Fuel cell stack airtightness detection equipment

Abstract

The utility model relates to the technical field of fuel cell stack airtightness testing, and provides fuel cell stack airtightness detection equipment. The equipment comprises a gas supply module, a flow control module, a pressure detection module, a tail exhaust and a tail exhaust gas detection module which are sequentially connected according to a gas passage, a source end pressure sensor, a first pressure sensor, a second pressure sensor, a three-cavity in-pile pressure sensor, a tail exhaust evacuation branch pressure sensor, a main flow controller, a branch flow controller and a tail exhaust evacuation branch flow meter are arranged in the equipment, and the flow in unit time is obtained by keeping gas supply to reach a preset pressure value. The air tightness test of three cavities and an independent single cavity of the fuel cell stack and the air tightness test of mutual blow-by of the three cavities are realized.

Description

Technical Field

[0001] This utility model relates to the field of fuel cell stack airtightness testing technology, and in particular to a fuel cell stack airtightness testing device. Background Technology

[0002] The airtightness of the fuel cell stack is one of the most strictly controlled aspects in the development and production of fuel cells. Its quality directly affects the safety and performance of the fuel cell. To ensure the assembled fuel cell stack can operate normally for subsequent testing and system integration, it must first undergo an airtightness test to determine if there are any external or internal leaks.

[0003] Existing airtightness testing equipment typically uses flow rate or differential pressure methods, supplemented by third-party voltage testing instruments, to test the overall internal or external leakage of fuel cell stacks. However, it cannot perform individual airtightness leakage rate tests or internal leakage cross-flow rate tests on the three chambers of the fuel cell stack, thus failing to accurately determine the leakage rate standard for external or internal leakage of the fuel cell stack. Utility Model Content

[0004] The technical problem to be solved by this invention is how to efficiently test the leakage rate of the three chambers of a fuel cell stack, both the independent external leakage and the internal leakage between them.

[0005] This utility model solves the above-mentioned technical problems through the following technical solution:

[0006] This utility model provides a fuel cell stack airtightness testing device, which includes the following components connected in sequence according to the gas passage: a gas supply module, a flow control module, a pressure detection module, and an exhaust gas detection module.

[0007] The gas supply module includes several parallel gas supply branches, and the ends of the gas supply branches are connected together and then connected to the flow control module.

[0008] The flow control module includes a main line and branch lines connected in parallel; the input end of the main line is connected to the output end of the gas supply module, and the output end is connected to the pressure detection module.

[0009] The pressure detection module includes a parallel anode cavity branch, a cathode cavity branch, and a coolant cavity branch. The input ends of the three branches are connected together and then connected to the main output end of the flow control module. The output ends of the three branches are connected together and then connected to the tailpipe and tailpipe gas detection module.

[0010] The tail exhaust and tail exhaust gas detection module includes a main circuit and branch circuits connected in parallel, and the input end of the main circuit is connected to the output end of the pressure detection module.

[0011] Furthermore, each branch of the gas supply module includes a solenoid valve and a check valve connected in series.

[0012] Furthermore, the main circuit of the flow control module includes a filter, a source pressure sensor, a pressure reducing valve, a safety valve, a main circuit solenoid valve, a main circuit flow controller, a main circuit check valve, and a first pressure sensor connected in series.

[0013] Furthermore, the flow control module branch includes a branch solenoid valve, a branch flow controller, and a branch check valve connected in series. Its input end is located between the safety valve and the main solenoid valve, and its output end is connected to the main output end.

[0014] Furthermore, the anode cavity branch includes an anode cavity inlet solenoid valve and an anode cavity stack inlet pressure sensor connected in series, and is connected in series via a fuel cell stack anode manifold inlet, a fuel cell anode manifold outlet, and an anode cavity outlet solenoid valve.

[0015] Furthermore, the cathode cavity branch includes a cathode cavity inlet solenoid valve and a cathode cavity stack inlet pressure sensor connected in series, which are connected in series via the fuel cell stack cathode manifold inlet, fuel cell cathode manifold outlet, and cathode cavity outlet solenoid valve.

[0016] Furthermore, the coolant chamber branch includes a coolant chamber inlet solenoid valve and a coolant chamber stack inlet pressure sensor connected in series, and is connected in series with a coolant chamber outlet solenoid valve via the fuel cell stack coolant chamber manifold inlet, fuel cell coolant chamber manifold outlet, and coolant chamber outlet.

[0017] Furthermore, the tailpipe and tailpipe detection module main circuit includes a tailpipe venting main circuit solenoid valve and a safety valve tailpipe pressure relief port connected in series.

[0018] Furthermore, the tailpipe and tailpipe detection module branch includes a tailpipe venting branch solenoid valve, a tailpipe venting branch second pressure sensor, and a tailpipe venting branch flow meter connected in series.

[0019] Preferably, all pipelines are made of 316L stainless steel imperial steel pipes and are connected by compression fittings or clamps.

[0020] Preferably, the range of the main flow controller is greater than that of the branch flow controller, and the accuracy of the branch flow controller is higher than that of the main flow controller.

[0021] Preferably, the range of the source-end pressure sensor is greater than that of the first pressure sensor, the three-chamber inlet pressure sensor, and the second pressure sensor. The source-end pressure sensor and the second pressure sensor are used to measure excessively high protective gas pressure, preventing damage to the flow meter in the fuel cell stack and tailpipe venting branch detection loop of the tested device.

[0022] Preferably, the first pressure sensor is a pressure detection sensor used in the three-chamber pressure holding process, and is also used to prevent the fuel cell stack under test from depressurizing.

[0023] Preferably, the three-cavity infeed pressure sensor is used for pressure detection during three-cavity single-cavity testing and for pressure relief protection to prevent damage to the fuel cell stack under test when the pressure is too high.

[0024] Preferably, the filter in the flow control module is used to filter gas impurities to prevent the tested component from being contaminated or damaged.

[0025] Preferably, the pressure reducing valve in the flow control module is used to reduce the output pressure at the source end, preventing excessive pressure from damaging the downstream main flow controller and branch flow controller. The safety valve is used to protect against pressure relief in case the pressure reducing valve is damaged, further reducing the loss and risk of damage to the downstream main flow controller and branch flow controller.

[0026] The advantages of this utility model are:

[0027] (1) By setting pressure control, flow controller and flow meter to detect the gas flow leakage rate of the test gas in the fuel cell stack under test per unit time, the air tightness and leakage rate test of the three chambers and independent single chamber of the fuel cell stack can be realized efficiently, as well as the air tightness and leakage rate test of the mutual leakage of the three chambers. No complicated instrument assistance and calculation are required, and there are no requirements for the type of fuel cell, so it has good compatibility.

[0028] (2) By setting up multiple parallel gas supply branches and sharing the main pressure sensor, solenoid valve, flow controller and check valve, multiple gas media can be selected for detection according to the requirements of detection accuracy and economic cost. At the same time, the structure of the equipment is optimized and the equipment cost is reduced.

[0029] (3) By setting overpressure protection for source gas pressure, overpressure protection for detection gas, filtration of gas impurities, and pressure reducing valves and safety valves, the risk of property damage to the fuel cell stack and testing equipment under test is reduced. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the system structure of a fuel cell air tightness testing device according to Embodiment 1 of this utility model;

[0031] Figure 2 This is a schematic diagram of the structure of the fuel cell stack under test in Embodiment 1 of this utility model.

[0032] in:

[0033] 100 - Gas supply module: 1010 - Helium inlet, 1011 - Solenoid valve, 1012 - Check valve; 1020 - Nitrogen inlet, 1021 - Solenoid valve, 1022 - Check valve; 1030 - Air, 1031 - Solenoid valve, 1032 - Check valve;

[0034] 200-Flow Control Module: 2001-Filter, 2002-Source Pressure Sensor, 2003-Pressure Reducing Valve, 2004-Safety Valve, 2005-Main Solenoid Valve, 2010-Branch Solenoid Valve, 2006-Main Flow Controller, 2011-Branch Flow Controller, 2007-Main Check Valve, 2012-Branch Check Valve, 2008-First Pressure Sensor;

[0035] 300-Pressure Detection Module: 3001-Anode Chamber Inlet Solenoid Valve, 3002-Anode Chamber Outlet Solenoid Valve, 3003-Anode Chamber Press Pressure Sensor; 3004-Cathode Chamber Inlet Solenoid Valve, 3005-Cathode Chamber Outlet Solenoid Valve, 3006-Cathode Chamber Press Pressure Sensor; 3007-Coolant Chamber Inlet Solenoid Valve, 3008-Coolant Chamber Outlet Solenoid Valve, 3009-Coolant Chamber Press Pressure Sensor;

[0036] 400-Tail exhaust and tail exhaust gas detection module: 4001-Tail exhaust main solenoid valve, wherein the tail exhaust gas detection module also includes 4002-Tail exhaust branch solenoid valve, 4003-Tail exhaust branch pressure sensor, 4004-Tail exhaust branch flow meter, and 4005-Safety valve tail exhaust pressure relief port.

[0037] 500 - Fuel Cell Stack: 5001 - Anode Manifold Inlet, 5002 - Cathode Manifold Inlet, 5003 - Coolant Manifold Inlet, 5004 - Anode Manifold Outlet, 5005 - Cathode Manifold Outlet, 5006 - Coolant Manifold Outlet. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0039] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments:

[0040] Example 1

[0041] like Figure 1 and Figure 2 As shown, this embodiment provides a fuel cell stack airtightness testing device for detecting the airtightness of a fuel cell stack, comprising: a gas supply module 100, a flow control module 200, a pressure detection module 300, an exhaust gas detection module 400, and a fuel cell stack 500. The gas supply module 100, the flow control module 200, the pressure detection module 300, the fuel cell stack 500, and the exhaust gas detection module 400 are connected in sequence.

[0042] The gas supply module has three parallel branches, including: a helium inlet 1010, equipped with a solenoid valve 1011 and a check valve 1012 connected in series; a nitrogen inlet 1020, equipped with a solenoid valve 1021 and a check valve 1022 connected in series; and an air inlet, equipped with a solenoid valve 1031 and a check valve 1032 connected in series. Finally, the three gas supply branches are connected to the inlet of the flow control module 200.

[0043] The main circuit of the flow control module 200 includes a filter 2001, a source pressure sensor 2002, a pressure reducing valve 2003, a safety valve 2004, a main circuit solenoid valve 2005, a main circuit flow controller 2006, a main circuit check valve 2007, and a first pressure sensor 2008 connected in series. The branch circuits of the flow control module 200 include a branch circuit solenoid valve 2010, a flow controller 2011, and a check valve 2012 connected in series. The inlet of the branch circuit solenoid valve 2010 is connected in parallel to the front end of the main circuit solenoid valve 2005, and the outlet of the branch circuit check valve 2012 is connected in parallel to the rear end of the main circuit check valve 2007. The function of all check valves is to prevent backflow of gas in case of unexpected situations, such as when the outlet pressure at the rear end of the solenoid valve is higher than the inlet pressure at the front end. This prevents hydrogen or oxygen-containing gases inside the fuel cell from mixing at the gas medium source, thus avoiding potential risks.

[0044] The pressure detection module 300 has three parallel branches, namely:

[0045] The anode cavity branch includes an anode cavity inlet solenoid valve 3001 and an anode cavity stack inlet pressure sensor 3003 connected in series. It is connected in series with the fuel cell stack anode manifold inlet 5001, the fuel cell anode manifold outlet 5004 and the anode cavity outlet solenoid valve 3002, and then connected in parallel to the tailpipe and tailpipe gas detection module 400 pipeline.

[0046] The cathode cavity branch includes a cathode cavity inlet solenoid valve 3004 and a cathode cavity stack inlet pressure sensor 3006 connected in series. It is connected in series with the cathode manifold inlet 5002 and the cathode manifold outlet 5005 of the fuel cell stack, and then connected in parallel to the tailpipe and tailpipe gas detection module 400 pipeline.

[0047] The coolant chamber branch includes a coolant chamber inlet solenoid valve 3007 and a coolant chamber stack inlet pressure sensor 3009 connected in series. It is connected in series with the coolant chamber manifold inlet 5003, the coolant chamber manifold outlet 5006 and the coolant chamber outlet solenoid valve 3008, and then connected in parallel to the tailpipe and tailpipe gas detection module 400 pipeline.

[0048] The main circuit of the tailpipe and tailpipe gas detection module 400 is equipped with a tailpipe venting main circuit solenoid valve 4001, a tailpipe venting pipe, and a safety valve tailpipe pressure relief port 4005 connected in series. The branch circuit of the tailpipe and tailpipe gas detection module is equipped with a tailpipe venting branch solenoid valve 4002, a tailpipe venting branch pressure sensor 4003, and a tailpipe venting branch flow meter 4004 connected in series, and then connected in parallel to converge into the tailpipe venting pipe.

[0049] The main flow controller 2006 has a larger range than the branch flow controller 2011, and both of them have flow accumulation functions.

[0050] The source-end pressure sensor 2002 has a measurement protection function, and its detection range is higher than the source-end gas pressure range. The first pressure sensor 2008 is used for three-chamber protection and measurement functions, and its detection range is higher than the pressure reduction range of the pressure reducing valve 2003. The anode chamber inlet pressure sensor 3003, the cathode chamber inlet pressure sensor 3006, and the coolant chamber inlet pressure sensor 3009 are greater than or equal to the highest pressure range detected by the fuel cell stack airtightness testing equipment or the stack test pressure.

[0051] In this embodiment, all main and branch pipelines are made of 316L stainless steel imperial steel pipes and are connected by ferrules or clamps; the fuel cell stack three-chamber manifold connection is a quick-connect clamp.

[0052] The process of airtightness testing using this fuel cell stack airtightness testing equipment is as follows:

[0053] (1) The process of testing the gas leakage rate of each of the three chambers of the fuel cell stack and the total gas leakage rate of the three chambers is as follows:

[0054] The gas supply module and flow control module provide test gas to the pressure detection module, fuel cell stack and exhaust gas detection module.

[0055] By adjusting the flow output range of the main flow controller, the test chamber of the fuel cell stack is brought to a preset pressure. All control solenoid valves on the branches other than the test chamber are closed. The pressure of the test chamber is maintained at the preset pressure by the continuous and stable output flow of the branch flow controller within a predetermined time. The cumulative flow output of the branch flow controller is monitored to realize the external leakage detection function of each chamber of the fuel cell stack. The leakage rate of each chamber of the fuel cell stack per unit time is obtained by the cumulative flow difference.

[0056] Therefore, the external leakage detection modes for each cavity of the fuel cell stack include:

[0057] The anode cavity external leakage detection mode of the fuel cell stack is used to detect whether gas is leaking from the anode cavity of the fuel cell stack and the leakage rate.

[0058] The external leakage detection mode of the coolant chamber of the fuel cell stack is used to detect whether gas is leaking from the coolant chamber of the fuel cell stack and the leakage rate.

[0059] The external leakage detection mode of the cathode cavity of the fuel cell stack is used to detect whether gas is leaking from the cathode cavity of the fuel cell stack and the leakage rate.

[0060] The external leakage detection modes of the anode cavity, coolant cavity and cathode cavity of the fuel cell stack are used to detect the total external leakage amount and leakage rate of the three cavities of the fuel cell stack.

[0061] (2) The process of testing the gas leakage rate of each cavity of the fuel cell stack is as follows:

[0062] Open the inlet solenoid valve of the chamber to be tested, and close the inlet and outlet solenoid valves of the other chamber pipelines and the vent solenoid valve of the fuel cell manifold outlet.

[0063] The gas supply solenoid valve is opened, and the pressure inside the test chamber circuit and fuel cell stack is brought to a preset pressure via the main flow controller. The inlet solenoid valve of the test chamber is then closed. The outlet solenoid valve of the chamber connected to the test chamber and the tail exhaust vent branch solenoid valve are opened. The flow rate of the tail exhaust vent branch flow meter is continuously monitored and accumulated within a predetermined time. This allows the determination of the leakage amount and leakage rate between the test chamber and the connected chambers within a preset time period measured by the tail exhaust gas detection module.

[0064] The leakage test of fuel cell stacks in different modes mainly depends on the ventilation control of the solenoid valve of the test chamber. The opening and closing status of the solenoid valve of different chambers determines the leakage test mode of a certain chamber of the fuel cell stack.

[0065] Therefore, the cross-leakage test modes between the cavities of a fuel cell stack include:

[0066] The anode-cathode leakage detection mode is used to detect whether gas is leaking from the anode cavity to the cathode cavity of the fuel cell stack.

[0067] The anode-cathode cavity and coolant cavity leakage detection mode is used to detect whether gas is leaking from the anode cavity of the fuel cell stack to the cathode cavity and coolant cavity.

[0068] The coolant chamber-anode leakage detection mode is used to detect whether gas is leaking from the coolant chamber of the fuel cell stack to the anode chamber.

[0069] The coolant chamber-cathode chamber leakage detection mode is used to detect whether gas is leaking from the coolant chamber of the fuel cell stack to the cathode chamber.

[0070] After the test is completed, first close the tail exhaust vent branch solenoid valve and the gas supply control valve, open the inlet solenoid valve of the tested cavity and the corresponding outlet solenoid valve of the tested cavity, and open the tail exhaust vent main solenoid valve to safely depressurize the fuel cell air tightness testing equipment.

[0071] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A fuel cell stack airtightness testing device, characterized in that, It includes the following components connected in sequence according to the gas path: gas supply module, flow control module, pressure detection module, tailpipe and tailpipe gas detection module; The gas supply module includes several parallel gas supply branches, and the ends of the gas supply branches are connected together and then connected to the flow control module. The flow control module includes a main line and branch lines connected in parallel; the input end of the main line is connected to the output end of the gas supply module, and the output end is connected to the pressure detection module. The pressure detection module includes a parallel anode cavity branch, a cathode cavity branch, and a coolant cavity branch. The input ends of the three branches are connected together and then connected to the main output end of the flow control module. The output ends of the three branches are connected together and then connected to the tailpipe and tailpipe gas detection module. The tail exhaust and tail exhaust gas detection module includes a main circuit and branch circuits connected in parallel, and the input end of the main circuit is connected to the output end of the pressure detection module.

2. The fuel cell stack airtightness testing device according to claim 1, characterized in that, Each branch of the gas supply module includes a solenoid valve and a check valve connected in series.

3. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The main flow control module includes a filter, a source pressure sensor, a pressure reducing valve, a safety valve, a main flow solenoid valve, a main flow controller, a main flow check valve, and a first pressure sensor, which are connected in series.

4. The fuel cell stack airtightness testing device according to claim 3, characterized in that, The flow control module branch includes a branch solenoid valve, a branch flow controller, and a branch check valve connected in series. Its input end is located between the safety valve and the main solenoid valve, and its output end is located between the main check valve and the first pressure sensor.

5. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The anode cavity branch includes an anode cavity inlet solenoid valve and an anode cavity stack inlet pressure sensor connected in series, and is connected in series with the fuel cell stack anode manifold inlet, fuel cell anode manifold outlet, and anode cavity outlet solenoid valve.

6. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The cathode cavity branch includes a cathode cavity inlet solenoid valve and a cathode cavity stack inlet pressure sensor connected in series, and is connected in series via a solenoid valve at the inlet of the fuel cell stack cathode manifold, the outlet of the fuel cell cathode manifold, and the outlet of the cathode cavity.

7. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The coolant chamber branch includes a coolant chamber inlet solenoid valve and a coolant chamber stack inlet pressure sensor connected in series, and is connected in series with a coolant chamber outlet solenoid valve via the fuel cell stack coolant chamber manifold inlet, fuel cell coolant chamber manifold outlet, and coolant chamber outlet.

8. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The tailpipe and tailpipe detection module main circuit includes a tailpipe venting main circuit solenoid valve and a safety valve tailpipe pressure relief port connected in series.

9. The fuel cell stack airtightness testing device according to claim 1, characterized in that, The tailpipe and tailpipe detection module branch includes a tailpipe venting branch solenoid valve, a tailpipe venting branch second pressure sensor, and a tailpipe venting branch flow meter connected in series.

10. A fuel cell stack airtightness testing device according to any one of claims 1-9, characterized in that, All piping is made of 316L stainless steel imperial steel pipe and is connected by compression fittings or clamps.

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