CN113130931A

CN113130931A - Bipolar plate for hydrogen fuel cell

Info

Publication number: CN113130931A
Application number: CN202110330950.0A
Authority: CN
Inventors: 徐一凡; 翟桂珍; 唐厚闻
Original assignee: Shanghai H Rise New Energy Technology Co Ltd
Current assignee: Shanghai H Rise New Energy Technology Co Ltd
Priority date: 2021-03-27
Filing date: 2021-03-27
Publication date: 2021-07-16

Abstract

The invention relates to a bipolar plate for a hydrogen fuel cell, which comprises two metal polar plates which are arranged in a stacking mode, wherein each metal polar plate comprises a first surface and a second surface, a first flow channel is arranged on the first surface, a second flow channel is arranged on the second surface, the second surfaces of the two metal polar plates are relatively overlapped to enable the second flow channels to be overlapped to form a cooling liquid flow channel, the first flow channel comprises a groove part and a ridge part, the groove part and the ridge part are arranged in a staggered and parallel mode, a plurality of bypass grooves are further distributed in the first flow channel, each bypass groove obliquely penetrates through the ridge part, and two ends of each bypass groove are respectively communicated with two adjacent groove parts. Compared with the prior art, the inclined bypass groove is arranged in the flow channel, so that the area of the ridge part is reduced, and accumulated water under the ridge can be discharged into the adjacent groove part more easily by generating airflow through the pressure difference at the two ends of the bypass groove, thereby being beneficial to discharging the water under the ridge; meanwhile, the bypass groove can be used as a supplement of the groove part to enhance the direct diffusion area of the gas, so that the gas diffusion is more uniform.

Description

Bipolar plate for hydrogen fuel cell

Technical Field

The invention relates to the field of fuel cells, in particular to a bipolar plate for a hydrogen fuel cell.

Background

The fuel cell is a power generation device with the characteristics of environmental friendliness, high working efficiency, long service life and the like. Taking a hydrogen fuel cell (proton exchange membrane fuel cell) as an example, hydrogen enters the cell from the anode side of the cell, hydrogen atoms become protons after the anode loses electrons, the protons pass through the proton exchange membrane in the cell to reach the cathode of the cell, meanwhile, the electrons also reach the cathode of the cell through an external loop, and at the cathode side of the cell, the protons, the electrons and oxygen are combined to generate water, thereby generating current.

The existing hydrogen fuel cell has the following problems: the flow channel of the bipolar plate in the fuel cell is used for passing gas, and the gap between the flow channel and the proton exchange membrane is a gas diffusion layer. As can be seen from the foregoing, water generated in the gas diffusion layer (cathode side) corresponding to the cathode metal plate of the fuel cell needs to be removed in time. The flow channels of the bipolar plate generally comprise ridges and grooves, the production water in the groove area is easy to be carried out along with the air flow, but the ridge area is easy to accumulate water due to small air flow, thereby affecting the working efficiency of the fuel cell.

Disclosure of Invention

The present invention is directed to overcoming the above-mentioned drawbacks of the prior art, and providing a bipolar plate for a hydrogen fuel cell, which is used to improve the under-ridge drainage capability of the flow channels of the bipolar plate.

The purpose of the invention can be realized by the following technical scheme:

a bipolar plate for a hydrogen fuel cell comprises two metal polar plates which are arranged in a stacked mode, wherein each metal polar plate comprises a first surface and a second surface, a first flow channel is arranged on the first surface, a second flow channel is arranged on the second surface, the second surfaces of the two metal polar plates are relatively overlapped to enable the second flow channels to be overlapped to form a cooling liquid flow channel, the first flow channel comprises a groove portion and a ridge portion, the groove portion and the ridge portion are arranged in a staggered and parallel mode, a plurality of bypass grooves are further distributed in the first flow channel, each bypass groove penetrates through the ridge portion in an inclined mode, and two ends of each bypass groove are communicated with two adjacent groove portions respectively.

Further, all the side through grooves are arranged in parallel.

Further, all the side through grooves are distributed in a flush manner in a matrix arrangement.

Further, the bypass grooves on two adjacent ridges are symmetrically arranged by taking the axis of the middle groove of the two ridges as a center line.

Further, the ridges are divided into odd ridges and even ridges which are adjacent in a staggered manner, and the bypass grooves on the odd ridges and the bypass grooves on the even ridges are arranged in a staggered manner.

Further, the bypass grooves on the odd ridges and the bypass grooves on the even ridges are inclined in opposite directions.

Further, the bottom surface in the groove part is provided with pit structures, and the pit structures are distributed along the axial direction of the groove part.

Further, the groove portion is divided into a singular groove portion and an even groove portion which are adjacent in an alternating manner, and the pit structure on the singular groove portion and the pit structure on the even groove portion are arranged in an alternating manner.

Furthermore, the total width of a ridge part and a groove part in the flow channel is 1-1.2 mm.

Compared with the prior art, the invention has the following beneficial effects:

(1) the inclined bypass groove is arranged in the flow channel, so that the area of the ridge part is reduced, and accumulated water under the ridge can be discharged into the adjacent groove part more easily by generating airflow through the pressure difference at the two ends of the bypass groove, so that the drainage of the water under the ridge is facilitated; meanwhile, the bypass groove can be used as a supplement of the groove part to enhance the direct diffusion area of the gas, so that the gas diffusion is more uniform.

(2) The concave pit structures are arranged in the groove parts of the flow channel, so that the convection flow of gas in the flow channel is further strengthened, the diffusion of the gas to the membrane electrode is enhanced, and the concave pit structures can be arranged in a staggered mode, so that the pressure difference between the adjacent groove parts is enhanced, and the effect of discharging accumulated water at the ridge parts is improved.

(3) The bypass groove can be formed by staggering the single rows and the double rows, and the inclination directions are opposite, so that the air flow pressure is more balanced, and the condition of local water accumulation in the groove part is avoided.

(4) The ridge and the groove in the flow channel are designed in a fine and compact mode, so that the contact area of the ridge and the gas diffusion layer is increased, the contact resistance is effectively reduced, and meanwhile, the ridge width is reduced, and the water drainage under the ridge is facilitated.

Drawings

Fig. 1 is a schematic structural diagram of the first embodiment.

Fig. 2 is a partially enlarged schematic view of the first flow channel according to the first embodiment.

Fig. 3 is a schematic cross-sectional view of the first flow channel.

Fig. 4 is a schematic structural diagram of the second embodiment.

Fig. 5 is a schematic structural diagram of the third embodiment.

Description of the drawings: 1. the first flow channel, 11, the groove part, 11a, the odd number groove part, 11b, the even number groove part, 12, the odd number ridge part, 12a, the even number ridge part, 12b, the ridge part, 13, the bypass groove, 14, the pit structure.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

Example one

The embodiment provides a bipolar plate for a hydrogen fuel cell, which comprises two metal plates which are arranged in a stacked mode. As shown in fig. 1 and 2, the front and back surfaces of each metal plate are respectively a first surface and a second surface, the first surface is provided with a first flow channel, and the second surface is provided with a second flow channel. The second surfaces of the two metal polar plates are relatively overlapped to ensure that the second flow channels are overlapped to form a cooling liquid flow channel. The first flow channel 1 specifically includes groove portions 11 and ridge portions 12 arranged in parallel in an alternating manner. In the present embodiment, the ridge portion 12 and the groove portion 11 in the flow channel are designed to be fine, and as shown in fig. 3, the total width D of one ridge portion 12 and one groove portion 11 in the flow channel is 1 to 1.2mm, preferably 0.8 mm. The compact design can increase the contact area of the ridge 12 and the gas diffusion layer, effectively reduce the contact resistance, and simultaneously reduce the ridge width, thereby being beneficial to draining water under the ridge.

A plurality of bypass grooves 13 are further distributed in the first flow channel 1, each bypass groove 13 penetrates through the ridge 12 in an inclined mode, and two ends of each bypass groove 13 are communicated with two adjacent groove parts 11 respectively.

The ridges 12 are divided into alternating adjacent odd ridges 12a first ridge 12, third ridge 12, fifth ridge 12 … … and even ridges 12b second ridge 12, fourth ridge 12, sixth ridge 12 … …. The bypass grooves 13 on all the odd-numbered ridges 12a are arranged in parallel and flush, and at the same time, the bypass grooves 13 on the odd-numbered ridges 12a and the bypass grooves 13 on the even-numbered ridges 12b are arranged alternately. Further, the bypass grooves 13 on the odd-numbered ridges 12a and the bypass grooves 13 on the even-numbered ridges 12b are also inclined in opposite directions. When the gas flows through the bypass grooves 13, pressure difference is generated between the outlet of the bypass groove 13 and the adjacent groove 11, so that accumulated water under the ridge can be more easily discharged into the adjacent groove 11, and the drainage of water under the ridge is facilitated; meanwhile, the bypass grooves 13 can supplement the grooves 11 to increase the direct gas diffusion area, so that the gas diffusion is more uniform. The staggered and reversely inclined bypass structure can make the pressure distribution more uniform, thereby enhancing the mass transfer and the water drainage.

The bottom surface in the groove 11 is also provided with pit structures 14, and the pit structures 14 are distributed along the axial direction of the groove 11. The pit structures 14 between adjacent groove portions 11 are all arranged flush. When the gas flows through the pit structures 14, momentum exchange of the gas in the height direction is enhanced, the turbulence degree of the flow is increased, so that mass transfer diffusion of the gas is enhanced, the gas flow can enter the bypass grooves 13 more conveniently, and accumulated water in the ridge part 12 is discharged.

Example two

The overall structure of the present embodiment is similar to that of the embodiment, except that all the bypass grooves 13 are arranged in a matrix in parallel and flush with each other in the first flow channel.

EXAMPLE III

The whole structure of the present embodiment is similar to that of the embodiment, and the difference is that the two ridges 12 of the bypass groove 13 of the adjacent two ridges 12 are symmetrically arranged with the axis of the middle groove 11 as the center line. The groove 11 is divided into an odd number groove 11a and an even number groove 11b adjacent to each other in an alternating manner, and the dimple structure 14 in the odd number groove 11a and the dimple structure 14 in the even number groove 11b are arranged in an alternating manner. The staggered pit structure 14 is beneficial to enhancing the pressure difference between the adjacent groove parts 11 and improving the drainage effect of water generated by the ridge part 12.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims

1. The bipolar plate for the hydrogen fuel cell comprises two metal polar plates which are arranged in a stacked mode, each metal polar plate comprises a first surface and a second surface, a first flow channel (1) is arranged on the first surface, a second flow channel is arranged on the second surface, the second surfaces of the two metal polar plates are relatively overlapped to enable the second flow channels to be overlapped to form a cooling liquid flow channel, the first flow channel (1) comprises a groove portion (11) and ridge portions (12), the groove portion (11) and the ridge portions (12) are arranged in a staggered and parallel mode, the bipolar plate is characterized in that a plurality of side through grooves (13) are further distributed in the first flow channel (1), each side through groove (13) obliquely penetrates through the ridge portions (12), and two ends of each side through groove (13) are respectively communicated with two adjacent groove portions (11).

2. A bipolar plate for a hydrogen fuel cell according to claim 1, wherein all the bypass grooves (13) are arranged in parallel with each other.

3. A bipolar plate for a hydrogen fuel cell according to claim 2, wherein all the bypass grooves (13) are arranged flush in a matrix arrangement.

4. A bipolar plate for a hydrogen fuel cell according to claim 1, wherein the bypass grooves (13) in adjacent two ridges (12) are arranged symmetrically with respect to the axis of the groove (11) in the middle of the two ridges (12).

5. The bipolar plate for a hydrogen fuel cell according to claim 1, wherein the ridges (12) are divided into a single ridge (12a) and a double ridge (12b) which are alternately adjacent, and the bypass grooves (13) on the single ridge (12a) and the bypass grooves (13) on the double ridge (12b) are alternately arranged.

6. A bipolar plate for a hydrogen fuel cell according to claim 5, wherein the bypass grooves (13) on the singular ridges (12a) and the bypass grooves (13) on the plural ridges (12b) are inclined in opposite directions.

7. The bipolar plate for a hydrogen fuel cell according to claim 1, wherein a dimple structure (14) is provided on the bottom surface in the groove portion (11), and the dimple structure (14) is distributed along the axial direction of the groove portion (11).

8. The bipolar plate for a hydrogen fuel cell according to claim 7, wherein the groove portion (11) is divided into a singular groove portion (11a) and an even groove portion (11b) which are alternately adjacent, and the dimple structure (14) on the singular groove portion (11a) and the dimple structure (14) on the even groove portion (11b) are alternately arranged.

9. The bipolar plate for a hydrogen fuel cell according to claim 1, wherein the total width of a ridge portion (12) and a groove portion (11) in the flow channel is 1 to 1.2 mm.