Fuel cell low-temperature thermal management system and method with external catalytic reactor

Abstract

The present invention proposes a low-temperature thermal management system and method for a fuel cell with an external catalytic reactor, which relates to the field of fuel cell technology. A high-efficiency heat exchanger is provided at the air inlet end of the fuel cell. The positive electrode of the fuel cell is connected to the anode air supply channel, and the negative electrode is connected to the cathode air supply channel. The anode air supply channel and the cathode air supply channel pass through the interior of the high-efficiency heat exchanger. A hydrogen-oxygen catalytic reactor is provided at the air outlet end of the fuel cell. The positive and negative electrodes of the fuel cell are respectively connected to the hydrogen-oxygen catalytic reactor. The hydrogen-oxygen catalytic reactor is connected to the high-efficiency heat exchanger through a high-temperature gas mixing channel. A hydrogen circuit is provided outside the positive electrode of the fuel cell, and a first control valve and a second control valve are respectively provided on the anode air supply channel and the anode air outlet channel. By using an external hydrogen-oxygen catalytic reactor, catalytic combustion of the exhaust gas of the fuel cell is used to achieve thermal management in a low-temperature environment. No externally powered electric heating system is required to achieve a cold start of the fuel cell.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a low-temperature thermal management system and method for a fuel cell with an external catalytic reactor. Background Art

[0002] A fuel cell is a device that converts the chemical energy in a fuel directly into electrical energy. It is widely used in automobiles, ships, power plants, and other fields. When a fuel cell is operating, hydrogen and air are introduced into the anode and cathode of the fuel cell, respectively, where an electrochemical reaction occurs to generate electricity.

[0003] Fuel cell systems must be capable of starting and operating stably in sub-zero temperatures due to their environmental requirements. Many patents address the catalytic reactions that occur within the cell, making them unable to achieve temperature control during operation. This is detrimental to fuel cell operation in low-temperature environments. To address the sub-zero starting issue, researchers have explored methods such as stack self-heating without an external heat source, external insulation-assisted low-temperature starting, and external heat source-assisted low-temperature starting. Starting without an external heat source requires precise gas and power control, resulting in the possibility of startup failure and difficulty in repeating a failed startup. Low-temperature starting with external insulation is limited by storage conditions and time. If stored at low temperatures for extended periods, the system temperature may drop too low, leading to startup failure. Low-temperature starting with an external heat source requires additional external auxiliary equipment, but offers stable starting performance and a low risk of failure after startup. The external heat source can be stored electrical energy, thermal energy, or other energy sources that can be converted to heat.

[0004] In view of the shortcomings of the existing technology, it is necessary to provide a fuel cell low-temperature thermal management system and method with an external catalytic reactor that can solve the problems raised in the above background technology. Summary of the Invention

[0005] The purpose of the present invention is to provide a low-temperature thermal management system and method for a fuel cell with an external catalytic reactor, which can propose solutions to the shortcomings of the existing technology, use catalytic combustion of the exhaust gas of the fuel cell to achieve thermal management in a low-temperature environment, improve the energy efficiency of the system, and at the same time enable temperature control to be achieved through catalytic reaction during the operation of the fuel cell. There is no need for an externally powered electric heating system, and the parasitic power is low.

[0006] An embodiment of the present invention provides a fuel cell low-temperature thermal management system with an external catalytic reactor, comprising a fuel cell, wherein a high-efficiency heat exchanger is provided at the air inlet end of the fuel cell, the positive electrode of the fuel cell is connected to the anode air supply channel, the negative electrode of the fuel cell is connected to the cathode air supply channel, and the anode air supply channel and the cathode air supply channel pass through the interior of the high-efficiency heat exchanger;

[0007] The fuel cell is provided with a hydrogen-oxygen catalytic reactor at the gas outlet end. The positive electrode and negative electrode of the fuel cell are connected to the hydrogen-oxygen catalytic reactor through the anode gas outlet channel and the cathode gas outlet channel respectively. The hydrogen-oxygen catalytic reactor is connected to the high-efficiency heat exchanger through the high-temperature gas mixing channel.

[0008] A hydrogen circuit is provided outside the positive electrode of the fuel cell, and the two ends of the hydrogen circuit are respectively connected to the anode gas supply channel and the anode gas outlet channel. A first control valve and a second control valve are respectively provided on the anode gas supply channel and the anode gas outlet channel. The first control valve is provided between the hydrogen circuit and the anode of the fuel cell, and the second control valve is provided between the hydrogen circuit and the hydrogen-oxygen catalytic reactor.

[0009] In some embodiments of the present invention, the air inlet end of the high-efficiency heat exchanger is connected to the air outlet end of the high-temperature gas mixing channel, and the air outlet end of the high-efficiency heat exchanger extends to an external device through an external pipeline.

[0010] In some embodiments of the present invention, the hydrogen exhaust gas outlet of the positive terminal of the fuel cell is connected to the hydrogen-oxygen catalytic reactor through an exhaust gas pipeline, and a third control valve is provided at the hydrogen exhaust gas outlet.

[0011] In some embodiments of the present invention, a gas-water separator is provided on the cathode gas outlet channel.

[0012] In some embodiments of the present invention, the first control valve, the second control valve and the third control valve are respectively connected to an external controller, the controller is connected to a temperature sensor, and the temperature sensor is provided in the environment where the fuel cell is located for detecting the ambient temperature.

[0013] In some embodiments of the present invention, rubber sealing rings are provided at the connection between the high-efficiency heat exchanger and the anode gas supply channel, the cathode gas supply channel, and at the connection between the hydrogen-oxygen catalytic reactor and the high-temperature gas mixing channel.

[0014] In some embodiments of the present invention, flow controllers are respectively provided at the gas inlet ends of the anode gas supply channel and the cathode gas supply channel.

[0015] An embodiment of the present invention further provides a low-temperature thermal management method for a fuel cell with an external catalytic reactor, comprising the following steps:

[0016] Air and hydrogen are introduced into the cathode gas supply channel and the anode gas supply channel respectively, and the opening and closing of the first control valve, the second control valve and the third control valve are controlled respectively according to the ambient temperature or the temperature value of the inlet air and hydrogen to realize the temperature control of the fuel cell.

[0017] In some embodiments of the present invention, the step of introducing air and hydrogen into the cathode gas supply channel and the anode gas supply channel, respectively, and controlling the opening and closing of the first control valve, the second control valve, and the third control valve according to the ambient temperature or the temperature of the inlet air and hydrogen, respectively, includes:

[0018] When the ambient temperature or the temperature of the inlet air or hydrogen reaches a preset temperature value, the first control valve is controlled to open, the second control valve is controlled to close, and the third control valve is controlled to close. Hydrogen enters the fuel cell through the anode gas supply channel for reaction and circulates through the hydrogen circuit. Air enters the fuel cell through the cathode gas supply channel for reaction.

[0019] When the ambient temperature or the temperature of the inlet air or hydrogen is lower than the preset temperature value, the first control valve is controlled to close, the second control valve is controlled to open, and the third control valve is controlled to open, hydrogen enters through the anode gas supply channel, passes through the hydrogen loop and enters the hydrogen-oxygen catalytic reactor, and air flows through the cathode gas supply channel and then enters the hydrogen-oxygen catalytic reactor to undergo a catalytic reaction with the hydrogen, thereby generating a high-temperature mixed gas; the high-temperature mixed gas enters the high-efficiency heat exchanger through the high-temperature mixed gas channel to heat the hydrogen and air inside the anode gas supply channel and the cathode gas supply channel, thereby achieving a cold start of the fuel cell;

[0020] When the ambient temperature is too low during the operation of the fuel cell, the third control valve is controlled to open, and the anode hydrogen exhaust gas is discharged into the hydrogen-oxygen catalytic reactor through the exhaust gas pipe, and catalytically reacts with the air at the negative electrode outlet of the fuel cell to generate a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger through the high-temperature mixed gas channel to heat the hydrogen and air inside the anode gas supply channel and the cathode gas supply channel, thereby achieving temperature control of the fuel cell.

[0021] In some embodiments of the present invention, the preset temperature value is -10°C.

[0022] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0023] The present invention uses a fuel cell, wherein an efficient heat exchanger is provided at the air inlet end of the fuel cell, the positive electrode of the fuel cell is connected to the anode air supply channel, and the negative electrode of the fuel cell is connected to the cathode air supply channel, and the anode air supply channel and the cathode air supply channel pass through the interior of the efficient heat exchanger; a hydrogen-oxygen catalytic reactor is provided at the air outlet end of the fuel cell, the positive electrode and the negative electrode of the fuel cell are connected to the hydrogen-oxygen catalytic reactor through the anode air outlet channel and the cathode air outlet channel respectively, and the hydrogen-oxygen catalytic reactor is connected to the efficient heat exchanger through a high-temperature gas mixing channel; a hydrogen circuit is provided outside the positive electrode of the fuel cell, and the two ends of the hydrogen circuit are connected to the anode air supply channel and the anode air outlet channel respectively, and a first control valve and a second control valve are provided on the anode air supply channel and the anode air outlet channel respectively, the first control valve is provided between the hydrogen circuit and the anode of the fuel cell, and the second control valve is provided between the hydrogen circuit and the hydrogen-oxygen catalytic reactor. Through an external hydrogen-oxygen catalytic reactor and a high-efficiency heat exchanger, the exhaust gas of the fuel cell is used for catalytic combustion to achieve thermal management in a low-temperature environment, thereby improving the energy efficiency of the system. The cold start of the fuel cell can be achieved without an externally powered electric heating system. At the same time, the design of the external hydrogen-oxygen catalytic reactor and the third control valve enables temperature control through catalytic reaction during the operation of the fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 Schematic diagram of the structure of a fuel cell low-temperature thermal management system with an external catalytic reactor in an embodiment of the present invention.

[0026] Figure numerals: 1. fuel cell; 2. high-efficiency heat exchanger; 21. heat exchange coil; 3. anode gas supply channel; 4. cathode gas supply channel; 5. hydrogen-oxygen catalytic reactor; 6. high-temperature gas mixing channel; 7. hydrogen circuit; 8. first control valve; 9. second control valve; 10. gas-water separator. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0030] In the description of the embodiments of the present invention, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0031] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0032] Example

[0033] Reference Figure 1 , Figure 1 This is a schematic structural diagram of a fuel cell low-temperature thermal management system with an external catalytic reactor according to an embodiment of the present invention;

[0034] Specifically comprising: a fuel cell 1, an efficient heat exchanger 2 is provided at the air inlet end of the fuel cell 1, the positive electrode of the fuel cell 1 is connected to the anode gas supply channel 3, the negative electrode of the fuel cell 1 is connected to the cathode gas supply channel 4, and the anode gas supply channel 3 and the cathode gas supply channel 4 pass through the interior of the efficient heat exchanger 2;

[0035] A hydrogen-oxygen catalytic reactor 5 is provided at the gas outlet end of the fuel cell 1. The positive electrode and the negative electrode of the fuel cell 1 are connected to the hydrogen-oxygen catalytic reactor 5 through the anode gas outlet channel and the cathode gas outlet channel respectively. The hydrogen-oxygen catalytic reactor 5 is connected to the high-efficiency heat exchanger 2 through the high-temperature gas mixing channel 6.

[0036] A hydrogen circuit 7 is provided outside the positive electrode of the fuel cell 1. The two ends of the hydrogen circuit 7 are connected to the anode gas supply channel 3 and the anode gas outlet channel respectively. A first control valve 8 and a second control valve 9 are provided on the anode gas supply channel 3 and the anode gas outlet channel respectively. The first control valve 8 is provided between the hydrogen circuit 7 and the anode of the fuel cell 1, and the second control valve 9 is provided between the hydrogen circuit 7 and the hydrogen-oxygen catalytic reactor 5.

[0037] The present invention adopts a fuel cell 1, and a high-efficiency heat exchanger 2 is provided at the air inlet end of the fuel cell 1. The positive electrode of the fuel cell 1 is connected to the anode air supply channel 3, and the negative electrode of the fuel cell 1 is connected to the cathode air supply channel 4. The anode air supply channel 3 and the cathode air supply channel 4 pass through the interior of the high-efficiency heat exchanger 2; a hydrogen-oxygen catalytic reactor 5 is provided at the air outlet end of the fuel cell 1, and the positive electrode and the negative electrode of the fuel cell 1 are connected to the hydrogen-oxygen catalytic reactor 5 through the anode air outlet channel and the cathode air outlet channel respectively. The hydrogen-oxygen catalytic reactor 5 is connected to the high-efficiency heat exchanger 2 through a high-temperature gas mixing channel 6; a hydrogen circuit 7 is provided outside the positive electrode of the fuel cell 1, and the two ends of the hydrogen circuit 7 are connected to the anode air supply channel 3 and the anode air outlet channel respectively. A first control valve 8 and a second control valve 9 are provided on the anode air supply channel 3 and the anode air outlet channel respectively. The first control valve 8 is provided between the hydrogen circuit 7 and the anode of the fuel cell 1, and the second control valve 9 is provided between the hydrogen circuit 7 and the hydrogen-oxygen catalytic reactor 5. By means of the external hydrogen-oxygen catalytic reactor 5 and the high-efficiency heat exchanger 2, the exhaust gas of the fuel cell 1 is used for catalytic combustion to achieve thermal management in a low-temperature environment, thereby improving the energy efficiency of the system and achieving a cold start of the fuel cell 1 without the need for an externally powered electric heating system. At the same time, the design of the external hydrogen-oxygen catalytic reactor 5 and the third control valve enables temperature control to be achieved through the catalytic reaction during the operation of the fuel cell 1.

[0038] Next, the low-temperature thermal management system of the fuel cell with an external catalytic reactor in this exemplary embodiment will be further described.

[0039] In one embodiment of the present embodiment, a high-efficiency heat exchanger 2 is provided at the air inlet end of the above-mentioned fuel cell 1, the positive electrode of the above-mentioned fuel cell 1 is connected to the anode air supply channel 3, and hydrogen is introduced into the anode air supply channel 3, and the negative electrode of the above-mentioned fuel cell 1 is connected to the cathode air supply channel 4, and air is introduced into the cathode air supply channel 4. The above-mentioned anode air supply channel 3 and cathode air supply channel 4 pass through the interior of the high-efficiency heat exchanger 2, and the high-efficiency heat exchanger 2 can heat the hydrogen and air connected to the anode air supply channel 3 and inside the cathode air supply channel 4, thereby increasing the temperature of the fuel cell 1; a hydrogen-oxygen catalytic reactor 5 is provided at the air outlet end of the above-mentioned fuel cell 1, and the positive electrode and negative electrode of the above-mentioned fuel cell 1 are respectively connected to the hydrogen-oxygen catalytic reactor 5 through the anode air outlet channel and the cathode air outlet channel, and the above-mentioned hydrogen-oxygen catalytic reactor 5 is connected to the high-efficiency heat exchanger 2 through the high-temperature gas mixing channel 6; the hydrogen-oxygen catalytic reactor 5 is used to catalyze the combustion reaction of the introduced hydrogen and air to generate a high-temperature mixed gas, which is discharged into the interior of the high-efficiency heat exchanger 2 through the high-temperature gas mixing channel 6 to heat the inlet hydrogen and air.

[0040] In one embodiment, a heat exchange coil 21 is installed within the high-efficiency heat exchanger 2. The inlet end of the heat exchange coil 21 is connected to the outlet end of the high-temperature mixed gas channel 6. The outlet end of the heat exchange coil 21 extends to an external device via an external pipeline. The high-temperature mixed gas delivered from the hydrogen-oxygen catalytic reactor 5 enters the heat exchange coil 21 and flows within it, dissipating heat within the space within the high-efficiency heat exchanger 2. The hydrogen and air in the anode gas supply channel 3 and the cathode gas supply channel 4 are heated within the space within the high-efficiency heat exchanger 2. When the temperature reaches a predetermined value, the hydrogen and air enter the fuel cell 1 to react.

[0041] In one implementation of this embodiment, a hydrogen circuit 7 is provided outside the positive electrode of the fuel cell 1. The two ends of the hydrogen circuit 7 are respectively connected to the anode gas supply channel 3 and the anode gas outlet channel. The anode gas supply channel 3 and the anode gas outlet channel are respectively provided with a first control valve 8 and a second control valve 9. The first control valve 8 is provided between the hydrogen circuit 7 and the anode of the fuel cell 1, and the second control valve 9 is provided between the hydrogen circuit 7 and the hydrogen-oxygen catalytic reactor 5. The flow of hydrogen in the anode gas supply channel 3 and the anode gas outlet channel is controlled by controlling the opening and closing of the first control valve 8 and the second control valve 9.

[0042] In one embodiment, when the ambient temperature satisfies the fuel cell 1's operation, the first control valve 8 is controlled to open and the second control valve 9 is controlled to close. The hydrogen in the anode gas supply channel 3 normally enters the fuel cell 1, reacts with the air delivered to the fuel cell 1 from the cathode gas supply channel 4, and then enters the fuel cell 1 to achieve operation. At this time, the hydrogen flows through the fuel cell 1 and is recycled by the hydrogen circuit 7. When the ambient temperature and the inlet air and hydrogen temperatures are too low, the first control valve 8 is controlled to close and the second control valve 9 is controlled to open. The hydrogen in the anode gas supply channel 3 does not enter the fuel cell 1, but directly enters the hydrogen-oxygen catalytic reactor 5 via the hydrogen circuit 7, bypassing the fuel cell 1. Air also enters the catalytic reactor after passing through the fuel cell 1. The hydrogen and air undergo a catalytic reaction in the catalytic reactor, generating a high-temperature mixed gas. The high-temperature mixed gas then flows through the high-temperature mixed gas channel 6 and enters the high-efficiency heat exchanger 2 to heat the inlet hydrogen and air. When the fuel cell 1 reaches a certain temperature, the hydrogen flows through the fuel cell 1 again, and the fuel cell begins to start and self-heat, ultimately achieving a cold start of the fuel cell 1.

[0043] In one implementation of this embodiment, the hydrogen exhaust gas outlet of the positive terminal of the fuel cell 1 is connected to the hydrogen-oxygen catalytic reactor 5 through an exhaust gas pipeline, and a third control valve is provided at the hydrogen exhaust gas outlet.

[0044] In a specific embodiment, when the ambient temperature is too low during the operation of the fuel cell 1, the third control valve is controlled to open, and the anode hydrogen exhaust gas is discharged into the hydrogen-oxygen catalytic reactor 5 through the exhaust gas pipe, and catalytically reacts with the air at the negative electrode outlet of the fuel cell 1 to produce a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger 2 through the high-temperature mixed gas channel 6 to heat the hydrogen and air inside the anode gas supply channel 3 and the cathode gas supply channel 4.

[0045] As an example, the hydrogen circuit 7 is provided with two one-way valves in opposite directions. When the ambient temperature meets the requirements for the operation of the fuel cell 1, the one-way valve in the reverse direction (from the anode outlet of the fuel cell 1 to the anode inlet) on the hydrogen circuit 7 is opened, and the one-way valve in the forward direction is closed. After the hydrogen flows through the fuel cell 1, the hydrogen circuit 7 realizes the recycling of the hydrogen, thereby preventing part of the hydrogen from not entering the fuel cell 1 for reaction. When the ambient temperature and the inlet air and hydrogen temperatures are too low, the one-way valve in the reverse direction on the hydrogen circuit 7 is closed, and the one-way valve in the forward direction is opened. The hydrogen bypasses the fuel cell 1 and directly enters the hydrogen circuit 7, thereby preventing hydrogen from flowing back.

[0046] As an example, the first control valve 8, the second control valve 9, the third control valve and the one-way valve are respectively connected to an external controller, and the controller is connected to a temperature sensor, which is provided in the environment where the fuel cell 1 is located and is used to detect the ambient temperature.

[0047] In a specific embodiment, the ambient temperature is detected by a temperature sensor, and the detection signal is sent to the controller. The controller compares the detected temperature signal with a preset temperature value, generates a control instruction, and sends it to the first control valve 8, the second control valve 9, the third control valve and the one-way valve respectively.

[0048] In one implementation of this embodiment, a gas-water separator 10 is provided on the cathode outlet channel to separate liquid water, thereby preventing the liquid water from entering the hydrogen-oxygen catalytic reactor 5 and affecting the catalytic reaction.

[0049] In one implementation of this embodiment, rubber sealing rings are provided at the connection between the high-efficiency heat exchanger 2 and the anode gas supply channel 3 and the cathode gas supply channel 4, as well as at the connection between the hydrogen-oxygen catalytic reactor 5 and the high-temperature gas mixing channel 6. The rubber sealing rings prevent hydrogen or air from leaking out.

[0050] In one implementation of this embodiment, flow controllers are respectively provided at the gas inlet ends of the anode gas supply channel 3 and the cathode gas supply channel 4. The flow controllers can control the flow rates of hydrogen or air in the two gas supply channels.

[0051] The specific working process is as follows: when the ambient temperature reaches -10°C, which can meet the operation of the fuel cell 1, air and hydrogen enter the fuel cell 1 through the cathode and anode gas supply channels 3 to realize the operation of the battery. At this time, the hydrogen flows through the fuel cell 1 and is recycled by the hydrogen circuit 7; when the ambient temperature and the inlet air and hydrogen temperatures are lower than -10°C, hydrogen does not enter the fuel cell 1 during the cold start process of the fuel cell 1, and directly bypasses the fuel cell 1 through the hydrogen circuit 7 to enter the hydrogen-oxygen catalytic reactor 5. After flowing through the fuel cell 1, the air also enters the catalytic reactor. The hydrogen and air undergo a catalytic reaction in the catalytic reactor to produce a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger 2 through the high-temperature mixed gas channel 6 to heat the inlet Hydrogen and air. When the fuel cell 1 reaches a certain temperature, hydrogen flows through the fuel cell 1 again, and the battery starts to start and self-heat. At this time, the hydrogen exhaust gas at the battery outlet passes through the hydrogen-oxygen catalytic reactor 5. The high-temperature mixed gas after the reaction passes through the high-efficiency heat exchanger 2 to preheat the inlet working fluid to further increase the temperature of the battery, and finally achieve the cold start of the fuel cell 1; when the ambient temperature is lower than -10°C during the operation of the fuel cell 1, the anode hydrogen exhaust gas at the fuel cell 1 outlet will not be recycled through the hydrogen loop 7, but directly enter the hydrogen-oxygen catalytic reactor 5 to undergo catalytic reaction with the air at the cathode outlet of the fuel cell 1. The high-temperature mixed gas passes through the high-efficiency heat exchanger 2 to preheat the inlet working fluid, thereby achieving the purpose of maintaining the temperature of the fuel cell 1.

[0052] It should be noted that the fuel cell low-temperature thermal management system with an external catalytic reactor of the present invention is mainly used for air-cooled proton exchange membrane fuel cells, and can also be applied to liquid-cooled fuel cells. When it is applied to liquid-cooled fuel cells, the heat from the catalytic combustion of the exhaust gas can be used to preheat the inlet gas, or the coolant can be preheated, or the coolant and the inlet gas can be preheated at the same time. The outlet of the high-temperature mixing channel can be passed to different parts to preheat different working fluids according to actual needs.

[0053] In an embodiment of the present application, a low-temperature thermal management method for a fuel cell with an external catalytic reactor is also provided, which specifically includes the following steps:

[0054] Air and hydrogen are introduced into the cathode gas supply channel 4 and the anode gas supply channel 3 respectively, and the opening and closing of the first control valve 8, the second control valve 9 and the third control valve are controlled respectively according to the ambient temperature or the temperature value of the inlet air and hydrogen to realize the temperature control of the fuel cell 1.

[0055] Specifically, when the ambient temperature or the temperature of the inlet air or hydrogen reaches a preset temperature value, the first control valve 8 is controlled to open, the second control valve 9 is controlled to close, and the third control valve is controlled to close. Hydrogen enters the fuel cell 1 from the anode gas supply channel 3 for reaction and circulates through the hydrogen loop 7. Air enters the fuel cell 1 from the cathode gas supply channel 4 for reaction.

[0056] When the ambient temperature or the temperature of the inlet air or hydrogen is lower than a preset temperature value, the first control valve 8 is controlled to close, the second control valve 9 is controlled to open, and the third control valve is controlled to open. Hydrogen enters through the anode gas supply channel 3, passes through the hydrogen loop 7, and enters the hydrogen-oxygen catalytic reactor 5. Air flows through the cathode gas supply channel 4 and then enters the hydrogen-oxygen catalytic reactor 5 to undergo a catalytic reaction with the hydrogen, thereby generating a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger 2 through the high-temperature mixed gas channel 6, and heats the hydrogen and air inside the anode gas supply channel 3 and the cathode gas supply channel 4, thereby achieving a cold start of the fuel cell 1.

[0057] When the ambient temperature is too low during the operation of the fuel cell 1, the third control valve is controlled to open, and the anode hydrogen exhaust gas is discharged into the hydrogen-oxygen catalytic reactor 5 through the exhaust gas pipe, where it undergoes a catalytic reaction with the air at the negative electrode outlet of the fuel cell 1 to produce a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger 2 through the high-temperature mixed gas channel 6 to heat the hydrogen and air inside the anode gas supply channel 3 and the cathode gas supply channel 4, thereby achieving temperature control of the fuel cell 1.

[0058] It should be noted that the above preset temperature value is -10°C.

[0059] The beneficial effects of the embodiments of the present invention are as follows: except for the initial stage of cold start, the catalytic reaction uses the exhaust gas of the fuel cell 1 for catalytic combustion to achieve thermal management in a low-temperature environment, thereby improving the energy efficiency of the system; the system does not require an externally powered electric heating system, and the parasitic power is low; the external design of the catalytic reactor enables temperature control to be achieved through the catalytic reaction during the operation of the fuel cell 1.

[0060] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A low-temperature thermal management method for a fuel cell with an external catalytic reactor, characterized in that: The steps include: Air and hydrogen are introduced into the cathode gas supply channel and the anode gas supply channel respectively, and the opening and closing of the first control valve, the second control valve and the third control valve are controlled respectively according to the ambient temperature or the temperature of the inlet air and hydrogen to realize the temperature control of the fuel cell; The step of introducing air and hydrogen into the cathode gas supply channel and the anode gas supply channel, and controlling the opening and closing of the first control valve, the second control valve, and the third control valve according to the ambient temperature or the temperature of the inlet air and hydrogen, to achieve temperature control of the fuel cell includes: When the ambient temperature or the temperature of the inlet air or hydrogen reaches a preset temperature value, the first control valve is controlled to open, the second control valve is controlled to close, and the third control valve is controlled to close. Hydrogen enters the fuel cell through the anode gas supply channel for reaction and circulates through the hydrogen circuit. Air enters the fuel cell through the cathode gas supply channel for reaction. When the ambient temperature or the temperature of the inlet air or hydrogen is lower than the preset temperature value, the first control valve is controlled to close, the second control valve is controlled to open, and the third control valve is controlled to open, hydrogen enters through the anode gas supply channel, passes through the hydrogen loop and enters the hydrogen-oxygen catalytic reactor, and air flows through the cathode gas supply channel and then enters the hydrogen-oxygen catalytic reactor to undergo a catalytic reaction with the hydrogen, thereby generating a high-temperature mixed gas; the high-temperature mixed gas enters the high-efficiency heat exchanger through the high-temperature mixed gas channel to heat the hydrogen and air inside the anode gas supply channel and the cathode gas supply channel, thereby achieving a cold start of the fuel cell; When the ambient temperature is too low during the operation of the fuel cell, the third control valve is controlled to open, and the anode hydrogen exhaust gas is discharged into the hydrogen-oxygen catalytic reactor through the exhaust pipe, and catalytically reacts with the air at the negative electrode outlet of the fuel cell to generate a high-temperature mixed gas. The high-temperature mixed gas enters the high-efficiency heat exchanger through the high-temperature mixed gas channel to heat the hydrogen and air inside the anode gas supply channel and the cathode gas supply channel, thereby achieving temperature control of the fuel cell; The method is based on a fuel cell low-temperature thermal management system, which includes a fuel cell, an air inlet end of which is provided with a high-efficiency heat exchanger, the positive electrode of the fuel cell is connected to an anode gas supply channel, the negative electrode of the fuel cell is connected to a cathode gas supply channel, and the anode gas supply channel and the cathode gas supply channel pass through the interior of the high-efficiency heat exchanger; The fuel cell is provided with a hydrogen-oxygen catalytic reactor at the gas outlet end. The positive electrode and negative electrode of the fuel cell are connected to the hydrogen-oxygen catalytic reactor through the anode gas outlet channel and the cathode gas outlet channel respectively. The hydrogen-oxygen catalytic reactor is connected to the high-efficiency heat exchanger through the high-temperature gas mixing channel. A hydrogen circuit is provided outside the positive electrode of the fuel cell, and the two ends of the hydrogen circuit are respectively connected to the anode gas supply channel and the anode gas outlet channel. A first control valve and a second control valve are respectively provided on the anode gas supply channel and the anode gas outlet channel. The first control valve is provided between the hydrogen circuit and the anode of the fuel cell, and the second control valve is provided between the hydrogen circuit and the hydrogen-oxygen catalytic reactor.

2. The low-temperature thermal management method for a fuel cell with an external catalytic reactor according to claim 1, characterized in that: The preset temperature value is -10°C.

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