Gas supply system of fuel cell

Abstract

The embodiment of the invention discloses a gas supply system of a fuel cell. The gas supply system comprises an oxygen supply module, a nitrogen supply module and a gas mixing module, the oxygen supply module comprises an oxygen source which is used for providing oxygen; the nitrogen supply module comprises a nitrogen source which is used for providing nitrogen; the gas mixing module is respectively communicated with the oxygen supply module and the nitrogen supply module, and gas is mixed in the gas mixing module to obtain mixed gas; and the gas mixing module is also communicated with the cathode of the fuel cell and is used for supplying mixed gas to the fuel cell. After the gas supply system is applied to the fuel cell, the output power and efficiency of the fuel cell can be improved, and the stability and durability of the fuel cell can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of fuel cells, and in particular to a gas supply system for a fuel cell. Background Art

[0002] With the rapid development of hydrogen energy, the application of proton exchange membrane fuel cell systems is becoming more and more extensive. The proton exchange membrane fuel cell system is mainly composed of a fuel cell stack, an oxidizing gas supply subsystem, a reducing gas supply subsystem, a thermal management subsystem, a control subsystem, etc. For the proton exchange membrane fuel cell system, how to improve its output power and efficiency, and improve its stability and durability is the focus of current research. Summary of the invention

[0003] In view of this, an embodiment of the present application hopes to provide a gas supply system for a fuel cell, which is intended to help improve the output power and efficiency of the fuel cell, and also to help improve the stability and durability of the fuel cell.

[0004] To solve the above problems, the technical solution of the embodiment of the present application is implemented as follows:

[0005] The present application provides a fuel cell gas supply system, including:

[0006] An oxygen supply module, comprising an oxygen source, wherein the oxygen source is used to provide oxygen;

[0007] A nitrogen supply module, comprising a nitrogen source, wherein the nitrogen source is used to provide nitrogen;

[0008] A gas mixing module is connected to the oxygen supply module and the nitrogen supply module respectively, and the gases are mixed in the gas mixing module to obtain a mixed gas; the gas mixing module is also connected to the cathode of the fuel cell to supply the mixed gas to the fuel cell.

[0009] In some embodiments, the oxygen supply module further comprises a first decompression unit, which is disposed downstream of the oxygen source and is used to control the supply pressure of the oxygen source; and / or,

[0010] The oxygen supply module further includes a first flow control unit, which is disposed downstream of the oxygen source and is used to control the supply flow of the oxygen source.

[0011] In some embodiments, the nitrogen supply module further includes a second decompression unit, which is disposed downstream of the nitrogen source and is used to control the supply pressure of the nitrogen source; and / or,

[0012] The nitrogen supply module further includes a second flow control unit, which is disposed downstream of the nitrogen source and is used to control the supply flow of the nitrogen source.

[0013] In some embodiments, the gas supply system further includes an air supply module, which is in communication with the gas mixing module and is configured to provide air to the gas mixing module, wherein the mixed gas includes the air.

[0014] In some embodiments, the air supply module includes an air compressor and a third flow control unit, the inlet of the air compressor is connected to the atmosphere, and the outlet is connected to the gas mixing module through the third flow control unit, and the third flow control unit is used to control the supply flow of the air.

[0015] In some embodiments, the gas mixing module includes a gas mixing unit and a gas storage unit that are interconnected, the gas mixing unit is respectively connected to the oxygen supply module, the nitrogen supply module and the air supply module, and can mix the oxygen, the nitrogen and the air to obtain the mixed gas; the gas storage unit is used to store the mixed gas and can supply the mixed gas to the fuel cell.

[0016] In some embodiments, the gas mixing module further comprises a circulation pipeline and a driving member, wherein both ends of the circulation pipeline are respectively connected to two different positions of the gas storage unit, and the driving member is disposed on the circulation pipeline and can drive the mixed gas to flow from one end of the circulation pipeline to the other end; and / or,

[0017] The gas circulation module further includes an oxygen concentration monitoring component, which is used to monitor the oxygen concentration of the mixed gas in the gas storage unit.

[0018] In some embodiments, the gas circulation module further includes a pressure relief pipeline and a pressure relief valve, one end of the pressure relief pipeline is connected to the gas storage unit, and the other end is connected to the outside of the gas storage unit, and the pressure relief valve is arranged on the pressure relief pipeline.

[0019] In some embodiments, the gas circulation module further comprises a pressure monitoring component, wherein the pressure monitoring component is used to monitor the pressure of the mixed gas in the gas storage unit; and / or,

[0020] The air supply module comprises an air compressor, an inlet of the air compressor is communicated with the atmosphere, an outlet of the air compressor is communicated with the gas mixing unit, and the other end of the pressure relief pipeline is communicated with the inlet of the air compressor.

[0021] In some embodiments, the oxygen provided by the oxygen source is high purity oxygen; and / or,

[0022] The nitrogen provided by the nitrogen source is high-purity nitrogen; and / or,

[0023] The fuel cell is a proton exchange membrane fuel cell.

[0024] The gas supply system of the fuel cell of the embodiment of the present application mixes oxygen and nitrogen to form a mixed gas and supplies it to the cathode of the fuel cell. Oxygen, as an oxidizing gas, is a necessary reactant for the fuel cell. The oxygen concentration in the mixed gas can be adjusted. By appropriately increasing the oxygen concentration in the mixed gas, the output power and efficiency of the fuel cell can be increased, that is, a fuel cell stack and system with a high oxygen concentration can be developed in a targeted manner; and nitrogen, as an inert gas, can improve the transmission of oxygen and reduce the concentration polarization inside the fuel cell, thereby improving the efficiency of the battery. In addition, the addition of nitrogen helps to regulate the temperature of the fuel cell, because nitrogen does not participate in the chemical reaction in the reaction, but can take away some heat, thereby avoiding overheating of the fuel cell. The gas mixing module can evenly mix oxygen and nitrogen, so that the oxygen concentration in the mixed gas can be in a relatively stable state. When the fuel cell is reacting, the oxidizing gas can be continuously and stably supplied, thereby helping to improve the stability and efficiency of the fuel cell reaction. In summary, after the gas supply system of the embodiment of the present application is applied to the fuel cell, it is beneficial to improve the output power and efficiency of the fuel cell, and it is also beneficial to improve the stability and durability of the fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a gas supply system for a fuel cell according to an embodiment of the present application.

[0026] Description of Reference Numerals

[0027] 10. Oxygen supply module; 11. Oxygen source; 12. First pressure reducing unit; 13. First flow control unit; 20. Nitrogen supply module; 21. Nitrogen source; 22. Second pressure reducing unit; 23. Second flow control unit; 30. Gas mixing module; 31. Gas mixing unit; 32. Gas storage unit; 33. Circulation pipeline; 34. Driving element; 35. Oxygen concentration monitoring element; 36. Pressure relief pipeline; 37. Pressure relief valve; 38. Pressure monitoring element; 40. Air supply module; 41. Air compressor; 42. Third flow control unit. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. The following embodiments are only used to more clearly illustrate the technical scheme of the present application, and are therefore only used as examples, and the protection scope of the present application cannot be limited by this. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0029] In the description of the embodiments of the present application, the technical terms "first", "second", "third", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0030] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0031] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0032] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "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 or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0033] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and may be direct contact or contact through an intermediate medium layer. It may be contact with essentially no interaction force between the two contacting parties, or it may be contact with interaction force between the two contacting parties.

[0034] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] With the rapid development of hydrogen energy, the application of proton exchange membrane fuel cell system is becoming more and more extensive. Proton exchange membrane hydrogen fuel cell system is mainly composed of fuel cell stack, oxidation gas supply subsystem, reduction gas supply subsystem, thermal management subsystem, control subsystem, etc.

[0036] The fuel cell stack is the core device of energy conversion, which mainly includes membrane electrode, bipolar plate, end plate, etc., and is responsible for converting chemical energy into electrical energy; the reducing gas supply subsystem mainly includes proportional valve, circulation pump, safety valve, etc., and its main function is to provide the reducing gas (hydrogen) required for power generation to the fuel cell stack; the oxidizing gas supply subsystem mainly includes filter, air compressor, throttle, etc., and its main function is to provide the oxidizing gas required for power generation of the fuel cell stack; the thermal management subsystem mainly includes water pump, heat dissipation module, PTC heater, etc., and its main function is to ensure that the fuel cell stack works at normal temperature; the control subsystem mainly includes fuel cell controller (FCU), cell voltage monitoring controller (CVM), sensor, DC / DC, AC / DC, display screen, etc., and uses the designed control strategy through the signal detected by the sensor to ensure the normal operation of the power generation system.

[0037] In the proton exchange membrane fuel cell system, the oxidant supply subsystem is one of the key components, which provides the battery system with the necessary oxygen for electrochemical reactions. In the related art, the oxidant supply subsystem directly uses air as the oxidant source. The content of various gases in the air is relatively fixed, which makes it impossible for the battery system to operate under better working conditions, resulting in the inability to improve the output power and efficiency of the battery system, and the stability and durability cannot be improved.

[0038] In view of this, an embodiment of the present application provides a gas supply system for a fuel cell.

[0039] It should be noted that the gas supply system of the embodiment of the present application is used to supply oxidizing gas to the cathode of the fuel cell, that is, the supply system is an oxidizing gas supply subsystem.

[0040] The specific type of the fuel cell is not limited. For example, the fuel cell may be a proton exchange membrane fuel cell.

[0041] See also Figure 1 The gas supply system includes an oxygen supply module 10 , a nitrogen supply module 20 and a gas mixing module 30 .

[0042] The oxygen supply module 10 includes an oxygen source 11 for providing oxygen.

[0043] It should be noted that the specific type of the oxygen source 11 is not limited. In some embodiments, the oxygen provided by the oxygen source 11 is high-purity oxygen, and the source of high-purity oxygen is relatively wide and easy to obtain. In other embodiments, the oxygen provided by the oxygen source 11 can also be ordinary oxygen, but its impurity content needs to be controlled to meet the intake quality requirements of the fuel cell.

[0044] The nitrogen supply module 20 includes a nitrogen source 21 for providing nitrogen.

[0045] It should be noted that the specific type of the nitrogen source 21 is not limited. In some embodiments, the nitrogen provided by the nitrogen source 21 is high-purity nitrogen, and the source of high-purity nitrogen is relatively wide and easy to obtain. In other embodiments, the nitrogen provided by the nitrogen source 21 can also be ordinary nitrogen, but its impurity content needs to be controlled to meet the intake quality requirements of the fuel cell.

[0046] The gas mixing module 30 is connected to the oxygen supply module 10 and the nitrogen supply module 20 respectively. The gases are mixed in the gas mixing module 30 to obtain a mixed gas. The gas mixing module 30 is also connected to the cathode of the fuel cell to supply the mixed gas to the fuel cell.

[0047] It should be noted that after the oxygen source 11 provides oxygen to the gas mixing module 30 and the nitrogen source 21 provides nitrogen to the gas mixing module 30, it is explained that the mixed gas includes oxygen and nitrogen.

[0048] It is understandable that at the cathode of the fuel cell, oxygen is mainly used as an oxidizing gas to participate in the reaction, while nitrogen, as an inert gas, can improve the transmission of oxygen and reduce the concentration polarization inside the fuel cell, thereby improving the efficiency of the battery. In addition, the addition of nitrogen helps to regulate the temperature of the fuel cell, because nitrogen does not participate in the chemical reaction in the reaction, but can take away some heat, thereby preventing the fuel cell from overheating.

[0049] Oxygen and nitrogen are mixed by the gas mixing module 30, and the oxygen and nitrogen can be evenly mixed, so that the oxygen concentration in the mixed gas can be in a relatively stable state. When the fuel cell is reacting, the oxidizing gas can be continuously and stably supplied, which is conducive to improving the stability and efficiency of the fuel cell reaction.

[0050] The oxygen concentration in the mixed gas can be adjusted by adjusting the oxygen supply flow rate of the oxygen source 11; and / or by adjusting the nitrogen supply flow rate of the nitrogen source 21. In this way, the oxygen concentration in the mixed gas can be adjusted according to actual needs. Properly increasing the oxygen concentration can increase the output power and efficiency of the fuel cell, and a fuel cell stack and system with a high oxygen concentration can be developed in a targeted manner.

[0051] The gas supply system of the fuel cell of the embodiment of the present application mixes oxygen and nitrogen to form a mixed gas and supplies it to the cathode of the fuel cell. Oxygen, as an oxidizing gas, is a necessary reactant for the fuel cell. The oxygen concentration in the mixed gas can be adjusted. By appropriately increasing the oxygen concentration in the mixed gas, the output power and efficiency of the fuel cell can be increased, that is, a fuel cell stack and system with a high oxygen concentration can be developed in a targeted manner; and nitrogen, as an inert gas, can improve the transmission of oxygen and reduce the concentration polarization inside the fuel cell, thereby improving the efficiency of the battery. In addition, the addition of nitrogen helps to regulate the temperature of the fuel cell, because nitrogen does not participate in the chemical reaction in the reaction, but can take away some heat, thereby avoiding overheating of the fuel cell. The gas mixing module 30 can evenly mix oxygen and nitrogen, so that the oxygen concentration in the mixed gas can be in a relatively stable state. When the fuel cell is reacting, the oxidizing gas can be continuously and stably supplied, thereby helping to improve the stability and efficiency of the fuel cell reaction. In summary, after the gas supply system of the embodiment of the present application is applied to the fuel cell, it is beneficial to improve the output power and efficiency of the fuel cell, and it is also beneficial to improve the stability and durability of the fuel cell.

[0052] For some examples, see Figure 1 The oxygen supply module 10 further includes a first decompression unit 12 , which is disposed downstream of the oxygen source 11 and is used to control the supply pressure of the oxygen source 11 .

[0053] There is no limitation on the way in which the first decompression unit 12 regulates the supply pressure of the oxygen source 11. For example, the first decompression unit 12 can be automatically adjusted according to the pressure requirement of the mixed gas.

[0054] In this embodiment, the supply pressure of the oxygen source 11 is controlled by the first decompression unit 12, which is beneficial to regulating the pressure of the mixed gas within a suitable range and improving the safety and stability of the gas supply system.

[0055] For some examples, see Figure 1 The oxygen supply module 10 further includes a first flow control unit 13 , which is disposed downstream of the oxygen source 11 and is used to control the supply flow of the oxygen source 11 .

[0056] The specific type of the first flow control unit 13 is not limited. For example, the first flow control unit 13 can be a throttle valve, a speed regulating valve, etc.

[0057] Exemplarily, the first flow control unit 13 can be automatically adjusted according to the demand for oxygen by the gas supply system.

[0058] In this embodiment, the oxygen supply module 10 can provide oxygen with a suitable flow rate according to the amount of oxygen required by the rear end, so as to accurately control the mixing ratio of oxygen and nitrogen to meet the performance requirements under different operating conditions. In addition, it can ensure that a stable gas flow rate is provided under different load conditions to maintain the consistency of fuel cell performance.

[0059] For some examples, see Figure 1 The nitrogen supply module 20 further includes a second decompression unit 22 , which is disposed downstream of the nitrogen source 21 and is used to control the supply pressure of the nitrogen source 21 .

[0060] There is no limitation on the manner in which the second decompression unit 22 regulates the supply pressure of the nitrogen source 21. For example, the second decompression unit 22 can be automatically adjusted according to the pressure requirement of the mixed gas.

[0061] In this embodiment, the supply pressure of the nitrogen source 21 is controlled by the second decompression unit 22, which is beneficial for regulating the pressure of the mixed gas within a suitable range and for improving the safety and stability of the gas supply system.

[0062] For some examples, see Figure 1 The nitrogen supply module 20 further includes a second flow control unit 23 . The second flow control unit 23 is disposed downstream of the nitrogen source 21 and is used to control the supply flow of the nitrogen source 21 .

[0063] The specific type of the second flow control unit 23 is not limited. For example, the second flow control unit 23 can be a throttle valve, a speed regulating valve, etc.

[0064] Exemplarily, the second flow control unit 23 can be automatically adjusted according to the demand for nitrogen by the gas supply system.

[0065] In this embodiment, the nitrogen supply module 20 can provide nitrogen with a suitable flow rate according to the amount of nitrogen required by the rear end, so as to accurately control the mixing ratio of oxygen and nitrogen to meet the performance requirements under different operating conditions. In addition, it can ensure that a stable gas flow rate is provided under different load conditions to maintain the consistency of fuel cell performance.

[0066] For some examples, see Figure 1 The gas supply system further includes an air supply module 40, which is communicated with the gas mixing module 30 and is used to provide air to the gas mixing module 30, wherein the mixed gas includes air.

[0067] In this embodiment, the mixed gas may be a mixture of oxygen, nitrogen and air, and of course, the mixed gas may also include only air. In this way, the gas supply system can be adapted to various usage requirements of the fuel cell.

[0068] When the mixed gas includes only air, the first flow control unit 13 can close the oxygen supply path of the oxygen source 11 , and the second flow control unit 23 can close the nitrogen supply path of the nitrogen source 21 , and only supply gas to the gas mixing module 30 through the air supply module 40 .

[0069] Air can be used as a regulating gas for the mixed gas, which can effectively adjust the composition of the mixed gas, thereby making it easier to control the oxygen concentration and nitrogen concentration in the mixed gas within an appropriate range.

[0070] In some embodiments, during the operation of the fuel cell, only the air supply module 40 may be used to supply air to the gas mixing module 30, and both the oxygen supply module 10 and the nitrogen supply module 20 may not provide gas. In this way, the fuel cell can only use oxygen in the air as the oxidizing gas to meet the operation of the fuel cell under normal working conditions.

[0071] It should be noted that the oxygen supply module 10, the nitrogen supply module 20 and the air supply module 40 provide oxygen, nitrogen and air respectively, and the three gases are mixed in the gas mixing module 30. Before the three gases enter the gas mixing module 30, a one-way valve needs to be set on the inlet pipeline of each gas.

[0072] For some examples, see Figure 1 The air supply module 40 includes an air compressor 41 and a third flow control unit 42. The inlet of the air compressor 41 is connected to the atmosphere, and the outlet is connected to the gas mixing module 30 through the third flow control unit 42. The third flow control unit 42 is used to control the supply flow of air.

[0073] The specific type of the air compressor 41 can be matched according to the actual flow demand.

[0074] The specific type of the third flow control unit 42 is not limited. For example, the third flow control unit 42 can be a throttle valve, a speed regulating valve, etc.

[0075] Exemplarily, the third flow control unit 42 can be automatically adjusted according to the air demand of the air supply system.

[0076] The third flow control unit 42 can control the supply flow of air, and in some embodiments, the third flow control unit 42 can also display the current air flow.

[0077] In this embodiment, the air supply module 40 can supply air based on the actual air demand at the rear end, which is beneficial to the precise control and regulation of the air supply.

[0078] In some embodiments, the gas mixing module 30 includes a gas mixing unit 31 and a gas storage unit 32 which are interconnected. The gas mixing unit 31 is respectively connected to the oxygen supply module 10, the nitrogen supply module 20 and the air supply module 40, and can mix oxygen, nitrogen and air to obtain a mixed gas; the gas storage unit 32 is used to store the mixed gas and can supply the mixed gas to the fuel cell.

[0079] There is no limitation on the specific type of the gas mixing unit 31. For example, the gas mixing unit 31 may be a pipeline mixer, which performs preliminary mixing of oxygen, nitrogen and air. The form and size of the pipeline mixer may be set according to the actual flow rate of the mixed gas.

[0080] The pipeline mixer can be a static mixer or a dynamic mixer, and common forms include static baffle type, orifice plate type, three-way mixer, etc.

[0081] The specific type of the gas storage unit 32 is not limited. For example, the gas storage unit 32 can be a gas storage tank. More specifically, it can be a stainless steel storage tank.

[0082] The gas storage unit 32 is located downstream of the gas mixing unit 31. The mixed gas can be statically mixed inside the gas storage unit 32, so that the mixture of oxygen and nitrogen, or oxygen, nitrogen and air is more uniform, thereby facilitating the precise control of the oxygen concentration in the mixed gas.

[0083] It can be understood that the mixed gas is then supplied to the fuel cell via the gas storage unit 32 , so that the oxygen supply to the fuel cell is more stable, which is beneficial to improving the performance of the fuel cell.

[0084] For some examples, see Figure 1 The gas mixing module 30 also includes a circulation pipeline 33 and a driving member 34. The two ends of the circulation pipeline 33 are respectively connected to two different positions of the gas storage unit 32. The driving member 34 is arranged on the circulation pipeline 33 and can drive the mixed gas to flow from one end of the circulation pipeline 33 to the other end.

[0085] Specifically, one end of the circulation pipeline 33 is connected to the top of the gas storage unit 32, and the other end is connected to the bottom of the gas storage unit 32. In this way, most of the mixed gas in the gas storage unit 32 can be migrated through the circulation pipeline 33, thereby maximizing the uniformity of the mixed gas.

[0086] The specific type of the driving member 34 is not limited. For example, the driving member 34 may be a gas circulation pump.

[0087] The driving member 34 is helpful to improve the uniformity of the mixed gas in the gas storage unit 32. Specifically, the driving member 34 can realize uniform mixing of the mixed gas by forced circulation, thereby further improving the stability of the oxygen supply to the cathode of the fuel cell.

[0088] For some examples, see Figure 1 The gas circulation module further includes an oxygen concentration monitoring component 35 , which is used to monitor the oxygen concentration of the mixed gas in the gas storage unit 32 .

[0089] The installation position of the oxygen concentration monitoring element 35 is not limited.

[0090] In some embodiments, the oxygen concentration monitoring component 35 is disposed on the communication path between the gas storage unit 32 and the cathode inlet of the fuel cell, so that the oxygen concentration monitoring component 35 can more accurately obtain the oxygen concentration in the mixed gas supplied by the gas supply system to the fuel cell.

[0091] In other embodiments, the oxygen concentration monitoring component 35 is disposed on the gas storage unit 32 , so as to monitor the oxygen concentration in the mixed gas in the gas storage unit 32 .

[0092] The oxygen concentration monitoring component 35 can be interlocked with the driving component 34 for control. The uniformity of the mixed gas in the gas storage unit 32 can be evaluated by the oxygen concentration monitoring component 35. When the oxygen concentration remains stable for a certain period of time, it means that the uniformity of the mixed gas is good and the driving component 34 does not need to be turned on. When the oxygen concentration is unstable, it means that the uniformity of the mixed gas needs to be improved. At this time, the driving component 34 is controlled to be turned on to circulate the mixed gas in the gas storage unit 32.

[0093] In addition, the oxygen concentration monitoring component 35 can also be used to feedback and adjust the flow rates of oxygen, nitrogen and air, thereby achieving automatic adjustment of the first flow control unit 13 , the second flow control unit 23 and the third flow control unit 42 .

[0094] There is no limitation on the specific number of oxygen concentration monitoring components 35. For example, the number of oxygen concentration monitoring components 35 is not less than two, which is helpful to avoid the fuel cell being affected by the measurement deviation of a single oxygen concentration monitoring component 35.

[0095] For some examples, see Figure 1 The gas circulation module also includes a pressure relief pipeline 36 and a pressure relief valve 37 . One end of the pressure relief pipeline 36 is connected to the gas storage unit 32 , and the other end is connected to the outside of the gas storage unit 32 . The pressure relief valve 37 is arranged on the pressure relief pipeline 36 .

[0096] The specific type of the pressure relief valve 37 is not limited.

[0097] In some embodiments, the pressure relief valve 37 may be a solenoid valve, which is opened or closed by an electrical signal. Thus, the control method of the pressure relief valve 37 is more convenient.

[0098] In other embodiments, the pressure relief valve 37 can be a safety valve. When the pressure inside the gas storage unit 32 reaches a set value, the mixed gas can automatically open the valve flap of the safety valve to achieve pressure relief; when the pressure inside the gas storage unit 32 is lower than the set value, the valve flap of the safety valve can automatically close.

[0099] In this embodiment, it is convenient to control the pressure of the mixed gas inside the gas storage unit 32 so that the pressure of the mixed gas can meet the intake pressure requirement of the fuel cell, thereby avoiding the influence of excessive pressure on the fuel cell.

[0100] For some examples, see Figure 1 The gas circulation module further includes a pressure monitoring component 38 , which is used to monitor the pressure of the mixed gas in the gas storage unit 32 .

[0101] The setting position of the pressure monitoring component 38 is not limited. Exemplarily, the pressure monitoring component 38 is also arranged on the pressure relief pipeline 36.

[0102] By providing the pressure monitoring component 38 , the pressure inside the gas storage unit 32 can be monitored in real time, thereby facilitating the control of the pressure relief valve 37 .

[0103] In addition, the pressure monitoring component 38 can also provide feedback signals, and the flow rates of oxygen, nitrogen and air can be controlled by using the feedback signals.

[0104] The communication position of the outlet of the pressure relief pipe 36 is not limited.

[0105] In some embodiments, the outlet of the pressure relief pipe 36 is connected to the atmosphere, so that the excess mixed gas inside the gas storage unit 32 is directly discharged into the atmosphere.

[0106] In some other embodiments, please refer to Figure 1 The air supply module 40 further includes an air compressor 41 , an inlet of the air compressor 41 is connected to the atmosphere, an outlet of the air compressor 41 is connected to the gas mixing unit 31 , and the other end of the pressure relief line 36 is connected to the inlet of the air compressor 41 .

[0107] In this way, the excess mixed gas in the gas storage unit 32 can be returned to the gas supply system again, thereby achieving maximum utilization of oxygen and nitrogen, which is beneficial to reducing the use cost of the fuel cell.

[0108] The gas supply system of the fuel cell 200 provided in the embodiment of the present application is further described below in conjunction with two specific embodiments.

[0109] First embodiment:

[0110] The existing proton exchange membrane fuel cell stack is supplied by a mixture of high-purity nitrogen and high-purity oxygen. The oxygen concentration is controlled to be similar to the oxygen concentration in the air, and the oxygen concentration value varies from 21% to 25%. The control value is 23%. Oxygen and nitrogen are supplied by high-purity oxygen cylinders and high-purity nitrogen cylinders. The supply pressure is not less than 0.2MPa, and air is not used for supply. The flow rate of oxygen and nitrogen is controlled to be 18Nm 3 / h and 60Nm 3 / h, at this time, effective cathode gas supply can be achieved for the fuel cell stack.

[0111] Second embodiment:

[0112] The existing proton exchange membrane fuel cell stack is supplied by a mixture of high-purity nitrogen, high-purity oxygen and air. The oxygen concentration is controlled to be similar to the oxygen concentration in the air, and the oxygen concentration value varies from 21% to 25%. The control value is 23%. Oxygen and nitrogen are supplied by high-purity oxygen cylinders and high-purity nitrogen cylinders, and the supply pressure is not less than 0.2MPa. Air is supplied by an air compressor. The flow rate of oxygen and nitrogen is controlled to be 20Nm 3 / h and 75Nm 3 / h, air flow rate is about 150Nm 3 / h, at this time, effective cathode gas supply can be achieved for the fuel cell stack. At this time, if the supply of hydrogen is guaranteed to be around 40Nm3 / h, effective consumption of the mixed gas can be achieved, and a stable supply of electric energy can be achieved.

[0113] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application is described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A fuel cell gas supply system, characterized in that: include: An oxygen supply module, comprising an oxygen source, wherein the oxygen source is used to provide oxygen; A nitrogen supply module, comprising a nitrogen source, wherein the nitrogen source is used to provide nitrogen; A gas mixing module is connected to the oxygen supply module and the nitrogen supply module respectively, and the gases are mixed in the gas mixing module to obtain a mixed gas; the gas mixing module is also connected to the cathode of the fuel cell to supply the mixed gas to the fuel cell.

2. The fuel cell gas supply system according to claim 1, characterized in that: The oxygen supply module further comprises a first decompression unit, which is disposed downstream of the oxygen source and is used to control the supply pressure of the oxygen source; and / or, The oxygen supply module further includes a first flow control unit, which is disposed downstream of the oxygen source and is used to control the supply flow of the oxygen source.

3. The fuel cell gas supply system according to claim 1, characterized in that: The nitrogen supply module further includes a second decompression unit, which is disposed downstream of the nitrogen source and is used to control the supply pressure of the nitrogen source; and / or, The nitrogen supply module further includes a second flow control unit, which is disposed downstream of the nitrogen source and is used to control the supply flow of the nitrogen source.

4. The fuel cell gas supply system according to claim 1, characterized in that: The gas supply system further includes an air supply module, which is in communication with the gas mixing module and is used to provide air to the gas mixing module, wherein the mixed gas includes the air.

5. The fuel cell gas supply system according to claim 4, characterized in that: The air supply module includes an air compressor and a third flow control unit. The inlet of the air compressor is connected to the atmosphere, and the outlet is connected to the gas mixing module through the third flow control unit. The third flow control unit is used to control the supply flow of the air.

6. The fuel cell gas supply system according to claim 4, characterized in that: The gas mixing module includes a gas mixing unit and a gas storage unit which are interconnected. The gas mixing unit is respectively connected to the oxygen supply module, the nitrogen supply module and the air supply module, and can mix the oxygen, the nitrogen and the air to obtain the mixed gas; the gas storage unit is used to store the mixed gas and can supply the mixed gas to the fuel cell.

7. The fuel cell gas supply system according to claim 6, characterized in that: The gas mixing module further includes a circulation pipeline and a driving member, wherein two ends of the circulation pipeline are respectively connected to two different positions of the gas storage unit, and the driving member is arranged on the circulation pipeline and can drive the mixed gas to flow from one end of the circulation pipeline to the other end; and / or, The gas circulation module further includes an oxygen concentration monitoring component, which is used to monitor the oxygen concentration of the mixed gas in the gas storage unit.

8. The fuel cell gas supply system according to claim 6, characterized in that: The gas circulation module further includes a pressure relief pipeline and a pressure relief valve. One end of the pressure relief pipeline is connected to the gas storage unit, and the other end is connected to the outside of the gas storage unit. The pressure relief valve is arranged on the pressure relief pipeline.

9. The fuel cell gas supply system according to claim 8, characterized in that: The gas circulation module further comprises a pressure monitoring component, wherein the pressure monitoring component is used to monitor the pressure of the mixed gas in the gas storage unit; and / or, The air supply module comprises an air compressor, an inlet of the air compressor is communicated with the atmosphere, an outlet of the air compressor is communicated with the gas mixing unit, and the other end of the pressure relief pipeline is communicated with the inlet of the air compressor.

10. The fuel cell gas supply system according to claim 1, characterized in that: The oxygen provided by the oxygen source is high-purity oxygen; and / or, The nitrogen provided by the nitrogen source is high-purity nitrogen; and / or, The fuel cell is a proton exchange membrane fuel cell.

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