Fuel cell system integrating ac impedance and spray humidification and control method

Abstract

The application provides a fuel cell system integrated with alternating current impedance and spray humidification and a control method. The fuel cell system integrated with alternating current impedance and spray humidification comprises an alternating current impedance detection device, a membrane tube humidifier, a spray humidification device and a controller. The alternating current impedance detection device is electrically connected with a stack and is used for detecting high-frequency impedance of the stack. The membrane tube humidifier is in communication with the stack through a pipeline and is used for humidifying air at an air inlet of the stack. The spray humidification device is arranged at an inlet of the membrane tube humidifier and is used for humidifying the air at the air inlet of the stack. The alternating current impedance detection device and the spray humidification device are electrically connected with the controller. The application solves the problems of performance decline and service life attenuation of the fuel cell caused by membrane dryness.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell technology, and in particular relates to a fuel cell system and control method that integrates AC impedance and spray humidification. Background Technology

[0002] During fuel cell operation, hydrogen and air undergo a redox reaction upon entering the cell, producing electricity and water. If the electrolyte membrane is too dry, its permeability to water molecules will be affected, leading to the accumulation of hydrogen and air on the membrane, reducing the reaction rate and impacting the fuel cell's electrochemical performance. Therefore, to maintain the permeability and reaction rate of the electrolyte membrane, a certain level of humidity needs to be increased during fuel cell operation to improve the diffusion rate of water molecules within the membrane and maintain its permeability. Currently, the fuel cell industry primarily uses membrane tube humidifiers to externally humidify the air entering the stack. However, membrane tube humidifiers are bulky, expensive, and suffer from deterioration in humidification performance over time. Furthermore, as a passive humidification device, precise control of the actual humidification amount is difficult to achieve. Summary of the Invention

[0003] In view of the problems existing in the prior art, the present invention provides a fuel cell system and control method that integrates AC impedance and spray humidification, which at least partially solves the problems of reduced fuel cell performance and lifespan caused by membrane drying in the prior art.

[0004] In a first aspect, embodiments of this disclosure provide a fuel cell system integrating AC impedance and spray humidification, including: an AC impedance detection device, a membrane tube humidifier, a spray humidification device, and a controller;

[0005] The AC impedance detection device is electrically connected to the fuel cell stack, and the AC impedance detection device is used to detect the high-frequency impedance of the fuel cell stack.

[0006] The membrane tube humidifier is connected to the fuel cell stack via a pipe and is used to humidify the air at the fuel cell stack's air inlet.

[0007] The spray humidification device is installed at the inlet of the membrane tube humidifier and is used to humidify the air at the air inlet of the fuel cell stack.

[0008] The AC impedance detection device and the spray humidification device are electrically connected to the controller.

[0009] Optionally, the spray humidification device includes an atomizing nozzle, a water pump, and a water storage tank;

[0010] Under the action of the water pump, the water in the water storage tank humidifies the air at the air inlet of the fuel cell stack after passing through the atomizing nozzle.

[0011] Optionally, a drain outlet is provided at the bottom of the water storage tank, and a drain valve is provided on the drain outlet at the bottom of the water storage tank.

[0012] Optionally, it also includes an intercooler, a flow meter, and an air filter. Outside air is sequentially passed through the air filter and the flow meter and then delivered to the compressor impeller. The air output from the compressor impeller is then delivered to the intercooler after passing through a spray humidification device. The gas cooled by the intercooler is then delivered to the membrane tube humidifier.

[0013] Optionally, the water storage tank is a constant temperature water storage tank.

[0014] Optional components also include an air compressor and a water distribution unit;

[0015] The gas discharged from the fuel cell stack is sent to the water separator after passing through the turbine end of the air compressor. The water separated by the water separator enters the water storage tank.

[0016] Optionally, an exhaust throttle valve is provided between the membrane tube humidifier and the turbine end of the air compressor.

[0017] Secondly, embodiments of this disclosure also provide a fuel cell control method integrating AC impedance and spray humidification, used in any of the systems described in the first aspect, the method comprising:

[0018] The high-frequency impedance of the fuel cell is obtained by impedance detection, and the high-frequency impedance is compared with the target impedance at the current operating point.

[0019] When the high-frequency impedance is greater than the target impedance at the current operating point, the spray humidification device is activated.

[0020] When the high-frequency impedance is less than the target impedance at the current operating point, the spray humidification device is turned off, and the fuel cell is passively humidified through the membrane tube humidifier.

[0021] Optionally, before the step of obtaining the high-frequency impedance by impedance detection of the fuel cell, the following steps are included:

[0022] Obtain the status of the fuel cell to determine whether the fuel cell is in operation.

[0023] Thirdly, embodiments of this disclosure also provide an engine, including the fuel cell system with integrated AC impedance and spray humidification as described in any of the first aspects.

[0024] This invention provides a fuel cell system and control method integrating AC impedance and spray humidification. The integrated AC impedance and spray humidification fuel cell system utilizes an integrated AC impedance detection and spray humidification device. High-frequency impedance is used to characterize the dryness or wetness of the proton exchange membrane, and the spray humidification device enables active closed-loop control of air humidification, thus solving the performance degradation and lifespan reduction problems caused by membrane dryness in fuel cells. Attached Figure Description

[0025] 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.

[0026] Figure 1 A structural block diagram of a fuel cell system integrating AC impedance and spray humidification provided in an embodiment of this disclosure;

[0027] Figure 2 A flowchart illustrating a fuel cell control method integrating AC impedance and spray humidification;

[0028] 1- Membrane tube humidifier; 2- Intercooler; 3- Atomizing nozzle; 4- Tail exhaust throttle valve; 5- Water pump; 6- Air compressor; 7- Air filter; 8- Flow meter; 9- Water distributor; 10- Water storage tank; 11- Drain valve. Detailed Implementation

[0029] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] like Figure 1 As shown, this embodiment discloses a fuel cell system integrating AC impedance and spray humidification, including: an AC impedance detection device, a membrane tube humidifier, a spray humidification device, and a controller;

[0035] The AC impedance detection device is electrically connected to the fuel cell stack, and the AC impedance detection device is used to detect the high-frequency impedance of the fuel cell stack.

[0036] The membrane tube humidifier is connected to the fuel cell stack via a pipe and is used to humidify the air at the fuel cell stack's air inlet.

[0037] The spray humidification device is installed at the inlet of the membrane tube humidifier and is used to humidify the air at the air inlet of the fuel cell stack.

[0038] The AC impedance detection device and the spray humidification device are electrically connected to the controller. Figure 1 The CVM in this context refers to the AC impedance detection device, which is integrated into the fuel cell stack.

[0039] Optionally, the spray humidification device includes an atomizing nozzle, a water pump, and a water storage tank;

[0040] Under the action of the water pump, the water in the water storage tank humidifies the air at the air inlet of the fuel cell stack after passing through the atomizing nozzle.

[0041] Optionally, a drain outlet is provided at the bottom of the water storage tank, and a drain valve is installed on the drain outlet at the bottom of the water storage tank. The water source for the water storage tank comes from the tail drain of the electric stack.

[0042] Optionally, it also includes an intercooler, a flow meter, and an air filter. Outside air passes through the air filter and flow meter in sequence before being delivered to the compressor impeller. The air output from the compressor impeller is then delivered to the intercooler after passing through a spray humidification device. The gas cooled by the intercooler is then delivered to the membrane tube humidifier. The flow meter includes an ambient temperature measuring point.

[0043] Optionally, the water storage tank is a constant temperature water storage tank.

[0044] Optional components also include an air compressor and a water distribution unit;

[0045] The gas discharged from the fuel cell stack is sent to the water separator after passing through the turbine end of the air compressor. The water separated by the water separator enters the water storage tank.

[0046] Optionally, an exhaust throttle valve is provided between the membrane tube humidifier and the turbine end of the air compressor.

[0047] like Figure 2 As shown, this embodiment also discloses a fuel cell control method integrating AC impedance and spray humidification, including:

[0048] The high-frequency impedance of the fuel cell is obtained by impedance detection, and the high-frequency impedance is compared with the target impedance at the current operating point.

[0049] When the high-frequency impedance is greater than the target impedance at the current operating point, the spray humidification device is activated.

[0050] When the high-frequency impedance is less than the target impedance at the current operating point, the spray humidification device is turned off, and the fuel cell is passively humidified through the membrane tube humidifier.

[0051] Optionally, before the step of obtaining the high-frequency impedance by impedance detection of the fuel cell, the following steps are included:

[0052] Obtain the status of the fuel cell to determine whether the fuel cell is in operation.

[0053] When the fuel cell is in operation, impedance detection is performed on the fuel cell.

[0054] The fuel cell system and control method integrating AC impedance and spray humidification disclosed in this embodiment, by integrating AC impedance detection function and adding a spray humidification device on the basis of conventional membrane tube humidification, differs from the current mainstream passive humidification status. Based on high-frequency impedance judgment, it realizes active, closed-loop humidification control technology, which helps to solve the problem of fuel cell performance degradation and lifespan reduction caused by membrane dryness.

[0055] 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.

[0056] 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. Words such as "including," "comprising," "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 explicitly 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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. A fuel cell system integrating AC impedance and spray humidification, characterized in that, include: AC impedance detection device, membrane tube humidifier, spray humidifier and controller; The AC impedance detection device is electrically connected to the fuel cell stack, and the AC impedance detection device is used to detect the high-frequency impedance of the fuel cell stack. The membrane tube humidifier is connected to the inlet and outlet of the fuel cell stack via pipes and is used to humidify the air at the air inlet of the fuel cell stack. The spray humidification device is installed at the inlet of the membrane tube humidifier and is used to humidify the air at the air inlet of the fuel cell stack. The AC impedance detection device and the spray humidification device are electrically connected to the controller; The system is configured as follows: The high-frequency impedance of the fuel cell is obtained by impedance detection, and the high-frequency impedance is compared with the target impedance at the current operating point. When the high-frequency impedance is greater than the target impedance at the current operating point, the spray humidification device is activated. When the high-frequency impedance is less than the target impedance at the current operating point, the spray humidification device is turned off, and the fuel cell is passively humidified through the membrane tube humidifier.

2. The fuel cell system integrating AC impedance and spray humidification according to claim 1, characterized in that, The spray humidification device includes an atomizing nozzle, a water pump, and a water storage tank; Under the action of the water pump, the water in the water storage tank humidifies the air at the air inlet of the fuel cell stack after passing through the atomizing nozzle.

3. The fuel cell system integrating AC impedance and spray humidification according to claim 2, characterized in that, A drain outlet is provided at the bottom of the water storage tank, and a drain valve is installed on the drain outlet at the bottom of the water storage tank.

4. The fuel cell system integrating AC impedance and spray humidification according to claim 2, characterized in that, It also includes an intercooler, a flow meter, and an air filter. External air is sequentially passed through the air filter and the flow meter and then delivered to the compressor impeller. The air output from the compressor impeller is then delivered to the intercooler after passing through a spray humidification device. The gas cooled by the intercooler is then delivered to the membrane tube humidifier.

5. The fuel cell system integrating AC impedance and spray humidification according to claim 2, characterized in that, The water storage tank is a constant temperature water storage tank.

6. The fuel cell system integrating AC impedance and spray humidification according to claim 2, characterized in that, It also includes air compressors and water distribution components; The gas discharged from the fuel cell stack is sent to the water separator after passing through the turbine end of the air compressor. The water separated by the water separator enters the water storage tank.

7. The fuel cell system integrating AC impedance and spray humidification according to claim 5, characterized in that, An exhaust throttle valve is provided between the membrane tube humidifier and the turbine end of the air compressor.

8. The fuel cell system integrating AC impedance and spray humidification according to claim 1, characterized in that, The system is specifically configured as follows: Before obtaining the high-frequency impedance by impedance detection of the fuel cell, the fuel cell status is obtained to determine whether the fuel cell is in operation.

9. An engine, characterized in that, The fuel cell system comprising the integrated AC impedance and spray humidification as described in any one of claims 1 to 8.

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