WO2009008534A1

WO2009008534A1 - Separator for fuel cell

Info

Publication number: WO2009008534A1
Application number: PCT/JP2008/062661
Authority: WO
Inventors: Keiji Hashimoto; Kazunari Moteki
Original assignee: Toyota Shatai Kabushiki Kaisha; Toyota Jidosha Kabushiki Kaisha
Priority date: 2007-07-10
Filing date: 2008-07-08
Publication date: 2009-01-15
Also published as: JP4924829B2; JP2009021022A

Abstract

A separator (10) has a separator body (11) and a collector (12). The body (11) prevents fuel gas and oxidant gas from flowing in a mixed state. The collector (12) has first projection/recess forming sections (12a), in each of which projection/recess sections having a substantially rectangular cross-section are continuously formed, and also has a second projection/recess forming section (12b), in each of which recess sections having a substantially rectangular cross-section are formed with a cycle shifted by half a cycle from the cycle of the projection/recess sections of the first projection/recess forming sections (12a). The collector (12) has flat plate sections (12c) for forming flow paths causing introduced gas to meander from the forming sections (12a) toward the forming sections (12b). The construction enables the introduced gas to be diffused in a good manner and generated water to be discharged in a good manner.

Description

Specification

Fuel Cell Separator Technology Field

The present invention relates to a fuel cell separator, and more particularly to a fuel cell separator employed in a polymer electrolyte fuel cell. Background art.

In general, a polymer electrolyte fuel cell includes an electrode structure including an anode electrode layer formed on one side of an electrolyte membrane and a force sword electrode layer formed on the other side. In the polymer electrolyte fuel cell, a fuel gas (for example, hydrogen gas) and an oxidant gas (for example, air) are supplied from the outside to the anode electrode layer and the force sword electrode layer, respectively. As a result, an electrode reaction occurs in the electrode structure to generate power. For this reason, in order to improve the power generation efficiency of the polymer electrolyte fuel cell, it is important to efficiently supply the fuel gas and oxidant gas necessary for the electrode reaction to the electrode structure.

Here, in the polymer electrolyte fuel cell, a separator for supplying the fuel gas and the oxidant gas supplied from the outside separately to the anode electrode layer and the force sword electrode layer is provided. . Conventionally, the power generation efficiency of a polymer electrolyte fuel cell has been improved by improving the supply efficiency of fuel gas and oxidant gas by a separator.

For example, Japanese Laid-Open Patent Publication No. 2 005-2 0 9 4 70 discloses a fuel cell that uses a separator composed of a thin flat plate-like substrate and a mesh-like conductor. The mesh-like conductor in this conventional fuel cell is made of, for example, expanded metal or metallases having diamond-shaped slits. The mesh-like conductor is formed with a plurality of gas flow paths in which a cross-sectional shape perpendicular to the flow direction of the fuel gas or air (oxidant gas) introduced from the outside is formed into a substantially rectangular shape. Yes. As a result, the fuel gas or the oxidant gas introduced from the outside flows through the gas flow passage formed in the shape of a paddle, and is supplied to the anode electrode layer or the force sword electrode layer through the diamond-shaped slit. The Thus, by supplying the fuel gas or the oxidant gas, the gas supply and soot efficiency is improved. Also, for example, Japanese Patent Laid-Open No. 2002-184422 discloses a fuel cell separator that can improve the gas supply efficiency of the separator. The fuel cell separator has a flat plate-shaped first member (carbon), and is laminated on the first member to elastically contact the anode electrode layer and the force sword electrode layer and to form a gas flow path. And a second member (metal plate) on which a plurality of protrusions are formed. In this conventional fuel cell separator, the fuel gas and the oxidant gas passing therethrough are caused to flow by passing through the gas flow path formed by the plurality of protrusions of the second member. It is like that. As a result, the fuel gas and the oxidant gas supplied into the gas flow path can be diffused well by three-dimensionally passing in all directions, and the gas supply efficiency to the anode electrode layer and the force sword electrode layer is improved. It has come to improve. Disclosure of invention

By the way, in the mesh-like conductor shown in the above-mentioned JP-A-2005-209470 and the second member shown in the above-mentioned JP-A-2002-184422, the gas flow having a substantially rectangular cross section is formed. For example, the gas flow path formed by the projecting piece is substantially parallel to the direction connecting the introduction port for introducing the fuel gas and the oxidant gas into the inside and the outlet port for introducing the introduced gas to the outside. There is ^. For this reason, the inlet and outlet can communicate linearly with the formed gas flow path. As a result, part of the introduced fuel gas and oxidant gas is diffused by the mesh protrusions formed on the conductor and consumed by the anode electrode layer and the cathode electrode layer, but the other part is In other words, there is a possibility of being discharged outside without being consumed without being spread. In this way, in the situation where fuel gas and oxidant gas discharged without being consumed, that is, unreacted gas, increase in power generation efficiency in the fuel cell cannot be expected. ,

In a polymer electrolyte fuel cell, when an electrode reaction using a fuel gas and an oxidant gas proceeds in the electrode structure, water is generated in the anode electrode layer or the force sword electrode layer according to the ion exchange characteristics of the electrolyte membrane. Produces. The generated water (produced water) covers, for example, the surface of the anode electrode layer or the force sword electrode layer, the mesh of conductors disclosed in the above-mentioned JP-A-2005-209470, and the above-mentioned JP-A Good supply of fuel gas or oxidant gas is impaired by adhering to the projecting piece of the second member disclosed in the 2002-184422 publication. There is a possibility. Therefore, the power generation efficiency in the fuel cell may decrease as the electrode reaction progresses. In addition, when the polymer electrolyte fuel cell is installed in an environment having a low temperature atmosphere, for example, the generated water remaining inside freezes, so that the fuel gas or the oxidizing agent gas is not sufficiently supplied. As a result, the low temperature startability of the fuel cell may deteriorate. For this reason, the water produced by the electrode reaction must be efficiently discharged to the outside. The present invention has been made in order to solve the above-described problems, and its purpose is to provide a good supply performance of fuel gas and oxidant gas and a good drainage performance of generated water generated by electrode reaction. The object is to provide a fuel cell separator that is compatible.

In order to achieve the above object, a feature of the present invention is that a fuel cell separator that supplies an externally introduced fuel gas and an oxidant gas to an electrode layer that constitutes an electrode structure of a fuel cell. In which the fuel gas and the oxidant gas are separated to prevent mixed flow, and the fuel gas or the oxidant gas separated by the separator body is dispersed to disperse the electrode structure. A collector that collects electricity generated by an electrode reaction in the electrode structure, the gap for allowing the separated fuel gas or oxidant gas to flow three-dimensionally A plurality of concave portions and convex portions formed between the separator main body and the electrode structure are linearly and continuously molded; and a concave portion and a concave portion of the first concave / convex molded portion. A gap is formed between the separator body and the electrode structure so that the separated fuel gas or oxidant gas flows three-dimensionally with respect to the molding period of the convex portion. A plurality of concave portions and convex portions that are formed linearly and continuously, and formed between the first concave-convex molded portion and the second concave-convex molded portion. The concavo-convex molded portion and the second concavo-convex molded portion are connected to each other, and the second concavo-convex molded portion is formed from a gap formed by the recessed portion of the first concavo-convex molded portion of the separated fuel gas or oxidant gas. The flow path to the gap formed by the concave portion of the first concave and convex portion and the flow path to the gap formed by the convex portion of the second concave and convex molded portion from the gap formed by the flange portion of the first concave and convex molded portion are formed. And a collector with a flow path forming section There is.

According to this, the separator body that separates the fuel gas and the oxidant gas introduced from the outside to prevent mixed flow, and the separated fuel gas and the oxidant gas are diffused and supplied to the electrode structure. A fuel cell separator can be constituted by a collector for collecting current. The collector forms a gap for three-dimensional distribution of fuel gas or oxidant gas. In order to achieve this, the first concave-convex molded portion and the second concave-convex molded portion have different molding periods of the plurality of concave portions and convex portions by a half cycle. The fuel gas or the oxidant gas that has passed through the formed gap may have a flow path forming portion that forms a flow path that flows toward the gap formed by the uneven portion of the second uneven formed portion. Here, the flow path forming part is formed by the recessed part of the second concavo-convex forming part from the gap formed by the recessed part of the first concave ridge forming part in which the separated fuel gas or oxidant gas differs by a half cycle. A flow path that circulates in the formed gap, and a flow path that circulates from the gap formed by the convex portion of the first concavo-convex molded portion to the gap formed by the convex portion of the second concavo-convex molded portion. it can.

In this way, the flow path forming portion forms the flow path of the fuel gas or the oxidant gas, so that the concave portion (convex portion) is opposed to the gap formed by the concave portion (convex portion) of the first concave-convex forming portion. The flow of fuel gas or oxidant gas toward the gap formed by the convex part (concave part) of the second concave-convex molded part can be hindered. That is, the fuel gas or the oxidant gas is linearly directed from the gap formed by the concave portion (convex portion) of the first concave-convex forming portion toward the gap formed by the convex portion (concave portion) of the second concave-convex forming portion. Without passing through, it snakes and circulates toward the gap formed by the concave portion (convex portion) formed adjacent to the convex portion (concave portion) in the second concavo-convex molded portion. As a result, the fuel gas or the oxidant gas is well diffused by meandering from the first concavo-convex molded portion to the second concavo-convex formed portion, and is sufficiently diffused to the electrode layer constituting the electrode structure. Fuel gas or oxidant gas can be supplied. Therefore, good gas supply performance can be ensured, and the amount of unreacted fuel gas or oxidant gas that is not consumed by the electrode structure can be reduced.

Further, the fuel gas or the oxidant gas separated by the separator main body has a gap formed by the concave or convex portion of the first concavo-convex molded portion and a gap formed by the concave or convex portion of the second concavo-convex molded portion. It passes through across and is supplied to the electrode layer constituting the electrode structure. For this reason, for example, when the generated water generated near the collector due to the action of surface tension, the generated water can be discharged together with the unreacted gas on the flow of fuel gas or oxidant gas. As a result, as long as the fuel gas and the oxidant gas are supplied, in other words, as long as the solid polymer β-ion battery is used, the generated water can be drained continuously. Therefore, it is possible to ensure good drainage performance of generated water.

In this case, the arrangement direction of the first concavo-convex molded portion and the second concavo-convex molded portion is the separator. It is said that it is substantially parallel to the flow direction of the fuel gas or oxidant gas separated by the generator body. .

According to this, the introduced fuel gas or oxidant gas inevitably has a gap formed by the concave and convex portions of the first concavo-convex molded portion and the concave and convex portions of the second concavo-convex molded portion. It is possible to circulate so as to cross the gap formed. As a result, fuel gas or oxidant gas circulates through the collector, which is inevitably diffused to ensure good gas supply performance, and inevitably secure good drainage performance of the generated water as the gas is discharged. it can.

In addition, the shape in the forming direction of the concave and convex portions that respectively form the first concavo-convex molded portion and the second concavo-convex molded portion may be each rectangular shape. According to this, the first concavo-convex molded part and the second concavo-convex molded part can be formed very easily without any special processing. Therefore, the manufacturing cost of the fuel cell separator can be reduced.

Furthermore, it is preferable that the collector has a plurality of the first concavo-convex forming part, the flow path forming part, and the second concavo-convex forming part sequentially and continuously formed. According to this, the number of times that the fuel gas or the oxidizing agent gas passes through the gap formed by the second concavo-convex molded portion from the gap formed by the first concavo-convex molded portion, that is, the number of times of meandering Can do. In addition, since there is a portion where the first concavo-convex molded portion and the second concavo-convex molded portion are arranged adjacent to each other, the separated fuel gas or oxidant gas is passed between the separator body and the electrode structure. It can also be distributed in three dimensions. For this reason, fuel gas or oxidant gas can be diffused better, and good gas supply performance can be ensured. Furthermore, by forming a plurality of first concavo-convex molded portions and second concavo-convex molded portions, the generated water generated by the electrode reaction in the electrode structure more easily reaches the vicinity of the collector. The drainage performance can be ensured.

Another feature of the present invention is that the flow path forming part includes a flat surface including a bottom part of a concave part forming the first concave-convex molded part and a bottom part of a concave part forming the second concave-convex molded part, and the first It may be formed between the top of the convex part forming the concave-convex molded part and a plane including the top part of the convex part forming the second concave-convex molded part.

In this case, the flow path forming portion includes a concave portion that forms the first concave-convex molded portion and a molding direction of the concave portion that forms the second concave-convex molded portion, and a convex portion that forms the first concave-convex molded portion, and A flat plate including at least a neutral surface with respect to the molding direction of the convex portions forming the second rib molding portion It may be formed into a shape. In addition, the bottom of the concave portion forming the second concave-convex forming portion and the bottom portion of the concave portion forming the first molding portion with respect to the flow path forming portion molded into the flat plate shape are shown in this figure. So as to protrude by the thickness of the plate at the bottom, and so that the top of the projection forming the first concavo-convex molding portion and the top of the projection forming the second concavo-convex molding portion protrude by the thickness of the plate at the top. Well then,

According to these, a flat surface including the bottoms of the concave portions forming the first concavo-convex molded portion and the second concavo-convex molded portion, and a flat surface including the tops of the convex portions forming the first concavo-convex molded portion and the second concavo-convex molded portion In the meantime, a plate-shaped flow path forming part can be formed. More specifically, the plate-shaped flow path forming part is formed with the forming direction of the recesses forming the first uneven forming part and the second uneven forming part, and the first uneven forming part and the second uneven forming part. Neutral surface with respect to the molding direction of the convex part, that is, the bottom part of the concave part forming the first concave and convex part and the second convex part and the top part of the flange part forming the first concave and convex part It can shape | mold so that the neutral surface in the approximate middle may be included. As a result, the flow path of the fuel gas or the oxidant gas from the first concavo-convex molded portion to the second concavo-convex molded portion formed by the concave portion or the convex portion is formed as a flat plate-like flow passage in the molding direction of the concave portion and the convex portion. Divided by the part (approximately equal when the flow path forming part includes a neutral surface). For this reason, for example, when the fuel gas or the oxidant gas flows from the gap formed by the concave portion of the first concavo-convex molded portion toward the gap formed by the opposing second concavo-convex molded portion, The distance between the bottom of the recess in the molding part and the flow path forming part is narrowed, and the fuel gas or the oxidant gas is less likely to flow. Similarly, for example, if a fuel gas or an oxidant gas flows from the convex portion of the first concave-convex molded portion to the opposing second concave-convex molded portion, it flows with the top of the convex portion in the first concave-convex molded portion. The space between the passage forming portion is narrowed and fuel gas or oxidant gas is less likely to flow.

As a result, the part where the fuel gas or the oxidant gas is more likely to flow, specifically, the lower part of the convex part or the upper part of the concave part in the first concave-convex molding part among the gaps divided by the flow path forming part. Will be distributed preferentially. Similarly, in the second concavo-convex molded portion, the fuel gas or the oxidant gas is more easily circulated, specifically, in the gaps divided by the flow path forming portion, The upper part of the recess is preferentially distributed. As a result, the fuel gas or the oxidant gas is formed by the flow path forming part by the upper part of the gap formed by the concave part of the first concave / convex molding part and the concave part of the second concave / convex molding part which are different from each other by a half cycle. Formed Between the upper side of the gap or the lower side of the gap formed by the convex part of the first concave / convex molding part and the lower side of the gap formed by the convex part of the second concave / convex molding part can do . Therefore, the fuel gas or the oxidant gas can be more meandered, the gas supply performance can be improved, and the good drainage performance of the generated water can be secured.

In addition, the bottom of the concave portion of the first concave / convex molding portion and the concave portion of the second concave / convex molding portion is projected by the plate thickness with respect to the flat plate-shaped flow path forming portion, and the convex portion of the first concave / convex molding portion and the second concave / convex portion The top part of the convex part of the molded part can be projected by the thickness. As a result, for example, the fuel gas or the oxidant gas that has flowed through the lower side of the gap formed by the convex portion in the first concave / convex molding portion reaches the concave portion in the second concave / convex molding portion that is molded at a position facing it. At the same time, fuel gas or oxidant gas collides with the bottom side surface of the recess. That is, it is effective that the fuel gas or the oxidant gas flowing through the lower side of the gap formed by the convex portion in the first concave-convex molded portion passes linearly through the concave portion in the second four convex molded portion facing each other. Can be prohibited. Therefore, in this: t, the fuel gas or the oxidant gas can be more meandered, the gas supply efficiency can be improved, and the good drainage of the generated water can be secured. The flow path forming part includes a bottom part of the concave part and the top part of the convex part forming the first concave and convex part, and a top part of the convex part that forms the second concave and convex part and faces the concave part of the first concave and convex part. And it is good to shape | mold into the three-dimensional curved surface which connects the bottom part of the recessed part facing the convex part of the said 1st uneven | corrugated shaped part. '

According to this, the flow path forming part formed into a three-dimensional curved surface connects the top part of the convex part of the second concave-convex molding part formed at a position facing the bottom part of the concave part in the first ridge convex molding part. The bottom of the concave portion of the second concave-convex molded portion formed at a position facing the top of the convex portion of the first concave-convex molded portion can be coupled. Accordingly, the flow of the fuel gas or the oxidant gas from the gap formed by the concave portion in the first concave-convex molded portion to the gap formed by the convex portion in the second concave-convex molded portion, and the convex in the first concave-convex molded portion. It is possible to reliably inhibit the flow of fuel gas or oxidant gas from the gap formed by the portion to the gap formed by the recess in the second concavo-convex molded portion.

In other words, by the flow path forming part formed on the three-dimensional curved surface, the fuel gas or the gas from the gap formed by the concave part of the first concave / convex molding part to the gap formed by the concave part of the second concave / convex molding part Indicates the flow of oxidant gas and the flow of fuel gas or oxidant gas from the gap formed by the convex part of the first concave / convex molding part to the gap formed by the convex part of the second concave / convex molding part. It can be reliably formed. As a result, the fuel gas or the oxidant gas is formed by the flow path forming portion between the concave portion of the first concave-convex molding portion and the concave portion of the second concave-convex molding portion, which differ from each other by a half cycle, or The gap formed by the convex part of the first concave and convex molding part and the convex part of the second concave and convex molding part can meander and circulate. Therefore, the fuel gas or the oxidant gas can be meandered more reliably, the gas supply performance can be improved, and the good drainage performance of the generated water can be secured. A simple explanation of the drawing

FIG. 1 is a schematic view showing a part of a fuel cell stack configured by adopting a fuel cell separator according to the first and second embodiments of the present invention.

FIG. 2 is a schematic perspective view showing a separator main body constituting the separator of FIG. FIG. 3 is a schematic diagram for explaining the collector of FIG.

FIG. 4 is a schematic diagram for explaining the molding cycle of the concave and convex portions of the first concave and convex portion and the second concave and convex portion in the collector of FIG. 3, and (a) is a diagram of the collector of FIG. (B) shows the molding cycle of the concave and convex portions of the second concave-convex molding portion with respect to the first concave-convex molding portion of (a). .

FIG. 5 is a schematic diagram for explaining the flat plate portion in the collector of FIG. 3. (a) shows a cross section in the longitudinal direction of the collector, and (b) shows a cross section in the width direction of the collector. Is.

FIG. 6 is a schematic exploded perspective view for explaining the assembled state of the frame and ME A shown in FIG.

FIG. 7 is a schematic diagram for explaining three-dimensional meandering of fuel gas or oxidant gas by the collector of FIG.

FIG. 8 is a schematic diagram for explaining a collector according to a second embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the three-dimensional curved surface in the collector of FIG.

) Shows a cross section in the longitudinal direction of the collector, and (b) shows a cross section in the width direction of the collector. FIG. 10 is a schematic diagram for explaining three-dimensional meandering of fuel gas or oxidant gas by the collector of FIG. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows a part of a polymer electrolyte fuel cell stack configured by using a fuel cell separator 10 (hereinafter simply referred to as a separator 10) according to a first embodiment of the present invention. FIG. The fuel cell stack is a single unit composed of two separators 10 and a frame 20 and ME A 30 (Membrane-Electrode Assembly) that are stacked between the separators 10. A plurality of cells are stacked.

For example, when a fuel gas such as hydrogen gas and an oxidant gas such as air are introduced into each single cell from the outside of the fuel cell stack, an electrode reaction occurs in ME A 30. Power is generated. Here, in the present specification, in the following description, the fuel gas and the oxidant gas are collectively referred to simply as gas.

As shown in FIG. 1, the separator 10 includes a separator body 11 that prevents mixed flow of gas introduced into the fuel cell stack, and an externally supplied fuel gas or oxidant gas to the ME A 30. It consists of a collector 12 and a collector that collect the electricity generated by the reaction while spreading uniformly.

The separator body 11 is made of a thin metal plate (for example, a stainless steel plate having a thickness of about 0.1 mm) as a material. In addition, as a material for forming the separator body 11, for example, a steel plate subjected to anticorrosion treatment such as gold plating can be employed. In addition, instead of forming the separator body 11 from a thin metal plate, it is also possible to use a non-metallic material having conductivity (for example, carbon) as a raw material.

As shown in FIG. 2, the separator body 11 is formed in a substantially square flat plate shape, and a gas introduction port 1 1a and a gas introduction port 1 1a are opposed to the peripheral portion thereof. Two pairs of gas outlets 1 1 b are formed. Each pair is formed so as to be substantially orthogonal to each other.

The gas inlet 1 1 _a is formed as a substantially oblong through hole, and introduces fuel gas or oxidant gas supplied from the outside of the fuel cell stack into the single cell and is laminated. In addition, fuel gas or oxidant gas supplied to another single cell is circulated. The gas outlet port 1 1 b is also formed as an elliptical through-hole, and out of the gas introduced into the single cell, ME A 3 0 discharges unreacted gas to the outside, and is stacked. Unreacted gas from other single cells is circulated.

The collector 12 is made of a flat material (for example, a stainless steel plate having a thickness of about 0.1 mm). Then, as schematically shown in FIG. 3, the collector 12 is formed by continuously cutting a part of the material so that a concave portion and a convex portion having a substantially rectangular cross section are continuously formed in the plate width direction of the material. The plate width direction of the material by the molding cycle that differs by a half cycle with respect to the molding cycle of the first concave and convex molding portion 12a and the concave and convex molding portions of the first concave and convex molding portion 12a. And a second concavo-convex molded portion 12 b in which a concave portion and a convex portion having a substantially rectangular cross section are continuously formed. More specifically, for example, as shown in FIG. 4 (a), the concave and convex portions in the first concave-convex molded portion 12 a become concave, convex, concave, convex from the left side of the figure. In the case of molding at a molding cycle, the concave and convex portions in the second concave and convex molded portion 1 2 b become convex portions, concave portions, convex portions, concave portions from the left side of the drawing as shown in FIG. 4 (b). Molded with a molding cycle.

Further, the collector 12 connects the first concavo-convex formed portion 12 a and the second concavo-convex formed portion 1 2 b formed with a predetermined interval in the longitudinal direction of the material to each other, and the first concavo-convex portion The flat plate portion 1 2 c has a flat plate portion 1 2 c as a flow path forming portion that forms a gas flow path from the molded portion 1 2 a to the second concave convex molded portion 1 2 b. a), the distance between the virtual plane including the bottom of the concave portion and the virtual plane including the top of the convex portion in the first concave-convex molded portion 12a and the second concave-convex molded portion 12b (i.e., molding) It is molded to include a surface (neutral surface) located approximately in the middle of the height dimension. Then, as shown in FIG. 5 (b), the tops of the convex portions in the first concavo-convex molded portion 1 2 a and the second concavo-convex molded portion 1 2 b are, for example, as thick as the plate thickness It is only protruding. On the other hand, the bottoms of the recesses in the first concavo-convex molded part 12 a and the second concavo-convex molded part 12 b protrude from the lower surface of the flat plate part 12 c by the thickness of the plate, for example. Note that the material characteristics of the material are the same as the molding height of the first uneven part 1 2 a and the second uneven part 1 2 b.

In order to maintain good processability due to (for example, flow characteristics), for example, it may be formed to a molding height of about 3 times or less with respect to the thickness of the material.

And the collector 12 is composed of a first concavo-convex molded part 1 2 a, a flat plate part 1 2 c and The second concavo-convex formed portion 1 2 b is formed by sequentially forming in the longitudinal direction of the material in order.

The collector 12 configured in this way is integrally fixed to the separator body 11 to form the separator 10. The fixing of the collector 12 will be briefly described below. The collector 12 is disposed at a substantially central portion of the separator body 11. Then, the contact portion between the separator body 11 and the collector 12 is metallically joined and fixed integrally by, for example, a brazing method.

More specifically, first, a paste-like brazing material such as copper or nickel is thinly applied to one side of the collector 12. Then, the collector 12 coated with the brazing material is temporarily fixed at a predetermined position of the separator body 11. At this time, the collector 12 includes the arrangement direction of the pair of gas inlets 1 1 a and gas outlets 1 1 b formed in the separator main body 1 1, and the first concavo-convex molded portion 1 2 a and the first 2Temporarily fixed so that it is aligned with the arrangement direction of the concavo-convex molded part 1 2 b. Next, in the reducing gas atmosphere, the temporarily fixed separator body 11 and the collector 12 are heated at a predetermined temperature for a predetermined time, and then cooled. As a result, the separator main body 11 and the collector 12 are joined metallically and fixed integrally.

Here, the joining method for metallically joining the separator body 11 and the collector 12 is not limited to the brazing method described above. That is, other methods that can metallically join the separator body 11 and the collector 12, such as a welding method or a diffusion bonding method, can be employed.

As shown in FIG. 6, the frame 20 is composed of a pair of two resin plate bodies 2 1 and 2 2 having the same structure, and includes two separators 10 (more specifically, the separator body 1 1) Each side is fixed to 1). The resin plate main bodies 2 1 and 2 2 have substantially the same external dimensions as the separator main body 11 1 and a thickness slightly smaller than the molding height of the collector 12. Then, the resin plate main body 2 2 is rotated and arranged approximately 90 degrees in the same plane direction with respect to the resin plate main body 21 and laminated. Various resin materials can be used for the resin plate main bodies 2 1 and 2 2, and it is preferable to use glass epoxy resin. Also, the resin plate main bodies 2 1 and 2 2 have a peripheral portion. The gas inlet port 1 1 a and gas outlet port 1 1 b formed in the separator body 11 in a state where a single cell is formed correspond to the through holes in the separator body 11. Through-holes 21 a, 21 b and through-holes 22 a, having substantially the same shape as the respective through-holes

22b is formed. The resin plate main bodies 21 and 22 are formed with accommodating holes 21 c 22 c for accommodating the collectors 12 joined to the separator main body 11 at substantially central portions thereof. The accommodating holes 21 c and 22 c are formed by a pair of gas inlet 11 a and gas outlet 11 b formed in the separator body 11 to be fixed, and the other resin board body 21 or resin board body 22 stacked. The through-holes 21a and 21b or the through-holes 22a and 22b formed in the inner wall are accommodated.

Thus, by forming the receiving holes 21 c and 22 c, the lower surface (or upper surface) of the separator body 11 to be fixed, the inner peripheral surface of the receiving hole 21 c (or the receiving hole 22 c), and the ME A

A space (hereinafter referred to as a gas conduction space) is formed by the upper surface (or lower surface) of 30. Then, for example, fuel gas can be introduced into the gas conduction space from one gas introduction port 11a, and oxidant gas can be introduced from the other gas introduction port 11a and through-hole 21a force. . In addition, unreacted gas that has passed through the gas conduction space can be led out to the outside through one gas outlet 11 b and through the other gas outlet 11 b and through hole 21 b. it can.

ME A 30 as an electrode structure is formed by laminating an electrolyte membrane EF and a predetermined catalyst on the electrolyte membrane EF in layers as shown in FIGS. 1 and 6, and fuel gas is introduced. The main components are an anode electrode layer AE arranged in the gas conduction space and a force sword electrode layer CE arranged in the gas conduction space into which the oxidant gas is introduced. Note that the actions (electrode reactions) of these electrolytes moon EF, anode electrode layer AE, and force sword electrode layer CE are well known and not directly related to the present invention. Is omitted.

The electrolyte membrane EF may be an ion exchange membrane that selectively permeates cations (more specifically, hydrogen ions (H +)) (for example, Nafion (registered trademark) manufactured by DuPont), or anion (from Specifically, an ion exchange membrane (for example, Tokama Neoceptor (registered trademark)) that selectively transmits hydroxide ions (OH) is formed. The electrolyte membrane EF is larger than the substantially square opening formed when the resin board main bodies 21 and 22 of the frame 20 are laminated, and the resin film main bodies 21 and 22 are laminated. The through holes 21 a and 21 b and the through holes 22 a and 22 b are formed in a size that does not block the through holes. Thus, the electrolyte By forming the membrane EF, it is possible to prevent the gas introduced into the gas conduction space from leaking into the gas conduction space formed on the other side (so-called cross leak).

The anode electrode layer AE and the cathode electrode layer CE as electrode layers are mainly composed of carbon (supported carbon) supporting a noble metal catalyst (for example, platinum (Pt)) or a hydrogen storage alloy. The electroangular membrane is formed in layers on the surface of EF. The anode electrode layer AE and the cathode electrode layer CE formed in layers are slightly smaller than the substantially square opening formed when the resin plate bodies 21 and 2 of the frame 20 are laminated, and the outer shape. It is a dimension.

Further, the anode electrode layer AE and the force sword electrode layer CE are configured such that each surface side is covered with carbon cloth CC formed of conductive fibers. This carbon cross CC uniformly supplies the fuel gas or oxidant gas supplied into the gas conduction space to each electrode layer, and the electricity generated by the electrode reaction is applied to the collector 12. It will be supplied efficiently. That is, since the carbon cloth CC is in a fibrous form, the supplied gas is more uniformly diffused by conducting between the fibers. In addition, since the carbon cloth CC has electrical conductivity, the generated electricity can flow efficiently to the collector 12. If necessary, the carbon cross CC can be omitted.

The single cell is formed by sequentially laminating the separator body 11, the collector 12, the frame 20, and the ME A 30. More specifically, as shown in FIG. 6, ME A 30 is placed between two upper and lower frames 20 that are rotated approximately 90 degrees in the same plane, and an adhesive or the like is used, for example. By coating, the ME A 30 electrolyte membrane EF is sandwiched between the frames 20 and fixed together.

The collector 12 is housed in the housing holes 21 c and 22 c of each frame 20 with respect to the integrally fixed frame 20 and ME A 30. At this time, the collector 12 is disposed in the collector 12 in the direction of arrangement of the pair of through holes 21 a and 21 b (through holes 22 a and 22 b) formed in the frame 20 to be accommodated, that is, the conduction direction of the introduced gas. The first concave and convex portions 12 a and the second concave and convex portions 12 b are accommodated in the accommodating holes 21 c and 22 c of the frame 20 so as to coincide with the arrangement direction of the second concave and convex portions 12 b.

Then, for example, by applying an adhesive or the like, the housing holes 21 c, 2 of the frame 20 2 With the collector 12 housed in the c, the separator body 11 is fixed to the frame 20 integrally. At this time, since the plate thickness of the resin plate main bodies 2 1 and 2 2 is slightly smaller than the molding height of the collector 12 2, the collector 12 is slightly pressed to the ME A 3 0 side by the separator main body 1 1. It is assembled in the state. As a result, the contact state between the collector 12 and ME A 30 (more specifically, carbon cloth CC) can be kept good. Then, a plurality of single senores formed in this way are stacked according to the required output to constitute a fuel cell stack.

In the fuel cell stack configured as described above, as shown in FIG. 1, the gas inlets 1 1 a of the separator main body 1 1 and the gas outlets 1 1 b of the separator body 11 are flared between the stacked single cells. In this state, all the holes 20 1 a and 2 1 b and the through holes 2 2 a and 2 2 b are connected to each other. For this reason, in the following description in the present specification, the gas passages formed by the gas inlet 11a of each unit cell and the through holes 21a, 22a of the frame 20. The communication path formed by the two Honored, the gas outlet 1 1 b and the through-holes 2 1 b and 2 2 b of the frame 20 is called a gas exhaust liner two-hold.

When fuel gas or oxidant gas is supplied from the outside through this gas supply inner manifold, the supplied fuel gas or oxidant gas is introduced into the gas conduction space. The fuel gas or oxidant gas introduced in this way is circulated by being uniformly diffused in the gas conduction space by the collector 12.

More specifically, the gas introduced from the gas supply inner hold into the gas conduction space flows toward the gas discharge inner hold while contacting the collector 12 arranged in the gas conduction space. Here, the collector 12 has the first concavo-convex molded portion 1 2 a, the flat plate portion 1 2 c and the second concavo-convex molded portion 1 2 b with respect to the arrangement direction of the gas supply inner manifold and the gas discharge inner manifold hold. Is going to be self-contained continuously.

For this reason, the fuel gas or oxidant gas introduced into the gas conduction space from the gas supply inner hornored is, as shown schematically in FIG. Then, the flow is formed in a three-dimensional manner by meandering the flow path formed by the flat plate portion 1 2 c toward the second concavo-convex molded portion 1 2 b. This will be specifically described below.

When the gas introduced into the gas conduction space reaches the collector 12, the gas is projected on the upper surface (or the lower surface) of the ME A 30 and the first uneven portion 1 2 a and the second uneven portion 1 2 b. Department ( (Hereinafter, this gap is referred to as ME A side passage), and the lower surface (or upper surface) of the separator body 11, the first concavo-convex molded portion 1 2 a, and the second concavo-convex component. It circulates in a gap formed by the concave portion (or convex portion) in the shape portion 1 2 b (hereinafter, this gap is referred to as a separator main body side passage). Here, in order to simplify the following explanation and make it easy to understand, an example in which the collector gas 12 and the separator main body 11 are laminated on the upper surface side of the ME A 30 and the fuel gas flows is described as an example. To do.

First, the fuel gas distribution in the M E A side passage will be described. When the fuel gas flows into the MEA side channel 形成 formed by the convex portion of the first uneven formed portion 1 2 a, as shown by the broken line in FIG. The second concavo-convex molded part 1 2 b flows toward the ME A side passage formed by the convex part.

That is, the convex portions of the first concavo-convex molded portion 12 a and the second concavo-convex molded portion 12 b have their respective top portions protruding from the upper surface of the flat plate portion 12 c by the thickness. For this reason, the fuel gas that has flowed in the vicinity of the top of the convex portion in the first concave-convex shaped portion 12a collides with the side surface of the flat plate portion 12c, and the second concave-convex shaped portion 12b is linearly distributed in the b direction. Is prohibited. Therefore, the fuel gas that has flowed into the ME A-side passage formed by the first concavo-convex molded portion 12 a is ME A 30 side, that is, the convex portion in the convex portion of the first concavo-convex molded portion 12 a. Flows toward the second concavo-convex molded portion 1 2 b. In other words, the fuel gas circulates in a space formed between the ME A 30 and the flat plate portion 12 c (hereinafter, this space is referred to as a gap space).

Here, the molding cycle of the concave and convex portions in the first concave and convex molded portion 12 a and the molding cycle of the concave and convex portions in the second concave and convex molded portion 12 b differ from each other by a half cycle. In addition, in the concave portions of the first concavo-convex molded portion 12 a and the second concavo-convex molded portion 12 b, their respective bottom portions protrude from the lower surface of the flat plate portion 12 c by the plate thickness.

For this reason, the fuel gas that has flowed into the gap space across the convex portion of the first concave-convex molded portion 12 a collides with the side surface of the bottom of the concave portion in the second concave-convex molded portion 12 b, and the adjacent first fourth Convex forming part 1 2 Distribution in the a direction is prohibited. Therefore, the fuel gas that has passed through the MEA-side passage formed by the convex portions of the first concave / convex molded portion 12 a is formed by the convex portions of the second concave / convex molded portion 12 b through the gap space. It circulates while meandering towards the ME A side passage.

-On the other hand, when the fuel gas flows into the separator main body side passage formed by the concave portion of the first concavo-convex molded portion 1 2 a, as shown by the solid line in FIG. 2 c By, it flows toward the separator main body side channel | path formed by the recessed part of the 2nd uneven | corrugated molded part 1 2b. .

In other words, as described above, the convex portions of the first concavo-convex molded portion 12 a and the second concavo-convex molded portion 12 b protrude from the upper surface of the flat plate portion 12 c by the thickness of the plate. For this reason, the fuel gas that has passed through the separator body side passage formed by the concave portion of the first concave portion molding portion 12a collides with the side surface of the top portion of the convex portion in the second concave / convex molding portion 12b, Second concavo-convex molded part 1 2 Distribution in the b direction is prohibited. Therefore, the fuel gas that has flowed into the space formed between the separator body 11 and the flat plate portion 1 2 c passes through the second concavo-convex molded portion 1 2 b formed on both sides of the collided convex portion. It flows toward.

Here, in the collector 12, as shown in FIG. 7, there is a portion where the first uneven formed portion 12 a is formed adjacent to the second uneven formed portion 12 b. For this reason, in this part, the convex part of the first concave / convex molding part 12a is formed adjacent to the concave part of the second concave / convex molding part 12b, and the convex part of the second concave / convex molding part 12b is formed. Adjacent to this, a concave portion of the first concave-convex forming portion 12 2 a is formed. That is, at the portion where the second HA convex molded portion 1 2 b and the first concave / convex molded portion 1 2 a are adjacent to each other at the collector 12, the concave portion and the convex portion (the convex portion and the concave portion ) Forms a relatively large opening. For this reason, when the fuel gas flowing through the separator body side passage passes through the second concavo-convex molded portion 12 b, it passes through the formed opening in the direction of the ME side passage (below the collector 12 shown in FIG. 7). Direction) and merge with the fuel gas flowing through the ME A side passage. On the other hand, when the fuel gas flowing through the MEA-side passage passes through the second convex projection portion 12 b, the separator body-side passage direction (upper side of the collector 12 shown in FIG. 7) passes through the formed opening. Direction) and merge with the fuel gas flowing through the separator body side passage.

Therefore, the fuel gas introduced into the gas conduction space passes through the collector 12 and circulates in a three-dimensional meandering in the vertical and horizontal directions. As a result, the fuel gas can be diffused well in the gas conduction space, and is efficiently supplied to the anode electrode layer AE.

In the above description, the case where the collector gas 12 and the separator body 11 are laminated on the upper surface side of the ME A 30 and the fuel gas is conducted is described as an example. However, the case where the oxidant gas is conducted is explained. Even so, it is exactly the same. Even when the collector 12 and the separator body 11 are stacked on the lower surface side of the ME A 30, the first unevenness of the collector 12 in the above example is formed. The fuel gas or the oxidant gas flows in exactly the same way, except that the shape portion 12a and the second concavo-convex molded portion 12b are different in the concave or convex portions.

Here, in the MEA 30 constituting the polymer electrolyte fuel cell, as is well known, the anode electrode layer AE or the force sword electrode layer CE is formed by an electrode reaction using a fuel gas and an oxidant gas! Water is produced at More specifically, for example, ME A 30 electrolyte membrane EF is formed from an ion exchange membrane that selectively permeates cation. ¾ ^ is a force sword electrode according to the following chemical reaction formulas 1 and 2. Water is produced in layer CE.

Node electrode layer: H ₂ → 2H ⁺ + 2e— · · 'Chemical reaction formula 1

Cathode electrode layer: 2H ++ 2e + (1/2) 0 ₂ → H ₂ 0 · · 'Chemical reaction formula 2

Further, for example, in order for the electrolyte membrane EF of MEA 30 to be formed from an ion exchange membrane that selectively permeates anion, water is generated in the anode electrode layer A E according to the following chemical reaction formulas 3 and 4.

Anode electrode layer: H ₂ + 20H— → 2H ₂ 0 + 2e—

Cathode electrode layer: (l / 2) 0 ₂ + H ₂ 0 + 2e— → 20H— · Chemical reaction formula 4

As described above, when a large amount of generated water is generated in the anode electrode layer AE or the force sword electrode layer CE, the supply of the fuel gas or the oxidant gas is hindered, that is, a flooding state may occur. In the situation in which this flooding state occurs, the generated water covers the surface of the anode electrode layer AE or the force sword electrode layer CE, and passes through the carbon cross CC to reach the collector 12 1 ”. The generated water that has reached the concave portion and the convex portion in the first concave-convex molded portion 12 a or the second concave-convex molded portion 12 b formed in the collector 12 due to the surface tension forms a water film. It becomes like this.

Incidentally, the collector 12 can conduct the gas introduced into the gas conduction space three-dimensionally as described above. That is, the collector 12 has a first concavo-convex molded portion 12a, a second concavo-convex molded portion 12b and a flat plate portion 12c continuously formed, and the first concavo-convex molded portion 12a and The second concavo-convex molded portion 12 b is accommodated in the frame 20 so that the arrangement direction thereof is substantially parallel to the gas conduction direction. As a result, the fuel gas or the oxidant gas introduced into the gas conduction space inevitably has the concave or convex portions of the first concavo-convex molded portion 12 a and the second concavo-convex molded portion 12 b formed on the collector 12. Pass across the section.

Therefore, the electrode reaction in ME A 30 progresses, and the first concavo-convex molded part 1 2 a and the second Even in a situation where a flooding state occurs to such an extent that the concave or convex portion in the concavo-convex molded portion 12 b is blocked by the water film of the generated water, it is introduced into the gas conduction space from the gas supply inner hold. Thus, the formation of a water film is prevented by the flow of gas discharged from the gas discharge inner manifold. Furthermore, since the fuel gas or oxidant gas is introduced at a predetermined pressure, the generated water that has reached the collector 12 is discharged together with some unreacted gas into a single cell, that is, outside the fuel cell stack. .

In this way, the generated water that has reached the collector 12 is drained to the outside, so that, for example, the electrolyte membrane EF is retained in the generated water existing in the vicinity of the anode electrode layer AE or the force sword electrode layer CE. Excess water other than water reaches continuously near the collector 12 via the carbon cloth CC, and this generated water (surplus water) force S is discharged. Such water film formation prevention and generated water drainage are continuously performed when the fuel cell is in operation, that is, as long as fuel gas and oxidizer gas are supplied.

Therefore, while the fuel cell is in operation, no water is collected in the collector 12, and no extra water is collected in the anode electrode layer AE or the cathode electrode layer CE. Can be satisfactorily prevented. In addition, since the generated water is continuously drained outside the fuel cell stack during the operation of the fuel cell, a single cell after stopping the operation of the fuel cell, more specifically, the anode electrode layer AE or the cathode electrode layer CE The amount of produced water remaining in the collector 1 2 can be extremely reduced. As a result, for example, even when the fuel cell is installed in an environment where the temperature is low (below 0 ° C), it is possible to prevent the generated water from icing and reducing the gas supply rate. It is possible to ensure good startability of the fuel cell in a low temperature environment.

As can be understood from the above description, according to the first embodiment, the flat plate portion 1 2 c formed on the collector 12 2 forms the flow path of the fuel gas or the oxidant gas. Fuel from the gap formed by the concave portion (convex portion) of the molded portion 1 2 a toward the gap formed by the flange portion (concave portion) of the second concave-convex molded portion 1 2 b facing this concave portion (convex portion) The flow of gas or oxidant gas can be hindered. That is, the fuel gas or the oxidant gas is projected from the gap formed by the concave portion (convex portion) of the first concave-convex molded portion 12 a by the flat plate portion 12 c. ) Concave part (convex part) formed adjacent to the convex part (K1 part) in this second concave-convex molded part 1 2 b without passing linearly toward the gap formed by ) Meanders towards the gap formed by As a result, the fuel gas or the oxidant gas is well diffused by meandering from the first concave and convex molding portion 12 a to the second concave and convex molding portion 1 2 b to constitute ME A 30. Sufficient fuel gas or oxidant gas can be supplied to the anode electrode layer AE or the force sword electrode layer CE. Therefore, good gas supply performance can be ensured, and the amount of unreacted fuel gas or oxidant gas that is not consumed by ME A 30 can be reduced.

In addition, the fuel gas or the oxidant gas separated by the separator main body 1 1 is a gap formed by the concave portion or the convex portion of the first rib convex molding portion 12 a and the concave portion of the second concave and convex molding portion 12 b. Passes across the gap formed by the convex portion and is supplied to the anode electrode layer AE or the force sword electrode layer CE. For this reason, for example, when the generated water generated by the action of surface tension reaches the vicinity of the collector 12, the generated water can be discharged together with unreacted gas on the flow of fuel gas or oxidant gas. it can. As a result, as long as the fuel gas and the oxidizing gas are supplied, in other words, as long as the solid polymer battery is operating, the generated water can be drained continuously. Therefore, it is possible to ensure good drainage performance of the generated water.

Furthermore, the first concavo-convex molded part 1 2 a, the flat plate part 1 2 c and the second concavo-convex molded part 1 b are successively formed in this order so that the fuel gas or the oxidant gas can be applied to the first concavo-convex molded part 1 2 a In addition, it is possible to increase the number of times of passing through the second concave-convex molded portion 1 2 b, that is, the number of times of meandering, and to distribute the fuel gas or the oxidant gas in a three-dimensional manner. For this reason, fuel gas or oxidant gas can be diffused better, and good gas supply performance can be ensured. In addition, by forming a plurality of first concavo-convex molded parts 1 2 a and second HA convex molded parts 1 2 b, the water generated by the electrode reaction in ME A 30 can be more easily brought near collector 12. Since it reaches a low level, it is possible to ensure better drainage performance of the generated water. In the first embodiment, the flat plate portion 12 c is used as the flow path forming portion, and the first concavo-convex forming portion 1 2 a of the fuel gas or the oxidant gas is used. The flow path to b was formed. However, as described above, in order to make the flat plate portion 1 2 c into a flat plate shape, in other words, the first uneven formed portion 1 2 a and the second uneven formed portion 1 2 are selected for the flat plate-shaped material. Therefore, the forming heights of the first uneven portion 12 a and the second uneven portion 12 b are limited. That is, in the first embodiment, the shearing process is locally applied to the material. Further, the degree of processing increases because of the stretching process. For this reason, in order to perform good molding, the material characteristics of the raw materials for these processes (for example, the flow characteristics of the material) must be taken into account, and the molding height must be limited.

Therefore, a description will be given of a second embodiment in which the collector 12 can be molded without the need to provide such molding restrictions. In describing the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

In this second embodiment, as shown in FIG. 8, instead of the flat plate portion 12c of the collector 12 in the first embodiment, a three-dimensional curved surface as a three-dimensionally formed flow path forming portion Part 1 2 d differs in that it is adopted. As shown in FIGS. 9 (a) and (b), the three-dimensional curved surface portion 1 2 d includes a convex portion in the first uneven portion 12 a and a bottom portion of the concave portion in the second uneven portion 1 2 b. And a curved surface that connects the bottom of the concave portion in the first concave-convex molded portion 12 a and the top of the convex portion in the second concave-convex molded portion 12 b.

Here, such a three-dimensional curved surface portion 12 d can be formed simultaneously with the formation of the concave portion and the convex portion in the first concave-convex molding portion 12 a and the concave portion and the convex portion in the second concave-convex molding portion 12 b. it can. That is, in the second embodiment, the processing area for the material can be increased. For this reason, for example, the fluidity of the raw material at the time of processing can be sufficiently secured, and good molding can be performed. Therefore, it is not necessary to strictly set restrictions associated with the molding of the first concavo-convex molded part 1 2 a, the second concavo-convex molded part 1 2 b, and the three-dimensional curved surface part 1 2 d.

Then, the collector 12 having such a three-dimensional curved surface portion 12 d is also integrally joined to the separator body 11 and fixed integrally as in the first embodiment. The frame 20 and the ME A 30 are accommodated in the accommodation holes 21c and 22c to form a single cell. Here, the collector 12 in the second embodiment also has the first concavo-convex molded portion 1 2 a and the second concavo-convex molded portion 1 2 b with respect to the arrangement direction of the gas supply inner manifold and the gas discharge inner manifold hold. Are accommodated in the receiving holes 2 1 c and 2 2 c of the frame 20 so that the arrangement directions of the two are substantially parallel to each other. .

In the second embodiment, the fuel gas or the oxidant gas introduced into the gas conduction space from the gas supply inner hold is the first of the collector 12 as schematically shown in FIG. The uneven formed portion 1 2 a flows in a three-dimensional manner by meandering the flow path formed by the three-dimensional curved surface portion 1 2 d toward the second uneven formed portion 1 2 b from the force. This will be explained in detail below. . In this description as well, in the same way as in the above embodiment, in order to facilitate understanding, the collector 12 and the separator body 11 are laminated on the upper surface side of the ME A 30 and the fuel gas flows. explain.

First, fuel gas distribution in the ME A side passage will be described. When the fuel gas flows into the ME A-side passage formed by the convex portions of the first concavo-convex molded portion 1 2 a, as shown by the broken line in FIG. 2d flows toward the MEA-side passage formed by the convex portions of the second concave-convex molded portion 12b.

That is, the three-dimensional curved surface portion 1 2 d has a curved surface connecting the top of the convex portion of the first concave-convex molded portion 1 2 a and the bottom portion of the concave portion of the second concave-convex molded portion 1 2 b and the first concave-convex molded portion 1 2 It is formed from a curved surface connecting the bottom of the concave portion of a and the top of the convex portion of the second four-convex molded portion 1 2 b. For this reason, the fuel gas that has flowed into the convex portion of the first ridge convex molding portion 12 a flows in the ME A 30 direction along the lower surface of the three-dimensional curved surface portion 12 d in FIG. That is, the fuel gas that has flowed into the convex portion of the first concave-convex shaped portion 12 a is connected to the bottom of the concave portion of the three-dimensional curved surface portion 1 2 d force S second concave-convex molded portion 12 b, so that the second Unevenness forming part 1 2 Distribution in the b direction is prohibited.

Then, the fuel gas that has reached ME A 30 flows toward the convex portions formed on both sides of the concave portion of the second concave-convex molded portion 12 b. As a result, the fuel gas that has passed through the MEA-side passage formed by the convex portions of the first concave-convex molded portion 12 a is transferred to the MEA-side passage formed by the convex portions of the second concave-convex molded portion 12 b. It circulates while meandering.

On the other hand, when the fuel gas flows into the separator main body side passage formed by the concave portion of the first concavo-convex molded portion 12 2a, as shown by the actual spring in FIG. It flows toward the separator body 11 along the upper surface of the three-dimensional curved surface portion 1 2 d shown in 0. That is, the fuel gas that has flowed into the concave portion of the first concave-convex molded portion 12 a is connected to the top of the convex portion of the second concave-convex molded portion 1 2 b because the three-dimensional curved surface portion 1 2 d is connected to the second concave-convex portion. Molding part 1 2 Distribution in the b direction is prohibited. Then, the fuel gas that has reached the separator body 11 flows toward the recesses formed on both sides of the top of the second concavo-convex molded part 1 2.

Here, in the collector 12 in the second embodiment, as shown in FIG. 10, a portion where the first concavo-convex molded portion 1 2 a is formed as the second concavo-convex molded portion 12 b is formed. Exists. That is, the convex portion of the first concave / convex molded portion 12a is formed adjacent to the concave portion of the second concave / convex molded portion 12b, and the first concave / convex molded portion adjacent to the convex portion of the second concave / convex molded portion 12b. Recessed part 1 2 a is formed . Therefore, also in the collector 12 in the second embodiment, in the portion where the second concavo-convex molded portion 1 2 b and the first concavo-convex molded portion 1 2 a are adjacent to each other, the concave portion and the convex portion (the convex portion and A relatively large opening is formed by the recess).

For this reason, also in the collector 12 in the second embodiment, when the fuel gas flowing through the separator main body side passage passes through the second concavo-convex molding portion 12 b, the ME A side passage is formed through the formed opening. It flows three-dimensionally in the direction (downward direction of collector 12 shown in FIG. 10) and merges with the fuel gas flowing through the ME A side passage. On the other hand, when the fuel gas flowing through the MEA-side passage passes through the second concavo-convex molded portion 12 b, the separator body-side passage direction (upper side of the collector 12 shown in FIG. 10) passes through the formed opening. Direction) and merge with the fuel gas flowing through the separator body side passage.

Therefore, also in the second embodiment, the fuel gas introduced into the gas conduction space passes through the collector 12 and circulates in a three-dimensional meandering in the vertical and horizontal directions. As a result, the fuel gas can diffuse well in the gas conduction space, and is efficiently supplied to the anode electrode layer AE. In the example in the second embodiment, when the oxidant gas is conducted, or when the collector 12 and the separator main body 11 are stacked on the lower surface side of the ME A 30, the collector 12 in the above example is used. The other parts are exactly the same except that the first concavo-convex molded part 1 2 a and the second concavo-convex molded part 12 b are different in the concave or convex parts. Also in the collector 12 in the second embodiment, the fuel gas or oxidant gas introduced into the gas conduction space inevitably has the first uneven formed portion 12 a formed in the collector 12 and the first 2 Passes so as to cross the concave or convex portion of the concave and convex molded portion 1 2 b. Therefore, as in the first embodiment, even when the electrode reaction in ME A 30 proceeds and a flooding state occurs, a water film is formed by the flow of fuel gas or oxidant gas. Is prevented. Furthermore, since the fuel gas or the oxidant gas is introduced at a predetermined pressure, the generated water that has reached the collector 12 is discharged together with some unreacted gas to the outside of the single cell, that is, the fuel cell stack.

Therefore, as in the first embodiment, while the fuel cell is in operation, the generated water does not collect in the collector 12, and excessive generation occurs in the anode electrode layer AE or the force sword electrode layer CE. Since water does not accumulate, the occurrence of flooding can be prevented well. Also, during operation of the fuel cell, the generated hydropower S is continuously drained out of the fuel cell stack. Therefore, for example, the generated water can be prevented from freezing even in a low temperature environment, and good startability of the fuel cell can be ensured.

As can be understood from the above description, since the second embodiment does not perform local molding, it is not necessary to provide molding restrictions. Therefore, since the collector 12 can be molded very easily, the yield is improved, and as a result, the manufacturing cost can be reduced. In addition, since there is no need to provide molding restrictions, the design flexibility of the collector 12 is improved. As a result, for example, a design that reduces the pressure loss of the fuel gas or oxidant gas that conducts in the gas conduction space can also reduce the thickness of the collector 12 and reduce the size of the fuel cell itself. .

The three-dimensional curved surface portion 12 d connects the top of the convex portion of the second concave-convex molded portion 12 formed at a position opposite to the bottom of the concave portion in the first concave-convex molded portion 12 a, It is possible to connect the bottom of the concave portion of the second concave-convex molded portion 1 2 formed at a position facing the top of the convex portion in the first concave-convex molded portion 1 2 a. Accordingly, the flow of the fuel gas or the oxidant gas from the gap formed by the concave portion in the first concave / convex molded portion 12a to the gap formed by the convex portion in the second concave / convex molded portion 12b, and The flow of fuel gas or oxidant gas is surely prohibited from the gap formed by the convex part in the first concave / convex molding part 12a to the gap formed by the concave part in the second concave / convex molding part 12b. can do.

Further, the bottom of the concave portion (the convex portion) in the first concave-convex shaped portion 12 a and the top of the convex portion (bottom of the concave portion) in the second concave-convex shaped portion 1 2 b are formed by the three-dimensional curved surface portion 1 2 d By connecting, the contact mode with ME A 30 (carbon cloth CC) can be made linear. As a result, the gas supply performance to ME A 30, more specifically the anode electrode layer A E or the force sword electrode layer CE, can be further improved, and the power generation performance of the fuel cell itself can be improved. Other effects are the same as in the first embodiment.

In carrying out the present invention, the present invention is not limited to the first embodiment and the second embodiment, and various modifications can be made.

For example, the shape of the four parts of the first concavo-convex molded part 1 2 a and the second concavo-convex molded part 12 b in the collector 12 and the shape of the convex part is substantially rectangular in cross section in the first and second embodiments. It is not limited to shape. That is, any shape may be used as long as the fuel gas or the oxidant gas can pass therethrough. In the first and second embodiments, the separator main body 11 and the collector 12 are joined together in a metallic manner so as to be integrally fixed. Needless to say, this can be implemented without metallic joining of the separator body 11 and the collector 12.

Claims

The scope of the claims

1. In a fuel cell separator that supplies an externally introduced fuel gas and an oxidant gas to an electrode layer constituting an electrode structure of a fuel cell,

A flat separator body that separates the fuel gas and the oxidant gas to prevent mixed flow; and the fuel gas or the oxidant gas separated by the separator body is diffused and supplied to the electrode structure. And a collector that collects electricity generated by an electrode reaction in the electrode structure,

A plurality of turning portions and projections that form gaps between the separated fuel gas or the oxidant gas in a three-dimensional manner between the separator body and the electrode structure are linearly formed. The first concavo-convex molded part,

It differs from the molding cycle of the concave and convex portions of the first concavo-convex molded portion by a half cycle, and a gap for the three-dimensional flow of the separated fuel gas or oxidant gas is provided in the separator main body. And a second concavo-convex molded portion formed by linearly and continuously molding a plurality of concave portions and convex portions formed between the electrode structure and the electrode structure,

Formed between the first concavo-convex molded portion and the second concavo-convex molded portion to connect the first concavo-convex molded portion and the second concavo-convex molded portion to each other, and the separated fuel gas Alternatively, the flow path from the gap formed by the turning portion of the first concavo-convex molding portion to the gap formed by the concave portion of the second concavo-convex molding portion and the convex portion of the first concavo-convex molding portion And a collector having a flow path forming portion that forms a flow path from the formed gap to the gap formed by the convex portion of the second concavo-convex molded portion. Separator.

2. The fuel cell separator described in claim 1

The 酉 S row direction of the first concavo-convex molded portion and the second concavo-convex molded portion is substantially parallel to the flow direction of the fuel gas or oxidant gas separated by the separator body. Fuel cell separator.

3. In the fuel cell separator according to claim 1,

The flow path forming part is

A bottom portion of the concave portion forming the first concave-convex molded portion and a concave portion forming the second concave-convex molded portion. A fuel cell formed between a flat surface including a bottom and a flat surface including a top of a convex portion forming the first concave / convex molding portion and a top portion of a convex portion forming the second concave / convex molding portion. Separator for use.

4. In the fuel cell separator according to claim 3,! /,

The flow path forming part is

Forming the first concave and convex portions, forming the concave portion forming the second concave and convex portions, forming the convex portions forming the first concave and convex portions, and forming the second concave and convex portions. A separator for a fuel cell, characterized in that it is formed into a flat plate shape including at least a neutral surface with respect to the forming direction of the convex portion.

5. In the fuel cell separator according to claim 4,

For the flow path forming part formed into the flat plate shape,

The bottom part of the concave part forming the first concave-convex molded part and the bottom part of the concave part forming the second concave-convex molded part protrude by the thickness of the bottom part, and the top part of the convex part forming the first concave-convex molded part and A fuel cell separator characterized in that the tops of the projections forming the second concavo-convex molded part protrude by the thickness of the tops.

6. In the fuel cell separator according to claim 3,

The flow path forming part is

The bottom of the concave portion and the top of the convex portion that form the first concave-convex molded portion, and the top portion of the convex portion that forms the second concave-convex molded portion and faces the concave portion of the first concave-convex molded portion, and the first concave-convex molded portion A separator for a fuel cell, characterized in that it is formed into a three-dimensional curved surface that connects the bottom of the concave portion facing the convex portion of the portion.

7. The fuel cell separator according to claim 1,

The fuel cell separator, wherein the concave and convex portions forming the first concave and convex portions and the convex and concave portions in the molding direction are substantially rectangular.

8. The fuel cell separator according to claim 1, wherein

The collector for a fuel cell, wherein the collector is formed by continuously forming a plurality of the first concavo-convex forming part, the flow path forming part and the second concavo-convex forming part against J jet.