Coaxial tube type fuel cell single chip test system

Abstract

The application provides a coaxial tube type fuel cell single chip test system, which comprises an anode pipeline, an anode coaxial pipeline, a cathode pipeline, a cathode coaxial pipeline and a liquid cooling machine; the anode pipeline is communicated with the anode coaxial pipeline, and the anode coaxial pipeline is communicated with a reactor anode inlet; the cathode pipeline is communicated with the cathode coaxial pipeline, and the cathode coaxial pipeline is communicated with a reactor cathode inlet; the anode coaxial pipeline is communicated with the cathode coaxial pipeline and the cathode pipeline; and the liquid cooling machine is communicated with the cathode pipeline, the cathode coaxial pipeline, the anode pipeline and the anode coaxial pipeline. The application comprises high-temperature and low-temperature control functions, and solves the influence of external environment on the temperature in the pipeline when the flow is very small.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and more specifically, to a coaxial tube-based fuel cell monolithic testing system. Background Technology

[0002] The proton exchange membrane (PEMFC) is a key material in proton exchange membrane fuel cells (PEMFCs), with a chemical structure consisting of a fluorocarbon backbone and side chains containing sulfonic acid groups. Since its proton conduction relies on water molecules, its proton conductivity decreases significantly above 80°C. Another type of PEMFC, the phosphate membrane, can withstand temperatures up to 200°C, but it also requires high-temperature testing. Furthermore, low-temperature PEMFCs involve complex water / thermal management issues and catalyst poisoning. Increasing the PEMFC operating temperature is crucial. During cold start-up at temperatures below 0°C, water generated in the cathode reaction easily freezes, causing blockage of the catalyst and diffusion layers, hindering the reaction. The volume change caused by water freezing also damages the membrane electrode assembly structure, reducing fuel cell performance. Therefore, high and low temperature testing of the proton exchange membrane is of paramount importance for optimizing this component.

[0003] During high and low temperature gas supply tests of fuel cell proton exchange membranes, the proton exchange membranes are often tested as single pieces ranging from 5cm*5cm to 10cm*10cm in size, resulting in a very small overall gas supply flow rate. This leads to slow flow velocity and low heat carrying capacity in the pipeline. The flow is easily affected by the external ambient temperature and heat absorption of the pipeline wall. Even when heated to 350℃, the temperature can drop below 80℃ after flowing in a 1m long pipeline. Even with insulation, it is still difficult to reach temperatures above 150℃. Therefore, insulation or heat preservation methods are needed to achieve high and low temperature testing. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the purpose of this invention is to provide a coaxial tube-based fuel cell monolithic testing system.

[0005] A single-cell fuel cell testing system based on a coaxial tube configuration according to the present invention includes: an anode tube, an anode coaxial tube, a cathode tube, a cathode coaxial tube, and a liquid cooler;

[0006] The anode pipeline is connected to the anode coaxial pipeline, and the anode coaxial pipeline is connected to the reactor anode inlet; the cathode pipeline is connected to the cathode coaxial pipeline, and the cathode coaxial pipeline is connected to the reactor cathode inlet;

[0007] The anode coaxial pipeline is connected to the cathode coaxial pipeline and the cathode pipeline; the liquid chiller is connected to the cathode pipeline, the cathode coaxial pipeline, the anode pipeline and the anode coaxial pipeline.

[0008] Preferably, the anode pipeline is provided with an anode pretreatment system, an anode mass flow controller, an anode electric three-way valve, and an anode precooling system in sequence along the air inlet direction;

[0009] The anode precooling system is connected to the anode coaxial pipeline and the liquid chiller.

[0010] Preferably, the anode pipeline is further provided with an anode heating system;

[0011] The two ends of the anode heating system are respectively connected to the anode electric three-way valve and the anode coaxial pipeline.

[0012] Preferably, the anode coaxial pipeline is equipped with an anode coaxial tube float flow meter, an anode coaxial tube electric three-way valve, and an anode coaxial tube precooling system along the air inlet direction;

[0013] The anode coaxial tube float flowmeter is connected to the cathode coaxial pipeline and the cathode pipeline, and the anode coaxial tube precooling system is connected to the reactor anode inlet.

[0014] Preferably, the anode coaxial pipe is further provided with an anode coaxial pipe heating system;

[0015] The two ends of the anode coaxial tube heating system are respectively connected to the anode coaxial tube electric three-way valve and the reactor anode inlet.

[0016] Preferably, the cathode pipeline is provided with a cathode pretreatment system, a cathode mass flow controller, an anode electric three-way valve, and a cathode precooling system in sequence along the air inlet direction;

[0017] The cathode pretreatment system is connected to the cathode coaxial pipeline and the anode coaxial pipeline; the cathode precooling system is connected to the liquid chiller and the cathode coaxial pipeline.

[0018] Preferably, a cathode heating system is also provided on the cathode pipeline;

[0019] The two ends of the cathode heating system are respectively connected to the electric three-way valve and the cathode coaxial pipeline.

[0020] Preferably, the cathode coaxial pipeline is provided with a cathode coaxial tube float flow meter, a cathode coaxial tube electric three-way valve, and a cathode coaxial tube precooling system in sequence along the air inlet direction;

[0021] The cathode coaxial tube float flowmeter is connected to the anode coaxial pipeline and the cathode pipeline; the cathode coaxial tube precooling system is connected to the reactor cathode inlet.

[0022] Preferably, a cathode coaxial tube heating system is also provided on the cathode coaxial tube;

[0023] The two ends of the cathode coaxial tube heating system are respectively connected to the cathode coaxial tube electric three-way valve and the reactor cathode inlet.

[0024] Preferably, an anode coaxial tube inlet temperature sensor and an anode inlet temperature sensor are provided at one end of the anode coaxial tube near the reactor anode inlet;

[0025] The cathode coaxial pipe is equipped with a cathode coaxial pipe inlet temperature sensor and a cathode inlet temperature sensor at one end near the reactor cathode inlet.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The system of the present invention includes two control functions: high temperature and low temperature, which solves the problem of the influence of the external environment on the temperature inside the pipe when the flow rate is extremely low;

[0028] 2. This invention ensures that high and low temperature tests can be performed on proton exchange membranes at extremely low gas flow rates, while also having a precise flow rate control function;

[0029] 3. In this invention, the gas flow rate inside the coaxial tube can be controlled by a float flow meter. The gas inside the coaxial tube is air. The cold or heat carried by this gas can quickly change the temperature of the inner tube wall, thereby reducing the heat absorption of the stainless steel tube wall and making the temperature of the inner tube wall infinitely close to the temperature of the internal gas. This prevents the flow of low-temperature or high-temperature gas inside the inner tube from being affected by temperature interference, and ensures the temperature control accuracy and effect during testing. Attached Figure Description

[0030] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0031] Figure 1 This is a schematic diagram of the structural principle of the coaxial tube-based fuel cell monolithic testing system of the present invention;

[0032] Figure 2 This is a schematic diagram of the anode pretreatment system.

[0033] The diagram shows:

[0034] Anode pretreatment system 1, Cathode mass flow controller 13

[0035] Anode mass flow controller 2, Cathode electric three-way valve 14

[0036] Anode electric three-way valve 3; Cathode precooling system 15

[0037] Anode precooling system 4; Cathode heating system 16

[0038] Anode heating system 5 Cathode coaxial tube inlet temperature sensor 17

[0039] Anode coaxial tube inlet temperature sensor 6; Cathode inlet temperature sensor 18

[0040] Anode inlet temperature sensor 7, Cathode coaxial tube float flowmeter 19

[0041] Anode coaxial tube float flowmeter 8; Cathode coaxial tube electric three-way valve 20

[0042] 9. Electric three-way valve for anode coaxial tube; 21. Cathode coaxial tube precooling system.

[0043] Anode coaxial tube precooling system 10; Cathode coaxial tube heating system 22

[0044] Anode coaxial tube heating system 11 Liquid cooler 23

[0045] Cathode pretreatment system 12 Detailed Implementation

[0046] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0047] Example 1:

[0048] like Figure 1 As shown, this embodiment provides a single-cell fuel cell testing system using a coaxial tube configuration, including: an anode tube, an anode coaxial tube, a cathode tube, a cathode coaxial tube, and a liquid cooler 23. The anode tube is connected to the anode coaxial tube, the anode coaxial tube is connected to the reactor anode inlet, the cathode tube is connected to the cathode coaxial tube, the cathode coaxial tube is connected to the reactor cathode inlet, the anode coaxial tube is connected to the cathode coaxial tube and the cathode tube, and the liquid cooler 23 is connected to the cathode tube, the cathode coaxial tube, the anode tube, and the anode coaxial tube.

[0049] Along the air inlet direction, the anode pipeline is sequentially equipped with an anode pretreatment system 1, an anode mass flow controller 2, an anode electric three-way valve 3, and an anode precooling system 4. The anode precooling system 4 is connected to the anode coaxial pipeline and the liquid chiller 23. An anode heating system 5 is also installed on the anode pipeline, with its two ends connected to the anode electric three-way valve 3 and the anode coaxial pipeline, respectively.

[0050] Along the air inlet direction, the cathode pipeline is sequentially equipped with a cathode pretreatment system 12, a cathode mass flow controller 13, a cathode electric three-way valve 14, and a cathode precooling system 15. The cathode pretreatment system 12 is connected to the cathode coaxial pipeline and the anode coaxial pipeline; the cathode precooling system 15 is connected to the liquid chiller 23 and the cathode coaxial pipeline. A cathode heating system 16 is also installed on the cathode pipeline, with its two ends connected to the cathode electric three-way valve 14 and the cathode coaxial pipeline, respectively.

[0051] An anode coaxial tube float flowmeter 8, an anode coaxial tube electric three-way valve 9, and an anode coaxial tube precooling system 10 are installed along the intake direction on the anode coaxial tube. The anode coaxial tube float flowmeter 8 is connected to the cathode coaxial tube and the cathode tube. The anode coaxial tube precooling system 10 is connected to the reactor anode inlet. An anode coaxial tube heating system 11 is also installed on the anode coaxial tube, with its two ends connected to the anode coaxial tube electric three-way valve 9 and the reactor anode inlet, respectively. An anode coaxial tube inlet temperature sensor 6 and an anode inlet temperature sensor 7 are installed on the anode coaxial tube near the reactor anode inlet.

[0052] Along the inlet direction, the cathode coaxial pipeline is sequentially equipped with a cathode coaxial tube float flowmeter 19, a cathode coaxial tube electric three-way valve 20, and a cathode coaxial tube precooling system 21. The cathode coaxial tube float flowmeter 19 is connected to the anode coaxial pipeline and the cathode pipeline; the cathode coaxial tube precooling system 21 is connected to the reactor cathode inlet. A cathode coaxial tube heating system 22 is also installed on the cathode coaxial pipeline, with its two ends connected to the cathode coaxial tube electric three-way valve 20 and the reactor cathode inlet, respectively. A cathode coaxial tube inlet temperature sensor 17 and a cathode inlet temperature sensor 18 are installed on the cathode coaxial pipeline near the reactor cathode inlet.

[0053] The outlet of the anode pretreatment system 1 is connected to the inlet of the anode mass flow controller 2. The outlet of the anode mass flow controller 2 is connected to the inlet of the anode electric three-way valve 3. The first outlet of the anode electric three-way valve 3 is connected to the first inlet of the anode precooling system 4. The second outlet of the anode electric three-way valve 3 is connected to the inlet of the anode heating system 5. The first outlet of the anode precooling system 4 and the outlet of the anode heating system 5 are connected to the reactor anode inlet.

[0054] The outlet of the cathode pretreatment system 12 is connected to the inlet of the anode coaxial tube float flowmeter 8, the inlet of the cathode coaxial tube float flowmeter 19, and the inlet of the cathode mass flow controller 13. The outlet of the cathode mass flow controller 13 is connected to the inlet of the cathode electric three-way valve 14. The first outlet of the cathode electric three-way valve 14 is connected to the first inlet of the cathode precooling system 15. The second outlet of the cathode electric three-way valve 14 is connected to the inlet of the cathode heating system 16. The outlets of the cathode precooling system 15 and the cathode heating system 16 are connected to the reactor cathode inlet.

[0055] The outlet end of the cathode coaxial tube float flowmeter 19 is connected to the inlet end of the cathode coaxial tube electric three-way valve 20. The first outlet end of the cathode coaxial tube electric three-way valve 20 is connected to the first inlet end of the cathode coaxial tube precooling system 21. The second outlet end of the cathode coaxial tube electric three-way valve 20 is connected to the inlet end of the cathode coaxial tube heating system 22. The first outlet end of the cathode coaxial tube precooling system 21 and the outlet end of the cathode coaxial tube heating system 22 are connected to the reactor cathode inlet.

[0056] The outlet end of the anode coaxial tube float flowmeter 8 is connected to the inlet end of the anode coaxial tube electric three-way valve 9. The first outlet end of the anode coaxial tube electric three-way valve 9 is connected to the first inlet end of the anode coaxial tube precooling system 10. The second outlet end of the anode coaxial tube electric three-way valve 9 is connected to the inlet end of the anode coaxial tube heating system 11. The first outlet end of the anode coaxial tube precooling system 10 and the outlet end of the anode coaxial tube heating system 11 are connected to the reactor anode inlet.

[0057] The liquid chiller 23 is connected to the second inlet end and the second outlet end of the anode precooling system 4, the second inlet end and the second outlet end of the cathode precooling system 15, the second inlet end and the second outlet end of the anode coaxial tube precooling system 10, and the second inlet end and the second outlet end of the cathode coaxial tube precooling system 21.

[0058] The anode coaxial tube inlet temperature sensor 6 and the anode inlet temperature sensor 7 are located near the reactor anode inlet. The exhaust gas from the anode precooling system 4, the anode heating system 5, the anode coaxial tube precooling system 10, and the anode coaxial tube heating system 11 passes through the anode coaxial tube inlet temperature sensor 6 and the anode inlet temperature sensor 7 in sequence before entering the reactor anode inlet.

[0059] The cathode coaxial tube inlet temperature sensor 17 and the cathode inlet temperature sensor 18 are located near the reactor cathode inlet. The exhaust gas from the cathode precooling system 15, the cathode heating system 16, the cathode coaxial tube precooling system 21, and the cathode coaxial tube heating system 22 passes through the cathode coaxial tube inlet temperature sensor 17 and the cathode inlet temperature sensor 18 in sequence before entering the reactor cathode inlet.

[0060] like Figure 2 As shown, the anode pretreatment system 1 provides hydrogen supply, including a hydrogen delivery pipe and a pressure reducing valve, filter, and solenoid valve installed on the hydrogen delivery pipe. The gas inlet is first a filter to remove gas impurities, followed by a pressure reducing valve to control the inlet pressure, and then a solenoid valve to control the gas path switch. Anode mass flow controller 2 controls the hydrogen flow rate. Anode electric three-way valve 3 controls the flow rate of the hot and cold mixture. Anode precooling system 4 is a hydrogen precooling (cooling) treatment device and monitors the temperature after precooling. Anode heating system 5 is a hydrogen heating (heating) treatment device and monitors the temperature after heating.

[0061] Anode coaxial tube inlet temperature sensor 6: Detects the inlet temperature of the fuel cell coaxial tube. Anode inlet temperature sensor 7: Detects the inlet temperature of the fuel cell anode.

[0062] Anode coaxial tube float flowmeter 8: Used to control the gas flow rate in the coaxial tube jacket, typically 10 to 15 times the maximum controllable gas flow rate inside the anode. Anode coaxial tube electric three-way valve 9: Detects the anode outlet pressure of the fuel cell stack. Anode coaxial tube precooling system 10: Includes a plate heat exchanger and related temperature sensors. The coaxial tube gas enters the hot side of the plate heat exchanger and exchanges heat with the cold side coolant, reaching a minimum temperature of -60°C. Anode coaxial tube heating system 11: Includes a heater, power regulator, and related temperature sensors. The coaxial tube gas enters the heater and can reach a maximum temperature of 300°C.

[0063] Cathode pretreatment system 12: Provides air supply, including an air delivery pipe and a pressure reducing valve, filter, and solenoid valve installed on the air delivery pipe. The gas inlet is first a filter to remove gas impurities, followed by a pressure reducing valve to control the inlet pressure, and then a solenoid valve to control the gas path switch. The cathode pretreatment system 12 has the same structure as the anode pretreatment system 1. Cathode mass flow controller 13: Controls the air flow rate. Cathode electric three-way valve 14: Controls the flow rate of the hot and cold mixture. Cathode precooling system 15: An air precooling (cooling) treatment device and monitors the temperature after precooling. Cathode heating system 16: An air heating (heating) treatment device and monitors the temperature after heating.

[0064] Cathode coaxial tube inlet temperature sensor 17: detects the inlet temperature of the fuel cell coaxial tube. Cathode inlet temperature sensor 18: detects the inlet temperature of the fuel cell cathode.

[0065] Cathode coaxial tube float flowmeter 19: Used to control the gas flow rate in the coaxial tube interlayer, typically 10-15 times the maximum controllable gas flow rate inside the cathode. Cathode coaxial tube electric three-way valve 20: Detects the cathode outlet pressure of the fuel cell stack. Cathode coaxial tube precooling system 21: Includes a plate heat exchanger and related temperature sensors. The coaxial tube gas enters the hot side of the plate heat exchanger and exchanges heat with the cold side coolant, reaching a minimum temperature of -60°C. Cathode coaxial tube heating system 22: Includes a heater, power regulator, and related temperature sensors. The coaxial tube gas enters the heater and can reach a maximum temperature of 300°C.

[0066] Liquid chiller 23: Provides ultra-low temperature coolant to cool the gas.

[0067] The gas first undergoes pressure reduction and filtration in the main pretreatment system. The gas flow rate required by the anode or cathode is controlled by the main mass flow controller. Based on the current set gas temperature, the main electric three-way valve controls the gas distribution. Part of the gas enters the main precooling system, and part of the gas enters the main heating system. After passing through the two systems, the gas is mixed to reach a temperature close to the set temperature. The gas in the coaxial tubes of the cathode and anode is all air. The air flow rate is controlled by a float flow meter and is 10 to 15 times the maximum flow rate of the main mass flow controller. Similarly, the air enters the coaxial tube precooling system and coaxial tube heating system through the three-way valve. Through mixing, the air reaches a temperature close to the set temperature. The internal pipeline wall temperature is controlled and insulated.

[0068] Example 2:

[0069] Those skilled in the art can understand this embodiment as a more specific description of Embodiment 1.

[0070] This embodiment provides a fuel cell single-cell testing system capable of high and low temperature operation, including an anode main circuit pretreatment system, an anode main circuit mass flow controller, an anode main circuit electric three-way valve, an anode main circuit precooling system, an anode main circuit heating system, an anode coaxial tube inlet temperature sensor, an anode inlet temperature sensor, an anode coaxial tube float flow meter, an anode coaxial tube electric three-way valve, an anode coaxial tube heater, an anode coaxial tube precooling system, a cathode main circuit pretreatment system, a cathode main circuit mass flow controller, a cathode main circuit electric three-way valve, a cathode main circuit precooling system, a cathode main circuit heating system, a cathode coaxial tube inlet temperature sensor, a cathode inlet temperature sensor, a cathode coaxial tube float flow meter, a cathode coaxial tube electric three-way valve, a cathode coaxial tube heater, a cathode coaxial tube precooling system, and a refrigerator.

[0071] The anode pretreatment system 1 includes a hydrogen delivery pipe and a pressure reducing valve, filter, and solenoid valve installed on the hydrogen delivery pipe. After the hydrogen passes through the pressure reducing valve and filter to regulate pressure and remove impurities, the flow rate is controlled by the solenoid valve. The anode mass flow controller 2 is used to control the total gas flow rate. The anode electric three-way valve 3 is used to distribute the high-temperature and low-temperature gas flow rates for temperature mixing. The anode precooling system 4 includes a plate heat exchanger and related temperature sensors. Hydrogen enters the hot side of the plate heat exchanger and exchanges heat with the cold side coolant, reaching a minimum temperature of -60°C. The anode heating system 5 includes a heater, a power regulator, and related temperature sensors. Hydrogen enters the heater and can reach a maximum temperature of 300°C.

[0072] Anode coaxial tube inlet temperature sensor 6 is used to detect the temperature of the coaxial tube jacket. Anode inlet temperature sensor 7 is used to detect the fuel cell stack inlet temperature.

[0073] The anode coaxial tube float flowmeter 8 is used to control the gas flow rate in the coaxial tube jacket, typically 10-15 times the maximum controllable gas flow rate inside the anode. The anode coaxial tube electric three-way valve 9 is used to distribute the high-temperature and low-temperature gas flow rates within the coaxial tube for temperature mixing. The anode coaxial tube pre-cooling system 10 includes a plate heat exchanger and related temperature sensors. The coaxial tube gas enters the hot side of the plate heat exchanger and exchanges heat with the cold-side coolant, reaching a minimum temperature of -60°C. The anode coaxial tube heating system 11 includes a heater, a power regulator, and related temperature sensors. The coaxial tube gas enters the heater and can reach a maximum temperature of 300°C.

[0074] The cathode pretreatment system 12 includes a hydrogen delivery pipe and a pressure reducing valve, a filter, and a solenoid valve installed on the hydrogen delivery pipe. After the hydrogen passes through the pressure reducing valve and the filter to regulate its pressure and filter out impurities, the flow rate is controlled by the solenoid valve. The cathode mass flow controller 13 is used to control the total gas flow rate. The cathode electric three-way valve 14 is used to distribute the high-temperature and low-temperature gas flow rates and to mix them. The cathode precooling system 15 includes a plate heat exchanger and related temperature sensors. Hydrogen enters the hot side of the plate heat exchanger and exchanges heat with the cold side coolant, reaching a minimum temperature of -60°C. The cathode heating system 16 includes a heater, a power regulator, and related temperature sensors. Hydrogen enters the heater and can reach a maximum temperature of 300°C.

[0075] The cathode coaxial tube inlet temperature sensor 17 is used to detect the temperature of the coaxial tube interlayer. The cathode inlet temperature sensor 18 is used to detect the fuel cell stack inlet temperature.

[0076] The cathode coaxial tube float flowmeter 19 is used to control the gas flow rate in the coaxial tube interlayer, typically 10 to 15 times the maximum controllable gas flow rate inside the cathode. The cathode coaxial tube electric three-way valve 20 is used to distribute the high-temperature and low-temperature gas flow rates within the coaxial tube for temperature mixing. The cathode coaxial tube pre-cooling system 21 includes a plate heat exchanger and related temperature sensors. The coaxial tube gas enters the hot side of the plate heat exchanger and exchanges heat with the cold-side coolant, reaching a minimum temperature of -60°C. The cathode coaxial tube heating system 22 includes a heater, a power regulator, and related temperature sensors. The coaxial tube gas enters the heater and can reach a maximum temperature of 300°C.

[0077] The liquid chiller 23 provides ultra-low temperature coolant to cool the gas.

[0078] The system in this embodiment ensures that high and low temperature tests can be performed on proton exchange membranes at extremely low gas flow rates, while also having precise flow control capabilities.

[0079] During use, due to the slow cooling and heating rates of the liquid chiller (1-2℃ / m11) and the slow heating rate of the heater (2-3℃ / m11) and poor dynamic control, in order to meet the actual temperature change rate, the liquid chiller (23) directly controls the cooling to the lowest temperature (-70℃) after the system is started, and starts the circulation with the plate heat exchanger. The heater (5 / 16) heats up to the required temperature (260℃). By changing the opening of the electric three-way valve (3 / 14), the mixing of hot and cold gases is achieved to realize the precise control of the overall temperature and the change rate of temperature change.

[0080] The gas temperature control method inside the coaxial tube is the same as that for the main gas temperature control.

[0081] As a preferred technical solution, each pipeline is also equipped with corresponding conventional pipeline fittings such as filters, check valves, and pressure relief valves.

[0082] Since proton exchange membrane tests often involve single membranes ranging from 5cm*5cm to 10cm*10cm in size, the overall gas supply flow rate is very small, resulting in slow flow velocity and low heat carrying capacity in the pipeline. During flow, it is easily affected by the external ambient temperature and heat absorption of the pipeline wall. Typically, when testing a 100W single membrane, the anode gas flow rate is usually 0.2-3 NLPM, and the cathode gas flow rate is usually 0.3-8 NLPM.

[0083] When the set temperature is lower than the ambient temperature, typically below freezing, the temperature inside the coaxial tube remains 2-5°C lower than the set temperature. When the set temperature is higher than the ambient temperature, typically between 80 and 250°C, the temperature inside the coaxial tube remains 5-10°C higher than the set temperature. Simultaneously, the gas flow rate inside the coaxial tube can be controlled by a float flowmeter, typically 10-15 times the full flow rate of the proton exchange membrane during testing. The gas inside the coaxial tube is air; the cold or heat carried by this gas can quickly change the temperature of the inner tube wall, thereby reducing the heat absorption of the stainless steel tube wall and bringing the inner tube wall temperature infinitely close to the internal gas temperature. This prevents temperature interference from low-temperature or high-temperature gas flow within the inner tube, ensuring the accuracy and effectiveness of temperature control during testing.

[0084] This invention includes both high-temperature and low-temperature control functions, which solves the problem of the influence of the external environment on the temperature inside the pipe when the flow rate is extremely low.

[0085] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0086] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A single-cell fuel cell testing system using a coaxial tube design, characterized in that, include: Anode piping, anode coaxial piping, cathode piping, cathode coaxial piping, and liquid cooler (23); The anode pipeline is connected to the anode coaxial pipeline to form an internal pipeline and a coaxial pipeline, and the anode coaxial pipeline is connected to the reactor anode inlet; the cathode pipeline is connected to the cathode coaxial pipeline to form an internal pipeline and a coaxial pipeline, and the cathode coaxial pipeline is connected to the reactor cathode inlet. The anode coaxial pipeline is connected to the cathode coaxial pipeline and the cathode pipeline; the liquid cooler (23) is connected to the cathode pipeline, the cathode coaxial pipeline, the anode pipeline and the anode coaxial pipeline; The anode pipeline is provided with an anode pretreatment system (1), an anode mass flow controller (2), an anode electric three-way valve (3), and an anode precooling system (4) in sequence along the air inlet direction. The anode precooling system (4) is connected to the anode coaxial pipeline and the liquid cooler (23); The anode coaxial pipe is equipped with an anode coaxial pipe float flow meter (8), an anode coaxial pipe electric three-way valve (9), and an anode coaxial pipe precooling system (10) along the air inlet direction. The anode coaxial tube float flowmeter (8) is connected to the cathode coaxial pipeline and the cathode pipeline, and the anode coaxial tube precooling system (10) is connected to the reactor anode inlet; The cathode pipeline is provided with a cathode pretreatment system (12), a cathode mass flow controller (13), a cathode electric three-way valve (14), and a cathode precooling system (15) in sequence along the air inlet direction. The cathode pretreatment system (12) is connected to the cathode coaxial pipeline and the anode coaxial pipeline; the cathode precooling system (15) is connected to the liquid cooler (23) and the cathode coaxial pipeline; The cathode coaxial pipe is sequentially equipped with a cathode coaxial pipe float flow meter (19), a cathode coaxial pipe electric three-way valve (20), and a cathode coaxial pipe precooling system (21) along the air inlet direction. The cathode coaxial tube float flowmeter (19) is connected to the anode coaxial pipeline and the cathode pipeline; the cathode coaxial tube precooling system (21) is connected to the reactor cathode inlet.

2. The coaxial tube-based fuel cell monolithic testing system according to claim 1, characterized in that, An anode heating system (5) is also provided on the anode pipeline; The two ends of the anode heating system (5) are respectively connected to the anode electric three-way valve (3) and the anode coaxial pipeline.

3. The fuel cell monolithic testing system using a coaxial tube configuration according to claim 1, characterized in that, An anode coaxial tube heating system (11) is also provided on the anode coaxial tube. The two ends of the anode coaxial tube heating system (11) are respectively connected to the anode coaxial tube electric three-way valve (9) and the reactor anode inlet.

4. The fuel cell monolithic testing system using a coaxial tube configuration according to claim 1, characterized in that, A cathode heating system (16) is also provided on the cathode pipeline. The two ends of the cathode heating system (16) are respectively connected to the cathode electric three-way valve (14) and the cathode coaxial pipeline.

5. The fuel cell monolithic testing system using a coaxial tube configuration according to claim 1, characterized in that, A cathode coaxial tube heating system (22) is also provided on the cathode coaxial tube. The two ends of the cathode coaxial tube heating system (22) are respectively connected to the cathode coaxial tube electric three-way valve (20) and the reactor cathode inlet.

6. The coaxial tube-based fuel cell monolithic testing system according to claim 1, characterized in that, A coaxial tube inlet temperature sensor (6) and an anode inlet temperature sensor (7) are installed at one end of the anode coaxial tube near the reactor anode inlet. The cathode coaxial tube is equipped with a cathode coaxial tube inlet temperature sensor (17) and a cathode inlet temperature sensor (18) at the end near the reactor cathode inlet.

Images