Air heating device, fuel cell, and vehicle

Abstract

The application provides an air heating device, a fuel cell and a vehicle. The air heating device comprises an air compressor, a secondary intercooler, a humidifier and a stack. The air outlet of the stack is communicated with the first air inlet of the secondary intercooler, the first air outlet of the secondary intercooler is communicated with the wet inlet of the humidifier, the outlet of the air compressor is communicated with the second air inlet of the secondary intercooler, the second air outlet of the secondary intercooler is communicated with the air inlet of the humidifier, and the outlet of the humidifier is communicated with the air inlet of the stack. The problem that the humidity of the outlet of the humidifier is low and the humidity of the inlet of the stack is limited is solved.

Description

Technical Field

[0001] This invention belongs to the field of new energy technology, and in particular relates to an air heating device, a fuel cell, and a vehicle. Background Technology

[0002] A fuel cell is a device that converts the chemical energy of hydrogen and oxygen into electrical energy. Hydrogen fuel cells are very demanding in terms of their operating environment; suitable temperature, humidity, and pressure are all crucial to their performance. The humidifier in the air subsystem of existing fuel cell systems uses the water generated during the reaction to humidify the inlet air, providing the fuel cell with a suitable reaction environment.

[0003] Currently, all humidifiers work on the principle of convection and diffusion. Moisture and dry air flow in opposite directions, and there is a permeable membrane or porous structure between the moisture and dry air. Water molecules and small water droplets in the moisture can permeate and diffuse into the dry air, thereby achieving the effect of humidifying dry air with moisture.

[0004] The existing technology has the following drawbacks:

[0005] 1. Humidifiers rely on the concentration difference of water molecules for diffusion. When the humidity at the outlet of the humidifier is low, it will limit the humidity at the inlet of the fuel cell stack.

[0006] 2. It's not just water molecules that diffuse between the dry and wet sides of the humidifier; the different concentrations of nitrogen and oxygen also diffuse between the dry and wet chambers. When the nitrogen concentration at the fuel cell stack outlet is high, it diffuses towards the inlet, increasing the nitrogen concentration at the stack's air inlet and consequently decreasing the oxygen concentration, further reducing the fuel cell's power generation performance. Summary of the Invention

[0007] In view of the problems existing in the prior art, the present invention provides an air heating device, a fuel cell and a vehicle, which at least partially solves the problem that the low humidity at the humidifier outlet limits the humidity at the fuel cell inlet.

[0008] In a first aspect, embodiments of this disclosure provide an air heating device, including: an air compressor, a secondary intercooler, a humidifier, and an electric stack;

[0009] The air outlet of the fuel cell stack is connected to the first air inlet of the auxiliary intercooler, the first air outlet of the auxiliary intercooler is connected to the wet inlet of the humidifier, the outlet of the air compressor is connected to the second air inlet of the auxiliary intercooler, the second air outlet of the auxiliary intercooler is connected to the air inlet of the humidifier, and the outlet of the humidifier is connected to the air inlet of the fuel cell stack.

[0010] Optionally, it also includes a main intercooler, which is disposed between the second air outlet of the auxiliary intercooler and the air inlet of the humidifier. The inlet of the main intercooler is connected to the second air outlet of the auxiliary intercooler, and the outlet of the main intercooler is connected to the air inlet of the humidifier.

[0011] Optionally, a three-way valve is provided between the air compressor and the auxiliary intercooler.

[0012] Optionally, one outlet of the three-way valve is connected to the second air inlet of the auxiliary intercooler, and the other outlet of the three-way valve is connected to the tailpipe.

[0013] Optionally, a throttle valve is installed on the pipe connecting the exhaust port of the humidifier to the tailpipe.

[0014] Optionally, a tailpipe manifold is provided on the tailpipe, and the exhaust port of the humidifier is connected to the tailpipe manifold.

[0015] Optionally, a flow meter is installed at the inlet of the air blower, and the outlet of the flow meter is connected to the outlet of the air blower.

[0016] Optionally, the high-temperature air generated by the air compressor heats the fuel cell outlet air through the auxiliary intercooler, and the fuel cell outlet air exchanges heat with the high-temperature air output by the air compressor.

[0017] The high-temperature air output by the air compressor is cooled by the main intercooler to obtain cooled air. The cooled air is input into the air inlet of the humidifier. The cooled air is obtained by reducing the high-temperature air output by the air compressor to meet the set temperature of the fuel cell inlet.

[0018] The heated fuel cell outlet air is fed into the wet inlet of the humidifier. The heated fuel cell outlet air humidifies the cooled air in the humidifier and then the humidified cooled air is fed into the fuel cell.

[0019] Secondly, embodiments of this disclosure also provide a fuel cell, including any of the air heating devices described in the first aspect.

[0020] Thirdly, embodiments of this disclosure also provide a vehicle including any of the air heating devices described in the first aspect.

[0021] This invention provides an air heating device, a fuel cell, and a vehicle. The air heating device heats the outlet air of the fuel cell stack using waste heat generated by an air compressor. Since the outlet air has a sufficient liquid water content, heating it raises the dew point and increases the water molecule concentration. This facilitates the diffusion of water molecules within the humidifier towards the fuel cell stack inlet air path, further raising the dew point of the inlet air and thus solving the problem of low humidity at the humidifier outlet limiting humidity at the fuel cell stack inlet.

[0022] By heating the air at the fuel cell stack outlet, the concentration of water molecules in the humidifier is increased, further diluting the nitrogen gas and reducing the diffusion of nitrogen gas from the humidifier to the fuel cell stack inlet. Attached Figure Description

[0023] The above and other objects, features and advantages of this disclosure will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.

[0024] Figure 1 This is a schematic diagram of the structure of an air heating device provided in an embodiment of the present disclosure;

[0025] in:

[0026] 1-Flow meter; 2-Air compressor; 3-Three-way valve; 4-Auxiliary intercooler; 401-First air inlet; 402-First air outlet; 403-Second air inlet; 404-Second air outlet; 5-Fuel cell stack; 501-Air inlet of fuel cell stack; 502-Air outlet of fuel cell stack; 6-Humidifier; 601-Outlet of humidifier; 602-Wet inlet of humidifier; 603-Air inlet of humidifier; 604-Exhaust port of humidifier; 7-Main intercooler; 8-Throttle valve; 9-Exhaust manifold. Detailed Implementation

[0027] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0028] It should be understood that the following specific examples illustrate the implementation of this disclosure, and those skilled in the art can easily understand other advantages and effects of this disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. This disclosure can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0029] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0030] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this disclosure. The illustrations only show the components related to this disclosure and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0031] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0032] like Figure 1 As shown, this embodiment discloses an air heating device, including: an air compressor, a secondary intercooler, a humidifier, and an electric stack;

[0033] The air outlet of the fuel cell stack is connected to the first air inlet of the auxiliary intercooler, the first air outlet of the auxiliary intercooler is connected to the wet inlet of the humidifier, the outlet of the air compressor is connected to the second air inlet of the auxiliary intercooler, the second air outlet of the auxiliary intercooler is connected to the air inlet of the humidifier, and the outlet of the humidifier is connected to the air inlet of the fuel cell stack.

[0034] Optionally, it also includes a main intercooler, which is disposed between the second air outlet of the auxiliary intercooler and the air inlet of the humidifier. The inlet of the main intercooler is connected to the second air outlet of the auxiliary intercooler, and the outlet of the main intercooler is connected to the air inlet of the humidifier.

[0035] Optionally, a three-way valve is provided between the air compressor and the auxiliary intercooler.

[0036] Optionally, one outlet of the three-way valve is connected to the second air inlet of the auxiliary intercooler, and the other outlet of the three-way valve is connected to the tailpipe.

[0037] Optionally, a throttle valve is installed on the pipe connecting the exhaust port of the humidifier to the tailpipe.

[0038] Optionally, a tailpipe manifold is provided on the tailpipe, and the exhaust port of the humidifier is connected to the tailpipe manifold.

[0039] Optionally, a flow meter is installed at the inlet of the air blower, and the outlet of the flow meter is connected to the outlet of the air blower.

[0040] Optionally, the high-temperature air generated by the air compressor heats the fuel cell outlet air through the auxiliary intercooler, and the fuel cell outlet air exchanges heat with the high-temperature air output by the air compressor.

[0041] The high-temperature air output by the air compressor is cooled by the main intercooler to obtain cooled air. The cooled air is input into the air inlet of the humidifier. The cooled air is obtained by reducing the high-temperature air output by the air compressor to meet the set temperature of the fuel cell inlet.

[0042] The heated fuel cell outlet air is fed into the wet inlet of the humidifier. The heated fuel cell outlet air humidifies the cooled air in the humidifier and then the humidified cooled air is fed into the fuel cell.

[0043] The air outlet of the fuel cell stack is connected to the auxiliary intercooler at the rear end of the three-way valve. After being heated by the auxiliary intercooler, the air is then connected to the wet inlet of the humidifier.

[0044] Due to the work done by the air compressor, the air temperature at the compressor's downstream end is very high. This high temperature is unacceptable to the fuel cell stack. Therefore, in existing technology, this heat is dissipated to the outside via the intercooler and radiator, resulting in energy waste. In this embodiment, this heat is used to heat the fuel cell stack outlet air. After passing through the auxiliary intercooler, the inlet air's temperature is approximately 90°C, requiring further heat dissipation.

[0045] The main intercooler is responsible for continuing to cool the inlet air coming out of the auxiliary intercooler until the temperature of the fuel cell inlet air is within a suitable range.

[0046] Because the liquid water content at the fuel cell stack outlet is sufficient, heating the outlet air can raise its dew point and increase the water molecule concentration. This facilitates the diffusion of water molecules within the humidifier towards the fuel cell stack inlet air path, thus raising the dew point of the inlet air as well. Increasing the humidity at the fuel cell stack inlet contributes to the increase in individual cell voltage. For every 1mV increase, in a dual-stack fuel cell system with 700 individual cells, the total voltage increases by 700mV, and the rated power of the stack increases by 500W. Based on empirical data, a 5% increase in air humidity results in a 5mV increase in individual cell voltage and an approximately 2 to 3kW increase in rated power, demonstrating a significant effect.

[0047] As oxygen in the air is consumed within the fuel cell stack, the oxygen concentration decreases, and the nitrogen concentration increases accordingly. This causes nitrogen from the outlet air to diffuse into the inlet air within the humidifier, reducing the oxygen concentration at the fuel cell stack inlet. (Especially at low power points, when less moisture is generated and the fuel cell stack is drier.) The device in this embodiment increases the water molecule concentration, further diluting the nitrogen and reducing the diffusion of nitrogen from the humidifier into the fuel cell stack inlet.

[0048] This embodiment has the following effects:

[0049] 1. By utilizing the waste heat generated by the air compressor to heat the outlet air, a simple structural change leads to higher efficiency. This structure increases the overall voltage of the fuel cell stack, thereby improving the net power output of the fuel cell system and enhancing its economics.

[0050] Second, if the fuel cell system uses an expander, the heat from heating the outlet air can be absorbed by the expander and used as power for the air inlet, thus increasing the working efficiency of the expander.

[0051] Third, due to the nitrogen diffusion effect in the humidifier, the oxygen concentration of the inlet air will be slightly reduced. This will result in the air compressor needing to provide more airflow to achieve the same power output from the fuel cell stack. Therefore, reducing nitrogen diffusion within the humidifier indirectly reduces the power consumption of the air compressor and improves system efficiency.

[0052] This embodiment also discloses a fuel cell, including the air heating device of this embodiment.

[0053] In addition, this embodiment also discloses a vehicle, including the air heating device of this embodiment.

[0054] The basic principles of this disclosure have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.

[0055] In this disclosure, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The block diagrams of devices, apparatuses, devices, and systems involved in this disclosure are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as "comprising," "including," "having," etc., are open-ended terms meaning "including but not limited to," and are used interchangeably with them. The terms "or" and "and" as used herein refer to the terms "and / or," and are used interchangeably with them unless the context clearly indicates otherwise. The term "such as" as used herein refers to the phrase "such as but not limited to," and is used interchangeably with it.

[0056] Additionally, as used herein, the "or" used in a list of items beginning with "at least one" indicates a separate list, such that a list of, for example, "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not imply that the described example is preferred or better than other examples.

[0057] It should also be noted that in the systems and methods of this disclosure, the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions to this disclosure.

[0058] Various changes, substitutions, and modifications can be made to the technology described herein without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of this disclosure is not limited to the specific aspects of the processes, machines, manufactures, events, means, methods, and actions described above. Currently existing or later-developed processes, machines, manufactures, events, means, methods, or actions that perform substantially the same function or achieve substantially the same result as the corresponding aspects described herein can be utilized. Therefore, the appended claims include such processes, machines, manufactures, events, means, methods, or actions within their scope.

[0059] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0060] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.

Claims

1. An air heating device, characterized in that, include: Air compressor, auxiliary intercooler, humidifier and fuel cell stack; The air outlet of the fuel cell stack is connected to the first air inlet of the auxiliary intercooler, the first air outlet of the auxiliary intercooler is connected to the wet inlet of the humidifier, the outlet of the air compressor is connected to the second air inlet of the auxiliary intercooler, the second air outlet of the auxiliary intercooler is connected to the air inlet of the humidifier, and the outlet of the humidifier is connected to the air inlet of the fuel cell stack. It also includes a main intercooler, which is located between the second outlet of the auxiliary intercooler and the air inlet of the humidifier. The inlet of the main intercooler is connected to the second outlet of the auxiliary intercooler, and the outlet of the main intercooler is connected to the air inlet of the humidifier. A three-way valve is installed between the air compressor and the auxiliary intercooler. One outlet of the three-way valve is connected to the second inlet of the auxiliary intercooler, and the other outlet of the three-way valve is connected to the exhaust pipe. A throttle valve is installed on the pipe connecting the exhaust port of the humidifier and the exhaust pipe. An exhaust manifold is installed on the exhaust pipe, and the exhaust port of the humidifier is connected to the exhaust manifold.

2. The air heating device according to claim 1, characterized in that, A flow meter is installed at the inlet of the air compressor, and the outlet of the flow meter is connected to the inlet of the air compressor.

3. The air heating device according to claim 1, characterized in that, The high-temperature air generated by the air compressor heats the air at the fuel cell outlet through the auxiliary intercooler. The air at the fuel cell outlet exchanges heat with the high-temperature air output by the air compressor. The high-temperature air output by the air compressor is cooled by the main intercooler to obtain cooled air. The cooled air is input into the air inlet of the humidifier. The cooled air is obtained by reducing the high-temperature air output by the air compressor to meet the set temperature of the fuel cell inlet. The heated fuel cell outlet air is fed into the wet inlet of the humidifier. The heated fuel cell outlet air humidifies the cooled air in the humidifier and then the humidified cooled air is fed into the fuel cell.

4. A fuel cell, characterized in that, Includes the air heating device as described in any one of claims 1 to 3.

5. A vehicle, characterized in that, Includes the air heating device as described in any one of claims 1 to 3.

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