Cathode closed type air-cooled fuel cell system

Abstract

The invention provides a cathode closed type air-cooled fuel cell system, the output end of a hydrogen storage tank is connected to an anode inlet pipeline of a fuel cell stack, the system comprises an air blower, a three-way valve and a spraying pipe, and the output end of the air blower is respectively communicated to the anode inlet pipeline and a cathode inlet pipeline of the fuel cell stack through pipelines; the spraying pipe is arranged above a cooling flow channel of the fuel cell stack; a first interface of the three-way valve is connected to a cathode outlet pipeline of the fuel cell stack, a second interface of the three-way valve leads to an anode inlet pipeline of the fuel cell stack through a pipeline, and a third interface of the three-way valve is connected to the spraying pipe. According to the invention, air discharged by the cathode of the stack is guided to the inlet of the anode of the stack, and the anode can be thoroughly blow-dried by high-flow high-pressure purging of the blower, so that zero-hydrogen purging of the anode by the cathode blower is realized by using the two-position three-way valve of the cathode, and the bottleneck of air-cooling heat dissipation is broken through by active cooling of reaction water discharged by the cathode of the stack; the system structure is simplified, and the manufacturing cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to a cathode closed-loop air-cooled fuel cell system. Background Technology

[0002] Traditional low-power air-cooled fuel cells rely on air convection for heat dissipation. Adding heat sinks or fans only provides a limited improvement in heat dissipation efficiency, and overheating is still likely in high-power-density scenarios. Moreover, the low heat dissipation efficiency leads to a rapid increase in stack temperature, especially in high-temperature environments or under high loads, affecting output stability and lifespan. Furthermore, after system shutdown, especially in sub-zero environments, periodic purging is required to remove anode water buildup. Existing systems mostly use pure hydrogen purging or additional hydrogen recirculation pumps. The former wastes hydrogen and reduces system efficiency, while the latter increases cost and power consumption, violating the principles of miniaturization and low cost for low-power systems. While using hydrogen recirculation pumps can reduce hydrogen consumption, they are bulky, consume a lot of power, and are expensive, making them unsuitable for low-power systems. Pure hydrogen purging, on the other hand, reduces hydrogen utilization by 10%-30%. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention provides a cathode closed-loop air-cooled fuel cell system. It utilizes a two-position three-way valve at the cathode to achieve zero-hydrogen purging of the anode by a cathode blower, and uses active cooling with reaction water to overcome the bottleneck of air-cooled heat dissipation, thereby simplifying the system structure and reducing manufacturing costs.

[0004] This invention proposes a cathode-closed air-cooled fuel cell system. The output end of a hydrogen storage tank is connected to the anode inlet pipe of the fuel cell stack. The system includes a blower, a three-way valve, and a spray pipe. The output end of the blower is connected to both the anode inlet pipe and the cathode inlet pipe of the fuel cell stack via pipes. The spray pipe is positioned above the cooling channels of the fuel cell stack. The first port of the three-way valve is connected to the cathode outlet pipe of the fuel cell stack, the second port of the three-way valve is connected to the anode inlet pipe of the fuel cell stack via a pipe, and the third port of the three-way valve is connected to the spray pipe.

[0005] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, an air filter is connected to the input end of the blower.

[0006] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, the spray pipes are arranged linearly and uniformly.

[0007] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, the output end of the hydrogen storage tank is connected to a first control valve.

[0008] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, one end of the first control valve is connected to a pressure sensor.

[0009] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, the hydrogen discharge port of the fuel cell stack is connected to a second control valve.

[0010] Preferably, in the cathode closed-loop air-cooled fuel cell system provided by the present invention, the three-way valve is a two-position three-way valve.

[0011] Preferably, the cathode closed-loop air-cooled fuel cell system provided by the present invention has a cooling fan installed above the fuel cell stack.

[0012] As can be seen, the cathode closed-loop air-cooled fuel cell system provided by this invention guides the air discharged from the cathode of the fuel cell stack to the anode inlet of the fuel cell stack. The anode can be thoroughly dried by high-pressure purging with a large flow rate of blower. Thus, the cathode blower can achieve zero-hydrogen purging of the anode by the cathode two-position three-way valve. The reaction water discharged from the cathode of the fuel cell stack is used for active cooling to overcome the bottleneck of air-cooled heat dissipation, simplify the system structure and reduce manufacturing costs. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 The diagram shown is a schematic representation of the structural framework of a cathode closed-loop air-cooled fuel cell system according to an embodiment of the present invention.

[0015] The reference numerals in the accompanying drawings are as follows:

[0016] 1. Hydrogen storage tank; 2. Fuel cell stack; 3. Blower; 4. Three-way valve; 5. Spray pipe; 6. Air filter; 7. First control valve; 8. Pressure sensor; 9. Second control valve; 10. Cooling fan. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] It should be noted that, in this document, 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. In this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0019] In existing technologies, adding heat sinks or fans to the system can only improve heat dissipation efficiency to a limited extent. In high-power-density scenarios, overheating is still likely, and the low heat dissipation efficiency leads to a rapid increase in fuel cell temperature, especially under high-temperature environments or high loads, affecting output stability and lifespan. Furthermore, many systems use pure hydrogen purging or additional hydrogen circulation pumps. The former wastes hydrogen and reduces system efficiency, while the latter increases cost and power consumption, violating the principles of miniaturization and low cost for low-power systems. While using a hydrogen circulation pump can reduce hydrogen consumption, it is bulky, consumes a lot of power, and is expensive, making it unsuitable for low-power systems. Pure hydrogen purging, on the other hand, reduces hydrogen utilization by 10%-30%. The embodiments of this invention provide the following solution:

[0020] like Figure 1 As shown, this embodiment of the invention provides a cathode-closed air-cooled fuel cell system. The output end of the hydrogen storage tank 1 is connected to the anode inlet pipe of the fuel cell stack 2. The system includes a blower 3, a three-way valve 4, and a spray pipe 5. The output end of the blower 3 is connected to both the anode inlet pipe and the cathode inlet pipe of the fuel cell stack 2 via pipes. The spray pipe 5 is positioned above the cooling channels of the fuel cell stack 2. The first port of the three-way valve 4 is connected to the cathode outlet pipe of the fuel cell stack 2, the second port of the three-way valve 4 is connected to the anode inlet pipe of the fuel cell stack 2 via a pipe, and the third port of the three-way valve 4 is connected to the spray pipe.

[0021] It should be noted that the system achieves zero hydrogen purging of the anode, allows the operating environment temperature to rise by 10-15°C through evaporative cooling via spray pipes, and reduces the number of components by 30% and costs by 25%.

[0022] Specifically, after the system operation is suspended, the controller switches the three-way valve 4 to divert the dry air discharged from the cathode outlet of the fuel cell stack 2 to the anode inlet of the fuel cell stack 2. The high-flow-rate blower 3 then performs high-pressure purging to thoroughly dry the anode. This avoids the use of pure hydrogen for purging, saving more than 30% of hydrogen. Reusing the existing blower eliminates the need for an additional hydrogen circulation pump, reducing costs and power consumption. The large airflow improves purging efficiency and shortens the purging cycle by 20%-50%. Furthermore, the liquid water discharged from the cathode outlet pipe of the fuel cell stack 2 is separated into the spray pipe 5 via the three-way valve 4. This reacted liquid water is sprayed onto the surface of the cooling channels, enhancing heat dissipation through evaporative heat absorption. The spray water also simultaneously cleans the heat dissipation channels, maintaining long-term heat dissipation performance. Directly utilizing the reaction byproduct water eliminates the need for an external water source, increasing cooling efficiency by 3-5 times compared to pure air cooling and allowing for a more than 15% increase in stack power density.

[0023] In some embodiments, the input end of the blower 3 is connected to an air filter 6, thereby filtering the incoming air and improving the stability of the overall reaction.

[0024] In some embodiments, the spray pipes 5 are arranged linearly and uniformly, and their space occupation is reduced by rationally planning the layout.

[0025] In some embodiments, the output end of the hydrogen storage tank 1 is connected to a first control valve 7, thereby allowing for better control of the amount of hydrogen output.

[0026] In some embodiments, a pressure sensor 8 is connected to one end of the first control valve 7, thereby enabling real-time monitoring of the output hydrogen pressure and improving the reliability of the entire system.

[0027] In some embodiments, the hydrogen discharge port of the fuel cell stack 2 is connected to a second control valve 9, thereby allowing for better control of the amount of hydrogen discharged.

[0028] In some embodiments, the three-way valve 4 is a two-position three-way valve, which allows for better control of the three-way valve.

[0029] In some embodiments, a cooling fan 10 is provided above the fuel cell stack 2 to provide auxiliary cooling for the fuel cell stack 2.

[0030] In summary, the embodiments of the present invention provide a cathode closed-loop air-cooled fuel cell system. The air exhausted from the cathode of the fuel cell stack is diverted to the anode inlet of the fuel cell stack. The anode can be thoroughly dried by high-pressure purging with a high-flow-rate blower. The cathode blower can achieve zero-hydrogen purging of the anode by a two-position three-way valve. The reaction water exhausted from the cathode of the fuel cell stack is used for active cooling to overcome the bottleneck of air-cooled heat dissipation, simplify the system structure and reduce manufacturing costs.

[0031] The above description is merely a specific embodiment of this application, and the scope of protection of this application is not limited thereto. Those skilled in the art can make changes or substitutions within the technical scope disclosed in this application, and all such changes or substitutions should be within the scope of protection of this application.

[0032] Those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the invention and form different embodiments.

[0033] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cathode-closed air-cooled fuel cell system, wherein the output end of a hydrogen storage tank (1) is connected to the anode inlet pipe of a fuel cell stack (2), characterized in that, The assembly includes a blower (3), a three-way valve (4), and a spray pipe (5). The output end of the blower (3) is connected to the anode inlet pipe and the cathode inlet pipe of the fuel cell stack (2) through pipelines. The spray pipe (5) is located above the cooling channel of the fuel cell stack (2). The first port of the three-way valve (4) is connected to the cathode outlet pipe of the fuel cell stack (2), the second port of the three-way valve (4) is connected to the anode inlet pipe of the fuel cell stack (2) through a pipeline, and the third port of the three-way valve (4) is connected to the spray pipe.

2. The cathode closed-loop air-cooled fuel cell system according to claim 1, characterized in that, An air filter (6) is connected to the input end of the blower (3).

3. The cathode closed-loop air-cooled fuel cell system according to claim 1, characterized in that, The spray pipes (5) are arranged in a linear and uniform manner.

4. The cathode closed-loop air-cooled fuel cell system according to claim 1, characterized in that, The output end of the hydrogen storage tank (1) is connected to a first control valve (7).

5. The cathode closed-loop air-cooled fuel cell system according to claim 4, characterized in that, A pressure sensor (8) is connected to one end of the first control valve (7).

6. The cathode-closed air-cooled fuel cell system according to claim 1, characterized in that, The hydrogen vent of the fuel cell stack (2) is connected to a second control valve (9).

7. The cathode closed-loop air-cooled fuel cell system according to claim 1, characterized in that, The three-way valve (4) is a two-position three-way valve.

8. The cathode closed-loop air-cooled fuel cell system according to claim 1, characterized in that, A cooling fan (10) is provided above the fuel cell stack (2).

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