Fuel cell air tightness detection device

Abstract

The utility model relates to the field of air tightness detection, and discloses a fuel cell air tightness detection device which is suitable for executing all existing known air tightness detection items by arranging an air inlet system, a rapid inflation system, a flow detection system, a branch test system and an exhaust system and setting all switch valves to be capable of being opened and closed independently. And the method has extremely high universality and detection convenience. Moreover, compared with some existing air tightness detection equipment which is additionally provided with a large number of sensors in order to execute more air tightness detection items and is relatively complex in overall structure, the air tightness detection equipment has the advantages that the air path structure is effectively simplified, the cost can be saved, and the disassembly and assembly of the device and the fuel cell are facilitated. In addition, the rapid inflation system can improve the inflation speed of the fuel cell during detection, and the detection efficiency can be effectively improved. In addition, the device can be used for measuring the volume of a single cavity of the fuel cell, so that the function of the device can be further expanded.

Description

Technical Field

[0001] The present application belongs to the technical field of air tightness detection, and specifically relates to an air tightness detection device for a fuel cell. Background Art

[0002] With the development of the fuel cell industry, more and more special equipment is available for fuel cells. The air tightness test of fuel cells has also evolved from the initial pressure test to the current coexistence of multiple test methods such as leakage test and pressure test. Special air tightness test equipment for fuel cell bipolar plates, membrane electrodes, and stacks has also begun to be developed. The special air tightness test equipment for fuel cells has been gradually improved, and some air tightness test equipment with different focuses has been developed, such as focusing on rapid disassembly and assembly of pipelines to meet efficiency requirements, adding temperature control boxes to meet testing requirements at different temperatures, and simplifying as much as possible to meet economic requirements.

[0003] The current focus of airtightness testing of fuel cell stacks and systems is on solving problems such as testing convenience and efficiency. However, for comprehensive airtightness testing needs, a large number of sensors need to be used, resulting in a more complex equipment structure and higher costs. Utility Model Content

[0004] The purpose of the present application is to provide a fuel cell air tightness detection device, which can simplify the gas path structure, reduce costs, and improve detection efficiency on the basis of being able to perform all fuel cell air tightness detection items.

[0005] In order to achieve the above-mentioned object, the present application provides a fuel cell air tightness detection device, which comprises:

[0006] An air intake system is provided with a total air intake pipeline and a total pressure sensor connected in series in the total air intake pipeline;

[0007] A fast-charging system, comprising a fast-charging pipeline and a fast-charging switch valve connected in series in the fast-charging pipeline;

[0008] A flow detection system, comprising a flow detection main circuit, a first flow detection branch circuit and a second flow detection branch circuit, wherein a first branch detection switch valve is connected in series in the first flow detection branch circuit, a second branch detection switch valve is connected in series in the second flow detection branch circuit, and the first main circuit detection switch valve, a flow meter and a second main circuit detection switch valve are connected in series in the flow detection main circuit in the direction of the inflation airflow;

[0009] A branch test system is provided with a plurality of test branches, each of which is serially connected with a test switch valve, a branch pressure sensor and a battery connector in sequence along the direction of the inflation airflow; and

[0010] An exhaust system, comprising a main exhaust pipeline and a plurality of exhaust branches respectively arranged corresponding to the plurality of test branches, each of the exhaust branches being serially connected with a branch exhaust switch valve, and the main exhaust pipeline being serially connected with a main exhaust switch valve;

[0011] Among them, along the direction of the inflation airflow, the fast charging pipeline and the flow detection main road are connected in parallel to the downstream end of the total intake pipeline and the upstream ends of multiple test branches; one end of the first flow detection branch is connected to the pipe section of the flow detection main road located between the first main road detection switch valve and the flow meter, and the other end is connected to the pipe section of the total exhaust pipeline located upstream of the total exhaust switch valve; one end of the second flow detection branch is connected to the pipe section of the flow detection main road located between the flow meter and the second main road detection switch valve, and the other end is connected to the pipe section of the total exhaust pipeline located downstream of the total exhaust switch valve; the downstream end of each of the exhaust branches is connected to the upstream end of the total exhaust pipeline, and the upstream end of each of the exhaust branches is connected to the pipe section of the corresponding test branch located between the test switch valve and the branch pressure sensor; all the switch valves in the fuel cell air tightness detection device are independently switched.

[0012] In some embodiments, the fuel cell air tightness detection device includes a single chamber pressure holding test condition;

[0013] In the inflation phase of the single-chamber pressure-maintaining test condition, the main air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0014] During the test phase of the single-chamber pressure-maintaining test condition, any one of the test branches is switched to a cut-off state.

[0015] In some embodiments, the fuel cell air tightness detection device includes a full-cavity pressure-maintaining test condition;

[0016] In the inflation phase of the full-cavity pressure-maintaining test condition, the total air intake pipeline, the fast-charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0017] During the test phase of the full-cavity pressure-maintaining test condition, all of the test branches are switched to a cut-off state.

[0018] In some embodiments, the fuel cell air tightness detection device includes a single-chamber external leakage flow test condition;

[0019] In the inflation phase of the single-chamber external leakage flow test condition, the main air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0020] During the test phase of the single-chamber external leakage flow test condition, the total air intake pipeline, the flow detection main circuit and any one of the test branches are connected, and the remaining test branches are connected to the total exhaust pipeline through the correspondingly connected exhaust branches.

[0021] In some embodiments, the fuel cell air tightness detection device includes a full cavity external leakage flow test condition;

[0022] In the inflation phase of the full-cavity external leakage flow test condition, the total air intake pipeline, the fast-charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0023] During the test phase of the full-cavity external leakage flow test condition, the total air intake pipeline, the flow detection main circuit and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

[0024] In some embodiments, the fuel cell air tightness detection device includes a two-cavity crossflow flow test condition. Under the two-cavity crossflow flow test condition, the main intake pipeline, the fast charging pipeline and any one of the test branches are connected, and one of the remaining test branches is connected in sequence to the corresponding exhaust branch, the section of the main exhaust pipeline located upstream of the main exhaust switch valve, the first flow detection branch, the main flow detection branch, the second flow detection branch and the section of the main exhaust pipeline located downstream of the main exhaust switch valve.

[0025] In some embodiments, the fuel cell air tightness detection device includes a single-cavity to two-cavity crossflow test condition. Under the single-cavity to two-cavity crossflow test condition, the main intake pipeline, the fast charging pipeline and any one of the test branches are connected, and two of the remaining test branches are sequentially connected to the corresponding exhaust branches, the section of the main exhaust pipeline located upstream of the main exhaust switch valve, the first flow detection branch, the main flow detection branch, the second flow detection branch and the section of the main exhaust pipeline located downstream of the main exhaust switch valve.

[0026] In some embodiments, the fuel cell air tightness detection device includes a single chamber volume measurement mode;

[0027] In the first stage of the single-chamber volume measurement working condition, the total air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0028] In the second stage of the single-chamber volume measurement working condition, any one of the test branches is switched to a cut-off state, and any one of the test branches is sequentially connected to the corresponding exhaust branch, the pipe section of the total exhaust pipeline located upstream of the total exhaust switch valve, the first flow detection branch, the flow detection main road, the second flow detection branch, and the pipe section of the total exhaust pipeline located downstream of the total exhaust switch valve;

[0029] In the third stage of the single-chamber volume measurement working condition, all the battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as those in the first stage;

[0030] In the fourth stage of the single-chamber volume measurement condition, all the battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as those in the second stage.

[0031] In some embodiments, the fuel cell air tightness detection device includes a battery full-cavity pressure relief condition. Under the battery full-cavity pressure relief condition, each of the test branches is in a cut-off state and is sequentially connected to the corresponding exhaust branch and the main exhaust pipeline.

[0032] In some embodiments, the fuel cell air tightness detection device includes a pressure relief condition at the front end of the device. Under the pressure relief condition at the front end of the device, the total air intake pipeline, the fast charging pipeline, the second flow detection branch and the total exhaust pipeline are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

[0033] The fuel cell air tightness detection device of the present application is provided with an intake system, a fast inflation system, a flow detection system, a branch test system, an exhaust system, and all the switch valves are set to be able to switch independently of each other. The switch state of each switch valve can be adjusted to switch to the corresponding working condition according to the specific air tightness detection items to be performed, and it is suitable for performing all existing known air tightness detection items, and has extremely high versatility and detection convenience. Not only that, compared with some existing air tightness detection equipment that adds a large number of sensors in order to be able to perform more air tightness detection items, resulting in a more complex overall structure, the device of the present application effectively simplifies the gas path structure, especially reduces the number of flow meters, reduces the connection points with the fuel cell, thereby effectively saving costs and facilitating the disassembly and assembly of the device and the fuel cell. In addition, the fast inflation system can increase the inflation speed of the fuel cell during detection, which can effectively improve the detection efficiency. Furthermore, the fuel cell air tightness detection device of the present application can also perform single-chamber volume measurement on the fuel cell, which can further expand the function of the device.

[0034] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0036] Figure 1 This is a structural principle diagram of a fuel cell air tightness detection device in a specific implementation manner of the present application;

[0037] Figure 2 for Figure 1 A schematic diagram of a fuel cell air tightness detection device during the inflation phase of a single-chamber pressure-maintaining test condition;

[0038] Figure 3 for Figure 1 A schematic diagram of a fuel cell air tightness detection device during the inflation phase of a full-cavity pressure-maintaining test condition;

[0039] Figure 4 for Figure 1 A schematic diagram of a fuel cell air tightness detection device in a test phase of a single-chamber external leakage flow test condition;

[0040] Figure 5 for Figure 1 A schematic diagram of a fuel cell air tightness detection device in a test phase of a full-cavity external leakage flow test condition;

[0041] Figure 6 for Figure 1 Schematic diagram of the fuel cell air tightness detection device under the two-chamber cross-flow test condition;

[0042] Figure 7 for Figure 1 Schematic diagram of the fuel cell air tightness detection device under the condition of single-chamber to two-chamber crossflow test;

[0043] Figure 8 for Figure 1 A schematic diagram of a fuel cell air tightness detection device under a single-chamber volume measurement condition, wherein the first stage and the second stage (or the third stage and the fourth stage) of the single-chamber volume measurement condition are combined and displayed;

[0044] Fig. 9 for Figure 1 Schematic diagram of a fuel cell air tightness detection device under a battery full cavity pressure release condition;

[0045] Fig.10 for Figure 1 A schematic diagram of a fuel cell air tightness detection device in a pressure release condition at the front end of the device;

[0046] Description of Reference Numerals

[0047] 101 Air supply device 102 Main air intake switch valve

[0048] 103 Pressure reducer 104 Total pressure sensor

[0049] 201 Flow meter 211 First main line detection switch valve

[0050] 212 First branch detection switch valve 213 Second branch detection switch valve

[0051] 214 Second main circuit detection switch valve 301 Fast charging switch valve

[0052] 401 First test switch valve 402 Second test switch valve

[0053] 403 Third test switch valve 501 First branch pressure sensor

[0054] 502 Second branch pressure sensor 503 Third branch pressure sensor

[0055] 601 First connector 602 Second connector

[0056] 603 Third joint 701 First branch exhaust switch valve

[0057] 702 Second branch exhaust switch valve 703 Third branch exhaust switch valve

[0058] 801 Main exhaust switch valve DETAILED DESCRIPTION

[0059] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0060] Before introducing this application in detail, it is necessary to first explain that in this application Figures 1 to 10 In the figure, the pipeline marked with a bold line indicates that it is in a conducting state, and the airflow can flow through the pipeline at this time, while the pipeline marked with a thin line indicates that it is in a blocking state, and the airflow cannot flow through the pipeline at this time.

[0061] Reference Figure 1 The present application provides a fuel cell air tightness detection device, which is suitable for the air tightness detection of fuel cells with two or more cavities, such as a three-chamber fuel cell with a hydrogen chamber, an air chamber and a coolant chamber, or a two-chamber fuel cell with a hydrogen chamber and an air chamber.

[0062] The fuel cell air tightness detection device of the present application specifically includes:

[0063] The air intake system is provided with a total air intake pipeline and a total pressure sensor 104 connected in series in the total air intake pipeline;

[0064] A fast-charging system, comprising a fast-charging pipeline and a fast-charging switch valve 301 connected in series in the fast-charging pipeline;

[0065] The flow detection system is provided with a flow detection main circuit, a first flow detection branch circuit and a second flow detection branch circuit, wherein a first branch detection switch valve 212 is connected in series in the first flow detection branch circuit, a second branch detection switch valve 213 is connected in series in the second flow detection branch circuit, and a first main circuit detection switch valve 211, a flow meter 201 and a second main circuit detection switch valve 214 are connected in series in the flow detection main circuit in the direction of the inflation airflow;

[0066] A branch test system is provided with a plurality of test branches, each of which is serially connected with a test switch valve, a branch pressure sensor and a battery connector in sequence along the direction of the inflation airflow; and

[0067] The exhaust system is provided with a main exhaust pipeline and a plurality of exhaust branches respectively corresponding to the plurality of test branches, each exhaust branch is connected in series with a branch exhaust switch valve, and the main exhaust pipeline is connected in series with a main exhaust switch valve 801;

[0068] Among them, along the direction of inflation airflow, the fast charging pipeline and the flow detection main road are connected in parallel to the downstream end of the main intake pipeline and the upstream ends of multiple test branches; one end of the first flow detection branch is connected to the pipe section of the flow detection main road located between the first main road detection switch valve 211 and the flow meter 201, and the other end is connected to the pipe section of the main exhaust pipeline located upstream of the main exhaust switch valve 801; one end of the second flow detection branch is connected to the pipe section of the flow detection main road located between the flow meter 201 and the second main road detection switch valve 214, and the other end is connected to the pipe section of the main exhaust pipeline located downstream of the main exhaust switch valve 801; the downstream end of each exhaust branch is connected to the upstream end of the main exhaust pipeline, and the upstream end of each exhaust branch is connected to the pipe section of the corresponding test branch between the test switch valve and the branch pressure sensor; all the switch valves in the fuel cell air tightness detection device are set to switch independently of each other.

[0069] Through the above-mentioned settings, the fuel cell air tightness detection device of the present application is provided with an intake system, a fast inflation system, a flow detection system, a branch test system, an exhaust system, and all the switch valves are set to be able to switch independently of each other, and the switch state of each switch valve can be adjusted according to the specific air tightness detection project to be performed to switch to the corresponding working condition, and is suitable for performing all existing known air tightness detection projects (a plurality of embodiments will be provided in detail later), and has extremely high versatility and detection convenience. Not only that, compared with some existing air tightness detection equipment that adds a large number of sensors in order to be able to perform more air tightness detection projects, resulting in a more complex overall structure, the device of the present application effectively simplifies the gas path structure, especially reduces the number of flow meters (only one flow meter 201 in the present application), and reduces the connection points with the fuel cell (because when performing different air tightness detection projects, it is only necessary to block the exhaust port of each cavity in the fuel cell, and the air inlet of each cavity only needs to be connected to a battery connector respectively for detection), thereby effectively saving costs and facilitating the disassembly and assembly of the device and the fuel cell. In addition, the fast inflation system can increase the inflation speed of the fuel cell during detection, which can effectively improve the detection efficiency. Furthermore, the fuel cell air tightness detection device of the present application can also perform single-chamber volume measurement on the fuel cell, which can further expand the function of the device.

[0070] As an example, refer to Figures 1 to 10 A fuel cell air tightness detection device is provided, wherein the detection device is provided with three test branches, wherein a first test switch valve 401, a first branch pressure sensor 501 and a first joint 601 are sequentially connected in series along the direction of the inflation air flow in the first test branch. A second test switch valve 402, a second branch pressure sensor 502 and a second joint 602 are sequentially connected in series along the direction of the inflation air flow in the second test branch. A third test switch valve 403, a third branch pressure sensor 503 and a third joint 603 are sequentially connected in series along the direction of the inflation air flow in the third test branch.

[0071] In addition, the fuel cell air tightness detection device is also provided with three exhaust branches, the first exhaust branch is connected to the first test branch and is connected in series with the first branch exhaust switch valve 701. The second exhaust branch is connected to the second test branch and is connected in series with the second branch exhaust switch valve 702. The third exhaust branch is connected to the third test branch and is connected in series with the third branch exhaust switch valve 703.

[0072] Furthermore, the air intake system of the fuel cell air tightness detection device can also be equipped with an air supply device 101 and a total air intake switch valve 102 and a pressure reducer 103. At this time, the exhaust end of the air supply device 101 is connected to the air intake end of the total air intake pipeline, and the total air intake switch valve 102, the pressure reducer 103 and the total pressure sensor 104 are sequentially connected in series in the total air intake pipeline along the direction of the inflation air flow.

[0073] Of course, the present application does not limit the number and composition of the test branches, exhaust branches, air intake system, etc. in the fuel cell air tightness detection device, and they can be adjusted according to actual needs.

[0074] The following is an introduction to all the air tightness detection items that can be performed by the fuel cell air tightness detection device of the present application. For the convenience of description, all operations in the following embodiments are performed after the fuel cell air tightness detection device is connected to the gas source and the connection point of the fuel cell to be tested (the air inlet of each cavity of the fuel cell), and no further description will be given later. In addition, before the test starts, all switch valves are closed by default.

[0075] In some embodiments, the fuel cell air tightness detection device includes a single-chamber pressure-maintaining test condition. In the inflation phase of the single-chamber pressure-maintaining test condition, the main air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; in the test phase of the single-chamber pressure-maintaining test condition, any one of the test branches is switched to a cut-off state.

[0076] by Figure 2 Taking the fuel cell air tightness detection device as an example, when performing a single-chamber pressure holding test on the battery chamber connected to the second connector 602, during the inflation stage, the total air intake switch valve 102, the fast charge switch valve 301 and the second test switch valve 402 are first opened to form a Figure 2 The gas path indicated by the bold line in the figure is set, and the intake pressure (determined by the total pressure sensor 104) is set, so as to quickly inflate the battery cavity connected to the second connector 602. After the pressure value displayed by the second branch pressure sensor 502 is stable, it means that the inflation is completed. At this time, the second test switch valve 402 is closed to enter the test phase, and the single cavity pressure holding test of the battery cavity connected to the second connector 602 is performed. The pressure change is recorded and transmitted by the second branch pressure sensor 502, for example, to the controller for subsequent analysis.

[0077] It should be noted that the above steps can be referred to when performing a single-chamber pressure test on the battery chamber connected to the first connector 601 or the battery chamber connected to the third connector 603. Similarly, the above steps can be referred to when performing a single-chamber pressure test on a fuel cell having two chambers.

[0078] In some embodiments, the fuel cell air tightness detection device includes a full-cavity pressure test condition. In the inflation phase of the full-cavity pressure test condition, the main air intake pipeline, the fast-charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; in the test phase of the full-cavity pressure test condition, all the test branches are switched to a cut-off state.

[0079] by Figure 3 Taking the fuel cell air tightness detection device as an example, when the three battery cavities connected to the first connector 601, the second connector 602 and the third connector 603 are respectively connected to the full cavity pressure test, in the inflation stage, the total air intake switch valve 102, the fast charge switch valve 301, the first test switch valve 401, the second test switch valve 402 and the third test switch valve 403 are first opened to form a Figure 3 The gas path indicated by the bold line in the figure is set, and the intake pressure (determined by the total pressure sensor 104) is set, so as to quickly inflate the three battery cavities. After the pressure values ​​displayed by the first branch pressure sensor 501, the second branch pressure sensor 502 and the third branch pressure sensor 503 are all stable, it means that the inflation is completed. At this time, the first test switch valve 401, the second test switch valve 402 and the third test switch valve 403 are closed, and the test phase can be entered to perform a full-cavity pressure-maintaining test on the three battery cavities. The pressure changes of the three cavities are recorded and transmitted by the first branch pressure sensor 501, the second branch pressure sensor 502 and the third branch pressure sensor 503, for example, to the controller for subsequent analysis.

[0080] It should be noted that when performing a full-cavity pressure-maintaining test on a fuel cell having two cavities, the above steps may be referred to.

[0081] In some embodiments, the fuel cell air tightness detection device includes a single-cavity external leakage flow test condition (the amount of gas leakage from a single cavity includes two parts, one part is the amount of internal gas between the tested battery cavity and the other battery cavities, and the other part is the amount of gas leaked from the tested battery cavity to the outside of the fuel cell). In the inflation phase of the single-cavity external leakage flow test condition, the total air intake line, the fast charging line and any one of the test branches are connected, and the remaining lines in the fuel cell air tightness detection device are in a cut-off state; in the test phase of the single-cavity external leakage flow test condition, the total air intake line, the flow detection main line and any one of the test branches are connected, and the remaining test branches are connected to the total exhaust line through the corresponding exhaust branches.

[0082] by Figure 4 Taking the fuel cell air tightness detection device as an example, when performing a single-cavity external leakage flow test on the battery cavity connected to the second connector 602, during the inflation stage, the total air intake switch valve 102, the fast charge switch valve 301 and the second test switch valve 402 are first opened to form Figure 2 The gas path marked with a bold line in the middle is set, and the intake pressure is set (determined by the total pressure sensor 104), so as to quickly inflate the battery cavity connected to the second connector 602. When the pressure value displayed by the second branch pressure sensor 502 stabilizes, it means that the inflation is completed. At this time, the fast charging switch valve 301 is closed, and the first main road detection switch valve 211, the second main road detection switch valve 214, the first branch exhaust switch valve 701, the third branch exhaust switch valve 703 and the total exhaust switch valve 801 are opened to form Figure 4 The gas path marked with a bold line can enter the test phase to conduct a single-cavity external leakage flow test on the battery cavity connected to the second connector 602. In this test phase, the pressure of the gas path is kept stable. At this time, the data displayed by the flow meter 201 is the gas leakage rate of the battery cavity connected to the second connector 602, and the data of the flow meter 201 can be transmitted to the outside, for example, to the controller for subsequent analysis.

[0083] It should be noted that when performing a single-cavity external leakage flow test on the battery cavity connected to the first connector 601 or the battery cavity connected to the third connector 603, the above steps can be referred to. Similarly, when performing a single-cavity external leakage flow test on a fuel cell with two cavities, the above steps can also be referred to.

[0084] In some embodiments, the fuel cell air tightness detection device includes a full-cavity leakage flow test condition. In the inflation phase of the full-cavity leakage flow test condition, the main air intake pipeline, the fast charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; in the test phase of the full-cavity leakage flow test condition, the main air intake pipeline, the flow detection main circuit and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

[0085] by Figure 5 Taking the fuel cell air tightness detection device as an example, when the three battery cavities connected to the first connector 601, the second connector 602 and the third connector 603 are respectively connected to the full cavity leakage flow test, in the inflation stage, the total air intake switch valve 102, the fast charge switch valve 301, the first test switch valve 401, the second test switch valve 402 and the third test switch valve 403 are first opened to form a Figure 3 The gas path marked with bold lines in the middle and the inlet pressure is set (determined by the total pressure sensor 104) to quickly inflate the three battery cavities. When the pressure values ​​displayed by the first branch pressure sensor 501, the second branch pressure sensor 502 and the third branch pressure sensor 503 are all stable, it means that the inflation is completed. At this time, the fast charging switch valve 301 is closed, and the first main detection switch valve 211 and the second main detection switch valve 214 are opened to form Figure 5 The gas path marked with a bold line can enter the test phase to conduct a full-cavity leakage flow test on the three battery cavities. In this test phase, the pressure of the gas path is kept stable. At this time, the data displayed by the flow meter 201 is the gas leakage rate of the three battery cavities, and the data of the flow meter 201 can be transmitted to the outside, for example, to the controller for subsequent analysis.

[0086] It should be noted that when performing a full-cavity leakage flow test on a fuel cell having two cavities, the above steps may also be referred to.

[0087] In some embodiments, the fuel cell air tightness detection device includes a two-chamber crossflow flow test condition. Under the two-chamber crossflow flow test condition, the main air intake line, the fast charging line and any one of the test branches are connected, and one of the remaining test branches is sequentially connected to the corresponding exhaust branch, the pipe section of the main exhaust line located upstream of the main exhaust switch valve 801, the first flow detection branch, the flow detection main line, the second flow detection branch and the pipe section of the main exhaust line located downstream of the main exhaust switch valve 801.

[0088] by Figure 6 Taking the fuel cell air tightness detection device as an example, when the battery cavity connected to the second connector 602 and the battery cavity connected to the first connector 601 are tested for cross-flow in the two cavities, the main air intake switch valve 102, the fast charge switch valve 301, the second test switch valve 402, the first branch exhaust switch valve 701, the first branch detection switch valve 212 and the second branch detection switch valve 213 are opened to form Figure 6 The gas path indicated by the bold line is used to adjust the gas pressure of the gas path. After the reading of the flow meter 201 is stable, the reading of the flow meter 201 is the blowby gas flow rate between the two battery cavities under test, and the data of the flow meter 201 can be transmitted to the outside, for example, to the controller for subsequent analysis.

[0089] It should be noted that when performing a cross-flow test between the battery cavity connected to the first connector 601 and the battery cavity connected to the third connector 603, or when performing a cross-flow test between the battery cavity connected to the second connector 602 and the battery cavity connected to the third connector 603, the above steps may be referred to. Similarly, when performing a cross-flow test between the two cavities of a fuel cell having two cavities, the above steps may also be referred to.

[0090] In some embodiments, the fuel cell air tightness detection device includes a single-chamber to two-chamber crossflow test condition. Under the single-chamber to two-chamber crossflow test condition, the main air intake line, the fast charging line and any one of the test branches are connected, and two of the remaining test branches are sequentially connected to the corresponding exhaust branch, the section of the main exhaust line located upstream of the main exhaust switch valve 801, the first flow detection branch, the main flow detection line, the second flow detection branch and the section of the main exhaust line located downstream of the main exhaust switch valve 801.

[0091] by Figure 7 Taking the fuel cell air tightness detection device as an example, when performing a single-chamber to two-chamber crossflow test from the battery cavity connected to the second joint 602 to the battery cavity connected to the first joint 601 and the battery cavity connected to the third joint 603, the total air intake switch valve 102, the fast charge switch valve 301, the second test switch valve 402, the first branch exhaust switch valve 701, the third branch exhaust switch valve 703, the first branch detection switch valve 212 and the second branch detection switch valve 213 are opened to form a Figure 7 The gas path indicated by the bold line is used to adjust the gas pressure of the gas path. After the reading of the flow meter 201 stabilizes, the reading of the flow meter 201 is the gas flow from the battery cavity connected to the second connector 602 to the battery cavity connected to the first connector 601 and the battery cavity connected to the third connector 603. The data of the flow meter 201 can be transmitted externally, for example, to the controller for subsequent analysis.

[0092] It should be noted that when conducting a single-cavity to two-cavity crossflow test from the battery cavity connected to the first connector 601 to the battery cavity connected to the second connector 602 and the battery cavity connected to the third connector 603, or when conducting a single-cavity to two-cavity crossflow test from the battery cavity connected to the third connector 603 to the battery cavity connected to the first connector 601 and the battery cavity connected to the second connector 602, the above steps can be referred to for execution.

[0093] In addition, it can be seen from the previous embodiments that the amount of gas leakage from a single cavity includes two parts, one part is the amount of internal crosstalk between the battery cavity under test and the remaining battery cavities, and the other part is the amount of gas leaked from the battery cavity under test to the outside of the fuel cell. Therefore, according to the single cavity external leakage flow data obtained by the single cavity external leakage flow test in the previous embodiment and the crosstalk flow data obtained by the single cavity to two cavity internal crosstalk flow test in this embodiment, the difference between the two sets of data is calculated, that is, the flow rate of the battery cavity under test leaking to the outside of the fuel cell is obtained. For example, by measuring the single cavity external leakage flow data of the battery cavity connected to the second connector 602, the internal crosstalk flow data from the battery cavity connected to the second connector 602 to the battery cavity connected to the first connector 601 and the battery cavity connected to the third connector 603, the difference between the two sets of data is calculated, that is, the flow rate of the battery cavity connected to the second connector 602 leaking to the outside of the fuel cell is obtained.

[0094] In some embodiments, the fuel cell air tightness detection device includes a single-cavity volume measurement mode, which can measure the volume of a battery cavity of unknown volume.

[0095] In the first stage of the single-chamber volume measurement condition, the main air intake pipeline, the fast-charging pipeline and any test branch are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state;

[0096] In the second stage of the single-chamber volume measurement condition, any one of the test branches is switched to the cut-off state, and any one of the test branches is sequentially connected to the corresponding exhaust branch, the pipe section of the total exhaust pipeline located upstream of the total exhaust switch valve 801, the first flow detection branch, the flow detection main road, the second flow detection branch, and the pipe section of the total exhaust pipeline located downstream of the total exhaust switch valve 801;

[0097] In the third stage of the single-chamber volume measurement condition, all battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as in the first stage;

[0098] In the fourth stage of the single-chamber volume measurement condition, all battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as in the second stage.

[0099] by Figure 8 Taking the fuel cell air tightness detection device as an example, the single cavity volume of the battery cavity connected to the second connector 602 is measured. In the first stage, the total air intake switch valve 102, the fast charge switch valve 301 and the second test switch valve 402 are opened to quickly inflate the battery cavity connected to the second connector 602, and the second stage is entered after the pressure stabilizes.

[0100] In the second stage, the second test switch valve 402 is closed, and the second branch exhaust switch valve 702, the first branch detection switch valve 212, and the second branch detection switch valve 213 are opened to release gas from the battery cavity connected to the second connector 602. After the pressure value displayed by the second branch pressure sensor 502 drops to zero, V is calculated based on the gas flow rate flowing through the flow meter 201 in the second stage. 总 ,,The V 总 It is the sum of the volumes of the second test branch and the battery cavity connected to the second connector 602, and then enters the third stage.

[0101] In the third stage, the connection between the second connector 602 and the battery cavity is disconnected, the end of the second test branch where the second connector 602 is provided is closed, and the main air intake switch valve 102, the fast charging switch valve 301 and the second test switch valve 402 are opened. The second test branch is quickly inflated and the pressure is stabilized before entering the fourth stage.

[0102] In the fourth stage, the connection between the second connector 602 and the battery cavity is kept disconnected, the end of the second test branch provided with the second connector 602 is kept closed, and the second test switch valve 402 is closed, and the second branch exhaust switch valve 702, the first branch detection switch valve 212 and the second branch detection switch valve 213 are opened to discharge gas from the second test branch. After the pressure value displayed by the second branch pressure sensor 502 drops to zero, V is calculated according to the gas flow rate flowing through the flow meter 201 in the fourth stage. 支路 , the V 支路 is the volume of the second test branch.

[0103] In determining V 总 and V 支路 After that, the volume V0 of the battery cavity connected to the second connector 602 can be calculated, that is, V0=V 总 -V 支 road.

[0104] More specifically, assuming that the volume of the battery cavity is V0, the gas in the battery cavity is discharged from the pressure P1 to the atmospheric pressure P0, and the volume of the discharged gas is V1.

[0105] Then at pressure P1, the volume of gas in the cavity under standard conditions is V1+V0;

[0106] The molar mass of the gas in the chamber under standard conditions (pressure P0) is n0 = V0 / 22.4 mol——①;

[0107] The molar mass of the gas in the cavity at the pressure of P1 is n1 = (V1 + V0) / 22.4 mol - ②;

[0108] From the ideal gas state equation: PV = nRT, we can know that P1*V0 = n1*RT, P0*V0 = n0*RT;

[0109] The volume V0 of the cavity remains unchanged, and at the same temperature, the gas constant R remains unchanged;

[0110] Then: P1 / n1=RT / V0=P0 / n0;

[0111] It can be obtained that: P1 / P0=n1 / n0; that is: n1=n0*P1 / P0——③;

[0112] From ②-①, we can get: n1-n0=V1 / 22.4——④;

[0113] Substituting ③ into ④, we get: n0*(P1 / P0-1)=V1 / 22.4——⑤;

[0114] Substitute ① into ⑤ to obtain: V0 / 22.4*(P1 / P0-1)=V1 / 22.4——⑥;

[0115] After sorting, we get: V0 = V1 / (P1 / P0-1)——⑦;

[0116] It should be noted that P0 = 0.1 MPa. As an example, in formula 7, when P1 = 0.15 MPa (in order to reduce the change in cavity volume caused by pressure change, the test pressure P1 is preferably not more than 0.2 MPa), that is, when the pressure in the battery cavity is 50 kPa gauge pressure, the volume of the cavity V0 = V1 / (1.5-1) = 2*V1.

[0117] It should be noted that the above steps can be referred to when measuring the single-chamber volume of the battery chamber connected to the first connector 601 or the battery chamber connected to the third connector 603. Similarly, the above steps can be referred to when measuring the single-chamber volume of a fuel cell having two chambers.

[0118] In some embodiments, reference Fig. 9 The fuel cell air tightness detection device includes a battery full cavity pressure release condition. Under the battery full cavity pressure release condition, each test branch is in a cut-off state and is sequentially connected to the corresponding exhaust branch and the main exhaust pipeline.

[0119] More specifically, after the test items are completed, the pressure of all battery cavities needs to be released. Under the battery full cavity pressure release condition, close the first test switch valve 401, the second test switch valve 402 and the third test switch valve 403, open the first branch exhaust switch valve 701, the second branch exhaust switch valve 702, the third branch exhaust switch valve 703 and the main exhaust switch valve 801, and form Fig. 9The gas path marked with bold lines can complete the pressure release of the entire battery cavity.

[0120] It should be noted that when the full-chamber pressure of a fuel cell with two chambers is released, the above steps may be referred to.

[0121] In some embodiments, reference Fig.10 The fuel cell air tightness detection device includes a pressure relief condition at the front end of the device. Under the pressure relief condition at the front end of the device, the main air intake pipeline, the fast charging pipeline, the second flow detection branch and the main exhaust pipeline are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

[0122] More specifically, after the test items are completed, the front-end pressure of the fuel cell air tightness detection device needs to be released. Under the front-end pressure release condition of the device, close the main air intake switch valve 102, the first test switch valve 401, the second test switch valve 402 and the third test switch valve 403, open the second main detection switch valve 214 and the second branch detection switch valve 213, and form Fig.10 The gas path marked with bold lines can complete the pressure relief at the front end of the device.

[0123] It should be noted that when the pressure at the front end of a fuel cell having two chambers is released, the above steps may be referred to.

[0124] In some embodiments, the fuel cell air tightness detection device may also include a controller, which is electrically connected to the flow meter 201 and all switching valves and pressure sensors in the fuel cell air tightness detection device, and is configured to control the fuel cell air tightness detection device to switch between the various different operating conditions mentioned above.

[0125] However, some existing air tightness testing equipment has added a large number of sensors and switch valves in order to perform more air tightness testing items, which greatly increases the difficulty of the test operation. During the test, the tester is required to be familiar with the battery stack, and the tester with low technical level cannot operate. Therefore, in contrast, the device of this embodiment can automatically control the switch state of each switch valve by setting a controller, so that it can automatically switch to different test conditions, which not only saves manpower, but also reduces the dependence on the technical level of the test operator, and is easier to use.

[0126] In the description of the present application, it should be understood that 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 present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0127] In this 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 connection; it can be a mechanical connection, an electrical connection, or communication with each other; 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 defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0128] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0129] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A fuel cell air tightness detection device, characterized in that: include: An air intake system is provided with a total air intake pipeline and a total pressure sensor (104) connected in series in the total air intake pipeline; A fast-inflating system, comprising a fast-inflating pipeline and a fast-inflating switch valve (301) serially connected in the fast-inflating pipeline; A flow detection system is provided, comprising a flow detection main circuit, a first flow detection branch circuit and a second flow detection branch circuit, wherein a first branch detection switch valve (212) is connected in series to the first flow detection branch circuit, a second branch detection switch valve (213) is connected in series to the second flow detection branch circuit, and the first main circuit detection switch valve (211), a flow meter (201) and a second main circuit detection switch valve (214) are connected in series in sequence along the direction of the inflation airflow in the flow detection main circuit; A branch test system is provided with a plurality of test branches, each of which is serially connected with a test switch valve, a branch pressure sensor and a battery connector in sequence along the direction of the inflation airflow; and An exhaust system is provided with a main exhaust pipeline and a plurality of exhaust branches respectively arranged corresponding to the plurality of test branches, each of the exhaust branches is serially connected with a branch exhaust switch valve, and the main exhaust pipeline is serially connected with a main exhaust switch valve (801); Wherein, along the direction of the inflation air flow, the fast charging pipeline and the flow detection main road are connected in parallel to the downstream end of the total intake pipeline and the upstream ends of the plurality of test branches; one end of the first flow detection branch is connected to the pipe section of the flow detection main road located between the first main road detection switch valve (211) and the flow meter (201), and the other end is connected to the pipe section of the total exhaust pipeline located upstream of the total exhaust switch valve (801); one end of the second flow detection branch is connected to the pipe section of the flow detection main road located between the flow meter (201) and the second main road detection switch valve (214), and the other end is connected to the pipe section of the total exhaust pipeline located downstream of the total exhaust switch valve (801); the downstream end of each exhaust branch is connected to the upstream end of the total exhaust pipeline, and the upstream end of each exhaust branch is connected to the pipe section of the corresponding test branch located between the test switch valve and the branch pressure sensor; all the switch valves in the fuel cell air tightness detection device are independently switched.

2. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a single-chamber pressure-maintaining test condition; In the inflation phase of the single-chamber pressure-maintaining test condition, the main air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; During the test phase of the single-chamber pressure-maintaining test condition, any one of the test branches is switched to a cut-off state.

3. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a full-cavity pressure-maintaining test condition; In the inflation phase of the full-cavity pressure-maintaining test condition, the total air intake pipeline, the fast-charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; During the test phase of the full-cavity pressure-maintaining test condition, all of the test branches are switched to a cut-off state.

4. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a single-chamber external leakage flow test condition; In the inflation phase of the single-chamber external leakage flow test condition, the main air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; During the test phase of the single-chamber external leakage flow test condition, the total air intake pipeline, the flow detection main circuit and any one of the test branches are connected, and the remaining test branches are connected to the total exhaust pipeline through the correspondingly connected exhaust branches.

5. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a full-cavity external leakage flow test condition; In the inflation phase of the full-cavity external leakage flow test condition, the total air intake pipeline, the fast-charging pipeline and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; During the test phase of the full-cavity external leakage flow test condition, the total air intake pipeline, the flow detection main circuit and all the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

6. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a two-chamber crossflow flow test condition. Under the two-chamber crossflow flow test condition, the main air intake pipeline, the fast charging pipeline and any one of the test branches are connected, and one of the remaining test branches is connected in sequence to the corresponding exhaust branch, the section of the main exhaust pipeline located upstream of the main exhaust switch valve (801), the first flow detection branch, the main flow detection branch, the second flow detection branch and the section of the main exhaust pipeline located downstream of the main exhaust switch valve (801).

7. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a single-chamber to two-chamber crossflow test condition. Under the single-chamber to two-chamber crossflow test condition, the main air intake pipeline, the fast charging pipeline and any one of the test branches are connected, and two of the remaining test branches are sequentially connected to the corresponding exhaust branches, the section of the main exhaust pipeline located upstream of the main exhaust switch valve (801), the first flow detection branch, the main flow detection branch, the second flow detection branch and the section of the main exhaust pipeline located downstream of the main exhaust switch valve (801).

8. The fuel cell air tightness detection device according to claim 1, characterized in that: The fuel cell air tightness detection device includes a single chamber volume measurement mode; In the first stage of the single-chamber volume measurement working condition, the total air intake pipeline, the fast-charging pipeline and any one of the test branches are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state; In the second stage of the single-chamber volume measurement working condition, any one of the test branches is switched to a cut-off state, and any one of the test branches is sequentially connected to the corresponding exhaust branch, the pipe section of the total exhaust pipeline located upstream of the total exhaust switch valve (801), the first flow detection branch, the flow detection main road, the second flow detection branch, and the pipe section of the total exhaust pipeline located downstream of the total exhaust switch valve (801); In the third stage of the single-chamber volume measurement working condition, all the battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as those in the first stage; In the fourth stage of the single-chamber volume measurement condition, all the battery connectors are disconnected from the fuel cell, and the on-off states of the remaining pipelines in the fuel cell air tightness detection device are the same as those in the second stage.

9. The fuel cell air tightness detection device according to any one of claims 1 to 8, characterized in that: The fuel cell air tightness detection device includes a battery full-cavity pressure relief working condition. Under the battery full-cavity pressure relief working condition, each of the test branches is in a cut-off state and is sequentially connected to the corresponding exhaust branch and the main exhaust pipeline.

10. The fuel cell air tightness detection device according to claim 9, characterized in that: The fuel cell air tightness detection device includes a pressure relief condition at the front end of the device. Under the pressure relief condition at the front end of the device, the total air intake pipeline, the fast charging pipeline, the second flow detection branch and the total exhaust pipeline are connected, and the remaining pipelines in the fuel cell air tightness detection device are in a cut-off state.

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