A split-flow reconstructive fuel cell bipolar plate

Abstract

The present invention relates to a split-flow reconstructable fuel cell bipolar plate, comprising two stacked metal plates, one side of each metal plate is provided with a first flow channel region, and the other side is provided with a second flow channel region, the two metal plates are relatively overlapped so that the second flow channel region overlaps to form a coolant flow channel, the first flow channel region comprises a plurality of rows of parallel unidirectional flow channels, wherein each unidirectional flow channel comprises a main flow channel and a plurality of auxiliary flow channels, the main flow channel is a wave-fold line structure, one end of each auxiliary flow channel is connected to the bending angle of the main flow channel, and the other end is connected to the middle of the bending section in the direction of the airflow outlet of the bending angle. Compared with the prior art, the present invention has the advantages of improving the diffusion efficiency of gas and improving the drainage effect.

Description

Technical Field

[0001] The present invention relates to the field of fuel cells, and in particular to a bipolar plate of a split-flow reconstructable fuel cell. Background Art

[0002] A fuel cell is a power generation device that is environmentally friendly, highly efficient, and has a long service life. Taking a proton exchange membrane fuel cell as an example, the fuel gas (hydrogen) enters the battery from the anode side of the battery. Hydrogen atoms become protons after losing electrons at the anode. The protons pass through the proton exchange membrane inside the battery to reach the cathode of the battery. At the same time, the electrons also reach the cathode of the battery through an external circuit. On the cathode side of the battery, protons, electrons and oxygen combine to form water, thereby generating current.

[0003] The gap between the fuel gas or oxygen flowing through the flow channel of the bipolar plate in the fuel cell and the proton exchange membrane is called the gas diffusion layer. The traditional flow channel is generally a linear groove structure, and the gas diffusion efficiency in the flow channel is low; on the other hand, as can be seen from the above, water will accumulate in the flow channel on the cathode side. The traditional flow channel structure has a small gas flow rate and poor drainage effect. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a split-flow reconstructible fuel cell bipolar plate to improve the gas diffusion efficiency and drainage effect.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A split-flow reconstructible fuel cell bipolar plate comprises two stacked metal plates, one side of each metal plate is provided with a first flow channel region, and the other side is provided with a second flow channel region, the two metal plates are relatively overlapped so that the second flow channel regions overlap to form a coolant flow channel, the first flow channel region comprises a plurality of rows of parallel unidirectional flow channels, wherein each unidirectional flow channel comprises a main flow channel and a plurality of auxiliary flow channels, the main flow channel is a wavy fold line structure, one end of each auxiliary flow channel is connected to the bending corner of the main flow channel, and the other end is connected to the middle of the bending section in the airflow outlet direction of the bending corner.

[0007] Furthermore, the auxiliary flow channel is semicircular or arcuate.

[0008] Furthermore, the bending angle is tangent to the auxiliary flow channel.

[0009] Furthermore, the bending angle ranges from 90 to 120 degrees.

[0010] Furthermore, the length of each auxiliary flow channel is 4 to 8 mm.

[0011] Furthermore, a first gas inlet, a second gas inlet and a coolant inlet are provided at one end of each metal electrode plate, and a first gas outlet, a second gas outlet and a coolant outlet are provided at the other end of the metal electrode plate, and the two ends of the first flow channel area are respectively connected to the first gas inlet and the first gas outlet.

[0012] Furthermore, a confluence area is provided at both ends of each first flow channel region, and both ends of each unidirectional flow channel are connected to the first gas inlet or the first gas outlet through the confluence area.

[0013] Furthermore, a diversion column is provided in the confluence area.

[0014] Furthermore, the first gas inlet and the first gas outlet are arranged diagonally.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the present invention designs a flow-dividing reconstructed flow channel composed of a main flow channel and a plurality of auxiliary flow channels, which can make the gas flow stable and uniform, and form a relatively uniform and stable reaction gas concentration on the entire flow channel surface, which is conducive to mass transfer and diffusion. At the same time, the present invention can realize the flow diversion and confluence of the gas through the main flow channel and the plurality of auxiliary flows, thereby accelerating the gas flow, which is conducive to drainage in the flow channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the metal plate.

[0017] Figure 2 It is a structural schematic diagram of a one-way flow channel.

[0018] Figure 3 This is a pressure diagram of the flow channel working principle.

[0019] Figure 4 It is a vector diagram of the working principle of the flow channel.

[0020] Figure 5 This is a streamline diagram showing the working principle of the flow channel.

[0021] Description of the drawings: 1-first flow channel area, 11-one-way flow channel, 11a-main flow channel, 11b-auxiliary flow channel, 2-first gas inlet, 3-second gas inlet, 4-cooling liquid inlet, 5-first gas outlet, 6-second gas outlet, 7-cooling liquid outlet, 8-convergence area, 9-dividing column. DETAILED DESCRIPTION

[0022] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0023] This embodiment provides a split-flow reconfigurable fuel cell bipolar plate, comprising two stacked metal plates. The two metal plates have the same structure, both of which have a first flow channel region 1 on the front and a second flow channel region on the back. The backs of the two metal plates overlap relative to each other so that the second flow channel regions overlap to form a coolant flow channel. Figure 1 As shown, the first flow channel region 1 of one metal plate is the anode flow channel region, and the first flow channel region 1 of the other metal plate is the cathode flow channel region. The upper end of each metal plate is provided with a first gas inlet 2, a second gas inlet 3 and a coolant inlet 4, the first gas inlet 2, i.e., the fuel gas inlet, is located at the leftmost end, the second gas inlet 3, i.e., the air inlet, is located at the rightmost end, and the coolant inlet 4 is located in the middle. The lower end of the metal plate is provided with a first gas outlet 5, a second gas outlet 6 and a coolant outlet 7, the first gas outlet 5, i.e., the fuel gas outlet, is located at the rightmost end, the second gas outlet 6, i.e., the air outlet, is located at the leftmost end, and the coolant outlet 7 is located in the middle. A confluence area 8 is also provided at both ends of the first flow channel region 1, and the two ends of each unidirectional flow channel 11 are connected to the first gas inlet 2 or the first gas outlet 5 through the confluence area 8, respectively. A diverter column 9 is provided in the confluence area 8 for diffusing and converging gases.

[0024] like Figure 2 As shown, the first flow channel area 1 includes multiple rows of unidirectional flow channels 11 arranged in parallel, wherein each unidirectional flow channel 11 includes a main flow channel 11a and multiple auxiliary flow channels 11b. The two ends of the main flow channel 11a are connected to the confluence area 8, and the main flow channel 11a is a wavy broken line structure, and the bending angle ranges from 90 to 120 degrees in general, preferably 120 degrees. The auxiliary flow channel 11b can be semicircular or bow-shaped, preferably semicircular. One end of each auxiliary flow channel 11b is connected to the bending angle of the main flow channel 11a, and the other end is connected to the middle of the bending section at the rear end of the bending angle. The length of each auxiliary flow channel is 4 to 8 mm, preferably 6 mm. The bending angle can be tangent to the connection of the auxiliary flow channel 11b to improve the stability of the gas passing through.

[0025] The principle of the one-way flow channel 11 in this embodiment is as follows Figure 3 As shown, the gas flows in from the left side, first splits and then merges, which will produce a pressure change, that is, the pressure relationship is P1>P2>P3. Figure 4 and Figure 5 In the process, due to the disturbance caused by the flow splitting and converging, the pressure drop is increased, and secondary flow is generated, which increases the momentum of the gas on the one hand, and dissipates the energy through the vortex on the other hand. This is conducive to the convection diffusion mass transfer of the gas. Due to the characteristics of the structure, the flow splitting and converging can make the gas pass quickly, which is conducive to drainage in the flow channel.

[0026] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A split-flow reconfigurable fuel cell bipolar plate, comprising two stacked metal plates, each of which has a first flow channel region (1) on one side and a second flow channel region on the other side, the two metal plates are relatively overlapped so that the second flow channel regions overlap to form a coolant flow channel, characterized in that: The first flow channel region (1) comprises a plurality of rows of unidirectional flow channels (11) arranged in parallel, wherein each unidirectional flow channel (11) comprises a main flow channel (11a) and a plurality of auxiliary flow channels (11b), the main flow channel (11a) being a wave-shaped broken line structure, and one end of each auxiliary flow channel (11b) being connected to a bending angle of the main flow channel (11a), and the other end being connected to the middle of a bending section in the airflow outlet direction of the bending angle; The auxiliary flow channel (11b) is semicircular or arcuate; The bending angle is tangent to the auxiliary flow channel (11b); The bending angle ranges from 90 to 120 degrees.

2. A split-flow reconfigurable fuel cell bipolar plate according to claim 1, characterized in that: The length of each auxiliary flow channel (11b) is 4 to 8 mm.

3. The split-flow reconfigurable fuel cell bipolar plate according to claim 1, characterized in that: A first gas inlet (2), a second gas inlet (3) and a coolant inlet (4) are provided at one end of each metal electrode plate, a first gas outlet (5), a second gas outlet (6) and a coolant outlet (7) are provided at the other end of the metal electrode plate, and the two ends of the first flow channel region (1) are respectively connected to the first gas inlet (2) and the first gas outlet (5).

4. A split-flow reconfigurable fuel cell bipolar plate according to claim 3, characterized in that: A confluence area (8) is provided at both ends of the first flow channel region (1), and both ends of each unidirectional flow channel (11) are connected to the first gas inlet (2) or the first gas outlet (5) through the confluence area (8).

5. A split-flow reconfigurable fuel cell bipolar plate according to claim 4, characterized in that: A flow dividing column (9) is provided in the confluence area (8).

6. A split-flow reconfigurable fuel cell bipolar plate according to claim 3, characterized in that: The first gas inlet (2) and the first gas outlet (5) are arranged diagonally.

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