Polar plate, electric pile and fuel cell

Abstract

The invention provides a polar plate, an electric pile and a fuel cell, the polar plate comprises a distribution area and an activation area which are communicated with each other, a plurality of first flow channels distributed at intervals are arranged in the distribution area, a plurality of second flow channels distributed at intervals are arranged in the activation area, and the plurality of first flow channels are communicated with the plurality of second flow channels for fluid circulation. The included angle between the side wall of the first flow channel and the bottom wall of the first flow channel is a, and the included angle between the side wall of the second flow channel and the bottom wall of the second flow channel is b, bgt; a. Compared with a traditional technical scheme, the width of the bottom wall of the second flow channel does not need to be changed, that is, limitation of the width of the polar plate is not needed, and the flow area of the second flow channel can be increased, the pressure drop proportion of the activation area can be reduced and the pressure drop proportion of the distribution area can be increased only by increasing the included angle between the bottom wall and the side wall of the second flow channel.

Description

Technical Field

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

[0002] A bipolar plate generally includes a distribution area and an activation area. A plurality of first flow channels are provided in the distribution area, and a plurality of second flow channels are provided in the activation area. Each first flow channel is respectively communicated with a plurality of second flow channels for fluid circulation. The included angle between the bottom wall and the side wall of the first flow channel is equal to the included angle between the bottom wall and the side wall of the second flow channel, and in the first flow channel and the corresponding plurality of second flow channels, the left side wall of the first flow channel is connected to the left side wall of one of the second flow channels, and the right side wall of the first flow channel is connected to the right side wall of another second flow channel.

[0003] Factors such as the size of the outlet of the second flow channel, the pressure drop ratio of the distribution area and the activation area, etc. will affect the uniformity of fluid flow in the second flow channel. The smaller the proportion of the pressure drop in the activation area and the larger the proportion of the pressure drop in the distribution area, the better the uniformity of fluid flow in the activation area.

[0004] In the prior art, usually, the width of the bottom wall of the second flow channel is adjusted to increase the flow area of the second flow channel, and the purpose of reducing the proportion of the pressure drop in the activation area and increasing the proportion of the pressure drop in the distribution area is achieved. However, affected by the width of the bipolar plate and the requirements of the flow channels, the width of the bottom wall of the second flow channel cannot be overly enlarged. By adjusting the width of the bottom wall of the second flow channel to reduce the proportion of the pressure drop in the activation area, the improvement effect on the uniformity of fluid flow in the activation area is limited. Summary of the Invention

[0005] The present invention provides a bipolar plate, a fuel cell stack, and a fuel cell to solve the problem in the prior art that affected by the width of the bipolar plate and the requirements of the flow channels, increasing the width of the bottom wall of the flow channels in the activation area to reduce the proportion of the pressure drop in the activation area has limited effect.

[0006] According to one aspect of the present invention, a bipolar plate is provided, which includes a distribution area and an activation area that are communicated with each other. A plurality of spaced-apart first flow channels are provided in the distribution area, and a plurality of spaced-apart second flow channels are provided in the activation area. The plurality of first flow channels are communicated with the plurality of second flow channels for fluid circulation. The included angle between the side wall and the bottom wall of the first flow channel is a, and the included angle between the side wall and the bottom wall of the second flow channel is b, and b > a.

[0007] Further, 0° < b - a ≤ 45°.

[0008] Further, the first flow channel includes a first side wall and a second side wall that are oppositely arranged, and the distance between the first side wall and the second side wall gradually increases in a direction away from the bottom wall of the first flow channel.

[0009] Furthermore, the angle between the first side wall of the first flow channel and the bottom wall of the first flow channel is a1, 90°≤a1<135°; the angle between the second side wall of the first flow channel and the bottom wall of the first flow channel is a2, 90°≤a2<135°.

[0010] Further, the second flow channel includes a third side wall and a fourth side wall that are arranged opposite to each other, and the distance between the third side wall and the fourth side wall gradually increases toward a direction away from the bottom wall of the second flow channel.

[0011] Furthermore, the angle between the third side wall of the second flow channel and the bottom wall of the second flow channel is b1, 90°<b1≤135°; the angle between the third side wall of the second flow channel and the bottom wall of the second flow channel is b2, 90°<b2≤135°.

[0012] Furthermore, the first flow channel includes a main flow channel and a transition flow channel that are interconnected, one end of the transition flow channel is connected to the main flow channel, and the other end of the transition flow channel is connected to the second flow channel, and the angle between the side wall of the transition flow channel and the bottom wall of the transition flow channel gradually increases in the direction away from the main flow channel.

[0013] Furthermore, the number of the first flow channels is less than the number of the second flow channels, and each first flow channel is connected to 2 to 6 second flow channels respectively.

[0014] According to another aspect of the present invention, a fuel cell stack is provided, comprising the above-mentioned electrode plate.

[0015] According to another aspect of the present invention, a fuel cell is provided, comprising the above-mentioned electrode plate.

[0016] By applying the technical solution of the present invention, the angle between the side wall and the bottom wall of the second flow channel in the activation zone is greater than the angle between the side wall and the bottom wall of the first flow channel in the distribution zone. With such a setting, the design of the second flow channel does not need to consider the width of the electrode plate, and can reduce the pressure drop ratio of the activation zone as much as possible, increase the pressure drop ratio of the distribution zone, and achieve the effect of improving the uniformity of the flow of the fluid in the activation zone. In the traditional technical solution, the flow area of ​​the flow channel in the activation zone is increased by increasing the width of the bottom wall of the flow channel in the activation zone, and the pressure drop ratio of the activation zone is reduced. However, considering the width of the entire plate and the number of flow channels in the activation zone, the width of the bottom wall of the flow channel in the activation zone cannot be excessively enlarged, and the effect of reducing the pressure drop ratio of the activation zone by the traditional technical solution is limited. Compared with the traditional technical solution, the setting of this solution does not need to change the width of the bottom wall of the second flow channel, and adjusts the flow area of ​​the second flow channel by the angle between the bottom wall and the side wall of the second flow channel, reduces the pressure drop ratio of the activation zone, and increases the pressure drop ratio of the distribution zone, without being limited by the width of the electrode plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 shows a schematic structural view of a plate electrode provided according to an embodiment of the present invention;

[0019] Figure 2 shows a schematic structural view intended to show the second flow channel;

[0020] Figure 3 shows a schematic structural view intended to show the first flow channel;

[0021] Figure 4 shows a schematic partial structural view of a plate electrode provided according to an embodiment of the present invention.

[0022] Among them, the above-mentioned drawings include the following reference numerals:

[0023] 01, distribution area; 011, inlet distribution area; 012, outlet distribution area;

[0024] 02, activation area;

[0025] 031, inlet manifold area; 032, outlet manifold area;

[0026] 10, first flow channel;

[0027] 101, first side wall; 102, second side wall;

[0028] 11, main flow channel; 12, transition flow channel;

[0029] 20, second flow channel; 201, third side wall; 202, fourth side wall. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way constitutes a limitation on the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] Such as Figures 1 to 4As shown, the first embodiment of the present invention provides a plate, which includes a manifold area, a distribution area 01 and an activation area 02. The manifold area includes an inlet manifold area 031 and an outlet manifold area 032, and the distribution area 01 includes an inlet distribution area 011 and an outlet distribution area 012. Along the extension direction of the plate, the inlet manifold area 031, the inlet distribution area 011, the activation area 02, the outlet distribution area 012 and the outlet manifold area 032 are connected in sequence. A plurality of first flow channels 10 distributed at intervals are arranged in the distribution area 01, and a plurality of second flow channels 20 distributed at intervals are arranged in the activation area 02. The plurality of first flow channels 10 are connected with the plurality of second flow channels 20 for fluid circulation, and the angle between the side wall of the first flow channel 10 and the bottom wall of the first flow channel 10 is a, and the angle between the side wall of the second flow channel 20 and the bottom wall of the second flow channel 20 is b, and b>a.

[0032] In this solution, the inlet distribution area 011 is provided with a plurality of first flow channels 10, and the outlet distribution area 012 is provided with a plurality of first flow channels 10. The plurality of first flow channels 10 in the inlet distribution area 011 are respectively connected with the plurality of second flow channels 20, and the plurality of first flow channels 10 in the outlet distribution area 012 are respectively connected with the plurality of second flow channels 20.

[0033] By applying the technical solution of the present invention, the angle between the side wall and the bottom wall of the second flow channel 20 in the activation zone 02 is greater than the angle between the side wall and the bottom wall of the first flow channel 10 in the distribution zone 01. With such a configuration, the design of the second flow channel 20 does not need to consider the width of the electrode plate, and can reduce the pressure drop ratio of the activation zone 02 as much as possible, increase the pressure drop ratio of the distribution zone 01, and achieve the effect of improving the uniformity of the flow of the fluid in the activation zone 02. In the traditional technical solution, the flow area of ​​the flow channel in the activation zone is increased by increasing the width of the bottom wall of the flow channel in the activation zone, and the pressure drop ratio of the activation zone is reduced. However, considering the width of the electrode plate and the number of flow channels in the activation zone, the width of the bottom wall of the flow channel in the activation zone cannot be excessively enlarged, and the effect of reducing the pressure drop ratio of the activation zone by the traditional technical solution is limited. In addition, in the traditional technical solution, the width of the bottom wall of the flow channel in the activation zone is increased, which will correspondingly reduce the number of flow channels in the activation zone, which is not conducive to the uniformity of fluid distribution. Compared with the traditional technical solutions, the setting of this solution does not need to change the width of the bottom wall of the second flow channel 20. The flow area of ​​the second flow channel 20 is adjusted by the angle between the bottom wall and the side wall of the second flow channel 20, thereby reducing the pressure drop ratio of the activation area 02 and increasing the pressure drop ratio of the distribution area 01, without considering the width of the electrode plate.

[0034] In the embodiment of the present solution, 0°<ba≤45°. When ba>45°, it is not convenient to process the electrode plate.

[0035] In the embodiments of this solution, it can be set that b - a = 5°, b - a = 10°, b - a = 15°, b - a = 20° or b - a = 45°. As long as it is ensured that b - a ≤ 45°.

[0036] Further, the first flow channel 10 includes a first side wall 101 and a second side wall 102 which are oppositely arranged, and the distance between the first side wall 101 and the second side wall 102 gradually increases in the direction away from the bottom wall of the first flow channel 10. With such a setting, the cross-sectional area of the first flow channel 10 can be increased as much as possible, the pressure drop ratio of the activation region 02 can be reduced, and the uniformity and smoothness of fluid flow can be improved.

[0037] Specifically, the included angle between the first side wall 101 of the first flow channel 10 and the bottom wall of the first flow channel 10 is a1, 90° ≤ a1 < 135°; the included angle between the second side wall 102 of the first flow channel 10 and the bottom wall of the first flow channel 10 is a2, 90° ≤ a2 < 135°. With the above settings, the included angle between the first side wall 101 of the first flow channel 10 and the bottom wall of the first flow channel 10 is a right angle or an obtuse angle, and the included angle between the second side wall 102 of the first flow channel 10 and the bottom wall of the first flow channel 10 is a right angle or an obtuse angle, which can improve the smoothness of fluid flow in the first flow channel 10 and ensure the convenience of processing the electrode plate.

[0038] In this embodiment, both the first side wall 101 and the second side wall 102 are inclined. With such a setting, the convenience of processing the first flow channel 10 can be improved, and the smoothness of fluid flow can be ensured.

[0039] Specifically, the second flow channel 20 includes a third side wall 201 and a fourth side wall 202 which are oppositely arranged, and the distance between the third side wall 201 and the fourth side wall 202 gradually increases in the direction away from the bottom wall of the second flow channel 20. With such a setting, the cross-sectional area of the second flow channel 20 can be increased as much as possible, and the smoothness of fluid flow can be improved.

[0040] Specifically, the included angle between the third side wall 201 of the second flow channel 20 and the bottom wall of the second flow channel 20 is b1, 90° < b1 ≤ 135°; the included angle between the third side wall 201 of the second flow channel 20 and the bottom wall of the second flow channel 20 is b2, 90° < b2 ≤ 135°.

[0041] In this embodiment, both the third side wall 201 and the fourth side wall 202 are inclined, and b1 = b2. With such a setting, the convenience of processing the second flow channel 20 can be improved, and the smoothness of fluid flow can be ensured.

[0042] In this solution, the first flow channel 10 includes a main flow channel 11 and a transition flow channel 12 that are interconnected. One end of the transition flow channel 12 is connected to the main flow channel 11, and the other end of the transition flow channel 12 is connected to the second flow channel 20. The angle between the side wall and the bottom wall of the transition flow channel 12 gradually increases in the direction away from the main flow channel 11. The setting of the transition flow channel 12 can play a buffering role and avoid the situation where the cross-sectional area of the flow channel suddenly changes during the process of the fluid flowing from the main flow channel 11 to the second flow channel 20, enabling the fluid to flow smoothly from the distribution area 01 to the activation area 02, further improving the smoothness of fluid flow and the uniformity of flow within the activation area 02.

[0043] In this embodiment, the angle between the bottom wall and the first side wall 101 of the main flow channel 11 in the inlet distribution area 011 is 110°, and the angle between the bottom wall and the second side wall 102 of the main flow channel 11 in the inlet distribution area 011 is 110°. The angle between the bottom wall and the first side wall 101 of the main flow channel 11 in the outlet distribution area 012 is 110°, and the angle between the bottom wall and the second side wall 102 of the main flow channel 11 in the outlet distribution area 012 is 110°. The angle between the bottom wall and the third side wall 201 of the second flow channel 20 is 120°, and the angle between the bottom wall and the fourth side wall 202 of the second flow channel 20 is 120°.

[0044] In this solution, the number of the first flow channels 10 is less than the number of the second flow channels 20, and each first flow channel 10 is respectively connected to 2 to 6 second flow channels 20. In this embodiment, the multiple second flow channels 20 are equally spaced along the width direction of the electrode plate, and the extending direction of the second flow channel 20 is the same as the extending direction of the electrode plate, that is, adjacent two second flow channels 20 are equally spaced. Such a setting enables the fluid in the first flow channel 10 to be divided into 2 to 6 parts and flow into different second flow channels 20 respectively, further improving the uniformity of fluid flow within the activation area 02.

[0045] Further, among each first flow channel 10 and the corresponding multiple second flow channels 20, the first side wall 101 of the first flow channel 10 is connected to the third side wall 201 of one of the outermost second flow channels 20, and the second side wall 102 of the first flow channel 10 is connected to the fourth side wall 202 of the other outermost second flow channel 20. Such a setting can improve the smoothness of the fluid flowing from the distribution area 01 to the activation area 02.

[0046] Embodiment II of the present invention provides a stack, which includes the above-mentioned electrode plate.

[0047] Embodiment III of the present invention provides a fuel cell, which includes the above-mentioned electrode plate.

[0048] Note that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprises" and / or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and / or combinations thereof.

[0049] Unless otherwise specifically stated, the relative arrangements of the components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the specification. In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof is not required in subsequent drawings.

[0050] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0051] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper", etc. can be used here to describe the spatial positional relationship of a device or feature shown in the figure with other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is inverted, the device described as "above" or "over" other devices or structures will then be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the corresponding explanations for the spatial relative descriptions used here will be made accordingly.

[0052] In addition, it should be noted that the use of terms such as "first", "second", etc. to limit components is only for the convenience of differentiating the corresponding components. Without additional statements, the above terms have no special meanings, and thus cannot be construed as limiting the protection scope of the present invention.

[0053] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A plate, It is characterized in that The invention comprises a distribution area (01) and an activation area (02) which are interconnected, wherein a plurality of first flow channels (10) are arranged in the distribution area (01), and a plurality of second flow channels (20) are arranged in the activation area (02), wherein the plurality of first flow channels (10) are connected to the plurality of second flow channels (20) for fluid circulation, wherein the angle between the side wall of the first flow channel (10) and the bottom wall of the first flow channel (10) is a, and the angle between the side wall of the second flow channel (20) and the bottom wall of the second flow channel (20) is b, and b>a.

2. The electrode plate according to claim 1, It is characterized in that 0°<ba≤45°.

3. The electrode plate according to claim 1, It is characterized in that The first flow channel (10) comprises a first side wall (101) and a second side wall (102) which are arranged opposite to each other, and the distance between the first side wall (101) and the second side wall (102) gradually increases in a direction away from the bottom wall of the first flow channel (10).

4. The electrode plate according to claim 3, It is characterized in that The included angle between the first side wall (101) of the first flow channel (10) and the bottom wall of the first flow channel (10) is a1, 90°≤a1<135°; The included angle between the second side wall (102) of the first flow channel (10) and the bottom wall of the first flow channel (10) is a2, and 90°≤a2<135°.

5. The electrode plate according to claim 1, It is characterized in that The second flow channel (20) comprises a third side wall (201) and a fourth side wall (202) which are arranged opposite to each other, and the distance between the third side wall (201) and the fourth side wall (202) gradually increases in a direction away from the bottom wall of the second flow channel (20).

6. The electrode plate according to claim 5, It is characterized in that The included angle between the third side wall (201) of the second flow channel (20) and the bottom wall of the second flow channel (20) is b1, 90°<b1≤135°; The included angle between the third side wall (201) of the second flow channel (20) and the bottom wall of the second flow channel (20) is b2, 90°<b2≤135°.

7. The electrode plate according to claim 1, It is characterized in that The first flow channel (10) comprises a main flow channel (11) and a transition flow channel (12) which are connected to each other, one end of the transition flow channel (12) is connected to the main flow channel (11), and the other end of the transition flow channel (12) is connected to the second flow channel (20), and the angle between the side wall of the transition flow channel (12) and the bottom wall of the transition flow channel (12) gradually increases in a direction away from the main flow channel (11).

8. The electrode plate according to claim 1, It is characterized in that The number of the first flow channels (10) is less than the number of the second flow channels (20), and each of the first flow channels (10) is respectively connected to 2 to 6 of the second flow channels (20).

9. A battery stack, It is characterized in that The electrode plate comprises the electrode plate according to any one of claims 1 to 8.

10. A fuel cell, It is characterized in that The electrode plate comprises the electrode plate according to any one of claims 1 to 8.

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