Microchannel flow field bipolar plate structure

Abstract

This utility model relates to a microchannel flow channel, and more particularly to a microchannel flow channel bipolar plate structure, including an anode flow field plate, a proton exchange membrane, and a cathode flow field plate. The cathode flow field plate includes a first flow field plate, a second flow field plate, and a diaphragm. The first flow field plate has an air inlet and an air inlet channel inside. The second flow field plate has an air outlet and an air outlet channel inside. The diaphragm has through holes, and the air inlet channel and air outlet channel are connected through the through holes. The anode and cathode flow field plates have the same structure. Through the coordinated action of the first flow field plate, the second flow field plate, the diaphragm, the air inlet, the air inlet channel, the air outlet, the air outlet channel, and the through holes, this utility model can appropriately increase the gas pressure, promote gas flow distribution, accelerate the airflow velocity, reduce moisture residue, ensure that the electrode can fully utilize the gas, and reduce exhaust gas.

Description

Technical Field

[0001] This utility model relates to a microchannel flow channel, and more particularly to a microchannel flow channel bipolar plate structure. Background Technology

[0002] Currently, the bipolar plates widely used in proton exchange membrane fuel cells (PEMFCs) mainly include graphite (including pure graphite plates and graphite-polymer composite plates) bipolar plates, metal bipolar plates, metal-graphite composite bipolar plates, and bipolar plates injection-molded with polymer resin and graphite doping. Traditional flow field structures are generally: point-like, mesh-like, parallel groove, serpentine, interdigitated, and lung-shaped branching structures, etc.

[0003] In the prior art, the serpentine flow field structure can facilitate the discharge of water generated by the fuel cell and reduce liquid residue, while the straight-through smooth structure can shorten the flow channel distance, but it is prone to flow channel blockage due to water accumulation. When the flow channel is blocked, it will also cause the gas flow to be redistributed. Summary of the Invention

[0004] The purpose of this invention is to provide a microchannel bipolar plate structure that can promote gas flow distribution, reduce moisture residue in the channel, and ensure that the gas is fully utilized.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a microchannel bipolar plate structure is provided, including an anode flow field plate, a proton exchange membrane, and a cathode flow field plate. The cathode flow field plate includes a first flow field plate, a second flow field plate, and a diaphragm. An air inlet is provided on the first flow field plate, and an air inlet channel is provided inside the first flow field plate. An air outlet is provided on the second flow field plate, and an air outlet channel is provided inside the second flow field plate. A through hole is provided on the diaphragm, and the air inlet channel and the air outlet channel are connected through the through hole.

[0006] Optionally, the anode flow field plate and the cathode flow field plate have the same structure, and a cathode diffusion layer is fixedly disposed on the side of the proton exchange membrane near the cathode flow field plate, and an anode diffusion layer is fixedly disposed on the side of the proton exchange membrane near the anode flow field plate.

[0007] Optionally, the air inlet is connected to the air inlet channel, and the air outlet is connected to the air outlet channel.

[0008] Optionally, multiple air intake channels are provided, and the opening diameter of each of the multiple air intake channels near the air intake port is larger than the opening diameter of the other end.

[0009] Optionally, multiple air outlet channels are provided, and the internal corners of the multiple air outlet channels are all rounded.

[0010] Optionally, the diaphragm material is polyimide, and the flow field plate one and the flow field plate two are made of surface-modified metal. The surface-modified metal includes a metal body and a coating. The metal body is made of titanium alloy, and the coating is made of nickel plating or nickel alloy.

[0011] Optionally, the air inlet is located at the midpoint of the side of the flow field plate one away from the flow field plate two, and the air outlet is located at the midpoint of the side of the flow field plate two away from the flow field plate one.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] This invention utilizes the combined structure of flow field plate one, flow field plate two, diaphragm, air inlet, air inlet channel, air outlet, air outlet channel, and through hole. By combining straight and serpentine channels, the straight channel adopts a gradually narrowing structure, which can appropriately increase the air pressure, promote gas flow distribution, and accelerate the airflow speed. Combined with the rounded corners of the serpentine channel, it can further reduce moisture residue, ensure that the electrode can make full use of the gas, and reduce exhaust gas. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model, 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 this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the flow field plate of this utility model;

[0017] Figure 3 This is a schematic diagram of the flow field plate II of this utility model;

[0018] Figure 4 This is a cross-sectional structural diagram of the flow field plate one, flow field plate two, and diaphragm of this utility model.

[0019] In the figure: 1. Flow field plate one; 11. Air inlet; 12. Air inlet channel; 2. Flow field plate two; 21. Air outlet; 22. Air outlet channel; 3. Diaphragm; 31. Through hole; 4. Anode flow field plate; 5. Cathode diffusion layer; 6. Anode diffusion layer; 7. Proton exchange membrane; 8. Cathode flow field plate. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0022] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] Reference Figure 1-4 The present invention will now describe a microchannel bipolar plate structure provided by an embodiment of the present invention. A microchannel bipolar plate structure includes an anode flow field plate 4, a proton exchange membrane 7, and a cathode flow field plate 8. The cathode flow field plate 8 includes a flow field plate 1, a flow field plate 2, and a diaphragm 3. The flow field plate 1 and the flow field plate 2 are made of surface-modified metal, which includes a metal body and a coating. The metal body is made of titanium alloy, and the surface of the titanium alloy substrate can be coated with a corrosion-resistant coating by electroplating or sputtering. The coating material is nickel plating or a nickel alloy, wherein the nickel alloy is Ni-WP or Ni-Cu-P alloy, which can improve corrosion resistance and conductivity. The diaphragm 3 is made of polyimide. The flow field plate 1 has an air inlet 11 and an air inlet channel 12 inside. The flow field plate 2 has an air outlet 21 and an air outlet channel 22 inside. The diaphragm 3 has a through hole 31, and the air inlet channel 12 and the air outlet channel 22 are connected through the through hole 31.

[0025] The present invention provides a microchannel bipolar plate structure that, compared with the prior art, can promote gas flow distribution, reduce moisture residue in the channel, and ensure that the gas is fully utilized.

[0026] In another embodiment of this utility model, please refer to Figure 1 and Figure 4 The anode flow field plate 4 and the cathode flow field plate 8 have the same structure. The proton exchange membrane 7 is fixedly provided with a cathode diffusion layer 5 on the side near the cathode flow field plate 8, and the proton exchange membrane 7 is fixedly provided with an anode diffusion layer 6 on the side near the anode flow field plate 4. The above-mentioned multi-layered structures are all structural distributions of fuel cells in the prior art, and their detailed principles will not be described here. The air inlet 11 is located at the midpoint of the side of the flow field plate 1 away from the flow field plate 2, and the air outlet 21 is located at the midpoint of the side of the flow field plate 2 away from the flow field plate 1, so that the gas distribution is more uniform.

[0027] In another embodiment of this utility model, please refer to Figures 2 to 4 The air inlet 11 is connected to the air inlet channel 12, and the air outlet 21 is connected to the air outlet channel 22. There are multiple air inlet channels 12, and the opening diameter of the multiple air inlet channels 12 near the air inlet 11 is larger than the opening diameter of the other end. The gradually narrowing opening design can appropriately increase the air pressure, promote the gas flow distribution, and accelerate the airflow speed, so that the gas entering the air outlet channel 22 can carry away the residual moisture.

[0028] In another embodiment of this utility model, please refer to Figure 3 and Figure 4 Multiple air outlet channels 22 are provided, and the internal corners of multiple air outlet channels 22 are all rounded. The rounded corner structure can reduce airflow resistance and solve the problem of increased vortex and turbulence caused by right-angle structure.

[0029] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A micro-channel flow channel bipolar plate structure comprising an anode flow field plate (4), a proton exchange membrane (7) and a cathode flow field plate (8), characterized in that: The cathode flow field plate (8) includes a flow field plate one (1), a flow field plate two (2) and a diaphragm (3). The flow field plate one (1) has an air inlet (11) and an air inlet channel (12) inside. The flow field plate two (2) has an air outlet (21) and an air outlet channel (22) inside. The diaphragm (3) has a through hole (31). The air inlet channel (12) and the air outlet channel (22) are connected through the through hole (31).

2. A bipolar plate structure for a microchannel flow field according to claim 1, wherein: The anode flow field plate (4) and the cathode flow field plate (8) have the same structure. The proton exchange membrane (7) is fixedly provided with a cathode diffusion layer (5) on the side near the cathode flow field plate (8), and the proton exchange membrane (7) is fixedly provided with an anode diffusion layer (6) on the side near the anode flow field plate (4).

3. A bipolar plate structure for a microchannel flow field according to claim 1, wherein: The air inlet (11) is connected to the air inlet channel (12), and the air outlet (21) is connected to the air outlet channel (22).

4. A bipolar plate structure for a microchannel flow field according to claim 1, wherein: The air intake channel (12) is provided in multiple ways, and the opening diameter of the multiple air intake channels (12) near the air intake port (11) is larger than the opening diameter of the other end.

5. A bipolar plate structure for a microchannel flow field according to claim 1, wherein: The air outlet channel (22) is provided in multiple ways, and the internal corners of the multiple air outlet channels (22) are all rounded.

6. A bipolar plate structure for a microchannel flow field according to claim 1, wherein: The air inlet (11) is located at the midpoint of the side of the flow field plate one (1) away from the flow field plate two (2), and the air outlet (21) is located at the midpoint of the side of the flow field plate two (2) away from the flow field plate one (1).

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