Compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system and method

Abstract

The invention provides a compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system, which is characterized in that a compressed air storage tank, an air heating pipeline and a humidifier are connected to form a heated air supply branch, and the heated air supply branch is communicated with an air inlet of an electric pile; the hydrogen storage bottle and the hydrogen heating pipeline are connected to form a heating hydrogen supply branch which is communicated with the hydrogen inlet of the electric pile; a cooling liquid outlet of the galvanic pile is communicated with the cooling liquid heat exchange pipeline, an outlet of the cooling liquid heat exchange pipeline is communicated with a cooling liquid inlet of the galvanic pile through a cooling liquid preheating branch, a cooling liquid circulating pump is arranged on the cooling liquid preheating branch, and the cooling liquid heat exchange pipeline exchanges heat with a heat storage medium; the heat storage device is used for storing waste heat of the pile cooling liquid in a heat storage medium or preheating the cooling liquid under the cold start working condition. Cathode air heating supply, anode hydrogen heating supply and galvanic pile preheating through cooling liquid under the cold start condition are achieved, and the advantages of being low in cold start energy consumption and fast in start response are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel cells, and in particular to a hydrogen fuel cell cold start system and method for storing energy by coupling compressed air with waste heat. Background Art

[0002] Driven by the global energy transition and the "dual carbon" goals, hydrogen transportation, as a zero-emission, high-energy-density sustainable transportation solution, is crucial for reducing carbon emissions in the transportation sector and alleviating dependence on fossil fuels. Hydrogen fuel cells convert hydrogen and oxygen into electricity through an electrochemical reaction, producing only water. Combining high efficiency and environmental friendliness, they are the core power technology for hydrogen transportation and are expected to achieve large-scale application in commercial vehicles, heavy trucks, rail transit, and other fields, driving a profound transformation of the transportation industry towards a low-carbon, clean future.

[0003] Hydrogen fuel cells face severe challenges in cold starts in low-temperature environments. When the ambient temperature drops below freezing, water inside the stack quickly condenses into ice, severely impacting the stack in terms of both performance loss and structural damage. Performance-wise, ice adheres to the surface of the proton exchange membrane, blocking the hydrogen ion conduction pathway. This significantly reduces the ion conduction efficiency of the proton exchange membrane and weakens the stack's power output. Simultaneously, the catalyst surface is covered in ice, preventing the active sites from fully contacting the reactants. The electrochemical reaction rate decreases significantly, making it difficult for the stack to generate electricity normally. Structurally, water expands by approximately 9% after freezing, exerting a strong squeezing force on the delicate internal structure of the stack, causing mechanical damage such as deformation of the bipolar plates and failure of seals. In extreme cases, it can even cause a short circuit, directly threatening the safe, stable operation and service life of the stack.

[0004] To solve this problem, traditional cold start technology adopts the strategy of "high-pressure purge + external heating". On the one hand, before the fuel cell stack is shut down, it relies on starting the air compressor to quickly establish a high-pressure air environment for the cathode, and uses the high-pressure airflow to purge the inside of the fuel cell stack to remove excess moisture; on the other hand, during the cold start process, solutions such as supplying gas to the cathode through the air compressor and using the waste heat of the air compressor to preheat the gas supply pipeline consume a lot of electricity; in addition, the use of high-power electric heating equipment (such as PTC heaters) to heat the coolant, air, hydrogen and the fuel cell stack body in all directions also requires high energy consumption. The applicant has found that the existing technology has at least the following technical problems: There are obvious deficiencies in this type of solution, which can be summarized as follows: the air compressor has high power consumption and seriously consumes vehicle energy; the high-power electric heater not only has high energy consumption itself, but also has significant thermal inertia in the heating process, resulting in a long system startup response time, which cannot meet the needs of hydrogen energy transportation and other fields for instant and rapid startup.

[0005] Therefore, the traditional cold start method has the shortcomings of high starting energy consumption and slow response. The development of low-energy consumption and fast-response cold start technology is the core direction to break through the bottleneck of low-temperature applications of hydrogen fuel cells. SUMMARY

[0006] The present application aims to provide a compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system and method to solve the technical problems of high energy consumption and slow response of the conventional cold start method in the prior art. The preferred technical solutions of the present application can produce a number of technical effects, which are described in detail below.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] The compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system provided by the present application comprises a compressed air storage tank, a heat storage type heat exchanger, a humidifier, and a hydrogen storage bottle, wherein:

[0009] The heat storage type heat exchanger comprises a shell, a cooling liquid heat exchange pipeline, an air heating pipeline, a hydrogen heating pipeline, and a heat storage medium located in the shell;

[0010] The compressed air storage tank, the air heating pipeline, and the humidifier are connected to form a heated air supply branch, and the heated air supply branch is connected to the air inlet of the stack;

[0011] The hydrogen storage bottle and the hydrogen heating pipeline are connected to form a heated hydrogen supply branch, and the heated hydrogen supply branch is connected to the hydrogen inlet of the stack;

[0012] The cooling liquid outlet of the stack is in a communication state with the cooling liquid heat exchange pipeline, the outlet of the cooling liquid heat exchange pipeline is connected to the cooling liquid inlet of the stack through a cooling liquid preheating branch, a cooling liquid circulating pump is arranged on the cooling liquid preheating branch, the cooling liquid heat exchange pipeline exchanges heat with the heat storage medium, and the heat storage medium is used to store the waste heat of the cooling liquid of the stack or preheat the cooling liquid under the cold start condition.

[0013] Preferably, the compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system further comprises an intercooler and an air cooler, wherein:

[0014] Another outlet of the cooling liquid heat exchange pipeline is connected to the intercooler, the air cooler, and the cooling liquid circulating pump to form a cooling liquid heat storage and heat dissipation branch, and the cooling liquid heat storage and heat dissipation branch is connected to the cooling liquid inlet of the stack.

[0015] Preferably, the compressed air and waste heat coupled energy storage hydrogen fuel cell cold start system further comprises an air compressor, a cathode main control valve, and an intercooler, wherein:

[0016] The air compressor, the intercooler and the humidifier are connected to form a cathode side air supply main line, which is communicated with an air inlet of the stack;

[0017] The air compressor and the intercooler are provided with a cathode main control valve for controlling whether the cathode side air supply main line is turned on.

[0018] Preferably, the air compressor and the compressed air storage tank are connected to form a compressed air storage energy branch, and the air compressor and the compressed air storage tank are provided with an air compressor outlet bypass valve for controlling whether the compressed air storage energy branch is turned on.

[0019] Preferably, the hydrogen storage bottle and the hydrogen inlet of the stack are communicated through a hydrogen supply main line;

[0020] The heating hydrogen supply branch is provided with a hydrogen supply branch inlet valve and a hydrogen supply branch outlet valve, and the hydrogen supply branch inlet valve and the hydrogen supply branch outlet valve are respectively located at an inlet pipe section and an outlet pipe section of the hydrogen heating pipe line.

[0021] The hydrogen supply main line is provided with an anode main control valve and a hydrogen storage bottle outlet valve in sequence along the hydrogen flow direction, and the inlet pipe section and the outlet pipe section of the hydrogen heating pipe line are respectively connected to an upstream section and a downstream section of the hydrogen storage bottle outlet valve.

[0022] Preferably, the cooling liquid heat exchange pipe line and the intercooler are provided with an intercooler inlet valve, and the air cooler and the cooling liquid circulating pump are provided with an air cooler outlet valve.

[0023] Preferably, the compressed air storage tank and the air heating pipe line are provided with a compressed air storage tank outlet valve for controlling whether the heating air supply branch is turned on.

[0024] The inlet pipe section of the cooling liquid heat exchange pipe line is provided with a cooling liquid inlet valve for controlling whether the cooling liquid outlet of the stack is communicated with the cooling liquid heat exchange pipe line.

[0025] The cooling liquid preheating branch is provided with a cooling liquid outlet valve for controlling whether the cooling liquid heat exchange pipe line is communicated with the cooling liquid inlet of the stack.

[0026] Preferably, the shell peripheral wall of the heat storage type heat exchanger is filled with heat insulation material, and the shell side wall of the heat storage type heat exchanger is fixed with an electric heat tracing assembly for heating the heat storage medium.

[0027] The present invention provides a hydrogen fuel cell cold start method using a compressed air and waste heat coupled energy storage system. The method comprises:

[0028] Under normal operation of the fuel cell stack: the coolant outlet of the fuel cell stack is connected to the coolant heat exchange pipeline, the coolant carries the heat of the fuel cell stack and exchanges heat with the heat storage medium in the coolant heat exchange pipeline, and the waste heat of the coolant is stored in the heat storage medium;

[0029] Under the cold start condition of the fuel cell stack:

[0030] On the cathode side, the air in the compressed air storage tank flows into the air heating pipeline to exchange heat with the heat storage medium, and the heated air is provided to the air inlet of the fuel cell stack through the heated air supply branch;

[0031] On the anode side, the hydrogen in the hydrogen storage bottle flows into the hydrogen heating pipeline to exchange heat with the heat storage medium, and the heated hydrogen is provided to the hydrogen inlet of the fuel cell stack through the heated hydrogen supply branch;

[0032] Under the action of the coolant circulation pump, the coolant flows into the coolant heat exchange pipeline to exchange heat with the heat storage medium. After the coolant is heated, it flows back to the coolant inlet of the fuel cell stack through the coolant preheating branch, thereby preheating the fuel cell stack.

[0033] Preferably, the hydrogen fuel cell cold start system for energy storage by coupling compressed air with waste heat further comprises an air compressor, the peripheral wall of the shell of the heat storage heat exchanger is filled with heat insulation material, and an electric heating component is fixed on the side wall of the shell of the heat storage heat exchanger;

[0034] The method further includes:

[0035] Under normal operating conditions of the fuel cell stack, the air compressor inputs compressed air into the compressed air storage tank, and the compressed air is stored in the compressed air storage tank;

[0036] When the fuel cell stack is shut down in an extremely low temperature environment for a long time, the electric heating component is used to heat the heat storage medium in the heat storage heat exchanger so that the temperature of the heat storage medium is maintained at a set temperature.

[0037] The hydrogen fuel cell cold start system and method for compressed air and waste heat coupled energy storage provided by the present invention have the following beneficial effects compared with the prior art:

[0038] Under normal operation condition of the stack, the waste heat of the cooling liquid is stored in the heat storage medium, under cold start condition of the stack, at the cathode side, the air in the compressed air storage tank is heated in the air heating pipeline and exchanges heat with the heat storage medium, and then flows into the air inlet of the stack after being heated; at the anode side, the hydrogen in the hydrogen storage bottle is heated in the hydrogen heating pipeline and exchanges heat with the heat storage medium, and then flows into the hydrogen inlet of the stack after being heated; under the action of the cooling liquid circulating pump, the cooling liquid flows into the cooling liquid heating pipeline and exchanges heat with the heat storage medium, and then realizes preheating of the stack after being heated. The system does not need to start the compressor, and does not need to use high-power and high-energy consumption electric heating equipment to heat the cooling liquid, air, hydrogen and the stack body, and fully utilizes the compressed air energy storage and the stack waste heat energy storage to realize cathode air heating supply, anode hydrogen heating supply and cooling liquid heating of the stack body under the cold start condition, has the advantages of low cold start energy consumption and fast start response, and breaks through the limitations of large power consumption of the air compressor, high energy consumption of the electric heating system and slow start response of the traditional cold start system. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, below the drawings needed to be used in the embodiments or prior art description will be briefly introduced, obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating labor.

[0040] Figure 1 It is a structure schematic diagram of a hydrogen fuel cell cold start system based on compressed air and waste heat coupling energy storage;

[0041] Figure 2 It is a structure schematic diagram of a heat storage type heat exchanger;

[0042] Figure 3 It is a structure schematic diagram of a cathode side air supply main road;

[0043] Figure 4 It is a structure schematic diagram of a compressed air energy storage branch;

[0044] Figure 5 It is a structure schematic diagram of a cathode side heating air supply under cold start condition

[0045] Figure 6 It is a structure schematic diagram of an anode side heating hydrogen supply under cold start condition;

[0046] Figure 7 It is a structure schematic diagram of a cooling liquid heat storage and heat dissipation branch and the stack;

[0047] Figure 8 It is a structure schematic diagram of a cooling liquid preheating branch and the stack under cold start condition.

[0048] In the figure, 1. air compressor; 2. compressed air storage tank; 3. heat storage heat exchanger; 4. intercooler; 5. air cooler; 6. coolant circulation pump; 7. humidifier; 8. battery pack; 9. hydrogen storage bottle; 10. air compressor outlet bypass valve; 11. cathode main control valve; 12. compressed air storage tank outlet valve; 13. anode main control valve; 14. hydrogen storage bottle outlet valve; 15. hydrogen supply branch inlet valve; 16. hydrogen supply branch outlet valve; 17. air cooler outlet valve; 18. coolant inlet valve; 19. coolant outlet valve; 20. intercooler inlet valve; 31. coolant heat exchange pipeline; 32. air heating pipeline; 33. hydrogen heating pipeline; 34. heat storage medium; 35. electric heating component; 36. thermal insulation material; 40. fuel cell stack. DETAILED DESCRIPTION

[0049] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0050] In the description of the present invention, it should be understood that the terms "center," "length," "width," "height," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," and "side" and the like, indicating positions or location relationships, are based on the positions or location relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0051] An embodiment of the present invention provides a hydrogen fuel cell cold start system and method that couples compressed air and waste heat to store energy. It does not require starting a compressor, nor does it require high-power, high-energy-consuming electric heating equipment to heat the coolant, air, hydrogen, and the fuel cell stack body. It fully utilizes compressed air energy storage, fuel cell waste heat storage, and low-power electric heating to simultaneously achieve cathode air heating supply, anode hydrogen heating supply, and coolant heating of the fuel cell stack body under cold start conditions, and has the advantages of low cold start energy consumption and fast start response.

[0052] The following combination Figures 1-8 The technical solution provided by the present invention is described in more detail.

[0053] Embodiment 1:

[0054] See also Figures 1-8As shown, the hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage provided by the present invention includes a compressed air storage tank 2, a heat storage heat exchanger 3, a humidifier 7, and a hydrogen storage bottle 9, wherein: the heat storage heat exchanger 3 includes a shell, a coolant heat exchange pipeline 31, an air heating pipeline 32, a hydrogen heating pipeline 33 and a heat storage medium 34 located in the shell; the compressed air storage tank 2, the air heating pipeline 32, and the humidifier 7 are connected to form a heated air supply branch, and the heated air supply branch is connected to the air inlet of the fuel cell stack 40; the hydrogen storage bottle 9. The hydrogen heating pipeline 33 is connected to form a heated hydrogen supply branch, which is connected to the hydrogen inlet of the fuel cell stack; the coolant outlet of the fuel cell stack is connected to the coolant heat exchange pipeline 31, and the outlet of the coolant heat exchange pipeline 31 is connected to the coolant inlet of the fuel cell stack through the coolant preheating branch. A coolant circulation pump 6 is provided on the coolant preheating branch. The coolant heat exchange pipeline 31 exchanges heat with the heat storage medium 34, which is used to store the waste heat of the fuel cell stack coolant in the heat storage medium 34, or to preheat the coolant under cold start conditions.

[0055] See also Figure 2 As shown, the air heating pipeline 32 and the hydrogen heating pipeline 33 are located on opposite sides of the shell of the thermal storage heat exchanger 3, and the coolant heat exchange pipeline 31 passes through the shell.

[0056] See also Figure 6 As shown, under normal operating conditions of the fuel cell stack: the coolant outlet of the fuel cell stack and the coolant heat exchange pipeline 31 are in a connected state, the coolant carries the heat of the fuel cell stack 40 and exchanges heat with the heat storage medium 34 in the coolant heat exchange pipeline 31, and the waste heat of the coolant is stored in the heat storage medium 34.

[0057] See also Figure 1 and Figure 5 As shown, a compressed air tank outlet valve 12 is provided between the compressed air tank 2 and the air heating pipeline 32 for controlling whether the heated air supply branch is open.

[0058] Under the cold start condition after the fuel cell stack is shut down, the compressed air stored in the compressed air tank 2 enters the air heating pipeline 32 in the heat storage heat exchanger 3 through the compressed air tank outlet valve 12, exchanges heat with the heat storage medium 34 on the outside of the pipe to heat it up, and then is sent to the humidifier 7 for humidification, and then supplies air to the cathode side of the fuel cell stack 40; this cold start process utilizes the compressed air in the compressed air tank 2 to supply air without starting the air compressor, thereby avoiding the cold start energy consumption generated by the air compressor in the traditional cold start process.

[0059] As an alternative embodiment, see Figure 1 、 Figure 6The hydrogen storage bottle 9 is connected to the hydrogen inlet of the fuel cell stack through the main hydrogen supply line; a hydrogen supply branch inlet valve 15 and a hydrogen supply branch outlet valve 16 are provided on the heating hydrogen supply branch line, and the hydrogen supply branch inlet valve 15 and the hydrogen supply branch outlet valve 16 are respectively located at the inlet pipe section and the outlet pipe section of the hydrogen heating pipeline 33; the anode main control valve 13 and the hydrogen storage bottle outlet valve 14 are sequentially provided along the hydrogen flow direction of the hydrogen supply main line, and the inlet pipe section and the outlet pipe section of the hydrogen heating pipeline 33 are respectively connected to the upstream section and the downstream section of the hydrogen storage bottle outlet valve 14.

[0060] Under cold start conditions after the fuel cell stack is shut down, the high-pressure hydrogen in the hydrogen storage bottle 9 enters the hydrogen heating pipeline 33 of the heat storage heat exchanger 3 through the anode main control valve 13 and the hydrogen supply branch inlet valve 15, exchanges heat with the heat storage medium 34 outside the pipe to heat it up, and then is input into the anode side of the fuel cell stack 40.

[0061] See also Figure 8 The inlet pipe section of the coolant heat exchange pipeline 31 is provided with a coolant inlet valve 18, which is used to control whether the coolant outlet of the fuel cell stack is connected to the coolant heat exchange pipeline 31; a coolant outlet valve 19 is provided on the coolant preheating branch to control whether the coolant heat exchange pipeline 31 is connected to the coolant inlet of the fuel cell stack.

[0062] See also Figure 1 、 Figure 8 The coolant circulation pump 6, the coolant inlet valve 18, the coolant heat exchange pipeline 31, and the coolant outlet valve 19 constitute a coolant preheating branch; under the cold start condition, the coolant is driven by the coolant circulation pump 6 to flow through the coolant inlet valve 18, the heat storage heat exchanger 3, and the coolant outlet valve 19; in the heat storage heat exchanger 3, after absorbing the heat stored in the heat storage medium 34 through the coolant heat exchange pipeline 31 and exchanging heat with the heat storage medium 34, the coolant heats up and transfers the heat to the fuel cell stack to preheat the fuel cell stack.

[0063] See also Figure 1-Figure 7 As shown, under the cold start condition of the fuel cell stack, the coolant heat exchange pipeline 31, the air heating pipeline 32, and the hydrogen heating pipeline 33 can all exchange heat with the heat storage medium 34 to heat the fuel cell stack, the air entering the fuel cell stack, and the hydrogen entering the fuel cell stack, respectively, thereby achieving low-energy consumption and rapid cold start of the fuel cell stack without starting the air compressor or requiring high-power electric and high-energy consumption heating devices.

[0064] As an alternative embodiment, see Figure 1 As shown, the hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage also includes an intercooler 4 and an air cooler 5, wherein: the other outlet of the coolant heat exchange pipeline 31 is connected to the intercooler 4, the air cooler 5, and the coolant circulation pump 6 to form a coolant heat storage and heat dissipation branch, and the coolant heat storage and heat dissipation branch is connected to the coolant inlet of the fuel cell stack.

[0065] See also Figure 1 and Figure 6 As shown, an intercooler inlet valve 20 is provided on the pipeline between the coolant heat exchange pipeline 31 and the intercooler 4 , and an air cooler outlet valve 17 is provided on the pipeline between the air cooler 5 and the coolant circulation pump 6 .

[0066] Under normal operation of the stack: the coolant outlet of the stack is connected to the coolant heat exchange pipe 31, and the coolant carries the heat of the stack and exchanges heat with the heat storage medium 34 in the coolant heat exchange pipe 31, storing the waste heat of the coolant in the heat storage medium 34. In this process, see Figure 1 and Figure 6 As shown, during normal operation of the stack, coolant circulation and heat storage and heat dissipation, coolant circulation pump 6 drives the coolant to absorb heat generated by the electrochemical reaction within the stack. This heat is then exchanged with heat storage medium 34 outside the heat storage heat exchanger 3 in coolant heat exchange pipe 31, releasing and storing the heat in heat storage medium 34. The coolant then flows sequentially through intercooler inlet valve 20, intercooler 4, air cooler 5, and air cooler outlet valve 17, completing the coolant heat storage and heat dissipation cycle before returning to the stack. This process involves no coolant loss.

[0067] As an alternative embodiment, see Figure 1 and Figure 3 As shown, the hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage also includes an air compressor 1, a cathode main control valve 11, and an intercooler 4. The air compressor 1, intercooler 4, and humidifier 7 are connected to form a cathode side air supply main path, which is connected to the air inlet of the fuel cell stack. A cathode main control valve 11 is provided between the air compressor 1 and the intercooler 4 to control whether the cathode side air supply main path is open. Figure 1 and Figure 4 As shown, the air compressor 1 is connected to the compressed air storage tank 2 to form a compressed air energy storage branch, and an air compressor outlet bypass valve 10 is provided between the air compressor 1 and the compressed air storage tank 2 for controlling whether the compressed air energy storage branch is conductive.

[0068] like Figure 3 As shown, the air compressor 1, the cathode main control valve 11, and the intercooler 4 constitute the main air supply path on the cathode side; the air compressor 1, the air compressor outlet bypass valve 10, and the compressed air storage tank 2 constitute the compressed air energy storage branch; under normal operating conditions of the fuel cell stack, the air compressor 1 inputs and stores compressed air into the compressed air storage tank 2 through the air compressor outlet bypass valve 10.

[0069] As an optional embodiment, the shell peripheral wall of the thermal storage heat exchanger 3 is filled with thermal insulation material 36, and the shell side wall of the thermal storage heat exchanger 3 is fixed with an electric heating component 35 for heating the heat storage medium.

[0070] Driven by the battery pack 8, the electric heating component 35 performs low-power heating and temperature maintenance on the outer surface of the heat storage heat exchanger 3, supplementing the heat loss of the heat storage medium 34 to the environment through the outer surface of the heat storage heat exchanger 3. The thermal insulation material 36 is used to insulate the heat storage heat exchanger to reduce the heat loss of the heat storage heat exchanger 3 to the surrounding environment through its outer surface. This combination of waste heat storage, low-power heating and temperature maintenance, and thermal insulation avoids the power consumption of high-power heating of the coolant and the fuel cell body under traditional cold start conditions, and has the advantages of low heating power and low cold start energy consumption.

[0071] Example 2:

[0072] See also Figures 1-8 As shown, this embodiment provides a hydrogen fuel cell cold start method with compressed air and waste heat coupled energy storage, using the hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage of Example 1, the method includes: under normal operating conditions of the fuel cell stack: making the coolant outlet of the fuel cell stack and the coolant heat exchange pipeline 31 connected, the coolant carries the heat of the fuel cell stack and exchanges heat with the heat storage medium 34 in the coolant heat exchange pipeline 31, and stores the waste heat of the coolant in the heat storage medium 34.

[0073] Under the cold start condition of the fuel cell stack: on the cathode side, the air in the compressed air storage tank 2 flows into the air heating pipeline 32 to exchange heat with the heat storage medium 34, and the heated air is provided to the air inlet of the fuel cell stack through the heated air supply branch; on the anode side, the hydrogen in the hydrogen storage bottle 9 flows into the hydrogen heating pipeline 33 to exchange heat with the heat storage medium 34, and the heated hydrogen is provided to the hydrogen inlet of the fuel cell stack through the heated hydrogen supply branch; under the action of the coolant circulation pump 6, the coolant flows into the coolant heat exchange pipeline 31 to exchange heat with the heat storage medium 34, and after the coolant is heated, it flows back to the coolant inlet of the fuel cell stack through the coolant preheating branch, thereby preheating and heating the fuel cell stack.

[0074] Specifically, this embodiment provides a hydrogen fuel cell cold start method for compressed air and waste heat coupled energy storage. First, under normal operating conditions of the fuel cell stack, Figure 4 The compressed air energy storage branch shown in the figure stores compressed air in the compressed air storage tank 2. Figure 7 The coolant heat storage and heat dissipation branch shown stores the heat generated inside the fuel cell stack carried out by the coolant in the heat storage heat exchanger 3 .

[0075] Secondly, under the cold start condition of the stack, Figure 5 、 Figure 6 and Figure 8 The heating air supply branch, heating hydrogen supply branch, and coolant preheating branch shown in the figure heat the cathode side air, anode side hydrogen, coolant, and fuel cell stack at the same time; when the fuel cell stack is shut down in an extremely low temperature environment for a long time, the following Figure 2 The low-power electric heat tracing assembly 35 shown heats and maintains the temperature of the heat storage heat exchanger 3, so that the low-energy and rapid cold start of the electric pile can be realized without starting the air compressor and without high-power electric heating devices with high energy consumption.

[0076] The specific steps include: first, on the cathode gas supply side of the electric pile, a compressed air energy storage bypass is arranged at the outlet of the air compressor 1, the compressed air storage tank outlet valve is kept closed, the air compressor outlet bypass valve 10 is opened, high-pressure air is input into and stored in the compressed air storage tank 2; at the same time, under the driving of the cooling liquid circulating pump 6, the cooling liquid enters the cooling liquid heat exchange pipeline 31 in the heat storage heat exchanger through the cooling liquid inlet valve 18 after absorbing heat in the electric pile, exchanges heat with the heat storage medium 34 and stores heat in the heat storage heat exchanger 3, and then sequentially flows through the intercooler inlet valve 20, the intercooler 4, the air cooler 5 and the air cooler outlet valve 17 to complete the cooling liquid heat storage and heat dissipation cycle.

[0077] Secondly, in the low-temperature cold start condition after the electric pile is stopped, the air compressor outlet bypass valve 10, the cathode main control valve 11, the intercooler inlet valve 20, the air cooler outlet valve 17 and the hydrogen storage bottle outlet valve 14 are kept closed, the compressed air storage tank outlet valve 12, the cooling liquid storage inlet valve 18, the cooling liquid outlet valve 19, the hydrogen supply branch inlet valve 15 and the hydrogen supply branch outlet valve 16 are opened; on the cathode side, the high-pressure air in the compressed air storage tank 2 enters the air heating pipeline 32 in the heat storage heat exchanger through the compressed air storage tank outlet valve 12, exchanges heat with the heat storage medium 34, enters the humidifier 7 after being heated and humidified, and supplies hot air to the cathode of the electric pile; on the anode side, the hydrogen in the hydrogen storage bottle 9 enters the hydrogen heating pipeline 33 in the heat storage heat exchanger through the anode main control valve 13 and the hydrogen supply branch inlet valve 15, exchanges heat with the heat storage medium 34, is heated and humidified, and supplies hot hydrogen to the anode of the electric pile; on the cooling liquid preheating branch, under the driving of the cooling liquid circulating pump 6, the cooling liquid enters the cooling liquid heat exchange pipeline 31 in the heat storage heat exchanger through the cooling liquid inlet valve 18, exchanges heat with the heat storage medium 34, is heated and humidified, and then enters the electric pile body through the cooling liquid outlet valve 19 to preheat and heat the electric pile.

[0078] The hydrogen fuel cell cold start method based on compressed air and waste heat coupled energy storage has the advantages of low cold start energy consumption and fast start response, breaks through the limitations of large air compressor power consumption, high electric heating system energy consumption and slow system start response of the traditional cold start system, and has a wide application prospect in the field of low-energy and rapid cold start of hydrogen fuel cells.

[0079] In the description of the present specification, a specific feature, structure, or characteristic can be combined in an appropriate manner in any one or more embodiments or examples.

[0080] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. The illustrative expressions of the above terms in the present specification do not necessarily refer to the same embodiment or example. Also, the specific feature, structure, material, or characteristic described can be combined in an appropriate manner in any one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples, without contradiction.

[0081] The above merely describes the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A hydrogen fuel cell cold start system that stores energy by coupling compressed air with waste heat, characterized in that: The invention comprises a compressed air storage tank (2), a heat storage heat exchanger (3), a humidifier (7), and a hydrogen storage bottle (9), wherein: The heat storage heat exchanger (3) comprises a shell, a coolant heat exchange pipeline (31) located in the shell, an air heating pipeline (32), a hydrogen heating pipeline (33), and a heat storage medium (34); The compressed air storage tank (2), the air heating pipeline (32), and the humidifier (7) are connected to form a heated air supply branch, and the heated air supply branch is connected to the air inlet of the fuel cell stack; The hydrogen storage bottle (9) and the hydrogen heating pipeline (33) are connected to form a heated hydrogen supply branch, and the heated hydrogen supply branch is connected to the hydrogen inlet of the fuel cell stack; The coolant outlet of the stack is in communication with the coolant heat exchange pipeline (31), the outlet of the coolant heat exchange pipeline (31) is in communication with the coolant inlet of the stack via a coolant preheating branch, a coolant circulation pump (6) is provided on the coolant preheating branch, the coolant heat exchange pipeline (31) exchanges heat with the heat storage medium (34), and is used to store waste heat of the stack coolant in the heat storage medium (34), or to preheat the coolant under cold start conditions.

2. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 1 is characterized in that: The hydrogen fuel cell cold start system for energy storage by coupling compressed air with waste heat further comprises an intercooler (4) and an air cooler (5), wherein: The other outlet of the coolant heat exchange pipeline (31) is connected to the intercooler (4), the air cooler (5), and the coolant circulation pump (6) to form a coolant heat storage and heat dissipation branch, and the coolant heat storage and heat dissipation branch is connected to the coolant inlet of the fuel cell stack.

3. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 1 is characterized in that: The hydrogen fuel cell cold start system for compressed air and waste heat coupled energy storage further comprises an air compressor (1), a cathode main control valve (11), and an intercooler (4), wherein: The air compressor (1), the intercooler (4), and the humidifier (7) are connected to form a cathode side air supply main path, and the cathode side air supply main path is connected to the air inlet of the fuel cell stack; A cathode main control valve (11) is provided between the air compressor (1) and the intercooler (4), and the cathode main control valve (11) is used to control whether the cathode side air supply main path is open.

4. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 3 is characterized in that: The air compressor (1) and the compressed air storage tank (2) are connected to form a compressed air energy storage branch, and an air compressor outlet bypass valve (10) is provided between the air compressor (1) and the compressed air storage tank (2) for controlling whether the compressed air energy storage branch is conductive.

5. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 1 is characterized in that: The hydrogen storage bottle (9) is connected to the hydrogen inlet of the fuel cell stack via a main hydrogen supply path; The heating hydrogen supply branch is provided with a hydrogen supply branch inlet valve (15) and a hydrogen supply branch outlet valve (16), and the hydrogen supply branch inlet valve (15) and the hydrogen supply branch outlet valve (16) are respectively located at the inlet pipe section and the outlet pipe section of the hydrogen heating pipeline (33); An anode main control valve (13) and a hydrogen storage bottle outlet valve (14) are sequentially arranged on the hydrogen supply main line along the hydrogen flow direction, and the inlet pipe section and the outlet pipe section of the hydrogen heating pipeline (33) are respectively connected to the upstream section and the downstream section of the hydrogen storage bottle outlet valve (14).

6. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 2 is characterized in that: An intercooler inlet valve (20) is provided on the pipeline between the coolant heat exchange pipeline (31) and the intercooler (4), and an air cooler outlet valve (17) is provided on the pipeline between the air cooler (5) and the coolant circulation pump (6).

7. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 1 is characterized in that: A compressed air tank outlet valve (12) is provided between the compressed air tank (2) and the air heating pipeline (32) for controlling whether the heated air supply branch is open; The inlet pipe section of the coolant heat exchange pipeline (31) is provided with a coolant inlet valve (18) for controlling whether the coolant outlet of the stack is in communication with the coolant heat exchange pipeline (31); A coolant outlet valve (19) is provided on the coolant preheating branch circuit, for controlling whether the coolant heat exchange pipeline (31) is connected to the coolant inlet of the fuel cell stack.

8. The hydrogen fuel cell cold start system with compressed air and waste heat coupled energy storage according to claim 1 is characterized in that: The peripheral wall of the shell of the heat storage heat exchanger (3) is filled with heat insulation material (36), and the side wall of the shell of the heat storage heat exchanger (3) is fixed with an electric heating component (35) for heating the heat storage medium.

9. A hydrogen fuel cell cold start method using compressed air and waste heat coupled energy storage, characterized in that: Using the hydrogen fuel cell cold start system for compressed air and waste heat coupled energy storage according to any one of claims 1 to 8, the method comprises: Under normal operation of the stack: the coolant outlet of the stack is connected to the coolant heat exchange pipeline (31), the coolant carries the heat of the stack and exchanges heat with the heat storage medium (34) in the coolant heat exchange pipeline (31), and the waste heat of the coolant is stored in the heat storage medium (34); Under the cold start condition of the fuel cell stack: On the cathode side, the air in the compressed air storage tank (2) flows into the air heating pipeline (32) to exchange heat with the heat storage medium (34), and the heated air is provided to the air inlet of the fuel cell stack through the heated air supply branch; On the anode side, the hydrogen in the hydrogen storage bottle (9) flows into the hydrogen heating pipeline (33) to exchange heat with the heat storage medium (34), and the heated hydrogen is provided to the hydrogen inlet of the fuel cell stack through the heated hydrogen supply branch; Under the action of the coolant circulation pump (6), the coolant flows into the coolant heat exchange pipeline (31) to exchange heat with the heat storage medium (34). After the coolant is heated, it flows back to the coolant inlet of the battery stack through the coolant preheating branch, thereby achieving preheating and heating of the battery stack.

10. The hydrogen fuel cell cold start method with compressed air and waste heat coupled energy storage according to claim 9, characterized in that: The hydrogen fuel cell cold start system for energy storage by coupling compressed air with waste heat also includes an air compressor (1), a shell peripheral wall of the heat storage heat exchanger (3) is filled with a heat insulation material (36), and an electric heating component (35) is fixed on the shell side wall of the heat storage heat exchanger (3); The method further includes: Under normal operating conditions of the fuel cell stack, the air compressor inputs compressed air into the compressed air storage tank (2), and the compressed air is stored in the compressed air storage tank (2); When the battery stack is shut down in an extremely low temperature environment for a long time, the electric heating component (35) is used to heat the heat storage medium (34) in the heat storage heat exchanger (3) so that the temperature of the heat storage medium (34) is maintained at a set temperature.

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