PEM hydrogen production flow field bipolar plate, hydrogen production galvanic pile and hydrogen production method thereof

Abstract

The invention discloses a PEM hydrogen production flow field bipolar plate, a hydrogen production galvanic pile and a hydrogen production method of the PEM hydrogen production flow field bipolar plate. The PEM hydrogen production flow field bipolar plate comprises a bipolar plate body, an oxygen flow channel and a hydrogen flow channel, the oxygen flow channel and the hydrogen flow channel are respectively arranged on two opposite surfaces of the bipolar plate body; the oxygen flow channel is used for introducing electrolyzed water and forming turbulent flow to promote electrolytic reaction, and the hydrogen flow channel is used for guiding generated hydrogen to be rapidly output. According to the invention, the contact efficiency of electrolyzed water and the proton exchange membrane can be improved, the electrolytic reaction is promoted, and rapid output of hydrogen is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production equipment, and particularly to a PEM hydrogen production flow field bipolar plate, a hydrogen production stack and a hydrogen production method thereof. Background Art

[0002] At present, the flow field design in PEM (Proton exchange membrane) hydrogen production technology directly affects the hydrogen production efficiency. The existing PEM hydrogen production flow field bipolar plates mainly adopt structures such as parallel flow channels and serpentine flow channels. These flow field structures have the following problems: When electrolyzed water flows in the flow channel, it is easy to form laminar flow, resulting in insufficient contact with the surface of the proton exchange membrane and reducing the reaction efficiency; the pressure distribution in the flow channel is uneven, making the electrolysis reaction in some areas insufficient; the accumulation of hydrogen in the flow channel will hinder the contact between electrolyzed water and the proton exchange membrane. In addition, in the traditional flow field structure, the contact area between electrolyzed water and the reaction surface is limited, and the residence time of electrolyzed water on the reaction surface is short, which is not conducive to improving the hydrogen production efficiency. In terms of hydrogen collection, the existing flow channel structure is also difficult to achieve the rapid output of hydrogen, resulting in the accumulation of hydrogen in the flow channel and further affecting the hydrogen production efficiency. These problems seriously restrict the performance improvement of the PEM hydrogen production system.

[0003] Therefore, there is an urgent need to propose a PEM hydrogen production flow field bipolar plate, a hydrogen production stack and a hydrogen production method thereof to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to propose a PEM hydrogen production flow field bipolar plate, a hydrogen production stack and a hydrogen production method thereof, which can improve the contact efficiency between electrolyzed water and the proton exchange membrane, promote the electrolysis reaction, and achieve the rapid output of hydrogen.

[0005] To solve the above technical problems, the present invention provides a PEM hydrogen production flow field bipolar plate, including a bipolar plate body, an oxygen flow channel and a hydrogen flow channel;

[0006] The oxygen flow channel and the hydrogen flow channel are respectively arranged on two opposite surfaces of the bipolar plate body; the oxygen flow channel is used for introducing electrolyzed water and forming turbulent flow to promote the electrolysis reaction, and the hydrogen flow channel is used for guiding the generated hydrogen to be rapidly output.

[0007] Further, the oxygen flow channel includes a plurality of serrated flow channels and ridges arranged between two adjacent serrated flow channels; two adjacent serrated flow channels are symmetrically arranged, and the ridge is formed between two adjacent serrated flow channels.

[0008] Further, the serrated flow channel includes a pair of parallel and staggered serrated curves; the serrated curve includes a plurality of first straight line segments and second straight line segments;

[0009] Both ends of the second straight-line segment are respectively connected to two adjacent first straight-line segments; the ends of two first straight-line segments that are adjacent and connected to different second straight-line segments and are far away from the second straight-line segments are connected and form a first included angle; the first straight-line segment and the second straight-line segment form a second included angle.

[0010] Furthermore, for each of the serrated channels, the first included angle of one of the serrated curves is arranged corresponding to the position of the second included angle of the other serrated curve.

[0011] Furthermore, the width range of the serrated channel is between 1 - 2 mm.

[0012] Furthermore, the width range of the ridge is between 1.5 - 3.5 mm.

[0013] Furthermore, the hydrogen flow channel includes a plurality of circular island ridges that are dispersedly arranged; the diameter range of the circular island ridges is between 2 - 3 mm.

[0014] In addition, the present invention also provides a hydrogen production stack, which includes the PEM hydrogen production flow field bipolar plate as described above, and also includes a gasket, carbon paper, and a proton exchange membrane;

[0015] A part of the proton exchange membrane is provided with the carbon paper, and the carbon paper is arranged on both sides of the proton exchange membrane; another part of the proton exchange membrane is provided with the gasket, and the gasket is arranged on both sides of the proton exchange membrane; a part of the proton exchange membrane corresponds to the oxygen flow channel or the hydrogen flow channel in the PEM hydrogen production flow field bipolar plate.

[0016] In addition, the present invention also provides a hydrogen production method, which uses the PEM hydrogen production flow field bipolar plate as described above, or uses the hydrogen production stack as described above, and specifically includes the following:

[0017] Inject electrolyzed water into the oxygen flow channel;

[0018] Apply a voltage across the two poles of the PEM hydrogen production flow field bipolar plate to cause the electrolyzed water to undergo an electrolysis reaction on the surface of the proton exchange membrane, generating hydrogen and oxygen;

[0019] Output hydrogen through the self-selective pressure drop flow channel formed between the multiple circular island ridges of the hydrogen flow channel.

[0020] Furthermore, it further includes: during the process of the electrolyzed water passing through the serrated channel of the oxygen flow channel, controlling the flow rate of the electrolyzed water so that a directional turbulent flow is formed at the connection of the first straight-line segment and the second straight-line segment in the oxygen flow channel.

[0021] Through the above technical solutions, the present invention has the following beneficial effects:

[0022] Through the settings of the bipolar plate body, oxygen flow channels, and hydrogen flow channels; and the oxygen flow channels and hydrogen flow channels are respectively arranged on two opposite faces of the bipolar plate body; the oxygen flow channels are used to introduce electrolyzed water and form turbulent flow to promote the electrolysis reaction, and the hydrogen flow channels are used to guide the generated hydrogen to be quickly output. The present invention can improve the contact efficiency between the electrolyzed water and the proton exchange membrane, promote the progress of the electrolysis reaction, and achieve the quick output of hydrogen.

[0023] In addition, by setting serrated flow channels at a specific angle in the oxygen flow channels, the electrolyzed water forms directional turbulent flow at the connection of the first straight section and the second straight section, which can enhance the contact between the electrolyzed water and the proton exchange membrane, thereby improving the reaction efficiency. And by setting ridges between adjacent serrated flow channels, the stability of the flow channel structure can be ensured, and local deformation can also be avoided.

[0024] Furthermore, by setting dispersed circular island ridges in the hydrogen flow channels to form a self-selective pressure drop flow channel, the quick output of hydrogen is realized, and the accumulation of hydrogen in the flow channels is prevented. The present invention ensures the overall performance of the flow field structure by reasonably setting the sizes of the flow channels and the ridges. Description of the Drawings

[0025] Figure 1 It is a schematic diagram of the overall structure of the PEM hydrogen production flow field bipolar plate in an embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the structure of the oxygen flow channels in the PEM hydrogen production flow field bipolar plate in an embodiment of the present invention;

[0027] Figure 3 It is a schematic diagram of the structure of the hydrogen flow channels in the PEM hydrogen production flow field bipolar plate in an embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of the structure of the oxygen flow channels on the bipolar plate body in the PEM hydrogen production flow field bipolar plate in an embodiment of the present invention;

[0029] Figure 5 It is a schematic diagram of the structure of the hydrogen flow channels on the bipolar plate body in the PEM hydrogen production flow field bipolar plate in an embodiment of the present invention;

[0030] Figure 6 It is a schematic diagram of the overall structure of the hydrogen production stack in an embodiment of the present invention;

[0031] Figure 7 It is a flowchart of the hydrogen production method in an embodiment of the present invention.

[0032] In the figure, 1 is the bipolar plate body; 2 is the oxygen flow channel; 21 is the serrated flow channel; 211 is the first straight segment; 212 is the second straight segment; 213 is the first included angle; 214 is the second included angle; 22 is the ridge; 3 is the hydrogen flow channel; 31 is the circular island ridge; 4 is the gasket; 5 is the carbon paper; 6 is the proton exchange membrane. Detailed implementation mode

[0033] The following will describe a PEM hydrogen production flow field bipolar plate, a hydrogen production stack and a hydrogen production method of the present invention in more detail with reference to the accompanying drawings, in which the preferred embodiments of the present invention are shown. It should be understood that those skilled in the art can modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as a broad guidance for those skilled in the art and not as a limitation of the present invention.

[0034] In the following paragraphs, the present invention will be described more specifically by way of example with reference to the accompanying drawings. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0035] As shown in Figure 1 the figure, an embodiment of the present invention provides a PEM hydrogen production flow field bipolar plate, which includes a bipolar plate body 1, an oxygen flow channel 2 and a hydrogen flow channel 3.

[0036] Specifically, the oxygen flow channel 2 and the hydrogen flow channel 3 are respectively arranged on two opposite surfaces of the bipolar plate body 1; the oxygen flow channel 2 is used to introduce electrolyzed water and form a turbulent flow to promote the electrolysis reaction, and the hydrogen flow channel 3 is used to guide the generated hydrogen to be quickly output. In this embodiment, by separately arranging the oxygen flow channel 2 and the hydrogen flow channel 3, the contact area between the electrolyzed water and the proton exchange membrane 6 is increased, and the electrolysis efficiency is improved.

[0037] As a preferred embodiment, as shown in Figure 2 and Figure 4 the figure, the oxygen flow channel 2 includes a plurality of serrated flow channels 21 and a ridge 22 arranged between two adjacent serrated flow channels 21. Specifically, two adjacent serrated flow channels 21 are symmetrically arranged, and the ridge 22 is formed between two adjacent serrated flow channels 21. The zigzag setting of this embodiment can enhance the flow guiding effect of the flow field structure and improve the turbulence degree of the electrolyzed water.

[0038] In one embodiment, the serrated flow channel 21 includes a pair of serrated curves arranged in parallel and staggered; the serrated curve includes a plurality of first straight segments 211 and second straight segments 212.

[0039] Specifically, both ends of the second straight segment 212 are respectively connected to two adjacent first straight segments 211; the ends of two first straight segments 211 that are adjacent and connected to different second straight segments 212 and are away from the second straight segments 212 are connected, and form a first included angle 213; the first straight segment 211 and the second straight segment 212 form a second included angle 214. This can enhance the turbulence intensity of the electrolyzed water in the flow channel.

[0040] Further, a third straight segment (the size can be set according to actual requirements) may be included between the first straight segment 211 and the second straight segment 212. By introducing the third straight segment, a stepped transition structure is formed between the first straight segment 211 and the second straight segment 212, so that the second included angle 214 changes from a sharp turn to a more gentle stepped turn. This structural design can reduce the resistance loss of the electrolyzed water during turning, and at the same time maintain an appropriate turbulence effect, which is beneficial to improving the overall performance of the flow field.

[0041] In this embodiment, the first included angle 213 of one of the sawtooth curves in each sawtooth flow channel 21 is set corresponding to the second included angle 214 of the other sawtooth curve. Through this corresponding setting, the uniformity of the turbulence in the flow channel can be improved. In a specific example, the number of zigzags of the sawtooth curve is, for example, 8 - 12 times, and this setting can increase the contact time between the electrolyzed water and the proton exchange membrane 6.

[0042] In this embodiment, the first included angle 213 may be equal to the second included angle 214. For example, both the first included angle 213 and the second included angle 214 are 120 degrees. This angle design can enhance the turbulence effect of the electrolyzed water at the turning of the flow channel. Those skilled in the art know that the size of the included angle can be set according to actual requirements.

[0043] In one embodiment, the width range of the sawtooth flow channel 21 is between 1 - 2 mm; the width range of the ridge 22 is between 1.5 - 3.5 mm. Those skilled in the art know that the widths of the flow channel and the ridge 22 can be set according to actual requirements, and there are also other embodiments besides this embodiment.

[0044] As a preferred embodiment, in combination with Figure 3 and Figure 5 as shown, the hydrogen flow channel 3 includes a plurality of circular island ridges 31 that are dispersedly arranged; the diameter range of the circular island ridges 31 is between 2 - 3 mm. Specifically, the circular island ridges 31 are arranged in an array, and the spacing between adjacent circular island ridges 31 can be set according to actual requirements. The setting of the circular island ridges 31 forms a self - selective pressure - drop flow channel, thereby being able to improve the output efficiency of hydrogen.

[0045] In addition, in combination withFigures 4 - 6 This embodiment also provides a hydrogen production stack, including the PEM hydrogen production flow field bipolar plate as described above, and also including a sealing gasket 4, a carbon paper 5 and a proton exchange membrane 6.

[0046] Specifically, a portion of the proton exchange membrane 6 is provided with the carbon paper 5, and the carbon paper 5 is provided on both sides of the proton exchange membrane 6; another portion of the proton exchange membrane 6 is provided with the sealing gasket 4, and the sealing gasket 4 is provided on both sides of the proton exchange membrane 6; a portion of the proton exchange membrane 6 corresponds to the oxygen flow channel 2 or the hydrogen flow channel 3 in the PEM hydrogen production flow field bipolar plate. This structural setting can improve the overall sealing performance and reaction efficiency of the stack.

[0047] In addition, if Figure 7 As shown, this embodiment also proposes a hydrogen production method, using the PEM hydrogen production flow field bipolar plate as described above, or using the hydrogen production stack as described above, specifically including the following steps:

[0048] S1, introducing electrolyzed water into oxygen flow channel 2;

[0049] S2, applying voltage to the two electrodes of the bipolar plate of the PEM hydrogen production flow field, so that the electrolyzed water undergoes an electrolysis reaction on the surface of the proton exchange membrane 6 to produce hydrogen and oxygen; and

[0050] S3 , outputting hydrogen through the self-selective pressure drop channel formed between the multiple circular island ridges 31 of the hydrogen channel 3 .

[0051] In addition, this embodiment also includes: in step S2, during the process of the electrolyzed water passing through the serrated channel 21 of the oxygen channel 2, the flow rate of the electrolyzed water is controlled so that directional turbulence is formed at the connection between the first straight segment 211 and the second straight segment 212 in the oxygen channel 2.

[0052] In this embodiment, the working process of PEM hydrogen production is exactly the opposite of that of fuel cells. Hydrogen flow channels 3 and oxygen flow channels 2 are respectively arranged on two opposite sides of the bipolar plate. Unlike the traditional fuel cell structure, no cooling flow channels are required. Oxygen flow channels 2 have dual functions: on the one hand, they are used to provide electrolyzed water, and on the other hand, they have heat transfer and heat dissipation functions, which can take away the reaction heat during operation, or introduce preheated electrolyzed water into the flow channel during low-temperature startup to provide the required reaction temperature.

[0053] For the hydrogen flow channel 3, since the PEM hydrogen production process only needs to output the generated hydrogen quickly, there is no need to transport the hydrogen to the surface of the proton exchange membrane 6 to participate in the reaction like a fuel cell. Therefore, the circular island ridge 31 used in this embodiment provides necessary mechanical support for the proton exchange membrane 6 and the diffusion layer carbon paper 5, and provides a smooth channel for hydrogen output.

[0054] For the oxygen flow channel 2, its working characteristic is that it needs to continuously supplement electrolyzed water for electrolysis reaction, and at the same time carry and discharge the generated oxygen out of the flow channel. In this embodiment, through the setting of the serrated flow channel 21, turbulence is formed during the flow of electrolyzed water, promoting the more sufficient contact between the electrolyzed water and the surface of the proton exchange membrane 6, thereby improving the electrolysis reaction efficiency.

[0055] In this embodiment, the electrolyzed water enters through the oxygen flow channel 2, forms a directional turbulence at the turning point of the serrated flow channel 21, enhances the contact with the proton exchange membrane 6, and promotes the electrolysis reaction. When the electrolyzed water flows in the first straight section 211, due to the angle formed with the second straight section 212, a centrifugal force is generated at the turning point, forming local turbulence. When the electrolyzed water flows through the second straight section 212, due to the turning effect of the flow channel, the turbulence effect is further enhanced. The generated hydrogen is quickly output through the self-selective pressure drop flow channel formed between the circular ridges 31 in the hydrogen flow channel 3, avoiding hydrogen accumulation. The setting of the circular ridges 31 forms multiple parallel output channels during the flow of hydrogen, improving the hydrogen output efficiency.

[0056] As is known to those skilled in the art, the working temperature range of this embodiment can be set according to actual needs, the working pressure range can be set according to actual needs, and the flow rate range of the electrolyzed water can be set according to actual needs. The setting of these parameters can further optimize the hydrogen production efficiency.

[0057] In summary, a PEM hydrogen production flow field bipolar plate, a hydrogen production stack and a hydrogen production method proposed by the present invention have the following advantages:

[0058] Through the setting of the bipolar plate body, the oxygen flow channel and the hydrogen flow channel; and the oxygen flow channel and the hydrogen flow channel are respectively arranged on two opposite surfaces of the bipolar plate body; the oxygen flow channel is used to introduce electrolyzed water and form turbulence to promote the electrolysis reaction, and the hydrogen flow channel is used to guide the generated hydrogen to be quickly output. The present invention can improve the contact efficiency between the electrolyzed water and the proton exchange membrane, promote the electrolysis reaction, and realize the quick output of hydrogen.

[0059] In addition, by setting a serrated flow channel with a specific angle in the oxygen flow channel, a directional turbulence is formed at the connection of the first straight section and the second straight section of the electrolyzed water, which can enhance the contact between the electrolyzed water and the proton exchange membrane, thereby improving the reaction efficiency. And by setting ridges between adjacent serrated flow channels, the stability of the flow channel structure can be ensured, and local deformation can also be avoided.

[0060] In addition, by setting dispersed circular ridges in the hydrogen flow channel to form a self-selective pressure drop flow channel, the quick output of hydrogen is realized, preventing hydrogen from accumulating in the flow channel. The present invention ensures the overall performance of the flow field structure by reasonably setting the sizes of the flow channels and the ridges.

[0061] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A PEM hydrogen production flow field bipolar plate, characterized in that: It includes a bipolar plate body, an oxygen flow channel and a hydrogen flow channel; The oxygen flow channel and the hydrogen flow channel are respectively arranged on two opposite surfaces of the bipolar plate body; the oxygen flow channel is used to pass electrolytic water and form turbulence to promote the electrolysis reaction, and the hydrogen flow channel is used to guide the generated hydrogen to be quickly output.

2. The PEM hydrogen production flow field bipolar plate according to claim 1, characterized in that: The oxygen flow channel comprises a plurality of sawtooth flow channels and a ridge portion arranged between two adjacent sawtooth flow channels; the two adjacent sawtooth flow channels are arranged symmetrically, and the ridge portion is formed between the two adjacent sawtooth flow channels.

3. The PEM hydrogen production flow field bipolar plate according to claim 2, characterized in that: The sawtooth flow channel comprises a pair of parallel and staggered sawtooth curves; the sawtooth curve comprises a plurality of first straight line segments and second straight line segments; Both ends of the second straight line segment are respectively connected to two adjacent first straight line segments; two adjacent first straight line segments connected to different second straight line segments are connected at one end away from the second straight line segment and form a first angle; the first straight line segment and the second straight line segment form a second angle.

4. The PEM hydrogen production flow field bipolar plate according to claim 3, characterized in that: The first angle of one of the sawtooth curves in each of the sawtooth flow channels is arranged correspondingly to the second angle of another of the sawtooth curves.

5. The PEM hydrogen production flow field bipolar plate according to claim 3, characterized in that: The width of the serrated flow channel ranges from 1 to 2 mm.

6. The PEM hydrogen production flow field bipolar plate according to claim 2, characterized in that: The width of the ridge ranges from 1.5 to 3.5 mm.

7. The PEM hydrogen production flow field bipolar plate according to claim 1, characterized in that: The hydrogen flow channel includes a plurality of dispersed circular island ridges; the diameter of the circular island ridges ranges from 2 to 3 mm.

8. A hydrogen production stack, comprising the PEM hydrogen production flow field bipolar plate according to any one of claims 1 to 7, characterized in that: Also included are sealing gaskets, carbon paper, and proton exchange membranes; The carbon paper is provided in a portion of the proton exchange membrane, and the carbon paper is provided on both sides of the proton exchange membrane; the sealing gasket is provided in another portion of the proton exchange membrane, and the sealing gasket is provided on both sides of the proton exchange membrane; a portion of the proton exchange membrane corresponds to the oxygen flow channel or the hydrogen flow channel in the PEM hydrogen production flow field bipolar plate.

9. A method for producing hydrogen, using the PEM hydrogen production flow field bipolar plate according to any one of claims 1 to 7, or using the hydrogen production stack according to claim 8, characterized in that: The details include: Passing electrolyzed water into the oxygen flow channel; Applying voltage to the two electrodes of the bipolar plate of the PEM hydrogen production flow field causes the electrolyzed water to undergo an electrolysis reaction on the surface of the proton exchange membrane to generate hydrogen and oxygen; The hydrogen gas is output through a self-selected pressure drop flow channel formed between a plurality of circular island ridges of the hydrogen flow channel.

10. The method for producing hydrogen according to claim 9, characterized in that: Also includes: When the electrolyzed water passes through the zigzag flow channel of the oxygen flow channel, the flow rate of the electrolyzed water is controlled to form a directional turbulence at the connection between the first straight line segment and the second straight line segment in the oxygen flow channel.

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