Bipolar plate structure of high-power fuel cell

Abstract

The utility model discloses a bipolar plate structure of a high-power fuel cell. The bipolar plate structure comprises two inlet and outlet areas, two distribution areas and a reaction area, the inlet-outlet area is divided into an inlet area and an outlet area which are positioned on the left side and the right side of the bipolar plate; the left side of the bipolar plate comprises a first cooling liquid cavity, a second air outlet cavity, a hydrogen inlet cavity, a first air outlet cavity and another first cooling liquid cavity from top to bottom; the right side of the bipolar plate comprises a second cooling liquid cavity, a first hydrogen outlet cavity, an air inlet cavity, a second hydrogen outlet cavity and another third cooling liquid cavity from top to bottom; through the arrangement of the air flow guide assembly and the hydrogen flow guide assembly, for example, air is divided into two strands after reaching two air outlet cavities under the action of a flow channel, the two strands respectively flow out from the two air outlet cavities, and after a conventional bipolar plate with one inlet and one outlet is changed into a bipolar plate with one inlet and two outlets, the structures of the hydrogen flow guide assembly and the air flow guide assembly are the same; therefore, the air flow resistance can be greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of bipolar plates, in particular to a bipolar plate structure for high-power fuel cells. Background Art

[0002] The bipolar plates currently popular in the market are generally applied to the range of 100 - 150 kW fuel cell stacks. Very few can meet about 180 kW. The active area of the bipolar plate is about 300 - 350 cm 2 , for a single fuel cell stack above 200 kW, the active area of the bipolar plate needs to reach 400 cm 2 , and for a 300 kW single fuel cell stack, it even needs to reach 500 cm 2 or more. Currently, the bipolar plate structure is composed of three parts: an inlet and outlet area, a distribution area, and a reaction area. The inlet and outlet area is divided into six chambers: hydrogen inlet and outlet, air inlet and outlet, and cooling water inlet and outlet. The inlet and outlet are located on the left and right outer sides. Next is the distribution area, and the middle area is the reaction area, also known as the flow field area. This structure is the most common structure currently. The maximum active area of the reaction area is about 350 cm 2 or so, which can meet the requirements of a single fuel cell stack with a maximum power of about 150 kW.

[0003] It is commonly used in light vehicles such as buses and logistics vehicles. For the current heavy trucks, mining trucks and other heavy vehicle fields, it is slightly insufficient. Currently, manufacturers adopt a hybrid mode of small-power fuel cells and a certain amount of lithium batteries to meet the needs of heavy vehicles. Very few advanced manufacturers connect two 100 - 150 kW fuel cell stacks in series and adopt a dual fuel cell stack single system mode. For the first hybrid mode, it is not completely a hydrogen energy engine in essence. At the same time, the structure is complex, the failure rate is high, the maintenance cost is large, and it does not belong to the category of green energy. For the second dual fuel cell stack single system mode, although it solves the problems brought by hybridization to a certain extent, the dual fuel cell stack single system mode is prone to excessive loss of one of the fuel cell stacks during operation, accelerating the attenuation of the fuel cell stack and affecting the service life of the entire fuel cell system.

[0004] In the existing structure of fuel cell bipolar plates, it is a one-in-one-out structure of traditional air inlets and outlets. It is easy for the bipolar plate to be flooded due to the large reaction area, small outlet, and difficult gas exhaust and drainage, which affects the performance of the fuel cell stack. At the same time, the traditional operation mode of cooling water entering from one side, passing through the distribution area, entering the reaction area, and then coming out through the distribution area is also prone to uneven overall plate heat dissipation due to the large reaction area, affecting the performance of the fuel cell stack.

[0005] Therefore, in order to solve the above deficiencies, a bipolar plate structure for high-power fuel cells is proposed. Summary of the Invention

[0006] The utility model overcomes the deficiencies of the prior art and provides a bipolar plate structure for a high-power fuel cell.

[0007] To achieve the above object, the technical solution adopted by the utility model is: a bipolar plate structure for a high-power fuel cell, comprising two inlet and outlet areas, two distribution areas and a reaction area;

[0008] The inlet and outlet areas are divided into an inlet area and an outlet area, which are located in the left and right side areas of the bipolar plate. The left side of the bipolar plate includes, from top to bottom: a first coolant cavity, a second air outlet cavity, a hydrogen inlet cavity, a first air outlet cavity and another first coolant cavity; the right side of the bipolar plate includes, from top to bottom: a second coolant cavity, a first hydrogen outlet cavity, an air inlet cavity, a second hydrogen outlet cavity and another third coolant cavity;

[0009] The distribution areas are located inside the inlet and outlet areas and include: a coolant flow path, an air flow path and a hydrogen flow path; the coolant flow path, the air flow path and the hydrogen flow path connect the inlet and outlet areas and the reaction area, and the structures of the coolant flow path, the air flow path and the hydrogen flow path are all continuous strip-shaped channels;

[0010] The two first coolant cavities are arranged outside the left-side first air outlet cavity and the second air outlet cavity, presenting an up-and-down layout, and the two second coolant cavities are arranged outside the right-side first hydrogen outlet cavity and the second hydrogen outlet cavity, presenting an up-and-down layout.

[0011] In a preferred embodiment of the utility model, two third coolant cavities are provided on the bipolar plate, and the two third coolant cavities are located between the first coolant cavity and the second coolant cavity.

[0012] In a preferred embodiment of the utility model, the reaction area is located in the middle of the two side distribution areas, and the reaction area connects the two inlet and outlet areas.

[0013] In a preferred embodiment of the utility model, a number of ridges are provided in the reaction area, and a flow channel is provided between two adjacent ridges, and the flow channel is a channel for fluid.

[0014] In a preferred embodiment of the utility model, the shape of the ridge is serpentine and arranged in a periodic pattern, and the ridges are parallel.

[0015] In a preferred embodiment of the utility model, the cross-section of the ridge is rectangular, arc-shaped or trapezoidal, and the material of the bipolar plate is not limited to graphite or stainless steel metal plate.

[0016] In a preferred embodiment of the utility model, the internal structures of the first air outlet cavity, the hydrogen inlet cavity, the second air outlet cavity, the first coolant cavity, the second coolant cavity, the first hydrogen outlet cavity, the air inlet cavity and the second hydrogen outlet cavity are all the same reinforcing rib assemblies.

[0017] In a preferred embodiment of the present utility model, the reinforcing rib assembly includes a reaction cavity, a flow field groove arranged in the reaction cavity, two inlet / outlet reinforcing ribs arranged on one inner wall of the reaction cavity, a plurality of inlet pipes arranged on the outer wall of the reaction cavity, and a plurality of connecting reinforcing ribs arranged on one outer wall of the reaction cavity.

[0018] In a preferred embodiment of the present utility model, the flow field groove is opened in the reaction cavity. The two inlet / outlet reinforcing ribs are connected to one inner wall of the reaction cavity through pipelines, and the two inlet / outlet reinforcing ribs are communicated with the flow field groove.

[0019] In a preferred embodiment of the present utility model, the plurality of inlet pipes are respectively connected to the outer walls around the reaction cavity through pipelines, and one ends of the plurality of inlet pipes penetrate through the reaction cavity. The plurality of connecting reinforcing ribs are connected to one outer wall of the reaction cavity through pipelines, and the plurality of connecting reinforcing ribs are communicated with the flow field groove.

[0020] The present utility model solves the defects existing in the background technology and has the following beneficial effects:

[0021] (1) The present utility model provides a bipolar plate structure for a high-power fuel cell. Through the one-inlet-two-outlet structure of the hydrogen flow path and the air flow path, for example, air is divided into two streams after reaching two air outlet cavities under the action of the air flow path, and the two streams flow out from the two air outlet cavities respectively. After changing the conventional bipolar plate from one-inlet-one-outlet to one-inlet-two-outlet, the hydrogen gas guiding component and the air guiding component have the same structure, so that the air flow resistance will be greatly improved, and the drainage and exhaust capacity will be enhanced.

[0022] (2) The present utility model provides a bipolar plate structure for a high-power fuel cell. Through the structures of the first coolant cavity, the second coolant cavity and the third coolant cavity, two types of water inlet and outlet structures, namely, the vertical type and the cross type, are formed, significantly improving the heat dissipation efficiency and the performance of the fuel cell stack. In the vertical cooling structure, the coolant passes through the two upper first coolant regulating cavities and the second coolant regulating cavity and vertically flows to the corresponding two first coolant regulating cavities and the second coolant regulating cavity below, which can directly absorb heat and achieve rapid and uniform heat transfer. In the cross cooling structure, the coolant flows from the two left second coolant regulating cavities to the two second coolant regulating cavities in the horizontal position correspondingly. During this process, the two second coolant regulating cavities stop working, so that the coolant flows horizontally, forming a cross cooling path, increasing the contact area between the coolant and the reaction area in the bipolar plate, and further improving the heat exchange efficiency. Especially when facing a large-area reaction area, local overheating is effectively prevented.

[0023] (3) The present utility model provides a bipolar plate structure for a high-power fuel cell. Through the one-inlet-two-outlet structure of the hydrogen flow path and the air flow path, uniform and efficient gas distribution can be achieved. Uniform distribution helps to improve the chemical reaction efficiency of the fuel cell, thereby increasing the output power and overall performance of the battery. In addition, the optimized gas flow path reduces the dead zone of the gas inside the battery, helps to reduce energy loss, and further improves the energy conversion efficiency of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present utility model will be further described below in conjunction with the drawings and embodiments;

[0025] Figure 1 is a schematic diagram of the bipolar plate structure from the first perspective of the preferred embodiment of the present utility model;

[0026] Figure 2 is a schematic diagram of the bipolar plate structure from the first perspective of the preferred embodiment of the present utility model;

[0027] Figure 3 is a schematic diagram of the local structure of the water-hydrogen-air three-chamber of the preferred embodiment of the present utility model;

[0028] In the figure: 1. Inlet and outlet area; 2. Distribution area; 3. Reaction area; 11. First air outlet chamber; 12. Hydrogen inlet chamber; 13. Second air outlet chamber; 14. First coolant chamber; 15. Second coolant chamber; 16. First hydrogen outlet chamber; 17. Air inlet chamber; 18. Second hydrogen outlet chamber; 19. Third coolant chamber; 6. Reinforcement rib assembly; 61. Flow field groove; 62. Connecting reinforcement rib; 63. Inlet and outlet reinforcement rib; 64. Introduction pipe; 65. Reaction cavity; 100. Coolant flow path; 110. Hydrogen flow path; 120. Air flow path. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The present utility model will now be further described in detail in conjunction with the drawings and embodiments. These drawings are all simplified schematic diagrams, which only illustrate the basic structure of the present utility model in a schematic manner, so they only show the components related to the present utility model.

[0030] From Figure 1 the schematic diagram of the bipolar plate structure of Embodiment 1, it can be seen that a bipolar plate structure for a high-power fuel cell includes two inlet and outlet areas 1, two distribution areas 2, and a reaction area 3;

[0031] The import and export area 1 is divided into an import area and an export area, which are located in the left and right side areas of the bipolar plate. From top to bottom on the left side of the bipolar plate, there are: the first coolant cavity 14, the second air outlet cavity 13, the hydrogen inlet cavity 12, the first air outlet cavity 11, and another first coolant cavity 14; from top to bottom on the right side of the bipolar plate, there are: the second coolant cavity 15, the first hydrogen outlet cavity 16, the air inlet cavity 17, the second hydrogen outlet cavity 18, and another third coolant cavity 19;

[0032] The distribution area 2 is located inside the import and export area 1 and includes: the coolant flow path 100, the air flow path 120, and the hydrogen flow path 110; the coolant flow path 100, the air flow path 120, and the hydrogen flow path 110 connect the import and export area 1 and the reaction area 3, and the structures of the coolant flow path 100, the air flow path 120, and the hydrogen flow path 110 are all continuous strip-shaped channels;

[0033] The reaction area 3 is located between the two distribution areas 2 on both sides. The reaction area 3 is connected to the two import and export areas 1. There are several ridges in the reaction area 3. There is a flow channel between two adjacent ridges. The flow channel is a channel for fluid. The shape of the ridge is snake-shaped and arranged in a periodic pattern. The ridges are parallel. The cross-section of the ridge is rectangular, arc-shaped or trapezoidal. The material of the bipolar plate is not limited to graphite or stainless steel metal plate;

[0034] The two first coolant cavities 14 are arranged outside the first air outlet cavity 11 and the second air outlet cavity 13 on the left side, showing an up-and-down layout. The two second coolant cavities 15 are arranged outside the first hydrogen outlet cavity 16 and the second hydrogen outlet cavity 18 on the right side, showing an up-and-down layout;

[0035] There are two third coolant cavities 19 provided on the bipolar plate, and the two third coolant cavities 19 are located between the first coolant cavity 14 and the second coolant cavity 15

[0036] by Figures 1-3It can be seen that the internal structures of the first air outlet cavity 11, the hydrogen inlet cavity 12, the second air outlet cavity 13, the first coolant cavity 14, the second coolant cavity 15, the first hydrogen outlet cavity 16, the air inlet cavity 17 and the second hydrogen outlet cavity 18 are all the same ribbed component 6. The ribbed component 6 includes a reaction cavity 65, a flow field groove 61 arranged in the reaction cavity 65, two inlet and outlet ribs 63 arranged on one inner wall of the reaction cavity 65, a plurality of inlet pipes 64 arranged on the outer wall of the reaction cavity 65, and a plurality of connecting ribs 62 arranged on one outer wall of the reaction cavity 65. The flow field groove 61 is opened in the reaction cavity 65. The two inlet and outlet ribs 63 are connected to one inner wall of the reaction cavity 65 through pipelines, and the two inlet and outlet ribs 63 are communicated with the flow field groove 61. A plurality of inlet pipes 64 are respectively connected to the outer walls around the reaction cavity 65 through pipelines, and one end of each of the plurality of inlet pipes 64 penetrates the reaction cavity 65. A plurality of connecting ribs 62 are connected to one outer wall of the reaction cavity 65 through pipelines, and the plurality of connecting ribs 62 are communicated with the flow field groove 61;

[0037] It should be noted that taking the first air outlet cavity 11 as an example, the inlet pipe 64 is also an air inlet channel. The channel is composed of a plurality of connecting ribs 62 in the direction of the reaction zone 3 and is in a uniformly distributed state. Similarly, a channel for air inlet is designed on each of the other three sides. The internal channel of the flow field groove 61 serves as an air inlet buffer area. There are a plurality of connecting ribs 62 on the outer wall of the reaction cavity 65 that enter the flow field groove 61. Therefore, the process of air entering the flow field groove 61 is to first enter the interior of the reaction cavity 65 through the inlet and outlet ribs 63 around, then enter the flow field groove 61 through the inlet and outlet ribs 63, and then enter the flow field from the connecting ribs 62. The entire other operation path is straight-through. Compared with the conventional layer-by-layer structure, the path is shorter. Under the action of the buffer space, the flow resistance is lower. After entering the flow field groove 61, the air is divided into two streams under the action of the flow channel. One stream flows out from the second air outlet cavity 13 at the upper end, and the other stream flows out from the first air outlet cavity 11 at the lower end. After changing the conventional bipolar plate from one-in-one-out to one-in-two-out, the air flow resistance will be greatly improved, and the drainage and exhaust capacity will also be enhanced.

[0038] Example 1:

[0039] From Figure 1It can be seen that the inlet and outlet of the cooling water of the bipolar plate are arranged left and right, respectively on both sides of the air and hydrogen outlets. The first coolant chamber 14 serves as the cooling water inlet, and the second coolant chamber 15 serves as the cooling water outlet. When the cooling water enters the flow field area from the first coolant chamber 14 respectively, under the action of pressure, a part of the water in the lower first coolant chamber 14 will reach the outlet of the upper second coolant chamber 15, and another part of the water will reach the lower second coolant chamber 15. Similarly, a part of the water in the upper first coolant chamber 14 will reach the outlet of the lower second coolant chamber 15, and another part of the water will reach the upper second coolant chamber 15. The cooling water runs in a cross shape in the flow field area, and at the same time, a convection phenomenon is formed, greatly increasing the flow rate of the cooling water, reducing the flow resistance of the cooling water, and accelerating the heat dissipation efficiency of the bipolar plate.

[0040] Embodiment 2:

[0041] From Figure 2 It can be seen from the schematic diagram of the bipolar plate structure of Embodiment 2 that the bipolar plate structure of Embodiment 2 is similar to that of Embodiment 1 in terms of the hydrogen-air inlet and outlet mode and the internal structure of the chamber. In the local structure of the chamber, it enters the inside of the reaction chamber 65 through the inlet and outlet reinforcing ribs 63 around, and then enters the inside of the flow field groove 61 through the inlet and outlet reinforcing ribs 63, and then enters the flow field through the connecting reinforcing rib 62. After entering the flow field, the gas operation trajectory is the same as that of Embodiment 1, and no repeated description will be made here.

[0042] The difference compared with Embodiment 1 is that the cooling water inlet is introduced from the upper first coolant chamber 14, second coolant chamber 15 and third coolant chamber 19 to the lower first coolant chamber 14, second coolant chamber 15 and third coolant chamber 19. The number of inlet chambers also increases to 3 compared with Embodiment 1, and the number of outlet chambers also increases to 3 compared with Embodiment 1. When the cooling water enters from the upper first coolant chamber 14, second coolant chamber 15 and third coolant chamber 19 and reaches the flow field area, most of the cooling water in the upper first coolant chamber 14 will flow out from the lower first coolant chamber 14, and a small part will flow out from the second coolant chamber 15 and third coolant chamber 19. Most of the cooling water in the upper second coolant chamber 15 will flow out from the lower second coolant chamber 15, and a small part will flow out from the lower first coolant chamber 14 and third coolant chamber 19. Most of the cooling water in the upper third coolant chamber 19 will flow out from the lower third coolant chamber 19, and a small part will flow out from the lower first coolant chamber 14 and second coolant chamber 15. Therefore, the cooling water can not only run in a cross shape in the flow field, but also the running path is shortened by nearly half compared with the conventional plate type, the number of inlet and outlet chambers increases, and the flow resistance will become smaller, and the heat dissipation efficiency will be greatly improved.

[0043] Based on the inspiration of the ideal embodiments of the present utility model, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of the present utility model. The technical scope of the present utility model is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A bipolar plate structure for a high-power fuel cell, comprising two inlet and outlet regions (1), two distribution regions (2) and a reaction region (3). It is characterized in that; The inlet and outlet area (1) is divided into an inlet area and an outlet area located in the left and right side areas of the bipolar plate. The left side of the bipolar plate from top to bottom includes: a first coolant cavity (14), a second air outlet cavity (13), a hydrogen inlet cavity (12), a first air outlet cavity (11), and another first coolant cavity (14); the right side of the bipolar plate from top to bottom includes: a second coolant cavity (15), a first hydrogen outlet cavity (16), an air inlet cavity (17), a second hydrogen outlet cavity (18), and another third coolant cavity (19); The distribution area (2) is located inside the inlet and outlet area (1) and includes: a coolant flow path (100), an air flow path (120), and a hydrogen flow path (110); the coolant flow path (100), the air flow path (120), and the hydrogen flow path (110) connect the inlet and outlet area (1) and the reaction area (3), and the structures of the coolant flow path (100), the air flow path (120), and the hydrogen flow path (110) are all continuous strip-shaped flow channels; The two first coolant cavities (14) are arranged outside the left-side first air outlet cavity (11) and the second air outlet cavity (13) in an up-and-down layout, and the two second coolant cavities (15) are arranged outside the right-side first hydrogen outlet cavity (16) and the second hydrogen outlet cavity (18) in an up-and-down layout.

2. The bipolar plate structure of a high-power fuel cell according to claim 1, characterized in that: Two third coolant cavities (19) are provided on the bipolar plate, and the two third coolant cavities (19) are located between the first coolant cavity (14) and the second coolant cavity (15).

3. The bipolar plate structure of a high-power fuel cell according to claim 1, characterized in that: The reaction area (3) is located in the middle of the two distribution areas (2) on both sides, and the reaction area (3) connects the two inlet and outlet areas (1).

4. A bipolar plate structure for a high-power fuel cell according to claim 1, characterized in that: A number of ridges are provided in the reaction area (3), and a flow channel is provided between two adjacent ridges, and the flow channel is a channel for fluids.

5. The bipolar plate structure of a high-power fuel cell according to claim 4, characterized in that: The shape of the ridge is serpentine and arranged in a periodic pattern, and the ridges are parallel.

6. The bipolar plate structure of a high-power fuel cell according to claim 4, characterized in that: The cross-section of the ridge is rectangular, arc-shaped or trapezoidal, and the material of the bipolar plate is not limited to graphite or stainless steel metal plate.

7. The bipolar plate structure of a high-power fuel cell according to claim 1, wherein: The internal structures of the first air outlet cavity (11), the hydrogen inlet cavity (12), the second air outlet cavity (13), the first coolant cavity (14), the second coolant cavity (15), the first hydrogen outlet cavity (16), the air inlet cavity (17), and the second hydrogen outlet cavity (18) are all the same reinforcing rib assembly (6).

8. The bipolar plate structure of a high-power fuel cell according to claim 7, characterized in that: The reinforcing rib assembly (6) includes a reaction cavity (65), a flow field groove (61) provided in the reaction cavity (65), two inlet and outlet reinforcing ribs (63) provided on one inner wall of the reaction cavity (65), a number of inlet pipes (64) provided on the outer wall of the reaction cavity (65), and a number of connecting reinforcing ribs (62) provided on one outer wall of the reaction cavity (65).

9. The bipolar plate structure of a high-power fuel cell according to claim 8, characterized in that: The flow field groove (61) is opened in the reaction cavity (65), and the two inlet and outlet reinforcing ribs (63) are connected to one inner wall of the reaction cavity (65) by pipes, and the two inlet and outlet reinforcing ribs (63) are communicated with the flow field groove (61).

10. The bipolar plate structure of a high-power fuel cell according to claim 8, characterized in that: A plurality of the inlet pipes (64) are respectively connected to the pipes on the outer walls around the reaction cavity (65), and one end of each of the plurality of inlet pipes (64) penetrates through the reaction cavity (65). A plurality of the communication reinforcing ribs (62) are connected to the pipes on one outer wall of the reaction cavity (65), and the plurality of communication reinforcing ribs (62) are communicated with the flow field groove (61).

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