PEM water electrolyser anode composite flow field plate

Abstract

The utility model relates to the technical field of PEM water electrolyser anode flow field plates, in particular to a PEM water electrolyser anode composite flow field plate, which comprises a flow field inlet, the main flow area is communicated with the flow field inlet and comprises a plurality of parallel first flow channels; the downstream permeation strengthening area comprises a plurality of parallel second flow channels, and the second flow channels are used for strengthening local permeation; the second flow channel is communicated with the first flow channel, and the flow channel type of the second flow channel is different from that of the first flow channel; the flow field outlet is communicated with the second flow channel of the downstream permeation strengthening area; raw materials flow in the sequence of the flow field inlet, the first flow channel, the second flow channel and the flow field outlet. Different flow channel types can be adopted in the area close to the outlet, so that raw material water permeation of the area is enhanced, and permeation uniformity and overall permeability are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of anode flow field plates for PEM water electrolyzers, in particular to a composite anode flow field plate for PEM water electrolyzers. Background Art

[0002] As a crucial water electrolysis technology, PEM (proton exchange membrane) electrolyzer has been widely used in many fields such as electric vehicles, energy storage and industrial hydrogen production. Its outstanding features include low operating temperature, fast response speed and high hydrogen production efficiency.

[0003] As the main component of the PEM electrolyzer, the bipolar plate plays a role in electron conduction and mechanical support. More importantly, its flow channel design affects the mass transport of gas-liquid two-phase flow in the porous transport layer, the uniformity of current density distribution, and membrane electrode hydration. These aspects directly affect the performance and service life of the electrolyzer. Therefore, the design of the bipolar plate needs to ensure that factors such as flow uniformity, liquid water permeability, and flow resistance are fully considered.

[0004] At present, the flow channel designs of bipolar plates in PEM electrolyzers mainly include straight flow channels, serpentine flow channels, grid flow channels, etc. Different types of flow channels have their own advantages and disadvantages. Usually, a specific flow channel type is selected for the electrolyzer according to the specific specifications and models. During the gas production process of the PEM electrolyzer, the generated gas continuously converges to the outlet, so that the volume fraction of gas in the reaction area near the outlet is higher than that in other reaction areas, resulting in poorer penetration of raw water in the area near the outlet than in other areas, and a single flow channel type cannot solve this uneven penetration. Summary of the invention

[0005] The purpose of the utility model is to provide a composite flow field plate for the anode of a PEM water electrolyzer, which can adopt different flow channel types in the near-outlet area to enhance the penetration of raw water in this area, improve the penetration uniformity and overall permeability, so as to solve the technical problem that the penetration of raw water in the near-outlet area is poorer than that in other areas proposed in the above-mentioned background technology, and a single flow channel type cannot solve this penetration unevenness.

[0006] Specifically, the composite flow field plate is mainly used in small electrolytic cells using serpentine flow channels. A wavy flow channel is partially used in the downstream area near the outlet to enhance the penetration of raw water in this area and improve the penetration uniformity, thereby improving the overall performance of the electrolytic cell.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] A composite flow field plate for an anode of a PEM water electrolyzer, comprising:

[0009] Flow field inlet;

[0010] A main flow area, connected to the flow field inlet, including a plurality of parallel first flow channels;

[0011] A downstream permeation enhancement zone includes a plurality of parallel second flow channels, wherein the second flow channels are used to enhance local permeation; the second flow channels are connected to the first flow channels, and the second flow channels and the first flow channels are of different flow channel types;

[0012] a flow field outlet, connected to the second flow channel of the downstream permeation enhancement zone;

[0013] The raw material flows in the order of the flow field inlet, the first flow channel, the second flow channel, and the flow field outlet.

[0014] As a preferred implementation, the first flow channel is a serpentine flow channel, and the first flow channel is a serpentine flow channel, extending toward the flow field outlet in a serpentine manner.

[0015] As a preferred implementation, the widths of the first flow channels are the same.

[0016] As a preferred implementation, the number of the first flow channels is determined by the width of the flow field inlet and the flow field outlet.

[0017] As a preferred implementation, the flow field inlet and the flow field outlet are arranged along the diagonal line of the flow field plate.

[0018] As a preferred implementation, the number of U-shapes of the serpentine flow channel is an even number.

[0019] As a preferred embodiment, the second flow channel is a wave-shaped flow channel, which is used to improve the permeability of raw water in this area.

[0020] As a preferred implementation, the wave crest of the second flow channel is connected to the flow field outlet, and the wave trough of the second flow channel is connected to the first flow channel.

[0021] As a preferred embodiment, the downstream permeability enhancement zone further includes a guide ridge.

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] 1. The local use of wave-shaped flow channels strengthens the penetration of raw water near the outlet area, improving the penetration uniformity and overall permeability;

[0024] 2. While using the wavy flow channel to improve local permeability, it will not have a significant impact on the flow resistance of the local area, thereby avoiding large system energy consumption;

[0025] 3. The serpentine flow channel is combined with the local wave-shaped flow channel, which retains the flow uniformity of the serpentine flow channel and improves the problem of uneven penetration of the single-type flow channel. It has high design flexibility and is especially suitable for small PEM water electrolyzers. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a front view of the composite flow field plate of the anode of the PEM water electrolyzer in the embodiment of the utility model.

[0027] Figure 2 It is a schematic diagram of the composite flow field plate of the anode of the PEM water electrolyzer in the embodiment of the utility model.

[0028] Explanation of the reference numerals: 1. flow field inlet; 2. mainstream area; 21. first flow channel; 3. downstream permeation enhancement area; 31. second flow channel; 32. guide ridge; 4. flow field outlet; 5. flow field plate. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] In the description of the present utility model, it should be noted that "wave period number" and "U-shaped number" are not professional terms, but descriptive terms defined according to specific design contents.

[0031] See also Figure 1 , Figure 2 The utility model provides a composite flow field plate 5 for anode of a PEM water electrolyzer, comprising: a flow field inlet 1, a mainstream area 2, a downstream permeation enhancement area 3, and a flow field outlet 4.

[0032] The flow field inlet 1 is used for the inflow of raw materials. The main flow area 2 is connected to the flow field inlet 1 , and the main flow area 2 includes a plurality of parallel first flow channels 21 .

[0033] The downstream permeation enhancement zone 3 includes a plurality of parallel second flow channels 31, and the second flow channels 31 are used to enhance local permeation. The second flow channels 31 are connected to the first flow channels 21, and the flow channel types of the second flow channels 31 and the first flow channels 21 are different. The downstream permeation enhancement zone 3 uses the second flow channels 31 of a different flow channel type from the first flow channels 21 to enhance local permeation.

[0034] The flow field outlet 4 is communicated with the second flow channel 31 of the downstream permeation enhanced zone 3 .

[0035] The raw material flows in the order of the flow field inlet 1 , the first flow channel 21 , the second flow channel 31 , and the flow field outlet 4 .

[0036] Preferably, the first flow channel 21 is a serpentine flow channel, extending in a serpentine manner toward the flow field outlet 4. The first flow channels 21 are parallel to each other. The widths of the first flow channels 21 are the same. The serpentine flow channel includes several parallel flow channels of the same shape and size, extending in a serpentine manner toward the flow field outlet 4, and has good flow uniformity.

[0037] Preferably, the number of the first flow channels 21 can be determined according to the width of the flow field inlet 1 and the flow field outlet 4. The number of the first parallel flow channels 21 can be determined by the design width of the flow field inlet 1 and the flow field outlet 4, which has high design flexibility and can be designed to be 2 to 12 as needed. As the best embodiment, the number of parallel flow channels in this embodiment is 6.

[0038] Preferably, the flow field inlet 1 and the flow field outlet 4 are arranged along the diagonal line of the flow field plate 5, and the number of U-shapes of the serpentine flow channel is an even number to meet the requirements of symmetric design. As the best embodiment, the number of U-shapes of the serpentine flow channel is 2.

[0039] Preferably, the second flow channel 31 is a wave-shaped flow channel, which is used to improve the permeability of the raw water in this area while avoiding a large resistance drop. As the best embodiment, the wave period number in this embodiment is 2.5. When the wave period number increases to a certain extent, the improvement of permeability will no longer be significant.

[0040] Preferably, the crest of the second flow channel 31 is butted against the flow field outlet 4, and the trough of the second flow channel 31 is butted against the first flow channel 21. The wave-shaped flow channel in the downstream permeation enhancement zone 3 is butted against the flow field outlet 4 at the crest, and is butted against the serpentine flow channel in the mainstream zone 2 at the trough, retaining the flow characteristics of the original serpentine flow channel.

[0041] Preferably, the downstream permeability enhancement zone 3 further includes a guide ridge 32. Figure 1 , Attachment Figure 2 As shown, the wave-shaped second flow channels 31 on both sides have uneven gaps with the side walls of the downstream permeation enhancement zone 3. The guide ridges 32 are arranged at the crests and troughs of the second flow channels 31 to supplement the areas with large gaps, achieve structural support, and enhance the local permeation effect of the raw water.

[0042] The implementation principle of this application is: using a serpentine flow channel combined with a local wavy flow channel to retain the uniformity of the serpentine flow channel, while improving the problem of insufficient permeability in the downstream near-exit area, so as to improve the permeability uniformity and overall permeability, thereby helping to improve the uniformity of current density and electrolysis efficiency. On the other hand, while the wavy flow channel improves local permeability, it will not have a significant impact on the flow resistance of the local area, thereby avoiding greater system energy consumption.

[0043] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A composite flow field plate for anode of a PEM water electrolyzer, characterized in that: include: Flow field inlet; A main flow area, connected to the flow field inlet, including a plurality of parallel first flow channels; A downstream permeation enhancement zone includes a plurality of parallel second flow channels, wherein the second flow channels are used to enhance local permeation; the second flow channels are connected to the first flow channels, and the second flow channels and the first flow channels are of different flow channel types; a flow field outlet, connected to the second flow channel of the downstream permeation enhancement zone; The raw material flows in the order of the flow field inlet, the first flow channel, the second flow channel, and the flow field outlet.

2. A composite flow field plate for anode of a PEM water electrolyzer according to claim 1, characterized in that: The first flow channel is a serpentine flow channel, extending toward the flow field outlet in a serpentine manner.

3. A composite flow field plate for anode of a PEM water electrolyzer according to claim 2, characterized in that: The first flow channels have the same width.

4. A composite flow field plate for anode of a PEM water electrolyzer according to claim 2, characterized in that: The number of the first flow channels is determined by the width of the flow field inlet and the flow field outlet.

5. A composite flow field plate for anode of a PEM water electrolyzer according to claim 2, characterized in that: The flow field inlet and the flow field outlet are arranged along the diagonal line of the flow field plate.

6. A composite flow field plate for anode of a PEM water electrolyzer according to claim 5, characterized in that: The number of U-shapes of the serpentine flow channel is an even number.

7. The composite flow field plate for anode of a PEM water electrolyzer according to claim 1, characterized in that: The second flow channel is a wave-shaped flow channel.

8. A composite flow field plate for anode of a PEM water electrolyzer according to claim 7, characterized in that: The wave crest of the second flow channel is connected to the flow field outlet, and the wave trough of the second flow channel is connected to the first flow channel.

9. A composite flow field plate for anode of a PEM water electrolyzer according to claim 7, characterized in that: The downstream permeability enhancement zone also includes a guide ridge.

Images