arranged on each of the second air intake branches.

[0009] Optionally, the flow test module further includes: a flow meter front valve, which is arranged in the flow test pipeline and located upstream of the flow meter; and a flow meter rear valve, which is arranged in the flow test pipeline and located downstream of the flow meter.

[0010] Optionally, the external leakage test module also includes a first external discharge pipeline connected to the flow test module and the first test tube group, and a first exhaust valve is provided on the first external discharge pipeline; and / or the cross-link leakage test module also includes a second external discharge pipeline connected to the second test tube group, and a second exhaust valve is provided on the second external discharge pipeline.

[0011] Optionally, the air supply module comprises a first air supply member and a second air supply member, and the air supply pressure of the first air supply member is higher than the air supply pressure of the second air supply member.

[0012] A second aspect of the present disclosure provides an airtight detection method for leak detection of a fuel cell, the method adopts the airtight detection device described in any of the above optional schemes, the method comprising: opening the external leakage valve and the bypass valve, and the gas supply module inflates multiple cavities of the fuel cell to a first preset pressure along the first test tube group through the bypass pipeline; after inflating the flow test pipeline to the first preset pressure through the gas supply module, the bypass valve is closed; after standing for a first preset time, a first measured flow of the flow meter is obtained.

[0013] Optionally, the method also includes: opening the bypass valve, and the gas supply module inflates at least one of the multiple cavities of the fuel cell to a second preset pressure; at least partially opening the second valve group, and after the other two of the multiple cavities inflate the flow test pipeline to the second preset pressure, closing the bypass valve; after standing for a second preset time, obtaining the second measured flow of the flow meter.

[0014] By means of the above technical scheme, that is, by means of the airtight detection device provided by the present invention, when the fuel cell is subjected to airtight detection, a single-chamber external leakage test and a multi-chamber cross-leakage test can be respectively performed on the fuel cell by means of only one flow meter, that is, when performing a single-chamber external leakage test, the bypass valve and the external leakage valve can be opened, and the multiple cavities of the fuel cell can be inflated through the bypass pipeline using the air supply module, and after the pressure inside the multiple cavities is inflated to a preset pressure so that the pressures are stabilized, the flow test pipeline of the flow test module can be inflated through the air supply module, and the flow test pipeline located before the flow meter and the flow test pipeline can be inflated. When the pipeline pressure after the meter tends to be stable, the value of the flow meter is reset to zero, and after a preset period of time, the leakage of multiple chambers is judged by observing the measured instantaneous flow of the flow meter. That is, it can be understood that if there is leakage, the previously inflated gas will leak out from the leakage points of multiple chambers, and as the gas is discharged and the air pressure gradually decreases, the instantaneous flow displayed by the flow meter will increase, which can be used to judge that multiple chambers of the fuel cell have leakage; when conducting a multi-chamber leakage test, you can first open the second valve group connected to one of the chambers The valve of the body is opened, and the cavity is inflated through the air supply module. When the air pressure in one cavity meets the preset pressure and tends to be stable, the valve in the second valve group connected to the other cavity is opened, and the pipelines located before and after the flow meter of the flow test pipeline are inflated through the air supply module. After the pressure tends to be stable, the flow meter is reset to zero, and after standing for a preset time, the measured instantaneous flow of the flow meter is observed to determine the leakage between any two cavities in the multiple cavities. That is, it can be understood that if there is a leakage, the previous leakage of another cavity The inflated gas will leak outward, and as the gas is discharged outward and the air pressure gradually decreases, the instantaneous flow rate displayed by the flow meter will increase, thereby judging that there is a cross-leakage between the above two cavities. When the instantaneous flow rate displayed by the flow meter is zero, it means that there is no cross-leakage between the above two cavities. When the fuel cell is subjected to a single-cavity external leakage test and a multi-cavity cross-leakage test in the above manner, only one flow meter is required for the test, thereby reducing the number of components occupied during the test and improving the test efficiency of the single-cavity external leakage test and the multi-cavity cross-leakage test.

[0015] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 is a schematic structural diagram of an airtightness detection device provided in an exemplary embodiment of the present disclosure; Figure 2 is a flow chart of an airtightness detection method provided in an exemplary embodiment of the present disclosure, wherein: Figure 2 Represents the test method for fuel cell leakage; Figure 3 is a flow chart of another embodiment of the airtightness detection method provided in the exemplary embodiment of the present disclosure, wherein: Figure 3 Represents the test method for fuel cell cross-leakage.

[0017] Description of Reference Numerals 1-air supply module; 101-first air supply component; 102-second air supply component; 110-first air inlet pipeline; 2-flow test module; 210-flow test pipeline; 211-flow meter; 212-flow meter front valve; 213-flow meter rear valve; 220-bypass pipeline; 221-bypass valve; 3-external leakage test module; 301-external leakage valve; 310-first test pipe group; 311-first main pipe; 312-first branch pipe; 320-first valve group; 321-first stop valve; 330 -first external pipeline; 331-first exhaust valve; 4-leakage test module; 410-second test tube group; 411-leakage valve; 412-second main pipe; 413-second branch pipe; 420-second valve group; 421-second stop valve; 430-third valve group; 431-third stop valve; 440-second external pipeline; 441-second exhaust valve; 450-second air intake pipeline; 451-second air intake branch; 5-cavity; 501-cavity; 502-hydrogen chamber; 503-cold chamber. DETAILED DESCRIPTION

[0018] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0019] In the present disclosure, unless otherwise specified, directional words such as "inside" and "outside" refer to the inside and outside relative to the outline of the structure or component itself; "first, second" and the like are intended to distinguish one element from another and have no order or importance. In addition, the same figure marks in different reference drawings represent the same elements.

[0020] In a first aspect of the present disclosure, there is provided an airtight detection device, referring to Figure 1 As shown, the airtightness detection device can be used to perform airtightness detection on a fuel cell. The fuel cell includes a plurality of cavities 5. The airtightness detection device includes a gas supply module 1, a flow test module 2, an external leakage test module 3 and a cross-leakage test module 4, wherein the flow test module 2 is connected to the outlet of the gas supply module 1 through a first air inlet pipeline 110, the flow test module 2 includes a flow test pipeline 210 and a bypass pipeline 220, a flow meter 211 is provided on the flow test pipeline 210, and a bypass valve 221 is provided on the bypass pipeline 220; The test module 3 includes a first test tube group 310 and an external leakage valve 301 located on the first air intake pipeline 110, one end of the first test tube group 310 is connected to the flow test module 2; the other end is used to be connected to multiple cavities 5 through the first valve group 320; the leakage test module 4 includes a second test tube group 410, and the second test tube group 410 is provided with a second valve group 420. One end of the second test tube group 410 is connected to the multiple cavities 5 through the second valve group 420, and the other end is connected to the flow test module 2.

[0021] By means of the above technical solution, that is, by means of the airtight detection device provided by the present invention, when the fuel cell is subjected to airtight detection, a single-chamber leakage test and a multi-chamber leakage test can be respectively performed on the fuel cell through only one flow meter 211, that is, when performing a single-chamber leakage test, the bypass valve 221 and the leakage valve 301 can be opened, and the multiple cavities 5 of the fuel cell can be inflated through the bypass pipeline 220 using the gas supply module 1, and after the gas is inflated to a preset pressure so that the internal pressure of the multiple cavities 5 tends to be stable, the flow test pipeline 210 of the flow test module 2 is inflated through the gas supply module 1, and the flow test pipeline 210 located at the flow meter 211 is inflated to a preset pressure. When the pipeline pressures before and after the flowmeter 211 tend to be stable, the value of the flowmeter 211 is reset to zero, and after a preset period of time, the leakage of the multiple chambers 5 is determined by observing the measured instantaneous flow of the flowmeter 211. That is, it can be understood that if there is leakage, the previously inflated gas will leak out from the leakage points of the multiple chambers 5, and as the gas is discharged and the air pressure gradually decreases, the instantaneous flow displayed by the flowmeter 211 will increase, thereby determining that the multiple chambers 5 of the fuel cell have leakage; when performing a multi-chamber leakage test, the second valve group 420 connected to the second valve group 420 can be opened first. The valve of a cavity 5 is opened, and the cavity 5 is inflated through the air supply module 1. When the air pressure of one of the cavities 5 meets the preset pressure and tends to be stable, the valve in the second valve group 420 connected to another cavity 5 is opened, and the pipelines of the flow test pipeline 210 located before the flow meter 211 and after the flow meter 211 are inflated through the air supply module 1. After the pressure tends to be stable, the flow meter 211 is reset to zero, and after standing for a preset time, the actual measured instantaneous flow of the flow meter 211 is observed to determine the leakage between any two cavities 5 in the multiple cavities 5. That is, it can be understood that if there is a leakage, the previous The gas used to inflate the other cavity 5 will leak outward, and as the gas is discharged outward and the air pressure gradually decreases, the instantaneous flow rate displayed by the flow meter 211 will increase, thereby determining that there is a cross-leakage between the above two cavities 5. When the instantaneous flow rate displayed by the flow meter 211 is zero, it means that there is no cross-leakage between the above two cavities 5. When the fuel cell is subjected to a single-cavity external leakage test and a multi-cavity cross-leakage test in the above manner, only one flow meter 211 is required for the test, thereby reducing the number of components occupied during the test and improving the test efficiency of the single-cavity external leakage test and the multi-cavity cross-leakage test.

[0022] It should be noted that, when the above-mentioned airtightness test is performed on the fuel cell, the specific number of the cavities 5 can be any number of two or more than two, such as three, four, five or more. The above-mentioned airtightness test device can be used to test the airtightness of a multi-cavity fuel cell. Figure 1As shown, the present disclosure exemplarily constructs the fuel cell as a hydrogen fuel cell, and the multiple cavities 5 may include an empty cavity 501, a hydrogen cavity 502 and a cold cavity 503. Through the airtight detection device, the three cavities of the empty cavity 501, the hydrogen cavity 502 and the cold cavity 503 of the hydrogen fuel cell can be respectively subjected to a single-cavity external leakage test, and the three cavities of the empty cavity 501, the hydrogen cavity 502 and the cold cavity 503 can also be subjected to a multi-cavity cross-leakage test, for example, a multi-cavity cross-leakage test from air to hydrogen, hydrogen to air, empty to cold, cold to air, hydrogen to cold, and cold to hydrogen can be included.

[0023] In addition, in the above specific embodiment, the second test tube group 410 is respectively connected between the external leakage valve 301 and the flow meter 211, and between the external leakage valve 301 and the bypass valve 221, that is, it can be understood that when performing a single-chamber external leakage test, the flow meter 211 is located at the entrance of the airtight detection device for detection, and when performing a multi-chamber leakage test, the flow meter 211 is located at the exit of the airtight detection device for detection. Through this combined arrangement, the number of components required for the airtight detection device when performing airtight detection on the fuel cell can be further reduced.

[0024] In some embodiments, reference Figure 1As shown, the first test tube group 310 includes a first main pipe 311 and three first branch pipes 312. The first main pipe 311 is connected to the cavity 501, the hydrogen chamber 502 and the cold chamber 503 through the three first branch pipes 312. The first valve group 320 includes three first stop valves 321. The first stop valves 321 are arranged in the first branch pipes 312 one by one. In this way, the three first stop valves 321 can be opened or closed to allow or prevent the gas from the gas supply module 1 from entering the cavity 501, the hydrogen cavity 502 and the cold cavity 503, so that the three cavities 5 can be tested for leakage at the same time or two of the three cavities 5 or a single cavity can be tested for leakage. For example, when the three cavities 5 are tested for leakage and the problem is checked, the three first stop valves 321 on the three first branch pipes 312 can be opened, and the cavity 501, the hydrogen cavity 502 and the cold cavity 503 can be inflated through the gas supply module 1 to perform a leakage test on the three cavities. If leakage occurs, any two of the three cavities can be tested again. For example, For example, the two first stop valves 321 on the two first branch pipes 312 connecting the cavity 501 and the hydrogen cavity 502 are opened, and the cavity 501 and the hydrogen cavity 502 are inflated to perform a leakage test again. If there is no leakage in the cavity 501 and the hydrogen cavity 502, it can be determined that the cold cavity 503 has leaked. If there is leakage in the cavity 501 and the hydrogen cavity 502, the two first stop valves 321 on the two first branch pipes 312 connecting the cavity 501 and the hydrogen cavity 502 are opened again, and the cavity 501 and the hydrogen cavity 502 are inflated again through the gas supply module 1 to determine the specific cavity where the leakage occurs. Through the above-mentioned narrowed range test method, the specific location of the leakage can be quickly determined when performing a single cavity leakage test.

[0025] In some embodiments, reference Figure 1As shown, the second test tube group 410 includes a second main pipe 412 and three second branch pipes 413. The second main pipe 412 is connected to the cavity 501, the hydrogen chamber 502 and the cold chamber 503 through the three second branch pipes 413. A leakage valve 411 is provided on the second main pipe 412, and the outlet of the second main pipe 412 is connected to the flow test module 2. The second valve group 420 includes three second stop valves 421, and the second stop valves 421 are arranged one by one on the second branch pipes 413. In this way, the three second stop valves 421 can be opened or closed to allow or prevent the gas from the gas supply module 1 from being discharged from the cavity 501, the hydrogen cavity 502 and the cold cavity 503 to the flow meter 211, so as to facilitate the multi-cavity leakage test. For example, when performing the leakage test from the cavity 501 to the hydrogen cavity 502, the second stop valve 421 on the second branch pipe 413 connected to the cavity 501 can be opened first, and the second branch pipe 413 and the second main pipe 412 can be inflated through the gas supply module 1. After the gas pressure in the second branch pipe 413 and the second main pipe 412 tends to be stable, the leakage valve 411 is opened, and the flow test pipeline 210 before and after the flow meter 211 is also inflated and the gas pressure is inflated to a stable level, and then the second stop valve 421 connected to the hydrogen cavity 502 can be opened. The second stop valve 421 on the second branch pipe 413 of 02 can judge the leakage from the cavity 501 to the hydrogen cavity 502 by the flow rate through the hydrogen cavity 502 along the second branch pipe 413, the second main pipe 412 and input to the flow meter 211. For details, please refer to the above-mentioned embodiment, that is, when the flow rate displayed by the flow meter 211 is zero, it means that there is no cross-leakage from the cavity 501 to the hydrogen cavity 502. When the instantaneous flow rate displayed by the flow meter 211 is not zero but increases, it means that there is cross-leakage from the cavity 501 to the hydrogen cavity 502, and the hydrogen fuel cell needs to be repaired. Similarly, the cross-leakage test of other cavities such as hydrogen to air, air to cold, cold to air, hydrogen to cold, cold to hydrogen mentioned in the above-mentioned specific embodiment can also be tested in the above-mentioned way, and the present disclosure will not elaborate on this.

[0026] In some embodiments, reference Figure 1 As shown, the leakage test module 4 also includes a third valve group 430 and a second air intake pipeline 450. The second air intake pipeline 450 includes a second air intake branch 451 respectively connected to the air supply module 1 and each chamber 5; the third valve group 430 includes a third stop valve 431 respectively arranged on each second air intake branch 451. In this way, when performing a multi-cavity leakage test, the multi-cavity leakage test can be performed by opening one or more third stop valves 431 and inflating one or more second air intake branches 451 through the air supply module 1.

[0027] In some embodiments, reference Figure 1As shown, the flow test module 2 also includes a flow meter front valve 212 and a flow meter rear valve 213. The flow meter front valve 212 is arranged in the flow test pipeline 210 and is located upstream of the flow meter 211; the flow meter rear valve 213 is arranged in the flow test pipeline 210 and is located downstream of the flow meter 211. In this way, the flow meter front valve 212 and the flow meter rear valve 213 can be closed when the flow meter 211 is not in use, so that the staff can reset the value of the flow meter 211 and perform maintenance operations. In combination with the single-cavity leakage test of the above-mentioned embodiment, after the bypass pipeline 220 of the fuel cell is inflated until the internal pressure of the multiple cavities 5 tends to be stable through the gas supply module 1, the flow meter front valve 212 and the flow meter rear valve 213 are opened to inflate the flow test pipeline 210 through the gas supply module 1. On the other hand, when combining the multi-chamber leakage test in the above-mentioned embodiment, one of the cavities 5 (for example, the cavity 501) can be inflated in the gas supply module 1 and after the gas pressure meets the preset pressure and tends to be stable, the valve connected to another cavity 5 (for example, the hydrogen chamber 502) in the second valve group 420 and the flowmeter front valve 212 and the flowmeter rear valve 213 are opened at the same time to judge whether a leakage occurs by the gas flow discharged into the flowmeter 211 through the hydrogen chamber 502 along the second branch pipe 413 and the second main pipe 412.

[0028] In some embodiments, reference Figure 1 As shown, the leakage test module 3 further includes a first external discharge pipeline 330 connected to the flow test module 2 and the first test tube group 310, and a first exhaust valve 331 is provided on the first external discharge pipeline 330; and / or, the cross-talk test module 4 further includes a second external discharge pipeline 440 connected to the second test tube group 410, and a second exhaust valve 441 is provided on the second external discharge pipeline 440. In this way, the first external discharge pipeline 330 can discharge the gas remaining in the pipeline at the end of the single-chamber leakage test, that is, it can refer to Figure 1 As shown, at the end of the single-chamber leakage test, there is residual gas in the first air inlet pipeline 110, the flow test pipeline 210, the bypass pipeline 220 and the first test tube group 310. At this time, the first exhaust valve 331 can be opened, and the residual gas in each pipeline can be discharged to the outside through the first external exhaust pipeline 330, thereby reducing the influence of the residual gas in the pipeline on the inaccurate measurement results of other subsequent test methods, such as the flow meter 211 measuring the number does not conform to the actual situation; similarly, refer to Figure 1 As shown, at the end of the multi-cavity leakage test, there will be residual gas in the second test tube group 410 and the flow test pipeline 210. The second exhaust valve 441 can be opened to discharge the residual gas to the outside through the second external exhaust pipeline 440. This can also reduce the impact of inaccurate measurement results caused by residual gas in the pipeline on subsequent other test methods.

[0029] It should be noted that, in the above-mentioned embodiment, the first external exhaust pipe 330 can also be exhausted to the outside after both the single-chamber external leakage test and the multi-chamber cross leakage test are completed, but the first external exhaust pipe 330 is far away from the cross leakage test module 4. In order to exhaust all the residual gas in the pipe as much as possible, at the end of the multi-chamber cross leakage test, the second external exhaust pipe 440 closer to the cross leakage test module 4 can usually be selected to exhaust the residual gas.

[0030] In some embodiments, reference Figure 1 As shown, the gas supply module 1 includes a first gas supply member 101 and a second gas supply member 102, and the gas supply pressure of the first gas supply member 101 is higher than the gas supply pressure of the second gas supply member 102. In this way, when performing a single-cavity leakage test and a multi-cavity leakage test, the first gas supply member 101 and the second gas supply member 102 with different gas supply pressures can be used respectively, because there is a proton exchange membrane between any two cavities of the cavity 501, the hydrogen cavity 502 and the cold cavity 503 of the hydrogen fuel cell, and one of the important reasons for the multi-cavity leakage is the rupture of the proton exchange membrane between the two cavities, therefore, when performing a single-cavity leakage test, the first gas supply member 101 with a higher gas supply pressure can be used, and when performing a multi-cavity leakage test, in order to avoid further damage to the proton exchange membrane due to excessive gas supply pressure, the second gas supply member 102 with a lower gas supply pressure can be used. In the present disclosure, the gas supply pressure of the first gas supply member 101 can be 200Kpa, and the gas supply pressure of the second gas supply member 102 can be 50Kpa.

[0031] In a second aspect of the present disclosure, a gas-tightness detection method is provided for leak detection of a fuel cell. The method can be implemented using the gas-tightness detection device in the above specific embodiment. Figure 2 As shown, the method includes: S1, opening the external leakage valve and the bypass valve, and the gas supply module inflates the multiple cavities of the fuel cell to a first preset pressure through the bypass pipeline along the first test tube group.

[0032] Through the above step S1, i.e., the multiple cavities 5 of the fuel cell are inflated through the bypass line 220 by the gas supply module 1, so that the multiple cavities 5 can be inflated to a preset pressure and become stable, which is convenient for subsequent single-cavity leakage detection.

[0033] S2, after the flow test pipeline is inflated to a first preset pressure through the air supply module, the bypass valve is closed.

[0034] Through the above-mentioned S2 step, that is, the pressure in the flow test pipeline 210 is also charged to the first preset pressure through the gas supply module 1. In the subsequent single-cavity leakage detection process, if a single-cavity leakage occurs, the gas in the cavity 5 will be discharged to the outside, and the pressure in the flow test pipeline 210 will also decrease. As the pressure decreases, the instantaneous flow through the flow meter 211 will also increase, so that it can be determined that a single-cavity leakage occurs. Specifically, in the above-mentioned S1 step, the flow meter front valve 212 and the flow meter rear valve 213 are in a closed state, and in the S2 step, the flow meter front valve 212 and the flow meter rear valve 213 need to be opened to stabilize the air pressure in the flow test pipeline 210.

[0035] S3, after standing for a first preset time, obtaining a first measured flow rate of the flow meter.

[0036] Through the above-mentioned S3 step, that is, by obtaining the first measured flow of the flow meter after standing for the first preset time, it can be determined whether a single-cavity leakage has occurred in the fuel cell. That is, if the first measured flow is not zero, it can be considered that a single-cavity leakage has occurred in the fuel cell, and the problem can be troubleshooted by referring to the above-mentioned single-cavity leakage method, that is, the operations of simultaneously detecting three cavities, simultaneously detecting two cavities and finally detecting a single cavity. If the first measured flow is zero, it is considered that no single-cavity leakage has occurred.

[0037] The above steps S1 to S3 are all testing methods for single-cavity leakage testing.

[0038] In some embodiments, reference Figure 3 As shown, the method also includes: S4, opening the bypass valve, and the gas supply module inflates at least one of the multiple chambers of the fuel cell to a second preset pressure.

[0039] Through the above-mentioned S4 step, that is, inflating one cavity among the multiple cavities through the gas supply module 1, for example, taking the leakage test from air to hydrogen as an example, this step can be regarded as inflating the cavity 501 through the second gas supply part 102 of the gas supply module 1. In this process, the second stop valve 421 on the second branch pipe 413 connected to the cavity 501 can be opened, and the leakage valve 411 on the second main pipe 412 can be opened. When one of the second branch pipes 413 and the second main pipe 412 reaches the second preset pressure, the subsequent detection steps can be started.

[0040] S5, at least partially opening the second valve group, and after the other two of the multiple chambers inflate the flow test pipeline to a second preset pressure, closing the bypass valve.

[0041] Through the above-mentioned S5 step, one of the other two of the multiple chambers is inflated. For example, taking the leakage test from air to hydrogen as an example, after the cavity has been inflated in the above-mentioned step, the second stop valve 421 on the second branch pipe 413 connected to the hydrogen chamber 502 can be opened in this step. After the second branch pipe 413 connected to the hydrogen chamber 502 is also inflated to the second preset pressure, the bypass valve 221 can be closed to facilitate the observation of the subsequent flow meter 211 count.

[0042] S6, after standing for a second preset time, obtaining a second measured flow rate of the flow meter.

[0043] Through the above-mentioned step S6, that is, by observing the count of the flow meter 211, the specific situation of multi-cavity leakage can be determined. When the instantaneous flow detected by the flow meter 211 is zero, it is determined that there is no multi-cavity leakage. If the instantaneous flow detected by the flow meter 211 is not zero and has an increasing trend, it can be determined that there is leakage from the cavity to the hydrogen cavity.

[0044] The above steps S4 to S6 are all multi-chamber leakage testing methods, and in the above steps S4 to S6, they can also be used for multi-chamber leakage testing of hydrogen fuel cells from hydrogen to air, air to cold, cold to air, hydrogen to cold, and cold to hydrogen.

[0045] In a specific embodiment, the present disclosure is exemplified by a single-cavity leakage test. In the single-cavity leakage test, the following steps may be mainly included: Open the leakage valve 301, the bypass valve 221, and the three first stop valves 321 on the three first branch pipes 312 corresponding to the cavity 501, the hydrogen cavity 502, and the cold cavity 503, and fill the cavity 501, the hydrogen cavity 502, and the cold cavity 503 with high-pressure gas (e.g., 200 KPa) through the first gas supply member 102 of the gas supply module 1 along the first gas inlet pipeline 110, the bypass pipeline 220, the first main pipe 311, and the three first branch pipes 312. After the pressure in the three cavities is respectively filled to the first preset pressure, open the flow meter front valve 212 and the flow meter front valve 213. After the pressure in the flow test pipeline 210 is also filled to the first preset pressure through the first air supply member 102, the bypass valve 221 is closed and the flow meter 211 is reset to zero. After standing for a first preset time, it is determined whether the three chambers are leaking by observing the value displayed by the flow meter 211. When there is leakage in the three chambers, the gas previously inflated in the flow test pipeline 210 will leak out from the leakage of the three chambers. As the gas is discharged outward, the air pressure in the flow test pipeline 210 will gradually decrease, and the flow meter 2 11 In the case of pressure fluctuation, the displayed instantaneous flow rate will increase, which can be used to determine that one or more of the three chambers have leaked. In this case, the first stop valve 321 on one of the first branch pipes 312 can be closed, for example, the first stop valve 321 on the first branch pipe 312 connected to the cold chamber 503 can be closed, and the above steps are repeated to perform leakage tests on the cavity 501 and the hydrogen chamber 502. If the instantaneous flow rate displayed by the flow meter 211 is zero, it proves that there is no leakage in the cavity 501 and the hydrogen chamber 502, and there is leakage in the cold chamber 503. Leakage: If the instantaneous flow rate displayed by the flow meter 211 is still not zero or increasing, it proves that leakage has occurred in the cavity 501 or the hydrogen cavity 502. At this time, the first stop valve 321 on the first branch pipe 312 connected to the cavity 501 can be closed, or the first stop valve 321 on the first branch pipe 312 connected to the hydrogen cavity 502 can be closed to perform separate leakage detection on the cavity 501 and the hydrogen cavity 502 respectively. After the test is completed, the first exhaust valve 331 can be opened to discharge the residual gas in the pipeline through the first external exhaust pipeline 330.

[0046] In a specific embodiment, the present disclosure exemplarily uses a multi-cavity cross-leakage test from the cavity 501 to the hydrogen cavity 502 as an example, which can mainly include the following steps: The second stop valve 421, the leakage valve 411 and the bypass valve 221 on the second branch pipe 413 connected to the cavity 501 are opened, and the cavity 501 and the second branch pipe 413, the second main pipe 412 and the bypass pipe 220 connected to the cavity 501 are inflated through the second gas supply member 102 of the gas supply module 1. After the gas is inflated to the second preset pressure, the bypass valve 221 is closed, the second stop valve 421 on the second branch pipe 413 connected to the hydrogen chamber 502 is opened, and the flow meter front valve 212 and the flow meter front valve 220 are opened. After the meter is closed, valve 213 is closed and left to stand for a second preset time, and then the second measured flow rate displayed by flow meter 211 is observed, that is, the real-time instantaneous flow rate displayed by flow meter 211. When the flow rate value displayed by flow meter 211 is zero, it can be proved that there is no leakage from cavity 501 to hydrogen cavity 502. If flow meter 211 displays flow, it can be proved that there is leakage from cavity 501 to hydrogen cavity 502. After the cross-leakage inspection is completed, the second exhaust valve 441 can be opened to discharge the residual gas to the outside.

[0047] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0048] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0049] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. An airtightness detection device for performing airtightness detection on a fuel cell, wherein the fuel cell comprises a plurality of cavities, characterized in that: The airtight detection device comprises: Air supply module; A flow test module, connected to the outlet of the air supply module through a first air inlet pipeline, the flow test module comprising a flow test pipeline and a bypass pipeline, the flow test pipeline is provided with a flow meter, and the bypass pipeline is provided with a bypass valve; An external leakage test module, comprising a first test tube group and an external leakage valve located on the first air inlet pipeline, wherein one end of the first test tube group is connected to the flow test module; and the other end is connected to the plurality of cavities through a first valve group in an on-off manner; and The cross-talk test module comprises a second test tube group, on which a second valve group is provided, one end of which is connected to the plurality of cavities in an on-off manner through the second valve group, and the other end of which is connected to the flow test module.

2. The airtight detection device according to claim 1, characterized in that: The fuel cell is configured as a hydrogen fuel cell, and the plurality of chambers include an air chamber, a hydrogen chamber, and a cold chamber.

3. The airtight detection device according to claim 2, characterized in that: The first test tube group includes a first main pipe and three first branch pipes, and the first main pipe is connected to the cavity, the hydrogen chamber and the cold chamber one by one through the three first branch pipes; The first valve group includes three first stop valves, and the first stop valves are arranged in a one-to-one correspondence on the first branch pipe.

4. The airtight detection device according to claim 2, characterized in that: The second test tube group includes a second main pipe and three second branch pipes, the second main pipe is connected to the cavity, the hydrogen chamber and the cold chamber one by one through the three second branch pipes; a leakage valve is provided on the second main pipe, and the outlet of the second main pipe is connected to the flow test module; The second valve group includes three second stop valves, and the second stop valves are arranged in a one-to-one correspondence on the second branch pipes.

5. The airtight detection device according to claim 4, characterized in that: The leakage test module also includes a third valve group and a second air intake pipeline, wherein the second air intake pipeline includes a second air intake branch respectively connected to the air supply module and each of the cavities; the third valve group includes a third stop valve respectively arranged on each of the second air intake branches.

6. The airtight detection device according to claim 1, characterized in that: The flow test module also includes: A flow meter front valve, provided in the flow test pipeline and located upstream of the flow meter; and The flow meter rear valve is arranged in the flow test pipeline and is located downstream of the flow meter.

7. The airtight detection device according to claim 1, characterized in that: The leakage test module further comprises a first external exhaust pipeline connected to the flow test module and the first test tube group, and a first exhaust valve is disposed on the first external exhaust pipeline; and / or The cross-talk test module further includes a second external exhaust pipeline connected to the second test tube group, and a second exhaust valve is provided on the second external exhaust pipeline.

8. The airtight detection device according to claim 1, characterized in that: The air supply module includes a first air supply member and a second air supply member, and the air supply pressure of the first air supply member is higher than the air supply pressure of the second air supply member.

9. A gas-tightness detection method for leak detection of a fuel cell, characterized in that: The method adopts the airtightness detection device according to any one of claims 1 to 8, and the method comprises: The external leakage valve and the bypass valve are opened, and the gas supply module inflates the multiple cavities of the fuel cell to a first preset pressure through the bypass pipeline along the first test tube group; After the flow test pipeline is inflated to the first preset pressure through the air supply module, the bypass valve is closed; After standing for a first preset time, a first measured flow rate of the flow meter is obtained.

10. The method according to claim 9, characterized in that The method further comprises: The bypass valve is opened, and the gas supply module inflates at least one of the multiple chambers of the fuel cell to a second preset pressure; At least partially opening the second valve group, after one of the other two of the plurality of chambers inflates the flow test pipeline to the second preset pressure, closing the bypass valve; After standing for a second preset time, a second measured flow rate of the flow meter is obtained.

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