A fuel cell bipolar plate

Abstract

The utility model relates to fuel cell technical field, concretely provides a kind of fuel cell bipolar plate.The fuel cell bipolar plate includes: anode surface and cathode surface, wherein: the cathode surface is equipped with multiple open air straight flow channel;And, in each open air straight flow channel, the bottom surface of at least one open air straight flow channel is high-low undulating bottom along air flow direction;The anode surface is equipped with hydrogen gas access and multiple hydrogen gas bending flow channel communicated with the hydrogen gas access.In this way, since the cathode surface of the fuel cell bipolar plate in each open air straight flow channel, the bottom surface of at least one open air straight flow channel is high-low undulating bottom along air flow direction, air can produce a speed component in the process of flowing in the open air straight flow channel towards membrane electrode direction, and then air can better penetrate into the gas diffusion layer of membrane electrode, thereby solve the problem in the prior art.

Description

Technical Field

[0001] This utility model relates to the field of fuel cell technology, specifically to a fuel cell bipolar plate. Background Technology

[0002] Fuel cells, especially proton exchange membrane fuel cells (PEMFCs), have been widely used in applications such as fuel cell electric vehicles and fuel cell backup power supplies due to their advantages of being pollution-free, having high specific energy, low noise, and high energy conversion efficiency.

[0003] Based on their cooling methods, fuel cells are mainly divided into air-cooled fuel cells and water-cooled fuel cells. Water-cooled fuel cells primarily use a cooling subsystem and cooling water within this subsystem to regulate the stack temperature. This method is more suitable for applications with relatively high power, such as vehicles. However, for low-power applications such as two-wheeled vehicles, drones, and small robots, the equipment mounted on water-cooled fuel cells is complex, making it uneconomical. In contrast, air-cooled fuel cells, which use fan airflow for cooling, have a simpler structure and offer better application prospects for low-power applications compared to the more complex water-cooled fuel cells.

[0004] Based on the way they come into contact with air, air-cooled fuel cells can be further divided into two types: open-cathode air-cooled fuel cells and closed-cathode air-cooled fuel cells. In the open-cathode air-cooled fuel cell, the cathode is in direct contact with the air in the environment. In this case, the air is both a reactant (oxygen in the air acts as an oxidant) and a coolant to remove the heat generated by the reaction, thus achieving a cooling effect.

[0005] like Figure 1 The diagram shows a schematic of the specific structure of a current open-cathode air-cooled fuel cell. The open-cathode air-cooled fuel cell includes a bipolar plate 10 and a membrane electrode 20, which are stacked and press-fitted in sequence to obtain the open-cathode air-cooled fuel cell.

[0006] In practical applications, the membrane electrode 20 is typically composed of a proton exchange membrane, a gas diffusion layer, and catalyst particles. The bipolar plate 10 has multiple air channels 101, which can be used, for example, by blowing air through a fan, to allow air to flow in the air channels 101 and then permeate into the membrane electrode 20 to react with hydrogen.

[0007] However, in the current open-cathode air-cooled fuel cell, the bipolar plate 10 air channel is prone to problems where air cannot penetrate into the membrane electrode, affecting the output performance of the open-cathode air-cooled fuel cell. Utility Model Content

[0008] In view of the deficiencies in the existing technology, the purpose of this utility model is to provide a fuel cell bipolar plate, which aims to solve the technical problems in the related technology to a certain extent.

[0009] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0010] This application provides a fuel cell bipolar plate, characterized in that it includes an anode surface and a cathode surface, wherein:

[0011] The cathode surface is provided with multiple open air direct current channels; and, in each of the open air direct current channels, the bottom surface of at least one open air direct current channel is undulating along the air flow direction.

[0012] The anode surface is provided with a hydrogen inlet and outlet and multiple hydrogen bend channels connected to the hydrogen inlet and outlet.

[0013] Preferably, the edge of the anode surface is provided with an anode annular sealing groove.

[0014] Preferably, the corners of the anode annular sealing ring groove are rounded.

[0015] Preferably, the fuel cell bipolar plate is also provided with a temperature sensor socket.

[0016] Preferably, the end of the cathode surface is provided with a cathode end sealing ring groove.

[0017] Preferably, the cathode end sealing groove includes a first sealing groove corresponding to the hydrogen inlet / outlet position, and a second sealing groove at other positions on the cathode end.

[0018] Preferably, the corners of the first sealing ring groove and the second sealing ring groove are rounded.

[0019] Preferably, the hydrogen bend channel is wavy along the hydrogen flow direction.

[0020] Preferably, the anode surface is provided with a plurality of DC channel sidewalls; and a wavy side ridge is provided between adjacent DC channel sidewalls to form the plurality of hydrogen bend channels.

[0021] Preferably, in the plurality of open air direct current channels, at least one open air direct current channel has a crossflow port on its side wall.

[0022] Based on the above technical solution, the advantages of this utility model compared with the prior art are as follows:

[0023] The fuel cell bipolar plate provided in this application includes an anode surface and a cathode surface. The cathode surface has multiple open air channels, and at least one of the open air channels has an undulating bottom surface along the airflow direction. The anode surface has a hydrogen inlet / outlet and multiple hydrogen bend channels connected to the hydrogen inlet / outlet. Because at least one open air channel on the cathode surface of this fuel cell bipolar plate has an undulating bottom surface along the airflow direction, air flowing within these open air channels generates a velocity component in the direction towards the membrane electrode assembly (MEA). This allows the air to better penetrate the gas diffusion layer of the MEA, thus solving the problems in the prior art. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the specific structure of an open-cathode air-cooled fuel cell in the prior art.

[0025] Figure 2 This is a schematic diagram of the structure of the anode surface of a fuel cell bipolar plate, provided for an embodiment of this application.

[0026] Figure 3 This is a schematic diagram of the structure of the cathode surface of a fuel cell bipolar plate, provided for an embodiment of this application.

[0027] Figure 4 This is a schematic cross-sectional view of an open air direct current channel in the cathode surface of a fuel cell bipolar plate, provided for an embodiment of this application.

[0028] In the above schematic diagram: 10-bipolar plate; 20-membrane electrode; 101-air flow channel; 1-anode surface; 11-hydrogen inlet / outlet; 12-hydrogen bend flow channel; 13-anode annular sealing ring groove; 14-direct flow channel sidewall; 15-wavy side ridge; 2-cathode surface; 21-open direct air flow channel; 211-undulating bottom; 22-sidewall; 23-flow port; 24-cathode end sealing ring groove; 241-first sealing ring groove; 242-second sealing ring groove; 3-temperature sensor socket. Detailed Implementation

[0029] The embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0030] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0031] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover a 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 said element.

[0032] As mentioned earlier, in the current open-cathode air-cooled fuel cell, the bipolar plate 10 air channel is prone to problems where air cannot penetrate into the membrane electrode, affecting the output performance of the open-cathode air-cooled fuel cell.

[0033] In view of this, embodiments of this application provide a fuel cell bipolar plate that can solve this technical problem. For example... Figure 2 The diagram shown is a schematic diagram of the specific structure of a fuel cell bipolar plate provided in the embodiment of this application. The fuel cell bipolar plate includes an anode surface 1 and a cathode surface 2. The anode surface 1 is used to carry the flow of anode gas (i.e., hydrogen gas), and the cathode surface 2 is used to carry the flow of cathode gas (i.e., air gas).

[0034] Here we can first describe the structure of the anode surface 1 of the bipolar plate of the fuel cell. The anode surface 1 is provided with a hydrogen inlet / outlet 11 and a plurality of hydrogen bend channels 12, and the plurality of hydrogen bend channels 12 are connected to the hydrogen inlet / outlet 11.

[0035] For example, hydrogen inlet and outlet 11 can be set at both ends of the anode surface 1, and one (any one) hydrogen inlet and outlet 11 can be used as the hydrogen inlet and the other hydrogen inlet and outlet 11 can be used as the hydrogen outlet. In this way, hydrogen can flow into the bipolar plate of the fuel cell from the hydrogen inlet, and then flow into the hydrogen outlet through multiple hydrogen bend channels 12, and then flow out from the hydrogen outlet, thereby forming a hydrogen cycle.

[0036] In practical applications, the reason why the hydrogen on the anode surface 1 is set as a hydrogen bend channel 12 (that is, a bend-shaped channel) is to increase the area ratio of the channel, thereby increasing the contact area between the hydrogen in the channel and the membrane electrode and improving the reaction activity.

[0037] The hydrogen flow channel 12 can be wavy along the hydrogen flow direction. Because the wavy surface has a certain curvature, it provides a vertical motion component during the forward flow of hydrogen. The anode surface 1 can have multiple direct-flow sidewalls 14, and adjacent direct-flow sidewalls 14 can be separated by wavy side ridges 15, thus forming the multiple hydrogen flow channels 12.

[0038] In addition, the cathode surface 2 of the fuel cell bipolar plate is provided with multiple open air direct flow channels 21. The reason why the air flow channel on the cathode surface 2 is designed as a direct flow channel (that is, a straight channel running from one side of the bipolar plate to the other side) is to increase the air flow. For example, when the fan is blowing air, this direct flow channel can reduce wind resistance and make the air flow more easily.

[0039] It is important to note that among the multiple open air channels 21 on the cathode surface 2, at least one open air channel 21 has an undulating bottom surface 211 along the airflow direction. For example, the bottom surface of each or part of the open air channels 21 may have an undulating bottom surface 211 along the airflow direction. In this way, when air flows within the open air channel 21, the undulating bottom surface 211 allows the air to generate a velocity component in the direction of the membrane electrode, thereby enabling the air to better enter the gas diffusion layer of the membrane electrode.

[0040] In practical applications, the undulating bottom 211 can be a wave-shaped structure, a broken line shape, or other undulating bottoms.

[0041] The fuel cell bipolar plate provided in this application includes an anode surface 1 and a cathode surface 2. The cathode surface 2 is provided with multiple open air direct current channels 21, and at least one of the open air direct current channels 21 has an undulating bottom surface along the air flow direction. The anode surface 1 is provided with a hydrogen inlet / outlet 11 and multiple hydrogen bend channels 12 communicating with the hydrogen inlet / outlet 11. Because at least one of the open air direct current channels 21 on the cathode surface 2 of this fuel cell bipolar plate has an undulating bottom surface along the air flow direction, air flowing within the open air direct current channel 21 can generate a velocity component in the direction towards the membrane electrode assembly (MEA). This allows the air to better penetrate into the gas diffusion layer of the MEA, thereby solving the problems in the prior art and improving the output performance of the open-cathode air-cooled fuel cell.

[0042] It should be further explained that during the process of blowing air towards the cathode open-type air-cooled fuel cell by a fan, the air inside each open air direct channel 21 on the cathode surface 2 of the fuel cell bipolar plate will flow along the open air direct channel 21. However, in actual applications, the air flow velocity in each open air direct channel 21 will be different. For example, the open air direct channel 21 facing the fan will have a relatively higher air pressure and a relatively faster air flow velocity inside it. This can easily lead to significant differences in the performance of different areas of the fuel cell.

[0043] Therefore, in the plurality of open air direct current channels 21 provided in this application embodiment, at least one open air direct current channel 21 has a crossflow port 23 on its sidewall 22. Through this crossflow port 23, the open air direct current channels 21 on both sides of the crossflow port 23 can be connected. Thus, when the air velocity in one open air direct current channel 21 is high, it can flow into the other open air direct current channel 21, thereby improving the performance consistency of various regions of the fuel cell. For example, in practical applications, the crossflow port 23 can be provided on the sidewall 22 of each open air direct current channel 21, thereby connecting these open air direct current channels 21 and further improving the performance consistency of various regions of the fuel cell.

[0044] In practical applications, it is usually necessary to seal the cathode and anode of a fuel cell separately. Therefore, for the fuel cell bipolar plate provided in this embodiment, an anode annular sealing groove 13 is provided on the edge of its anode surface 1, so that a corresponding annular sealing ring can be arranged in the anode annular sealing groove 13. In this way, after assembling into a cathode-open air-cooled fuel cell, the anode gas (i.e., hydrogen) can be sealed through the annular sealing ring. In practical applications, the corners of the anode annular sealing groove 13 can be rounded to facilitate the arrangement of the annular sealing ring.

[0045] The cathode surface 2 of the fuel cell bipolar plate is provided with a cathode end sealing ring groove 24 at its end. For example, the cathode surface 2 is provided with a cathode end sealing ring groove 24 at each of its two ends, thereby sealing the cathode surface 2.

[0046] The cathode end sealing groove 24 may further include a first sealing groove 241 corresponding to the hydrogen inlet / outlet 11, and a second sealing groove 242 at other positions on the cathode surface 2. The first sealing groove 241 corresponds to the hydrogen inlet / outlet 11 on the anode surface 1, and a first sealing groove 241 can be used to prevent gas cross-flow between the anode surface 1 and the cathode surface. The second sealing groove 242 is located at other positions on the cathode surface 2, and a second sealing groove 242 can be used to further seal the cathode surface 2. Of course, the corners of both the first sealing groove 241 and the second sealing groove 242 can be rounded.

[0047] In practical applications, when the cathode is an open-type air-cooled fuel cell, it is usually necessary to monitor its temperature. Therefore, the bipolar plate of the fuel cell can be further provided with a temperature sensor socket 3, so that a temperature sensor can be installed in the temperature sensor socket 3 for temperature monitoring.

[0048] Based on the fuel cell bipolar plate provided in the embodiments of this application, the embodiments of this application can further provide a cathode open-type air-cooled fuel cell. Compared with the existing cathode open-type air-cooled fuel cells, the cathode open-type air-cooled fuel cell uses the fuel cell bipolar plate provided in the embodiments of this application. In this way, since at least one of the open air channels 21 on the cathode surface 2 of the fuel cell bipolar plate has an undulating bottom surface along the air flow direction, the air can generate a velocity component in the direction towards the membrane electrode during the flow of air in the open air channel 21. This allows the air to better penetrate into the gas diffusion layer of the membrane electrode, thereby solving the problems in the prior art and improving the output performance of the cathode open-type air-cooled fuel cell.

[0049] This utility model is not limited to the above-described embodiments. For those skilled in the art, various improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications are also considered to be within the protection scope of this utility model. Contents not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A fuel cell bipolar plate, characterized in that, It includes an anode surface (1) and a cathode surface (2), wherein: The cathode surface (2) is provided with a plurality of open air direct current channels (21); and, in each of the open air direct current channels (21), at least one of the open air direct current channels (21) has a bottom surface with undulating height along the air flow direction. The anode surface (1) is provided with a hydrogen inlet / outlet (11) and a plurality of hydrogen bend channels (12) connected to the hydrogen inlet / outlet (11).

2. The fuel cell bipolar plate according to claim 1, characterized in that, The edge of the anode surface (1) is provided with an anode annular sealing groove (13).

3. The fuel cell bipolar plate according to claim 2, characterized in that, The corners of the anode annular sealing groove (13) are rounded.

4. The fuel cell bipolar plate according to claim 1, characterized in that, The fuel cell bipolar plate is also provided with a temperature sensor socket (3).

5. The fuel cell bipolar plate according to claim 1, characterized in that, The cathode surface (2) is provided with a cathode end sealing ring groove (24) at its end.

6. The fuel cell bipolar plate according to claim 5, characterized in that, The cathode end sealing groove (24) includes a first sealing groove (241) corresponding to the position of the hydrogen inlet / outlet (11), and a second sealing groove (242) at other positions of the cathode surface (2).

7. The fuel cell bipolar plate according to claim 5, characterized in that, The corners of the first sealing ring groove (241) and the second sealing ring groove (242) are rounded.

8. The fuel cell bipolar plate according to claim 1, characterized in that, The hydrogen flow channel (12) is wavy and bends along the direction of hydrogen flow.

9. The fuel cell bipolar plate according to claim 8, characterized in that, The anode surface (1) is provided with a plurality of DC channel sidewalls (14); and a wavy side ridge (15) is provided between adjacent DC channel sidewalls (14) to form the plurality of hydrogen bend channels (12).

10. The fuel cell bipolar plate according to claim 1, characterized in that, In the plurality of open air direct current channels (21), at least one open air direct current channel (21) has a crossflow port (23) on its side wall (22).

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