CN113013435B

CN113013435B - Flow channel layout of proton exchange membrane fuel cell taking biological blood vessel as inspiration

Info

Publication number: CN113013435B
Application number: CN201911326670.1A
Authority: CN
Inventors: 黄豪中; 雷涵; 郭晓宇
Original assignee: Guangxi University
Current assignee: Guangxi University
Priority date: 2019-12-20
Filing date: 2019-12-20
Publication date: 2023-08-01
Anticipated expiration: 2039-12-20
Also published as: CN113013435A

Abstract

The utility model adopts the following technical scheme that a novel fuel cell flow field similar to the layout mode of blood vessels and branches distributed on human mesentery is arranged by taking biological blood vessels as inspiration, and comprises a fuel cell flow field main road, main road branches and a net-shaped flow channel structure similar to capillary vessels. The flow channels are sent out from the center of the bipolar plate to the periphery, run right, run left, ascend and descend respectively and are matched with the edge flow channels on four sides. The uniform flow channel water distribution mode is realized, the short-range high-activity area distribution mode is adopted, the purpose is to reduce the pressure drop caused by the long range, alleviate the electrode product blockage caused by too many flow channel turns, and avoid the problems of insufficient air supply and the like.

Description

Flow channel layout of proton exchange membrane fuel cell taking biological blood vessel as inspiration

Technical Field

The utility model belongs to the technical field of fuel cells, and particularly relates to a fuel cell flow field layout taking human mesenteric vessels and branches as inspiration.

Background

Under the premise that world petroleum resources are increasingly scarce and global warming is increasingly promoted, the development of clean energy is increasingly important, the application of hydrogen energy becomes the research focus in the world at present, a fuel cell spans a heat engine process, a Carnot cycle does not exist, chemical energy of fuel and oxidant is directly converted into electric energy, and the energy conversion efficiency is extremely high, so that the fuel cell becomes one of the most promising power sources at present.

In Proton Exchange Membrane Fuel Cells (PEMFC), water is generated in a cathode Catalyst Layer (CL), then transported to the surface of a Membrane Electrode (MEA) through a Gas Diffusion Layer (GDL), and finally flows out of a flow channel. To ensure a Proton Exchange Membrane (PEM) with a high proton conductivity, its high water content must be maintained. However, excessive water in the flow channels of the fuel cell may obstruct an effective path for oxygen diffusion, limit the reaction rate of the Catalyst Layers (CLs), and greatly reduce the performance of the cell, which is called flooding, which causes uneven distribution of reactants in the fuel cell, thereby causing problems such as uneven current density, localized hot spots in the membrane, degradation of performance, and aging of materials. Flow channel flooding is a major factor restricting the performance of the fuel cell, and directly leads to the performance degradation of the fuel cell, so that the water management on the cathode side of the fuel cell is crucial for improving the performance of the fuel cell, and the water management and the transport capacity of reactants to the porous gas diffusion layer and the catalytic layer are required to be promoted by improving the actions such as flow channel structures.

Disclosure of Invention

The utility model provides a flow channel layout of a proton exchange membrane fuel cell taking biological blood vessels as inspiration, which reduces the pressure drop caused by long-distance travel, slows down the electrode product blockage caused by too many turns of the flow channel, and avoids the problems of insufficient air supply and the like.

The utility model adopts the following technical proposal

A fuel cell runner taking blood vessel and branch on human mesentery as inspiration comprises a main runner of a flow field, branches of the main runner and net-shaped branches similar to capillary vessels in layout.

The fuel cell is similar to the distribution of multiple branches of arterial blood vessel, so that the flow channel is distributed in a way that the center diverges to the periphery, the length of the flow channel is reduced, and the transportation distance of reaction products and reactants in the flow channel is shortened.

Eight flow field main channels are uniformly and symmetrically distributed, and four net-shaped flow channels similar to capillary vessels are symmetrically distributed on four sides of the flow channels.

The flow field of the fuel cell is similar to the reticular branches of capillary vessels, so that the active area of the fuel cell is enlarged, and the contact area of the flow channel and the gas diffusion layer is enlarged.

The flow channel inlet is arranged at the center of the bipolar plate, and the flow channel outlets are arranged at the four corners of the flow field, so that the length of the flow channel along the path is shortened.

And introducing air into the center of the novel flow field taking the upper blood vessel and branches of the human mesentery as inspiration, and discharging liquid water which is a reaction product from four corners of the flow field.

The groove depth of the whole flow field is 1mm.

The novel cathode runner of the fuel cell taking the arterial blood vessel and the branches on the biological mesentery as the design inspiration is characterized in that the novel runner layout combines a runner structure with a slope, the runner forms of trapezoid cross-section structures are selected on four sides, different air inlet and outlet modes achieve the short-path layout of the runner, a net runner structure similar to the distribution of capillary blood vessels achieves the distribution mode with high active area, and the novel cathode runner is aimed at reducing the pressure drop caused by long-path, slowing down the electrode product blockage caused by too much turning of the runner, and avoiding the problems of insufficient air supply and the like.

Drawings

FIG. one is an elevation view of a novel flow field layout taking a blood vessel on a human mesentery and branches thereof as inspiration;

wherein: 1. flow channel inlet 2, flow channel outlet 3, flow channel outlet 4, flow channel outlet 5, flow channel outlet 6, net-shaped flow channel layout 7, flow field main channel (inclined) 8, flow field main channel (vertical) 9, flow field main channel (straight) 10, bipolar plate

Description of the embodiments

The flow channel design of the present utility model will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that terms such as "left", "right", "upper", "lower", and the like appear,

"flat", "inclined", "vertical", etc., which indicate an azimuth or a positional relationship based on that shown in the drawings, are merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a specific azimuth, be constructed and operated in a specific azimuth, and thus should not be construed as limiting the utility model. Furthermore, the terms "first," "second," "third," and the like, as used herein, are used for descriptive purposes only. And are not to be construed as indicating or implying relative importance.

In this embodiment, the bipolar plate material is a graphite plate with good electrical conductivity, thermal conductivity and corrosion resistance, further, the bipolar plate further comprises fixing bolts, and four corners of the bipolar plate are respectively provided with first, second, third and fourth positioning holes matched with the fixing bolts, so that the cathode plate and the anode plate can be connected with each other, the connection is more stable, and the fuel cell stack formed by combining a plurality of monomers is also more stable.

As shown in figure 1, the novel flow channels are arranged on the bipolar plate in a novel flow channel layout similar to biological blood vessel distribution, flow channel inlets are arranged at the center of the bipolar plate, eight main channels equally divide flow field areas, a plurality of flow channels are evenly branched from the upper part and the lower part of the inclined and straight main channels and from the left and the right parts of the numerical main channels, the flow channels at the periphery of the flow fields are similar to a human capillary vessel net flow field structure, flow field four corners are flow channel outlets, and liquid water which is a reaction product is discharged.

The flow field structure with biological blood vessel as inspiration is distributed symmetrically.

In this embodiment, the air flow enters through the flow channel inlet 1. Through the branches, liquid water and air are discharged from the flow channel outlets 2, 3, 4, 5.

On the basis of the embodiment, the novel branch cross-sectional areas are the same.

The novel runner is engraved by a precise numerical control milling machine or a engraving and milling machine strictly according to the design size.

In this embodiment, the depth of the flow field groove formed by the novel flow channel is lmm.

The flow passage cross section may have a square cross section of 1mmX1mm in shape in the vertical and extending directions.

The flow channels on the bipolar plates are all smooth, the contact angle between the liquid water and the wall surfaces of the flow channels is increased, namely, the flow channels are hydrophobic, and the liquid water can be discharged out of the flow channels as soon as possible.

The above is only for illustrating the technical idea of the present utility model, and the scope of the present utility model is not limited thereto, and any modification made on the basis of the technical scheme according to the technical idea of the present utility model falls within the scope of the claims of the present utility model.

Claims

1. The novel cathode runner layout of the proton exchange membrane fuel cell similar to the blood vessel and branch on the biological mesentery is characterized in that: based on the conventional serpentine runner structure construction standard, a layout mode similar to the distribution of arterial blood vessels in a human body is arranged, a runner inlet is arranged at the center of a bipolar plate, the runner is sent out to the periphery at the center of the bipolar plate, and goes right, left and right, branches are lifted and are matched with edge runners with sloping surfaces on four sides, eight main runners form an octagonal runner inlet at the right center of the bipolar plate, eight branches uniformly divide eight areas, each main runner uniformly divides a plurality of branches similar to arterial blood vessels, a reticular runner structure similar to capillary vessels is arranged near each four sides, runner outlets are arranged at four opposite corners of a square flow field, a uniform runner water distribution mode is realized, the runner inlet end is an air flow inlet, and the outlet end is a liquid water outlet, namely the air flow blows redundant liquid water out of the runner to avoid the occurrence of flooding phenomenon.

2. The novel cathode runner layout of the proton exchange membrane fuel cell according to claim 1, wherein the runners are distributed as square flow fields on the bipolar plate.

3. The novel cathode runner layout of proton exchange membrane fuel cell as claimed in claim 1, wherein each branch of the runner taking biological blood vessel as inspiration is uniformly symmetrical.

4. The pem fuel cell novel cathode flow-channel layout of claim 1 wherein the novel flow-channel composed flow-field region is located intermediate the bipolar plate and gas diffusion layer of the fuel cell assembly.

5. The novel cathode runner layout of the proton exchange membrane fuel cell according to claim 1, wherein the novel runner layout combines a runner structure with a slope, a runner form with a trapezoid cross-section structure is selected on four sides, different air inlet and outlet modes achieve a short-path layout of the runner, a net runner structure similar to capillary distribution achieves a distribution mode with a full high active area, and the novel cathode runner layout aims at reducing pressure drop caused by long-path, slowing down electrode product blockage caused by too many turnings of the runner, and avoiding the problem of insufficient air supply.