CN102117922A - Flat plate type fuel cell module and flow field plate thereof - Google Patents

Abstract

The present invention provides a flat fuel cell module and a flow field plate thereof, wherein the flow field plate is arranged in a fuel cell module and includes at least two flow channels, a first manifold and a second manifold. The at least two flow channels are formed on opposite sides of the flow field plate, respectively, and the first and second manifolds are formed inside the flow field plate, wherein the first and second manifolds are connected to the at least two flow channels. The reaction fluid enters the flow field plate from the first manifold, and after passing through the at least two flow channels, it converges into the second manifold, and then is discharged from the flow field plate from the second manifold.

Description

Flat fuel cell module and its flow field plate

technical field

The present invention relates to a flow field plate, in particular to a flow field plate arranged in a flat fuel cell module.

Background technique

First please refer to Fig. 1, the single cell structure (single cell) 400 of the known proton exchange membrane fuel cell (Proton Exchange Membrane Fuel Cell, PEMFC) mainly includes a membrane electrode assembly 410 (membrane electrode assembly, MEA), two gas diffusion Layers 405, 406 (gas diffusion layer, GDL) and two flow field plates 401, 402 (fluid flow plate). The inner surfaces of the two flow field plates 401, 402 are respectively formed with independent flow channels (flow channels) 403, 404, which can be used to transport the reaction fluid. The membrane electrode group 410 mainly includes a proton exchange membrane 409 1. Anode (anode) catalyst layer 407 and cathode (cathode) catalyst layer 408, wherein the catalyst layers 407, 408 usually have platinum or platinum alloy and other components to facilitate the fuel cell to perform electrochemical reactions (electrochemical reactions) and provide power output.

In the flow field plate of a general small fuel cell, the size of the flow channel and manifold is usually smaller than that of a large fuel cell, so the flow resistance of the reaction fluid is relatively increased, which will lead to the concentration of the reaction fluid on the flow field plate Uneven distribution affects the performance of the fuel cell. In view of this, how to improve the structure design of the flow channels and manifolds on the known flow field plate, so that the reaction fluid can be evenly delivered to each area on the flow field plate, and thus improve the overall performance of the fuel cell has become the focus of the miniaturization of the fuel cell. important topic.

Contents of the invention

The technical problem to be solved by the present invention is to provide a flat fuel cell module and its flow field plate which can uniformly transport the reaction fluid to each area of the flow field plate, thereby improving the overall performance of the fuel cell.

An embodiment of the present invention provides a flow field plate, which is arranged in a fuel cell module and includes at least two flow channels, a first branch channel and a second branch channel, wherein the at least two flow channels respectively form on the opposite side of the flow field plate. The first and second manifolds are formed inside the flow field plate and are approximately parallel to a central axis of the flow field plate, wherein the first and second manifolds communicate with the at least two flow channels. The reaction fluid enters the flow field plate from the first manifold, flows into the second manifold after passing through the at least two flow channels, and then exits the flow field plate from the second manifold.

In one embodiment, the first manifold has two notches, respectively communicated with the at least two flow channels, wherein the angle corresponding to each notch relative to a geometric center position of a section of the first manifold is between Between 0° and 90°.

In one embodiment, the second manifold has at least two notches, respectively communicated with the at least two flow channels, and each notch is at an angle corresponding to a geometric center position of a section of the second manifold. between 0° and 90°.

In one embodiment, the first branch channel has four notches, which communicate with the at least two flow channels respectively and are symmetrical to the first branch channel, wherein each notch is relative to a section geometric center of the first branch channel Angles corresponding to the positions are respectively between 0° and 90°.

In an embodiment, the flow field plate further includes two second manifolds, wherein the first manifold is located on the central axis, and the two second manifolds are respectively located on opposite sides of the first manifold.

In one embodiment, the at least two flow channels are arranged in an array on opposite sides of the flow field plate.

In one embodiment, the at least two flow channels are arranged along the direction of the central axis of the flow field plate.

An embodiment of the present invention also provides a flat fuel cell module, which includes two core units and two sealing elements in addition to the flow field plate with the above structure and characteristics, wherein the flow field plate is arranged on the two cores between the units, and each core unit includes a membrane electrode group, two gas diffusion layers and a plurality of collector elements, the two gas diffusion layers and a plurality of collector elements are arranged on both sides of the membrane electrode group, so The two sealing elements are respectively arranged on the outer sides of the two core units, and are respectively connected with the two core units.

According to the flat fuel cell module and its flow field plate of the present invention, since the first and second manifolds are arranged inside the flow field plate, at least one flow channel is respectively formed on both sides of the flow field plate, wherein the reaction fluid can be obtained by The first end of the flow field plate enters the first branch channel, passes through the flow channel and enters the second branch channel, and then is discharged from the second end of the flow field plate. Because the first and second manifolds are formed inside the flow field plate, the flow resistance can be reduced, so that the reaction fluid can be quickly and effectively delivered to each area of the flow field plate, and at the same time, the reaction fluid can be prevented from being trapped in the flow field plate. The uneven concentration distribution in the fuel cell improves the overall performance of the fuel cell.

Description of drawings

In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and understandable, the preferred embodiments are specifically cited below, together with the accompanying drawings, and are described in detail as follows:

Fig. 1 shows the schematic diagram of the unit cell structure of known proton exchange membrane fuel cell;

Figure 2 shows a schematic diagram of a flat fuel cell module according to an embodiment of the present invention;

FIG. 3A shows a schematic diagram of a flow field plate according to an embodiment of the present invention;

Figure 3B shows a cross-sectional view of the flow field plate in Figure 3A;

FIG. 4A shows a schematic diagram of a flow field plate according to another embodiment of the present invention;

Figure 4B shows a cross-sectional view of the flow field plate in Figure 4A;

FIG. 5A shows a schematic diagram of a flow field plate according to another embodiment of the present invention;

Figure 5B shows a cross-sectional view of the flow field plate in Figure 5A; and

Fig. 5C shows a cross-sectional view along X1-X2 in Fig. 5B.

[Description of main reference signs]

Flow field plate 10

first end 101

second end 102

First branch 11

Notch 110

Second Branch 12

Sealing element 20

Core Unit 30

Collector element 31

Single cell structure 400

Flow field plates 401, 402

Runner 403, 404

Gas diffusion layers 405, 406

Catalyst layers 407, 408

PEM 409

MEA 410

Central axis A

Runner C

Gap G

Connector R

First side S1

Second side S2

Angle θ

Detailed ways

Please refer to FIG. 2 , a flat-plate fuel cell module according to an embodiment of the present invention mainly includes a flow field plate 10, two sealing members 20 (sealing member) and two core units 30, each of which is composed of a membrane It consists of an electrode group, two gas diffusion layers, and multiple collector elements 31 . The structures of the membrane electrode group and the gas diffusion layer can refer to the membrane electrode group 410 and the gas diffusion layers 405 and 406 shown in FIG. 1 . In the core unit 30 of this embodiment, the gas diffusion layer and the collector element 31 are arranged on both sides (the anode side and the cathode side) of the membrane electrode group, and the collector element 31 is exposed on the surface of the core unit 30 to facilitate fuel flow. Electrochemical reactions inside the battery module.

As shown in FIG. 2, the flow field plate 10 is sandwiched in the gap G between two core units 30, wherein at least one flow channel C is formed on the first side S1 and the second side S2 of the flow field plate 10 respectively. In addition, the two core units 30 can also be connected to each other through a connector R, and the sealing element 20 is arranged on the outside of the two core units 30, and respectively bonded to the surface of the core unit 30, thus forming a multi-layer Structural planar fuel cell module.

Next please refer to FIG. 3A , the flow field plate 10 in this embodiment is roughly in a rectangular structure, and the flow channels C are arranged along a central axis A of the flow field plate 10, and are respectively exposed on the sides of the flow field plate 10. First and second sides S1, S2. In addition, a first manifold 11 and a second manifold 12 are additionally formed inside the flow field plate 10. The first and second manifolds 11, 12 are approximately parallel to the central axis A and are respectively connected to the flow field plate 10. Each flow channel C on both sides communicates.

It should be understood that the reactive fluid (reactant fluid) can enter the first manifold 11 from the first end 101 of the flow field plate 10, and then enter the second manifold 12 after passing through the flow channel C, and finally pass through the flow field The second end 102 of the plate 10 exits (as shown in the direction of the arrow in FIG. 3A ). Because the first and second manifolds 11 and 12 in this embodiment are formed inside the flow field plate 10 and extend along the direction of the central axis A of the flow field plate 10, the flow resistance can be reduced so that the reaction fluid can flow quickly. And it can be effectively transported to various regions of the flow field plate 10, and the uneven concentration distribution of the reaction fluid in the flow field plate 10 can be avoided, thereby improving the efficiency of the fuel cell.

Referring to FIG. 3B again, the first manifold 11 in this embodiment has a circular cross-section, and in particular, notches 110 are respectively formed on the lower left side and the lower right side of the first manifold 11, and the notches 110 are respectively connected with The flow channels C of the first and second sides S1 and S2 are connected. It can be seen from FIG. 3B that the angle θ corresponding to each notch 110 relative to the geometric center of the section of the first manifold 11 is approximately between 0°˜90°. In addition, the second manifold 12 can also form a structure similar to the notch 110 , wherein the angle corresponding to the notch of the second manifold 12 relative to the geometric center of its section is also between 0° and 90°.

4A and 4B at the same time, the flow field plate 10 of another embodiment of the present invention is also formed with flow channels C on the first and second sides S1 and S2, and in addition, a first flow field plate 10 is formed inside the flow field plate 10. One branch 11 and two second branches 12 . As shown in Figures 4A and 4B, the first manifold 11 is located on the central axis A of the flow field plate 10, and the two second manifolds 12 are respectively located on the upper and lower sides of the first manifold 11, wherein The first and second manifolds 11 and 12 communicate with the flow channels C on the first and second sides S1 and S2, thereby reducing flow resistance and allowing the reaction fluid to be quickly and effectively delivered to each of the flow field plates 10 area.

Please refer to Fig. 5A and 5B at the same time. The flow field plate 10 of another embodiment of the present invention is also formed with flow channels C on the first and second sides S1 and S2, but the flow channels C in this embodiment are They are arranged on both sides of the flow field plate 10 in a two-dimensional array. It should be understood that the first and second manifolds 11 and 12 are formed inside the flow field plate 10 and communicate with the respective flow channels C on the first and second sides S1 and S2, thereby reducing flow resistance and The reactive fluid is quickly and efficiently delivered to various regions of the flow field plate 10 .

As shown in the direction of the arrow in Figures 5A and 5B, the reaction fluid can enter the first manifold 11 from the first end 101 of the flow field plate 10, and then enter the second manifold 12 after passing through the flow channel C, and then It is discharged from the second end 102 of the flow field plate 10 . Conversely, it is also possible to make the reaction fluid enter the second manifold 12 from the second end 102 of the flow field plate 10, and flow into the first manifold 11 through the flow channel C, and then flow from the flow field plate 10 The first end portion 101 is discharged from the flow field plate 10 , and the two kinds of motions can make the reaction fluid rapidly and effectively transported to various regions of the flow field plate 10 , so as to facilitate the electrochemical reaction inside the fuel cell.

Next, please refer to FIG. 5C. In this embodiment, the first manifold 11 has a circular cross-section. In particular, notches 110 are respectively formed on the upper left, lower left, upper right, and lower right sides of the first manifold 11. Through The gap 110 can make the first branch channel 11 communicate with the flow channel C located on the first and second sides S1 and S2. As shown in FIG. 5C , the notches 110 are symmetrically formed on the first manifold 11 , wherein the angle θ corresponding to each notch 110 relative to the geometric center position of the section of the first manifold 11 is about 0°. ~90°.

To sum up, the present invention provides a flat fuel cell module and its flow field plate, wherein first and second manifolds are arranged inside the flow field plate, and at least one flow channel is formed on both sides of the flow field plate respectively. channels, wherein the reaction fluid can enter the first manifold from the first end of the flow field plate, and enter the second manifold after passing through the at least one flow channel, and then be discharged from the second end of the flow field plate. Because the first and second manifolds are formed inside the flow field plate, the flow resistance can be reduced, so that the reaction fluid can be quickly and effectively delivered to each area of the flow field plate, and at the same time, the reaction fluid can be prevented from being trapped in the flow field plate. The uneven concentration distribution in the fuel cell improves the overall performance of the fuel cell.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person familiar with this technology can make changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection should depend on the scope defined by the claims.

Claims (14)

1. a flow-field plate is arranged in the flat fuel cell module, it is characterized in that, comprising:

At least two runners are formed at the opposition side of this flow-field plate respectively;

One first divergent road is formed at this flow-field plate inside, and is roughly parallel to a central axis direction of this flow-field plate, and wherein these at least two runners in first divergent road and this communicate; And

One second divergent road, be formed at this flow-field plate inside, and be roughly parallel to this central axis direction, wherein these at least two runners in second divergent road and this communicate, one reacting fluid enters this flow-field plate from this first divergent road, and, discharge this flow-field plate by this second divergent road again through importing this second divergent road at least behind these two runners.

2. flow-field plate according to claim 1, it is characterized in that, wherein this first divergent road has two breach, communicate with these at least two runners respectively, and each this breach with respect to the pairing angle in a cross section geometric center in this first divergent road between 0 °～90 °.

3. flow-field plate according to claim 1, it is characterized in that, wherein this second divergent road has at least two breach, communicate with these at least two runners respectively, and each this breach with respect to the pairing angle in a cross section geometric center in this second divergent road between 0 °～90 °.

4. flow-field plate according to claim 1, it is characterized in that, wherein this flow-field plate also comprises four runners, be formed at the opposition side of this flow-field plate, and this first divergent road has four breach, be symmetrical in this first divergent road and communicate with these four runners respectively, wherein each this breach with respect to the pairing angle in a cross section geometric center in this first divergent road between 0 °～90 °.

5. flow-field plate according to claim 1 is characterized in that, wherein this flow-field plate also comprises two second divergent roads, and this first divergent road is positioned on this central shaft, and these two second divergent roads lay respectively at the opposition side in this first divergent road.

6. flow-field plate according to claim 1 is characterized in that, wherein these at least two runners are disposed at this flow-field plate opposition side with array way.

7. flow-field plate according to claim 1 is characterized in that, wherein these at least two runners are arranged along this central axis direction.

8. a flat fuel cell module is characterized in that, comprising:

Two core cells, wherein these two core cells comprise a mea, two gas diffusion layers and a plurality of current collection element respectively, wherein these two gas diffusion layers and this a plurality of current collection elements are arranged at the both sides of this mea;

One flow-field plate according to claim 1 is arranged between these two core cells; And

Two potted components are arranged at this two core cells outside and interconnect with these two core cells respectively.

9. flat fuel cell module according to claim 8, it is characterized in that, wherein this first divergent road has two breach, communicate with these at least two runners respectively, and each this breach with respect to the pairing angle in a cross section geometric center in this first divergent road between 0 °～90 °.

10. flat fuel cell module according to claim 8, it is characterized in that, wherein this second divergent road has at least two breach, communicate with these at least two runners respectively, and each this breach with respect to the pairing angle in a cross section geometric center in this second divergent road between 0 °～90 °.

11. flat fuel cell module according to claim 8, it is characterized in that, wherein this flow-field plate also comprises four runners, be formed at the opposition side of this flow-field plate, and this first divergent road has four breach, be symmetrical in this first divergent road and communicate with these four runners respectively, wherein each this breach with respect to the pairing angle in a cross section geometric center in this first divergent road between 0 °～90 °.

12. flat fuel cell module according to claim 8 is characterized in that, wherein this flow-field plate also comprises two second divergent roads, and this first divergent road is positioned on this central shaft, and these two second divergent roads lay respectively at the opposition side in this first divergent road.

13. flat fuel cell module according to claim 8 is characterized in that, wherein these at least two runners are disposed at this flow-field plate surface with array way.

14. flat fuel cell module according to claim 8 is characterized in that, wherein these at least two runners are arranged along this central axis direction.

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