Novel air-cooling hybrid cooling type proton exchange membrane fuel cell stack based on micro heat pipe array and management method

Abstract

The invention discloses a novel air-cooling hybrid cooling type proton exchange membrane fuel cell stack based on a micro heat pipe array and a management method, and relates to the technical field of fuel cell thermal management. Comprising a fuel cell stack and a heat dissipation device, the fuel cell stack comprises two end plates, a collector plate and a proton exchange membrane fuel single cell; the heat dissipation device comprises a micro heat pipe array, a mixed cooling fan and a fan cover; a plurality of proton exchange membrane fuel single cells and micro heat pipe arrays are alternately arranged between the two end plates, the parts, attached to the proton exchange membrane fuel single cells, of the micro heat pipe arrays serve as micro heat pipe array evaporation sections, and the parts, outwards extending out of the proton exchange membrane fuel single cells, of the micro heat pipe arrays serve as micro heat pipe array condensation sections; the mixed cooling fan is installed over the micro heat pipe array and used for supplying air to the condensation section of the micro heat pipe array. According to the invention, not only can the purpose of heat dissipation be realized, but also rapid heating and starting of the electric pile can be realized in a low-temperature environment by switching the air flowing direction.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell thermal management, and in particular to a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array and a management method thereof. Background Art

[0002] Currently, the methods for solving the problems of thermal management and performance improvement of air-cooled proton exchange membrane fuel cells can be divided into three categories: First, adjusting the air supply of PEMFC, by optimizing the air flow rate, pressure, etc., to improve the heat dissipation and oxidant supply of the battery, thereby improving performance and thermal management efficiency. Second, improving the flow field design of the battery, by optimizing the flow field structure (such as the shape, size, and distribution of the flow channels), to enhance the uniform distribution of the reaction gas and cooling air, and improve the thermal management and electrochemical performance of the battery. Third, adding an external heat exchanger, by integrating an external heat exchanger such as fins, to enhance the heat dissipation capacity of the battery, effectively reduce the operating temperature, and improve the overall performance. However, the limitations of these methods are obvious. The first method can only control the temperature of the stack, but cannot improve the overall heat dissipation level of the stack. Although this method is simple, the improvement of the heat dissipation capacity is limited. The second method, although it has a certain improvement in the heat dissipation and performance of the stack, will significantly increase the air flow resistance in the flow channels, resulting in a relatively low level of the load current density of the stack. The third thermal management method is accompanied by additional power-consuming devices, resulting in an increase in parasitic power, thus affecting the net power generation capacity of the stack. In addition, the existing air-cooled PEMFC stacks do not achieve preheating of the stack through their own fans in low-temperature environments, which makes it difficult for the stack to start quickly and reach the standard operating conditions under low-temperature conditions.

[0003] Therefore, providing a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array and a management method thereof to solve the difficulties existing in the prior art is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array and a management method thereof, which can not only achieve the purpose of heat dissipation, but also realize the rapid heating and startup of the stack in a low-temperature environment by switching the air flow direction.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array, which includes a fuel cell stack and a heat dissipation device; The fuel cell stack includes two end plates, current collector plates, and proton exchange membrane fuel single cells; the heat dissipation device includes a micro heat pipe array, a hybrid cooling fan, and a wind cover; multiple proton exchange membrane fuel single cells and the micro heat pipe array are alternately arranged between the two end plates, and the part of the micro heat pipe array in contact with the proton exchange membrane fuel single cell serves as the evaporation section of the micro heat pipe array, and the part extending out of the proton exchange membrane fuel single cell serves as the condensation section of the micro heat pipe array; the hybrid cooling fan exhausts air bidirectionally, is installed directly above the micro heat pipe array, exhausts air upward during cooling, and blows air downward during preheating.

[0006] Optionally, the proton exchange membrane fuel single cell includes a bipolar plate and a membrane electrode assembly. The bipolar plate includes a cathode plate and an anode plate. An anode plate groove is provided on the back plate of the anode plate and is in complete contact with the micro heat pipe array.

[0007] Optionally, the micro heat pipe array is a smooth flat heat conductor made of integrally thermoformed aluminum. Multiple micro heat pipe array microchannels and micro fins are provided inside the micro heat pipe array. A non-conductive liquid with a boiling point of 30°C to 130°C at normal pressure is filled in each micro heat pipe array microchannel as the phase change medium.

[0008] Optionally, the cathode plate is provided with a cathode air flow channel, and the cathode air flow channel is parallel to the air flowing into the fuel cell stack.

[0009] A management method for a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array, which is applied to the novel air-cooled hybrid cooling proton exchange membrane fuel cell stack described in any one of the above, includes heat dissipation management and preheating management: The heat dissipation management includes that the hybrid cooling fan sucks air into the cathode air flow channel, so that the air flow direction is the same as the gravity direction. The air serves as the oxidant required for the electrochemical reaction of the fuel cell stack and cools the fuel cell stack, and then continues to pass through the condensation section of the micro heat pipe array for secondary cooling; The preheating management includes making the hybrid cooling fan work in the reverse direction, so that the air flow direction is opposite to the gravity direction to achieve rapid preheating.

[0010] As can be seen from the above technical solutions, compared with the prior art, the present invention provides a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array and a management method, which has the following beneficial effects: 1) The present invention does not require an additional fan for the condensation section of the micro heat pipe array, but uses the air flowing out of the cathode channel to couple the heat dissipation of the condensation section of the micro heat pipe array, and the oxidant supply and heat dissipation of the novel air-cooled hybrid cooling proton exchange membrane fuel cell stack are completed by the same set of fans at the same time; 2) The fan can provide a more uniform air supply for the hybrid cooling stack, thereby achieving a more uniform temperature distribution and voltage distribution; 3) The hybrid cooling stack of the present invention can not only achieve the purpose of heat dissipation, but also realize the rapid warming and startup of the fuel cell stack in a low-temperature environment by switching the air flow direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0012] Figure 1 FIG. is a schematic diagram of the overall structure of a novel air-cooled hybrid cooling proton exchange membrane fuel cell stack integrating a micro heat pipe array disclosed by the present invention; Figure 2 FIG. is an internal unfolded view of a new generation proton exchange membrane fuel cell stack disclosed by the present invention; Figure 3 FIG. is a diagram of a micro heat pipe array embedded in an anode plate groove disclosed by the present invention; Figure 4 FIG. is an internal structure diagram of the micro heat pipe array disclosed by the present invention; Among them, 1 is a hybrid cooling fan; 2 is a wind hood; 3 is a micro heat pipe array; 4 is a bipolar plate; 4-1 is a cathode plate; 4-2 is an anode plate; 5 is a membrane electrode assembly; 6 is a micro channel of the micro heat pipe array. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0013] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0014] Such as Figures 1-4As shown in the figure, the present invention discloses a novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array, which includes a fuel cell stack and a heat dissipation device; The fuel cell stack includes two end plates, a current collector plate, and a proton exchange membrane fuel single cell; the heat dissipation device includes a micro heat pipe array 3, a hybrid cooling fan 1, and a wind cover 2; multiple proton exchange membrane fuel single cells and the micro heat pipe array 3 are alternately arranged between the two end plates. The part of the micro heat pipe array 3 that fits the proton exchange membrane fuel single cell serves as the evaporation section of the micro heat pipe array 3, and the part that extends out of the proton exchange membrane fuel single cell serves as the condensation section of the micro heat pipe array 3; the hybrid cooling fan 1 discharges air bidirectionally, is installed directly above the micro heat pipe array 3, and discharges air upward during cooling and blows air downward during preheating.

[0015] Furthermore, the fuel cell stack is designed with a rated power of 1 kW and is assembled from 50 proton exchange membrane fuel single cells and 50 micro heat pipe arrays 3. Three hybrid cooling fans 1 are provided, and the wind cover 2 is a fairing to ensure that the hybrid cooling fan 1 provides sufficient air flow into the cathode air flow channel of the cathode plate 4-1.

[0016] Furthermore, the proton exchange membrane fuel single cell includes a bipolar plate 4 and a membrane electrode assembly 7. The bipolar plate 4 includes a cathode plate 4-1 and an anode plate 4-2. The back plate of the anode plate 4-2 is provided with an anode plate groove, which fits perfectly with the micro heat pipe array 3.

[0017] Furthermore, the micro heat pipe array 3 is a smooth flat heat conductor made of integrally thermoformed aluminum. The micro heat pipe array 3 has multiple micro heat pipe array microchannels 6 and micro fins inside, and has excellent compressive performance. Each micro heat pipe array microchannel 6 is filled with a non-conductive liquid with a boiling point of 30-130°C under normal pressure as a phase change medium.

[0018] Specifically, the length, width, and thickness of the micro heat pipe array 3 are 200 mm, 60 mm, and 2 mm respectively. 90 mm of the micro heat pipe array 3 is embedded in the anode plate groove as the evaporation section of the micro heat pipe array 3, and 110 mm is exposed to the air as the condensation section of the micro heat pipe array 3; the width of the micro heat pipe array microchannel 6, the width of the micro fin, and the edge width are 2.2 mm, 0.3 mm, and 0.5 mm respectively.

[0019] Furthermore, the cathode plate 4-1 is provided with a cathode air flow channel, and the cathode air flow channel is parallel to the air flowing into the fuel cell stack.

[0020] A management method for a novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array, which is applied to the novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array described in any one of the above, includes heat dissipation management and preheating management: Thermal management includes a hybrid cooling fan 1 sucking air into the cathode air flow channel, such that the air flow direction is consistent with the direction of gravity. The air serves as the oxidant required for the electrochemical reaction of the fuel cell stack and cools the fuel cell stack, and then continues to pass through the condensation section of the micro heat pipe array 3 for secondary cooling; Preheating management includes making the hybrid cooling fan 1 operate in reverse, such that the air flow direction is opposite to the direction of gravity, to achieve rapid preheating.

[0021] In a specific embodiment, a new air-cooled hybrid cooling proton exchange membrane fuel cell stack is started. During the operation of the fuel cell stack, heat is generated. The working fluid inside the evaporation section of the micro heat pipe array 3 absorbs the heat generated by the stack and evaporates to the condensation section of the micro heat pipe array 3. The gaseous working fluid is cooled to a liquid state in the condensation section of the micro heat pipe array 3 and releases heat to the outside of the stack, and then flows back to the evaporation section of the micro heat pipe array 3, thereby forming a cycle of heat transfer and heat dissipation. The hybrid cooling fan 1 is started as an air suction type, and the air flow direction is opposite to the direction of gravity. The ambient air flows into the cathode plate air flow channel under the action of the hybrid cooling fan 1, provides the oxidant required for the electrochemical reaction of the new air-cooled hybrid cooling proton exchange membrane fuel cell stack and first cools the fuel cell stack, and then continues to pass through the condensation section of the micro heat pipe array 3 for secondary cooling. During the whole process, the air serves as both an oxidant and a coolant, providing hybrid cooling for the proton exchange membrane fuel cell stack. The micro heat pipe array 3 has a high thermal conductivity, and the temperature of the condensation section of the micro heat pipe array 3 is almost the same as the temperature of the fuel cell stack. Therefore, the air flowing out of the cathode channel is sufficient to cool the condensation section of the micro heat pipe array 3.

[0022] In another specific embodiment, a new air-cooled hybrid cooling proton exchange membrane fuel cell stack is started. During the operation of the fuel cell stack, heat is generated. The hybrid cooling fan 1 is started as a blowing type, and the air flow direction is consistent with the direction of gravity. The new air-cooled hybrid cooling proton exchange membrane fuel cell stack can achieve its own rapid preheating under low-temperature conditions, thereby improving the performance during low-temperature startup.

[0023] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A novel air-cooled hybrid cooling proton exchange membrane fuel cell stack based on a micro heat pipe array, characterized in that It includes a fuel cell stack and a heat dissipation device; The fuel cell stack includes two end plates, a current collector plate, and a proton exchange membrane fuel single cell; the heat dissipation device includes a micro heat pipe array (3), a hybrid cooling fan (1), and a wind cover (2); multiple proton exchange membrane fuel single cells and the micro heat pipe array (3) are alternately arranged between the two end plates. The part of the micro heat pipe array (3) that fits the proton exchange membrane fuel single cell serves as the evaporation section of the micro heat pipe array (3), and the part that extends out of the proton exchange membrane fuel single cell serves as the condensation section of the micro heat pipe array (3); the hybrid cooling fan (1) blows air bidirectionally, is installed directly above the micro heat pipe array (3), and exhausts air upward during cooling and blows air downward during preheating.

2. A novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array according to claim 1, characterized in that The proton exchange membrane fuel single cell includes a bipolar plate (4) and a membrane electrode assembly (5). The bipolar plate (4) includes a cathode plate (4-1) and an anode plate (4-2). An anode plate groove is provided on the back plate of the anode plate (4-2) and is completely fitted with the micro heat pipe array (3).

3. A novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array according to claim 1, characterized in that The micro heat pipe array (3) is a smooth flat heat conductor made of integrally thermoformed aluminum. The micro heat pipe array (3) has multiple micro heat pipe array microchannels (6) and micro fins inside. Each micro heat pipe array microchannel (6) is filled with a non-conductive liquid with a boiling point of 30°C - 130°C under normal pressure as the phase change medium.

4. A novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array according to claim 2, characterized in that The cathode plate (4-1) is provided with a cathode air flow channel, and the cathode air flow channel is parallel to the air flowing into the fuel cell stack.

5. A management method for a novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array, which is applied to a novel air-cooled hybrid-cooled proton exchange membrane fuel cell stack based on a micro heat pipe array according to any one of claims 1-4, and is characterized in that, It includes heat dissipation management and preheating management: Heat dissipation management includes the hybrid cooling fan (1) sucking air into the cathode air flow channel, so that the air flow direction is the same as the direction of gravity. The air serves as the oxidant required for the electrochemical reaction of the fuel cell stack and cools the fuel cell stack, and then continues to be cooled secondary through the condensation section of the micro heat pipe array (3); Preheating management includes making the hybrid cooling fan (1) work in the reverse direction, so that the air flow direction is opposite to the direction of gravity, to achieve rapid preheating.

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