Patent Application
20080318115
This application claims the priority benefit of Taiwan application serial no. 96122023, filed on Jun. 20, 2007. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
1. Field of the Invention
The present invention relates to a flow channel plate, and more particularly, to a flow channel plate suitable for use in a fuel cell.
2. Description of Related Art
Fuel cell has the advantages of high efficiency, low noise and pollution-free, and is a fuel technology conforming to the trend of the present times. Fuel cells are classified into many types, while the commonly seen fuel cells are PEMFC (proton exchange membrane fuel cell) and DMFC (direct methanol fuel cell).
DMFC uses methanol-water solution as a fuel supply source, and generates current through related electrode reactions of methanol, oxygen and water. The chemical reactions are indicated as follows.
Anode: CH3OH+H2O→CO2+6H++6e−
Cathode: 3/2O2+6H+6e−→3H2O
Overall reaction: CH3OH+H2O+3/2O2→CO2+3H2O
A DMFCDMFC usually has an anode flow channel plate for supplying methanol-water solution. The methanol-water solution entered into the anode flow channel plate reacts with anode catalyst.
Referring to
Since the length of the serpentine flow channel 110 is relatively long, and which leads to a too large pressure drop while the methanol-water solution flows. Therefore, a pump that can produce a higher pressure is needed in order to drive the methanol solution, so it is more energy consuming. In addition, the methanol-water solution of the upstream of the serpentine flow channel 110 flows to the downstream of the serpentine flow channel 110 after reaction. As a consequence, the concentration of the methanol-water solution of the downstream is lower than the concentration of the methanol-water solution of the upstream. In other words, the concentration of the methanol-water solution in the anode flow channel plate 100a is uneven, and this leads to poor reaction efficiency.
Referring to
The present invention provides a flow channel plate to increase the reaction efficiency of fuel cell.
An embodiment of the present invention provides a flow channel plate suitable for use in a fuel cell. The flow channel plate includes a plate body and at least a group of flow guiding blocks. The plate body has a first side wall and a second side wall opposite to the first side wall. The first side wall has at least an inlet; and the second side wall has at least an outlet. The group of flow guiding blocks is disposed in the plate body and is adjacent to the first side wall, and includes a plurality of flow guiding blocks. One of the flow guiding blocks is a first flow guiding block, and the first flow guiding block is aligned with the inlet. The rest of the flow guiding blocks are arranged into m rows between the first flow guiding block and the second side wall and the first row of the m rows is adjacent to the first flow guiding block, and a number Nm of flow guiding blocks of the mth row is plural, where m is a natural number, and Nm+1≧Nm. A geometrical center of the flow guiding blocks at one end of the first row and a geometrical center of the first flow guiding block are on a straight line, and an included angle is formed between the straight line and the first side wall.
The flow channel plate guides the flow of fluid in the flow channel plate through the flow guiding block. When the flow channel plate is used as the anode flow channel plate of fuel cell, the flow guiding blocks can make an even distribution of fuel introduced into the flow channel plate. Thus, fuel can evenly flow to the anode catalyst, so the reaction efficiency is increased.
Other objectives, features and advantages of the present invention will be further understood from the further technological features disclosed by the embodiments of the present invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention.
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” etc., is used with reference to the orientation of the Figure(s) being described. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. On the other hand, the drawings are only schematic and the sizes of components may be exaggerated for clarity. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,”. “coupled,” and “mounted” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. Similarly, the terms “facing,” “faces” and variations thereof herein are used broadly and encompass direct and indirect facing, and “adjacent to” and variations thereof herein are used broadly and encompass directly and indirectly “adjacent to”. Therefore, the description of “A” component facing “B” component herein may contain the situations that “A” component facing “B” component directly or one or more additional components is between “A” component and “B” component. Also, the description of “A” component “adjacent to” “B” component herein may contain the situations that “A” component is directly “adjacent to” “B” component or one or more additional components is between “A” component and “B” component. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.
Referring to
According to the above description, the inlet 212a, for example, is aligned with the outlet 214a, and one of the flow guiding blocks 220 is a first flow guiding block 222, and the first flow guiding block 222 is aligned with the inlet 212a. In other words, the first flow guiding block 222, the inlet 212a and the outlet 214a, for example, are in the same straight line. The dimension of the first flow guiding block 222, for example, is larger than the dimension of the inlet 212a. In addition, the rest of the flow guiding blocks 220 are arranged into m rows between the first flow guiding blocks 222 and the second side wall 214, and the first row of the m rows is adjacent to the first flow guiding block 222. In addition, the number Nm of the flow guiding blocks 220 of mth row is plural, wherein m is a natural number, and Nm+1≧Nm.
In the present embodiment, for example, the number of the flow guiding blocks 220 is five, and the flow guiding blocks 220 other than the first flow guiding block 222 are arranged into two rows, and the number of the flow guiding blocks 220 in each row is two. In addition, a straight line 50 passes through the geometrical center of the flow guiding blocks 220 of one end of the first row and the geometrical center of the first flow guiding block 222, and there is an included angle θ between the straight line 50 and the first side wall 212.
The distance between the flow guiding blocks 220 at the two ends of the mth row is D1m and D1m+1≧D1m. More specifically, the distance D12 between the flow guiding blocks 220 at the two ends of the second row is longer than the distance D11 between the flow guiding blocks 220 at the two ends of the first row. In addition, the flow guiding blocks 220 at the two ends of the mth row are at the two sides of the inlet 212a. In addition, the shortest distance between the first flow guiding block 220 and the first side wall 212 is D2, and the shortest distance between each of the flow guiding blocks of the mth row and the first side wall 212 is D2m, and D2m+1>D2m>D2. More specifically, the shortest distance between each of the flow guiding blocks 220 of the first row and the first side wall 212 is D21, the shortest distance between each of the flow guiding blocks 220 of the second row and the first side wall 212 is D22, and D22>D21>D2.
When the flow channel plate 200 is used as the anode flow channel plate of a fuel cell, fuel flows therein through the inlet 212a. And the solid arrow in
In addition, since the structure of the flow channel plate 200 of the present embodiment is simple and easy to fabricate, therefore the manufacturing cost thereof is relatively low. In addition, since the pressure drop is small when fuel flows in the flow channel plate 200, a pump with smaller power may be used to save energy. Moreover, the flow resistance of the flow channel plate 200 is small, therefore the anode reaction product (for example carbon dioxide) is easier to discharge, and thus an adverse effect on the reaction efficiency can be avoided.
In addition, other than column shape, the shape of the flow guiding block 220 may also be designed in a pear shape as shown in
The flow guiding blocks 220 of the flow channel plate of the present invention may be a plurality of groups, and the number of the inlet 212a and the outlet 214a may be plural. The following descriptions use the flow channel plate with two groups of flow guiding blocks 220, two inlets 212a and two outlets 214a as the example.
Referring to
Since the flow channel plate 200c has a plurality of groups of flow guiding blocks 220, the fuel flow in the plate body 210 is more uniform, so the reaction efficiency is increased.
To sum up, the flow channel plate of the present invention at least has one of the following advantages:
1. When the flow channel plate of the present invention is used as the anode flow channel plate of a fuel cell, the flow guiding blocks can make the distribution of fuel flow to the flow channel plate uniform, so that fuel uniformly flows to the anode catalyst, and further the reaction efficiency is increased.
2. Since the structure of the flow channel plate of the present invention is simple and easy to fabricate, the manufacturing cost is relatively low.
3. Since the pressure drop of fuel flows is small when the fuel flows in the flow channel plate, a pump with a smaller power may be sufficient and the energy consumption may be reduced.
4. Since the flow resistance of the flow channel plate is small, when the flow channel plate is used as the anode flow channel plate of a fuel cell, the anode reaction product (for example carbon dioxide) may be easily removed, and thus an adverse effect on the reaction efficiency can be avoided.
The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like is not necessary limited the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from this disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the invention. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the present invention as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 96122023 | Jun 2007 | TW | national |
