Bipolar plate structure of high-power electric pile and fuel cell

Abstract

The utility model relates to a high-power electric pile bipolar plate structure and a fuel cell, the high-power electric pile bipolar plate structure comprises a bipolar plate body, two sides of the bipolar plate body are respectively an anode surface and a cathode surface; a hydrogen inlet, a first air outlet, a second air outlet, a first water outlet and a second water outlet are formed in one side of the bipolar plate body; an air inlet, a first hydrogen outlet, a second hydrogen outlet, a first water inlet and a second water inlet are formed in the other side of the bipolar plate body; a first activation region is arranged in the middle of the anode surface; a first distribution region and a second distribution region are arranged on two sides of the first activation region; a second activation area is arranged in the middle of the cathode face, and a third distribution area and a fourth distribution area are arranged on the two sides of the second activation area. Gas can be uniformly distributed in the surface of the polar plate, the problem of gas short circuit caused by increase of the activation area is prevented, the gas distribution uniformity is improved, the in-plane power generation deviation of the polar plate is favorably reduced, and the service life of a galvanic pile is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen energy fuel cell technology, and in particular to a high-power stack bipolar plate structure and fuel cell. Background Technology

[0002] A hydrogen proton exchange membrane fuel cell stack is a device that converts the chemical energy of hydrogen into electrical energy. It features zero emissions, high conversion efficiency, and fast start-up. Proton exchange membrane fuel cell stacks have wide applications in automobiles, power plants, and other fields. The core of a hydrogen proton exchange membrane fuel cell stack is formed by stacking a certain number of bipolar plates and membrane electrode assemblies. The power output of the stack is determined by the number of stacked plates and the activation area of ​​the bipolar plates. For the same number of plates, a larger activation area results in higher power; conversely, for the same activation area, more stacked plates result in higher power. Currently, high-power fuel cell stacks are increasingly widely used in the market.

[0003] The existing bipolar plate structure has six inlets and outlets distributed on both sides of the short side of the bipolar plate, namely hydrogen inlet and outlet, air inlet and outlet, and cooling water inlet and outlet. The middle is the activation zone of the plate. Increasing the activation area of ​​the bipolar plate will extend the flow channel and lengthen the plate. Such a bipolar plate will cause a large deviation in power generation between the front half near the air inlet and the rear half near the air outlet during the reaction. Often, the gas concentration in the rear half is lower, the reaction is worse, and the life of the stack is affected. If the plate is made wider, it is more difficult to control the uniformity of gas distribution on the plate. Often, the gas distribution in the flow channel far from the air inlet will be worse, which will lead to a larger deviation in the in-plane power generation of the plate. Utility Model Content

[0004] Therefore, the technical problem to be solved by this utility model is to overcome the defects of the existing high-power bipolar plate structure, which has uneven gas distribution due to the increased number of flow channels, large power generation deviation, and poor stack operation stability.

[0005] To solve the above-mentioned technical problems, this utility model provides a high-power fuel cell stack bipolar plate structure, including: a bipolar plate body, with an anode surface and a cathode surface on both sides of the bipolar plate body; a hydrogen inlet is provided in the middle of the bipolar plate body near one short side, and a first air outlet and a second air outlet are symmetrically arranged on both sides of the hydrogen inlet; an air inlet is provided in the middle of the bipolar plate body near the other short side, and a first hydrogen outlet and a second hydrogen outlet are symmetrically arranged on both sides of the air inlet; a first water outlet is provided between the hydrogen inlet and the first air outlet, and a second water outlet is provided between the hydrogen inlet and the second air outlet; a first water inlet is provided between the air inlet and the first hydrogen outlet, and a second water inlet is provided between the air inlet and the second hydrogen outlet; the first water inlet and the first water outlet communicate through the bipolar plate body, and the second water inlet and the second water outlet communicate through the bipolar plate body.

[0006] A first activation zone is provided in the middle of the anode surface, a first distribution zone is provided between the first activation zone and the hydrogen inlet, and a second distribution zone is provided between the first activation zone and the first hydrogen outlet and the second hydrogen outlet respectively.

[0007] A second activation zone is provided in the middle of the cathode surface, a third distribution zone is provided between the second activation zone and the air inlet, and a fourth distribution zone is provided between the second activation zone and the first air outlet and the second air outlet respectively.

[0008] In one embodiment of the present invention, the first activation zone includes a plurality of first flow channels arranged in parallel with each other, the first distribution zone includes a plurality of hydrogen inlet flow channels, the second distribution zone includes a plurality of hydrogen outlet flow channels, and the two ends of the first flow channels are respectively connected to the hydrogen inlet flow channels and the hydrogen outlet flow channels.

[0009] In one embodiment of this utility model, a first conical surface is provided on the side of the hydrogen inlet near the first distribution area, and a plurality of first air inlets are provided on the first conical surface, and the hydrogen inlet flow channel is connected to the first air inlets; a first inclined surface is provided on the side of the first hydrogen outlet and the second hydrogen outlet near the second distribution area, and a plurality of first air outlets are provided on the first inclined surface, and the air outlet flow channel is connected to the first air outlets.

[0010] In one embodiment of the present invention, the second activation zone includes a plurality of second flow channels arranged in parallel with each other, the third distribution zone includes a plurality of air inlet flow channels, the fourth distribution zone includes a plurality of air outlet flow channels, and the two ends of the second flow channel are respectively connected to the air inlet flow channel and the air outlet flow channel.

[0011] In one embodiment of this utility model, a second conical surface is provided on the side of the air inlet near the third distribution area, and a plurality of second air inlets are provided on the second conical surface, and the air inlet channel is connected to the second air inlets; a second inclined surface is provided on the side of the first air outlet and the second air outlet near the fourth distribution area, and a plurality of second air outlets are provided on the second inclined surface, and the air outlet channel is connected to the second air outlets.

[0012] In one embodiment of this utility model, a plurality of parallel flow channels are arranged inside the bipolar plate body along the length axis. The first water inlet and the first water outlet are connected through the parallel flow channels, and the second water inlet and the second water outlet are also connected through the parallel flow channels.

[0013] In one embodiment of this utility model, the first hydrogen outlet and the second hydrogen outlet have the same shape and size, and the area of ​​the hydrogen inlet is twice the area of ​​the first hydrogen outlet and the area of ​​the second hydrogen outlet.

[0014] In one embodiment of this utility model, the first air outlet and the second air outlet have the same shape and size, and the area of ​​the air inlet is twice the area of ​​the first air outlet and the area of ​​the second air outlet.

[0015] In one embodiment of this invention, the area of ​​the air inlet is larger than the area of ​​the hydrogen inlet.

[0016] A fuel cell includes the aforementioned high-power stack bipolar plate structure.

[0017] The above-mentioned technical solution of this utility model has the following advantages compared with the prior art:

[0018] This invention discloses a high-power bipolar plate structure for a fuel cell. The bipolar plate structure of this invention increases in width, thereby increasing the number of flow channels and manifolds. The hydrogen inlet is in the middle, and the hydrogen outlets are located on both sides, ensuring hydrogen flow to both sides and reducing the hydrogen flow path. Similarly, the air inlet is in the middle, and the air outlets are located on both sides, ensuring air flow to both sides and reducing the air flow path, which helps reduce air pressure drop. Each gas flow channel has an equal distance from inlet to outlet, allowing for uniform gas distribution within the plate surface. This prevents gas short-circuiting caused by increased activation area, improves gas distribution uniformity, reduces in-plane power generation deviation, and extends the fuel cell stack lifespan. Furthermore, each of the two water inlets is responsible for cooling half of the plate, promoting uniform plate cooling. Attached Figure Description

[0019] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the structure of the anode surface of the bipolar plate body in this utility model;

[0021] Figure 2 This is a schematic diagram of the structure of the cathode surface of the bipolar plate body in this utility model;

[0022] Figure 3 This is a schematic diagram of the flow direction of each fluid in this utility model;

[0023] Figure 4 This is a schematic diagram of uniform gas distribution in this utility model;

[0024] Figure 5 This is a cross-sectional view of the internal structure of the bipolar plate body in this utility model;

[0025] Explanation of reference numerals in the accompanying drawings: 1. Bipolar plate body; 2. Anode surface; 3. Cathode surface; 21. Hydrogen inlet; 22. First hydrogen outlet; 23. Second hydrogen outlet; 24. First activation zone; 25. First distribution zone; 26. Second distribution zone; 31. Air inlet; 32. First air outlet; 33. Second air outlet; 34. Second activation zone; 35. Third distribution zone; 36. Fourth distribution zone; 41. First water inlet; 42. Second water inlet; 43. ... 44. First outlet; 45. Second outlet; 211. Parallel flow channel; 212. First conical surface; 221. First air inlet; 222. First air outlet; 241. First flow channel; 251. Hydrogen inlet flow channel; 261. Hydrogen outlet flow channel; 311. Second conical surface; 312. Second air inlet; 321. Second inclined surface; 322. Second air outlet; 341. Second flow channel; 351. Air inlet flow channel; 361. Air outlet flow channel. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention. Example 1

[0027] Reference Figures 1-4As shown, this utility model discloses a high-power fuel cell stack bipolar plate structure, including: a bipolar plate body 1, with an anode surface 2 and a cathode surface 3 on both sides of the bipolar plate body 1; a hydrogen inlet 21 is provided in the middle of the bipolar plate body 1 near one of its shorter sides, and a first air outlet 32 ​​and a second air outlet 33 are symmetrically arranged on both sides of the hydrogen inlet 21; an air inlet 31 is provided in the middle of the bipolar plate body 1 near the other shorter side, and a first hydrogen outlet 22 and a second hydrogen outlet 23 are symmetrically arranged on both sides of the air inlet 31. A first water outlet 43 is provided between the hydrogen inlet 21 and the first air outlet 32, and a second water outlet 44 is provided between the hydrogen inlet 21 and the second air outlet 33; a first water inlet 41 is provided between the air inlet 31 and the first hydrogen outlet 22, and a second water inlet 42 is provided between the air inlet 31 and the second hydrogen outlet 23; the first water inlet 41 and the first water outlet 43 are connected through the bipolar plate body 1, and the second water inlet 42 and the second water outlet 44 are connected through the bipolar plate body 1.

[0028] A first activation zone 24 is provided in the middle of the anode surface 2. A first distribution zone 25 is provided between the first activation zone 24 and the hydrogen inlet 21. A second distribution zone 26 is provided between the first activation zone 24 and the first hydrogen outlet 22 and the second hydrogen outlet 23, respectively.

[0029] A second activation zone 34 is provided in the middle of the cathode surface 3. A third distribution zone 35 is provided between the second activation zone 34 and the air inlet 31. A fourth distribution zone 36 is provided between the second activation zone 34 and the first air outlet 32 ​​and the second air outlet 33, respectively.

[0030] The bipolar plate structure of this invention features five manifolds on each side of its short side. The hydrogen inlet 21 and air inlet 31 are located in the middle of the bipolar plate body 1. The two outermost manifolds on the side closest to the air inlet 31 are the first hydrogen outlet 22 and the second hydrogen outlet 23, respectively. The two outermost manifolds on the other side are the first air outlet 32 ​​and the second air outlet 33, respectively. A first water inlet 41 and a second water inlet 42 are respectively located between the air inlet 31 and the two hydrogen outlets. Conversely, a first water outlet 43 and a second water outlet 44 are located between the hydrogen inlet 21 and the two air outlets on the other side. Specifically, this invention expands the width of the bipolar plate body 1 and extends the number of manifolds. One hydrogen inlet 21 corresponds to two hydrogen outlets, and one air inlet 31 corresponds to two air outlets. The hydrogen inlet 21 and hydrogen outlets are not on the same side, and the two hydrogen outlets are equidistant from the hydrogen inlet 21 in both the x and y directions. Similarly, the air inlet 31 and air outlets are not on the same side, and the two air outlets are equidistant from the air inlet 31 in both the x and y directions. The first water inlet 41 and the first water outlet 43 are connected throughout the entire bipolar plate body 1, and the second water inlet 42 and the second water outlet 44 are connected throughout the entire bipolar plate body 1, used to introduce cooling water to cool the bipolar plate body 1.

[0031] One side of the bipolar plate body 1 is the anode surface 2, and the other side is the cathode surface 3. The anode surface 2 is the hydrogen activation surface, and the first activation region 24 connects the first distribution region 25 and the second distribution region 26 to realize the connection between the hydrogen inlet 21 and the first hydrogen outlet 22 and the second hydrogen outlet 23. The cathode surface 3 is the air activation surface, and the second activation region 34 connects the third distribution region 35 and the fourth distribution region 36 to realize the connection between the air inlet 31 and the first air outlet 32 ​​and the second air outlet 33.

[0032] The bipolar plate structure in this invention increases the width, thereby increasing the number of flow channels and manifolds. The hydrogen inlet 21 is in the middle, and the hydrogen outlets are located on both sides, ensuring hydrogen flows to both sides and reducing the hydrogen flow path. Similarly, the air inlet 31 is in the middle, and the air outlets are located on both sides, ensuring air flows to both sides and reducing the air flow path, which helps reduce air pressure drop. Each gas flow channel has an equal distance from inlet to outlet, allowing the gas to be evenly distributed within the plate surface. This prevents gas short-circuiting caused by the increased activation area, improves gas distribution uniformity, and helps reduce in-plane power generation deviation of the plate, thus extending the stack lifespan. Furthermore, the two cooling water inlets and outlets each handle half of the plate's cooling, promoting uniform plate cooling.

[0033] Furthermore, the first activation zone 24 includes a plurality of parallel first flow channels 241, the first distribution zone 25 includes a plurality of hydrogen inlet flow channels 251, and the second distribution zone 26 includes a plurality of hydrogen outlet flow channels 261. The two ends of the first flow channels 241 are respectively connected to the hydrogen inlet flow channels 251 and the hydrogen outlet flow channels 261. The hydrogen inlet 21 is provided with a first conical surface 211 on the side near the first distribution zone 25. A plurality of first air inlets 212 are provided on the first conical surface 211, and the hydrogen inlet flow channels 251 are connected to the first air inlets 212. The first hydrogen outlet 22 and the second hydrogen outlet 23 are both provided with a first inclined surface 221 on the side near the second distribution zone 26. A plurality of first air outlets 222 are provided on the first inclined surface 221, and the air outlet flow channels are connected to the first air outlets 222.

[0034] Specifically, both the first distribution zone 25 and the second distribution zone 26 are for distributing hydrogen gas, allowing the hydrogen gas to flow through the gas channels. The multiple hydrogen gas inlet channels 251 in the first distribution zone 25 can evenly distribute the hydrogen gas to the multiple activated first channels 241 on both sides. The second distribution zone 26 can guide the airflow from the multiple first channels 241 to the first hydrogen outlet 22 and the second hydrogen outlet 23. As a preferred embodiment of this utility model, the sidewall of the hydrogen inlet 21 protrudes towards one side of the first distribution zone 25 to form a first conical surface 211. Multiple first air inlets 212 are provided on the first conical surface 211. On the one hand, this facilitates the distribution of airflow to both sides. On the other hand, the conical surface design can increase the number of first air inlets 212 to meet the number of hydrogen gas inlet channels 251. Secondly, the sidewalls of the first hydrogen outlet 22 and the second hydrogen outlet 23 form a first inclined surface 221, and a first outlet hole 222 is opened on the first inclined surface 221. Preferably, the two first inclined surfaces 221 are designed to be parallel to the two sides of the first conical surface 211, so that the distance from each first inlet hole 212 to the first outlet hole 222 is equal.

[0035] Furthermore, the second activation zone 34 includes a plurality of parallel second flow channels 341, the third distribution zone 35 includes a plurality of air inlet flow channels 351, and the fourth distribution zone 36 includes a plurality of air outlet flow channels 361. The two ends of the second flow channel 341 are respectively connected to the air inlet flow channel 351 and the air outlet flow channel 361. The air inlet 31 is provided with a second conical surface 311 on the side near the third distribution zone 35. A plurality of second air inlets 312 are provided on the second conical surface 311. The air inlet flow channel 351 is connected to the second air inlets 312. The first air outlet 32 ​​and the second air outlet 33 are both provided with a second inclined surface 321 on the side near the fourth distribution zone 36. A plurality of second air outlets 322 are provided on the second inclined surface 321. The air outlet flow channel is connected to the second air outlets 322.

[0036] Similarly, the air activation surface of the cathode surface 3 has the same structural principle as the hydrogen activation surface of the anode surface 2, and will not be described in detail here.

[0037] Furthermore, the bipolar plate body 1 has multiple parallel flow channels 45 arranged inside along the length axis. The first water inlet 41 and the first water outlet 43 are connected through the parallel flow channels 45, and the second water inlet 42 and the second water outlet 44 are also connected through the parallel flow channels 45.

[0038] Specifically, multiple parallel flow channels 45 are arranged along the length axis of the bipolar plate body 1. The multiple parallel flow channels 45 are used to connect the inlet and outlet on both sides. Cooling water is input from the first inlet 41 and the second inlet 42, and after passing through the parallel flow channels 45, it is output from the first outlet 43 and the second outlet 44 to cool the bipolar plate body 1.

[0039] Furthermore, the first hydrogen outlet 22 and the second hydrogen outlet 23 have the same shape and size, and the area of ​​the hydrogen inlet 21 is twice the area of ​​the first hydrogen outlet 22 and the second hydrogen outlet 23.

[0040] Specifically, hydrogen is input through hydrogen inlet 21 and output through splitting into first hydrogen outlet 22 and second hydrogen outlet 23. To ensure that the output of first hydrogen outlet 22 and second hydrogen outlet 23 is consistent, the shapes and sizes of first hydrogen outlet 22 and second hydrogen outlet 23 are consistent. At the same time, to control the flow rate of hydrogen, the area of ​​hydrogen inlet 21 is twice the area of ​​first hydrogen outlet 22 and second hydrogen outlet 23.

[0041] Similarly, the first air outlet 32 ​​and the second air outlet 33 have the same shape and size, and the area of ​​the air inlet 31 is twice the area of ​​the first air outlet 32 ​​and the second air outlet 33.

[0042] Furthermore, according to the requirements of the chemical reaction, hydrogen and oxygen undergo an electrochemical reaction to produce water. From the chemical reaction formula 2H₂ + O₂ = 2H₂O, it can be seen that the stoichiometric ratio of hydrogen to oxygen is 2:1. The volume fraction of oxygen in the air is approximately 21%, which means that a large amount of air is needed to provide sufficient oxygen for a reaction with a certain amount of hydrogen. Therefore, to meet the stoichiometric ratio requirements of the reaction, a larger air inlet 31 is needed to ensure sufficient oxygen participates in the reaction. Therefore, the area of ​​the air inlet 31 is larger than the area of ​​the hydrogen inlet 21. Example 2

[0043] A fuel cell includes the high-power stack bipolar plate structure described in Example 1.

[0044] In summary, this invention introduces a high-power bipolar plate structure for a fuel cell stack. The bipolar plate structure of this invention increases the width, thereby increasing the number of flow channels and manifolds. The hydrogen inlet 21 is located in the middle, and the hydrogen outlets are located on both sides, ensuring hydrogen flow to both sides and reducing the hydrogen flow path. Similarly, the air inlet 31 is located in the middle, and the air outlets are located on both sides, ensuring air flow to both sides and reducing the air flow path, which helps reduce air pressure drop. Each gas flow channel has an equal distance from inlet to outlet, allowing the gas to be evenly distributed within the plate surface. This prevents gas short-circuiting caused by the increased activation area, improves gas distribution uniformity, and helps reduce in-plane power generation deviation of the plate, thus extending the stack lifespan. Furthermore, the two water inlets each handle half of the plate's cooling, promoting uniform plate cooling.

[0045] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A high-power fuel cell stack bipolar plate structure, characterized in that, include: A bipolar plate body has an anode surface and a cathode surface on its two sides, respectively. A hydrogen inlet is located in the middle of one short side of the bipolar plate body, with a first air outlet and a second air outlet symmetrically arranged on either side of the hydrogen inlet. An air inlet is located in the middle of the other short side of the bipolar plate body, with a first hydrogen outlet and a second hydrogen outlet symmetrically arranged on either side of the air inlet. A first water outlet is located between the hydrogen inlet and the first air outlet, and a second water outlet is located between the hydrogen inlet and the second air outlet. A first water inlet is located between the air inlet and the first hydrogen outlet, and a second water inlet is located between the air inlet and the second hydrogen outlet. The first water inlet and the first water outlet communicate through the bipolar plate body, and the second water inlet and the second water outlet communicate through the bipolar plate body. A first activation zone is provided in the middle of the anode surface, a first distribution zone is provided between the first activation zone and the hydrogen inlet, and a second distribution zone is provided between the first activation zone and the first hydrogen outlet and the second hydrogen outlet respectively. A second activation zone is provided in the middle of the cathode surface, a third distribution zone is provided between the second activation zone and the air inlet, and a fourth distribution zone is provided between the second activation zone and the first air outlet and the second air outlet respectively.

2. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The first activation zone includes multiple parallel first flow channels, the first distribution zone includes multiple hydrogen inlet flow channels, and the second distribution zone includes multiple hydrogen outlet flow channels. The two ends of the first flow channels are respectively connected to the hydrogen inlet flow channels and the hydrogen outlet flow channels.

3. The high-power fuel cell stack bipolar plate structure according to claim 2, characterized in that: The hydrogen inlet has a first conical surface on the side near the first distribution area, and a plurality of first air inlets are provided on the first conical surface. The hydrogen inlet flow channel is connected to the first air inlets. The first hydrogen outlet and the second hydrogen outlet both have a first inclined surface on the side near the second distribution area, and a plurality of first air outlets are provided on the first inclined surface. The air outlet flow channel is connected to the first air outlets.

4. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The second activation zone includes multiple parallel second flow channels, the third distribution zone includes multiple air inlet flow channels, and the fourth distribution zone includes multiple air outlet flow channels. The two ends of the second flow channel are respectively connected to the air inlet flow channel and the air outlet flow channel.

5. The high-power fuel cell stack bipolar plate structure according to claim 4, characterized in that: The air inlet is provided with a second conical surface on the side near the third distribution area, and a plurality of second air inlets are provided on the second conical surface. The air inlet channel is connected to the second air inlets. The first air outlet and the second air outlet are both provided with a second inclined surface on the side near the fourth distribution area. A plurality of second air outlets are provided on the second inclined surface, and the air outlet channel is connected to the second air outlets.

6. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The bipolar plate body has multiple parallel flow channels arranged along its length axis inside. The first water inlet and the first water outlet are connected through the parallel flow channels, and the second water inlet and the second water outlet are also connected through the parallel flow channels.

7. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The first hydrogen outlet and the second hydrogen outlet have the same shape and size, and the area of ​​the hydrogen inlet is twice the area of ​​the first hydrogen outlet and the second hydrogen outlet.

8. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The first air outlet and the second air outlet have the same shape and size, and the area of ​​the air inlet is twice the area of ​​the first air outlet and the second air outlet.

9. The high-power fuel cell stack bipolar plate structure according to claim 1, characterized in that: The area of ​​the air inlet is larger than the area of ​​the hydrogen inlet.

10. A fuel cell, characterized in that, Including the high-power fuel cell stack bipolar plate structure as described in any one of claims 1-9.

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