JP4924829B2 - Fuel cell separator - Google Patents

Description

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

  A polymer electrolyte fuel cell generally includes an electrode structure including an anode electrode layer formed on one surface side of an electrolyte membrane and a cathode electrode layer formed on the other surface side. In the polymer electrolyte fuel cell, fuel gas (for example, hydrogen gas) and oxidant gas (for example, air) are supplied from the outside to the anode electrode layer and the cathode electrode layer, respectively. As a result, an electrode reaction occurs in the electrode structure and power is generated. 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 the oxidant gas necessary for the electrode reaction to the electrode structure.

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

  For example, the following Patent Document 1 discloses a fuel cell that employs a separator composed of a thin flat plate-like substrate and a net-like conductor. The mesh-like conductor in this conventional fuel cell is made of, for example, expanded metal or metal lath having diamond-shaped slits. The mesh-shaped 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 path formed in a substantially rectangular shape, and is supplied to the anode electrode layer or the cathode electrode layer through the diamond-shaped slit. Thus, the gas supply efficiency is improved by supplying the fuel gas or the oxidant gas.

Also, for example, Patent Document 2 below discloses a fuel cell separator that can improve the gas supply efficiency of the separator. The fuel cell separator includes a flat plate-shaped first member (carbon) and a plurality of layers stacked on the first member to elastically contact the anode electrode layer and the cathode electrode layer and to form a gas flow path. It is comprised from the 2nd member (metal plate) in which the protrusion was formed. In this conventional fuel cell separator, the fuel gas and the oxidant gas passing therethrough are turbulent by passing through the gas flow path formed by the plurality of protrusions of the second member. It has become. As a result, the fuel gas and the oxidant gas supplied into the gas flow path can be diffused satisfactorily by passing three-dimensionally in all directions, and the gas supply efficiency to the anode electrode layer and the cathode electrode layer is improved. It is like that.
JP 2005-209470 A JP 2002-184422 A

  By the way, in the mesh-like conductor shown in the above-mentioned patent document 1 and the second member shown in the above-mentioned patent document 2, the gas flow formed by the gas flow path and the projecting piece formed in a substantially rectangular cross section. For example, the path may be substantially parallel to the direction connecting the inlet for introducing the fuel gas and the oxidant gas into the interior and the outlet for leading the introduced gas to the outside. For this reason, the gas inlet formed and the outlet can be in a linear communication state by the formed gas flow path. As a result, part of the introduced fuel gas and oxidant gas is diffused by the meshes and protrusions formed on the conductor and consumed by the anode electrode layer and the cathode electrode layer, but the other part is diffused. In other words, there is a possibility of being discharged outside without being consumed. Thus, in the situation where the fuel gas and the oxidant gas discharged without being consumed, that is, the unreacted gas increases, the power generation efficiency in the fuel cell cannot be improved.

  In the 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 cathode electrode layer according to the ion exchange characteristics of the electrolyte membrane. Generate. The generated water (generated water) covers, for example, the surface of the anode electrode layer or the cathode electrode layer, or adheres to the mesh of the conductor of Patent Document 1 or the protrusion of the second member of Patent Document 2. By doing so, the good supply of fuel gas or oxidant gas may be impaired. 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, for example, in an environment having a low temperature atmosphere, fuel gas or oxidant gas is not sufficiently supplied due to freezing of generated water remaining inside, As a result, the low temperature startability of the fuel cell may be deteriorated. For this reason, the water produced by the electrode reaction needs to be efficiently discharged to the outside.

  The present invention has been made to solve the above-described problems, and the object is to achieve both good supply performance of fuel gas and oxidant gas and good drainage performance of generated water generated by electrode reaction. The object is to provide a fuel cell separator.

In order to achieve the above object, a feature of the present invention is a fuel cell separator that supplies an externally introduced fuel gas and oxidant gas to an electrode layer constituting an electrode structure of a fuel cell. A separator body for separating the fuel gas and the oxidant gas to prevent mixed flow; and a fuel gas or an oxidant gas separated by the separator body is diffused and supplied to the electrode structure. A collector for collecting electricity generated by an electrode reaction in the electrode structure, wherein the separated fuel gas or oxidant gas flows in three dimensions through the separator body and the electrode structure A first concavo-convex molded portion formed by linearly and continuously forming a plurality of concave portions and convex portions formed between the body and the concave and convex portions of the first concavo-convex molded portion. A plurality of recesses and projections differing by a half cycle with respect to the molding cycle and forming a gap for the three-dimensional flow of the separated fuel gas or oxidant gas between the separator body and the electrode structure. a second concave-convex mold portion and linearly and continuously molding the parts, similar between the first concave-convex mold portion and the second concave-convex shaped portion, the bottom of the recess forming the first uneven shaping unit And a plane including the bottom of the concave portion forming the second concavo-convex molded portion, and a plane including the top of the convex portion forming the first concavo-convex molded portion and the top of the convex portion forming the second concavo-convex molded portion. A gap formed between the first concavo-convex molding portion and the second concavo-convex molding portion and formed by a recess of the separated fuel gas or oxidant gas in the first concavo-convex molding portion. To the recess of the second concavo-convex molded part Forming a flow path to the gap formed by the convex portion of the first concavo-convex molded portion and a gap formed by the convex portion of the second concavo-convex molded portion. A first concavo-convex molding part or the second concavo-convex molding part, the flow path forming part, the second concavo-convex molding part or the first concavo-convex molding part, the first concavo-convex molding part or the second concavo-convex part. The second concavo-convex molded part or the first concavo-convex molded part and the first concavo-convex molded part are sequentially and successively formed in the order of the molded part, the flow path forming part, the second concavo-convex molded part, or the first concavo-convex molded part. It exists in having comprised from the collector in which an opening is formed in the part which a shaping | molding part or the said 2nd uneven | corrugated shaping | molding part adjoins .

  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 has a first concave-convex forming portion and a second concave-convex forming portion in which the molding cycles of the plurality of concave portions and the convex portions are different from each other by a half cycle in order to form a gap for three-dimensionally flowing the fuel gas or the oxidant gas. Further, the fuel gas or the oxidant gas that has passed through the gap formed by the concavo-convex part of the first concavo-convex molded part has a concavo-convex molded part toward the gap formed by the concavo-convex part of the second concavo-convex molded part. It can have a flow path formation part which forms a flowing flow path. Here, the flow path forming unit is configured such that the separated fuel gas or oxidant gas is changed from the gap formed by the recesses of the first concavo-convex molding part, which is different by a half cycle, to the gap formed by the recesses of the second concavo-convex molding part. A flow path that circulates from a gap formed by the convex portions of the first concavo-convex molded portion to a gap formed by the convex portions of the second concavo-convex molded portion can be formed.

  As described above, the flow path forming portion forms the flow path of the fuel gas or the oxidant gas, so that the concave portion (the convex portion) is opposed to the gap formed by the concave portion (the convex portion) of the first concave / convex forming portion. The flow of the fuel gas or the oxidant gas toward the gap formed by the convex portion (concave portion) of the second concavo-convex molded portion can be inhibited. 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 molding portion toward the gap formed by the convex portion (concave portion) of the second concave / convex molding portion. Without passing through, the second meandering portion circulates in a meandering manner toward a gap formed by a concave portion (convex portion) formed adjacent to the convex portion (concave 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 molded portion, and is sufficiently diffused to provide sufficient fuel for the electrode layers constituting the electrode structure. 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.

  In addition, the fuel gas or the oxidant gas separated by the separator body crosses the gap formed by the concave or convex portion of the first concave / convex molding portion and the gap formed by the concave or convex portion of the second concave / convex molding portion. And supplied to the electrode layer constituting the electrode structure. For this reason, for example, when the produced water generated by the action of the surface tension reaches the vicinity of the collector, the produced water can be drained to the outside together with the unreacted gas on the flow of the fuel gas or the oxidant gas. Thereby, as long as the fuel gas and the oxidant gas are supplied, in other words, as long as the solid polymer fuel cell is operating, the generated generated water can be continuously drained. Therefore, good drainage performance of generated water can be ensured.

  In this case, the arrangement direction of the first concavo-convex molded portion and the second concavo-convex molded portion may be substantially parallel to the flow direction of the fuel gas or the oxidant gas separated by the separator body.

  According to this, the introduced fuel gas or oxidant gas inevitably has a gap formed by the recesses and projections of the first concavo-convex molding part and a gap formed by the recesses and projections of the second concavo-convex molding part. Can be distributed across the street. As a result, fuel gas or oxidant gas circulates through the collector, inevitably diffusing to ensure good gas supply performance, and inevitably ensuring good drainage performance of generated water as the gas is discharged it can.

  Moreover, it is good for the shape in the shaping | molding direction of the recessed part and convex part which each form a said 1st uneven | corrugated shaping | molding part and a 2nd uneven | corrugated shaping | molding part in a substantially rectangular shape. According to this, the first concavo-convex molded portion and the second concavo-convex molded portion can be formed very easily without performing special processing separately. 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, it is possible to increase the number of times that the fuel gas or the oxidant gas passes through the gap formed by the second concavo-convex molding part from the gap formed by the first concavo-convex molding part, that is, the number of times of meandering. 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 more favorably, 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 can more easily reach the vicinity of the collector. The drainage performance can be ensured.

  Another feature of the present invention is that the flow path forming portion includes a flat surface including a bottom portion of the concave portion that forms the first concave-convex molded portion and a bottom portion of the concave portion that forms the second concave-convex molded portion, and the first It may be formed between the top of the convex part forming the concave / convex molding part and the plane including the top part of the convex part forming the second concave / convex molding 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, a convex portion that forms the first concave-convex molded portion, and It is good to shape | mold into a flat plate shape including at least the neutral surface with respect to the shaping | molding direction of the convex part which forms the said 2nd uneven | corrugated shaping | molding part. Further, in this case, with respect to the flow path forming portion formed into the flat plate shape, the bottom portion of the concave portion forming the first concave / convex forming portion and the bottom portion of the concave portion forming the second concave / convex forming portion are the bottom portions. It is good to project by the plate | board thickness in this, and make the top part of the convex part which forms the said 1st uneven | corrugated molded part, and the top part of the convex part which forms the said 2nd uneven | corrugated molded part protrude by the plate | board thickness in these top parts.

  According to these, the plane including the bottoms of the recesses forming the first concavo-convex molded part and the second concavo-convex molded part, and the plane including the tops of the convexes forming the first concavo-convex molded part and the second concavo-convex molded part In the meantime, a plate-shaped flow path forming part can be formed. More specifically, the plate-shaped flow path forming portion is formed by forming the concave portion forming the first concave-convex forming portion and the second concave-convex forming portion and the convex portion forming the first concave-convex forming portion and the second concave-convex forming portion. The neutral plane with respect to the molding direction, that is, the bottom of the concave portion forming the first concave and convex portion and the top portion of the convex portion forming the first concave and convex portion and the second concave and convex portion. It can be shaped to include a neutral surface in the middle.

  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 portion (substantially equally divided when the flow path forming portion 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 first concavo-convex molded portion The gap between the bottom of the recess and the flow path forming portion becomes narrow, and the fuel gas or the oxidant gas does not easily flow. Similarly, for example, when the fuel gas or the oxidant gas flows from the convex portion of the first concave-convex molded portion toward the opposing second concave-convex molded portion, it flows between the top of the convex portion in the first concave-convex molded portion. The space between the path forming portion is narrowed and the fuel gas or the oxidant gas is less likely to flow.

  As a result, the portion where the fuel gas or the oxidant gas is more easily circulated, specifically, the lower side of the convex portion or the upper side of the concave portion in the first concavo-convex molded portion in the gap divided by the flow path forming portion. Will be distributed preferentially. Similarly, in the second concavo-convex molded portion, the fuel gas or the oxidant gas is more easily circulated, more specifically, in the gap divided by the flow path forming portion, The upper part of the recess is preferentially distributed. Thereby, the fuel gas or the oxidant gas is formed between the upper side of the gap formed by the recesses of the first concavo-convex molding part and the recesses of the second concavo-convex molding part, which are different from each other by a half cycle by the flow path forming part. Between the upper sides of the gaps, or between the lower side of the gap formed by the convex portions of the first concavo-convex molded portion and the lower side of the gap formed by the convex portions of the second concavo-convex molded portion. . 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 ensured.

  Further, the bottom of the concave portion of the first concavo-convex molded portion and the bottom of the concave portion of the second concavo-convex molded portion is protruded by the plate thickness with respect to the flat channel forming portion, and the convex portion and the second concavo-convex portion of the first concavo-convex molded portion are projected. The top part of the convex part of the molding part can be projected by the thickness. Thereby, for example, when the fuel gas or oxidant gas that has circulated through the lower side of the gap formed by the convex portion in the first concave-convex molded portion reaches the concave portion in the second concave-convex molded portion formed at a position facing it. The fuel gas or oxidant gas collides with the bottom side surface of the recess. That is, the fuel gas or the oxidant gas flowing through the lower side of the gap formed by the projections in the first concavo-convex molding part is effectively prohibited from passing linearly through the recesses in the second concavo-convex molding part. be able to. Therefore, in this case, the fuel gas or the oxidant gas can be more meandered, the gas supply efficiency can be improved, and good drainage of the generated water can be ensured.

  In addition, the flow path forming portion includes a bottom portion of the concave portion and the top portion of the convex portion forming the first concave and convex portion, and a convex portion that forms the second concave and convex portion and faces the concave portion of the first concave and convex portion. It is good to shape | mold into the three-dimensional curved surface which connects the top part of a part, and the bottom part of the recessed part facing the convex part of a said 1st uneven | corrugated shaping | molding 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 molded part formed at a position facing the bottom part of the concave part in the first concave-convex molded part, The bottom part of the recessed part of the 2nd uneven | corrugated shaped part shape | molded in the position facing the top part of the convex part in a 1st uneven | corrugated shaped part can be connected. Thereby, 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 portion in the first concave-convex molded portion Thus, the flow of the fuel gas or the oxidant gas from the gap formed by the gap to the gap formed by the recess in the second concavo-convex molded portion can be reliably prohibited.

  In other words, the flow path forming part formed on the three-dimensional curved surface causes the fuel gas or the oxidant gas to flow 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. The flow of fuel gas or oxidant gas from the flow and the gap formed by the convex portions of the first concavo-convex molded portion to the gap formed by the convex portions of the second concavo-convex molded portion can be reliably formed. As a result, the fuel gas or the oxidant gas is formed by the flow path forming portion by the gap formed by the concave portion of the first concave / convex molding portion and the concave portion of the second concave / convex molding portion that differ from each other by a half cycle, or the first concave / convex molding. The gap formed by the convex part of the part and the convex part of the second concavo-convex molded part can snake and circulate. 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 ensured.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a part of a polymer electrolyte fuel cell stack configured 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 formed by laminating a plurality of single cells including two separators 10 and a frame 20 and a MEA 30 (Membrane-Electrode Assembly) arranged between the separators 10 and stacked. The

  For example, when a fuel gas such as hydrogen gas and an oxidant gas such as air are introduced from the outside of the fuel cell stack to each single cell, power is generated by an electrode reaction occurring in the MEA 30. 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 uniformly diffuses the separator main body 11 that prevents the mixed flow of the gas introduced into the fuel cell stack and the fuel gas or the oxidant gas supplied from the outside into the MEA 30. And a collector 12 that collects electricity generated by the electrode reaction.

  The separator body 11 is formed from a metal thin plate (for example, a stainless plate having a thickness of about 0.1 mm) as a material. In addition, as a raw material which forms the separator main body 11, the steel plate etc. which gave anti-corrosion processing, such as gold plating, etc. can be employ | adopted elsewhere, for example. Further, 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 inlet 11a and a gas outlet 11b opposed to the gas inlet 11a are formed at the peripheral portion thereof. Two pairs consisting of are formed. Each pair is formed so as to be substantially orthogonal to each other.

  The gas introduction port 11a is formed as a substantially oblong through hole, and introduces a fuel gas or an oxidant gas supplied from the outside of the fuel cell stack into the single cell, and other stacked single cells. The fuel gas or oxidant gas supplied to the gas is circulated. The gas outlet 11b is also formed as a substantially oblong through hole, and out of the gas introduced into the single cell, the MEA 30 discharges unreacted gas to the outside, and other stacked single cells. Circulate unreacted gas from

  The collector 12 is made of a flat material (for example, a stainless plate having a thickness of about 0.1 mm). Then, as schematically shown in FIG. 3, the collector 12 was formed by continuously cutting a part of the material so that a concave portion and a convex portion having a substantially rectangular cross section were formed in the plate width direction of the raw material. A first concave-convex molding portion 12a, and a concave portion formed in the first concave-convex molding portion 12a, and a concave portion having a substantially rectangular cross section in the plate width direction of the material by a molding cycle different from the molding cycle of the convex portion by a half cycle It has the 2nd uneven | corrugated shaping | molding part 12b by which the convex part was continuously shape | molded. More specifically, for example, as shown in FIG. 4A, the concave and convex portions in the first concave-convex molded portion 12a are formed into concave portions, convex portions, concave portions, convex portions, etc. from the left side of the drawing. In the case of molding, the concave and convex portions in the second concavo-convex molding portion 12b are molded with a molding cycle from the left side to the convex, concave, convex, concave, etc. as shown in FIG. 4B. The

  The collector 12 connects the first concavo-convex molded portion 12a and the second concavo-convex molded portion 12b, which are formed with a predetermined interval in the longitudinal direction of the material, to each other, and the second concavo-convex molded portion 12a through the second concavo-convex molded portion 12a. It has a flat plate part 12c as a flow path forming part for forming a gas flow path to the concave-convex forming part 12b.

  As shown in FIG. 5A, the flat plate portion 12c is a distance between a virtual plane including the bottom of the concave portion and a virtual plane including the top of the convex portion in the first concave and convex portion 12a and the second concave and convex portion 12b. It is molded so as to include a surface (neutral surface) located approximately in the middle of (the molding height dimension). And as shown in FIG.5 (b), the top part of the convex part in the 1st uneven | corrugated shaping | molding part 12a and the 2nd uneven | corrugated shaping | molding part 12b comes to protrude only the board | plate thickness from the upper surface of the flat plate part 12c, for example. ing. On the other hand, the bottom part of the recessed part in the 1st uneven | corrugated shaping | molding part 12a and the 2nd uneven | corrugated shaping | molding part 12b protrudes only the board | plate thickness from the lower surface of the flat plate part 12c, for example. In addition, about the shaping | molding height of the 1st uneven | corrugated shaping | molding part 12a and the 2nd uneven | corrugated shaping | molding part 12b, in order to maintain the favorable workability resulting from the material characteristic (for example, flow characteristic) of a raw material, it is a board | substrate of a raw material, for example. It is good to shape | mold to the shaping height of about 3 times or less with respect to thickness.

  And the collector 12 is comprised by shape | molding sequentially the 1st uneven | corrugated shaping | molding part 12a, the flat plate part 12c, and the 2nd uneven | corrugated shaping | molding part 12b with respect to the raw material in order in the longitudinal direction of a raw material.

  The collector 12 configured in this manner 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. And the contact part of the separator main body 11 and the collector 12 is metal-bonded by the brazing method, for example, and is integrally fixed.

  More specifically, first, a paste-like brazing material such as copper or nickel is thinly applied to one side of the collector 12. And the collector 12 which apply | coated the brazing material is temporarily fixed to the predetermined position of the separator main body 11. FIG. At this time, the collector 12 has an arrangement direction of the pair of gas inlets 11a and gas outlets 11b formed in the separator main body 11, and an arrangement direction of the first concavo-convex molding part 12a and the second concavo-convex molding part 12b in the collector 12. Are temporarily fixed to match. Next, the temporarily fixed separator body 11 and collector 12 are heated at a predetermined temperature for a predetermined time in a reducing gas atmosphere, and then cooled. Thereby, the separator main body 11 and the collector 12 are joined metallically and fixed integrally.

  Here, the joining method for metallicly 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, for example, 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 21 and 22 having the same structure, and each of the two separators 10 (more specifically, the separator body 11) has its own structure. One side is fixed. The resin plate main bodies 21 and 22 have an outer dimension substantially the same as the outer dimension of the separator main body 11 and a thickness slightly smaller than the molding height of the collector 12. And with respect to the resin plate main body 21, the resin plate main body 22 rotates and arrange | positions about 90 degree | times in the same plane direction, and is laminated | stacked. The resin plate bodies 21 and 22 can employ various resin materials, and preferably glass epoxy resins.

  Further, the resin plate main bodies 21 and 22 have the same peripheral edge portions as the positions corresponding to the through holes of the gas inlet 11a and the gas outlet 11b formed in the separator main body 11 in a state where a single cell is formed. Through holes 21a and 21b and through holes 22a and 22b having substantially the same shape as each through hole are formed. The resin plate main bodies 21 and 22 are provided with receiving holes 21c and 22c for receiving the collector 12 joined to the separator main body 11 at substantially the center part thereof. The accommodating holes 21c and 22c are formed through a pair of gas inlet 11a and gas outlet 11b formed in the separator body 11 to be fixed, and the other resin plate body 21 or resin plate body 22 stacked. It is formed so as to accommodate the holes 21a, 21b or the through holes 22a, 22b.

  Thus, by forming the accommodation holes 21c and 22c, the lower surface (or upper surface) of the separator body 11 to be fixed, the inner peripheral surface of the accommodation hole 21c (or accommodation hole 22c), and the upper surface (or lower surface) of the MEA 30. A space (hereinafter, this space is referred to as a gas conduction space) is formed. For example, the fuel gas can be introduced into the gas conduction space from one gas introduction port 11a, and the oxidant gas can be introduced from the other gas introduction port 11a and the through hole 21a. Further, the unreacted gas that has passed through the gas conduction space can be led out to the outside through one gas outlet 11b and through the other gas outlet 11b and the through hole 21b.

  As shown in FIGS. 1 and 6, the MEA 30 as an electrode structure is formed by laminating an electrolyte membrane EF and a predetermined catalyst in layers on the electrolyte membrane EF, and a fuel gas is introduced. The main components are an anode electrode layer AE arranged in the gas conduction space and a cathode electrode layer CE arranged in the gas conduction space into which the oxidant gas is introduced. Note that the actions (electrode reactions) of the electrolyte membrane EF, the anode electrode layer AE, and the cathode electrode layer CE are widely known and are not directly related to the present invention. Therefore, detailed descriptions thereof are omitted in the following description. .

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 an anion (more specifically, Is formed from an ion exchange membrane (for example, Neoceptor (registered trademark) manufactured by Tokuyama Corporation) that selectively transmits hydroxide ions (OH ⁻ ). The electrolyte membrane EF is larger than the substantially square opening formed when the resin plate main bodies 21 and 22 of the frame 20 are laminated, and the through-hole is formed in a state where the resin plate main bodies 21 and 22 are laminated. 21a, 21b and the through-holes 22a, 22b are formed in a size that does not block. Thus, by forming the electrolyte 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)), a hydrogen storage alloy, or the like. A layer is formed on the surface of the EF. The anode electrode layer AE and the cathode electrode layer CE formed in a layer shape have slightly smaller external dimensions than the substantially square opening formed when the resin plate bodies 21 and 22 of the frame 20 are laminated. Has been.

  In addition, the anode electrode layer AE and the cathode electrode layer CE are configured such that the respective surface sides are covered with carbon cloth CC formed of conductive fibers. The carbon cloth CC uniformly supplies fuel gas or oxidant gas supplied into the gas conduction space to each electrode layer, and efficiently supplies electricity generated by the electrode reaction to the collector 12. To do. That is, since the carbon cloth CC is fibrous, the supplied gas is more uniformly diffused by conducting between the fibers. In addition, since the carbon cloth CC has conductivity, the generated electricity can be efficiently flowed to the collector 12. If necessary, the carbon cloth CC can be omitted.

  And a single cell is formed by laminating | stacking the separator main body 11, the collector 12, the flame | frame 20, and MEA30 one by one. More specifically, as shown in FIG. 6, the MEA 30 is disposed between the upper and lower two frames 20 that are disposed by being rotated approximately 90 degrees in the same plane, and, for example, an adhesive is applied. Accordingly, the electrolyte membrane EF of the MEA 30 is sandwiched between the frames 20 and is integrally fixed.

  The collector 12 is accommodated in the accommodating holes 21c and 22c of each frame 20 with respect to the integrally fixed frame 20 and MEA 30. At this time, the collector 12 is arranged in the arrangement direction 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, and the first uneven forming in the collector 12. It accommodates in the accommodation holes 21c and 22c of the flame | frame 20 so that the arrangement direction of the part 12a and the 2nd uneven | corrugated shaping | molding part 12b may correspond.

  Then, for example, by applying an adhesive or the like, the separator body 11 is integrally fixed to the frame 20 in a state where the collector 12 is accommodated in the accommodation holes 21 c and 22 c of the frame 20. At this time, since the plate thickness of the resin plate main bodies 21 and 22 is slightly smaller than the molding height of the collector 12, the collector 12 is assembled in a state of being slightly pressed by the separator main body 11 toward the MEA 30 side. Thereby, the contact state between the collector 12 and the MEA 30 (more specifically, the carbon cloth CC) can be kept good. And the single cell formed in this way constitutes a fuel cell stack by laminating a plurality according to demand output.

  In the fuel cell stack configured as described above, as shown in FIG. 1, the gas inlets 11 a and the gas outlets 11 b of the separator body 11 are connected to the through holes 21 a and 21 b of the frame 20 between the stacked single cells. And it will be in the state which all communicated through through-hole 22a, 22b. For this reason, in the following description in the present specification, the gas supply inner manifold, the gas outlet 11b, and the frame 20 are connected to the communication path formed by the gas inlet 11a of each single cell and the through holes 21a and 22a of the frame 20. The communication passage formed by the through holes 21b and 22b is referred to as a gas discharge inner manifold.

  When fuel gas or oxidant gas is supplied from the outside via the 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 uniformly in the gas conduction space by the collector 12.

  More specifically, the gas introduced into the gas conduction space from the gas supply inner manifold flows toward the gas discharge inner manifold while being in contact with the collector 12 disposed in the gas conduction space. Here, in the collector 12, the first concavo-convex molding portion 12a, the flat plate portion 12c, and the second concavo-convex molding portion 12b are continuously arranged with respect to the arrangement direction of the gas supply inner manifold and the gas discharge inner manifold. Yes.

  For this reason, the fuel gas or oxidant gas introduced into the gas conduction space from the gas supply inner manifold is changed from the first concavo-convex molding portion 12a to the second concavo-convex molding portion 12b of the collector 12 as schematically shown in FIG. Toward, the flow path formed by the flat plate portion 12c meanders and flows three-dimensionally. This will be specifically described below.

  When the gas introduced into the gas conduction space reaches the collector 12, the gas is formed by the upper surface (or lower surface) of the MEA 30 and the convex portions (or concave portions) of the first concave and convex molding portions 12a and the second concave and convex molding portions 12b. Formed by a gap (hereinafter, this gap is referred to as an MEA-side passage), and a lower surface (or upper surface) of the separator body 11 and a concave portion (or convex portion) in the first concavo-convex molded portion 12a and the second concavo-convex molded portion 12b. Circulates in a gap (hereinafter, this gap is referred to as a separator body side passage). Here, in order to simplify the following description and facilitate understanding, the case where the collector 12 and the separator body 11 are laminated on the upper surface side of the MEA 30 and the fuel gas flows will be described as an example.

  First, the fuel gas distribution in the MEA side passage will be described. When the fuel gas flows into the MEA side passage formed by the convex portions of the first concave / convex molding portion 12a, the fuel gas that has flowed in is formed into the second concave / convex molding by the flat plate portion 12c as shown by a broken line in FIG. It flows toward the MEA side passage formed by the convex part of the part 12b.

  That is, as for the convex part of the 1st uneven | corrugated shaping | molding part 12a and the 2nd uneven | corrugated shaping | molding part 12b, each of these top parts protrudes by plate | board thickness from the upper surface of the flat plate part 12c. For this reason, the fuel gas that has flowed into the vicinity of the top of the convex portion in the first concavo-convex molded portion 12a collides with the side surface of the flat plate portion 12c, and linear circulation in the direction of the second concavo-convex molded portion 12b is prohibited. Therefore, the fuel gas that has flowed into the MEA side passage formed by the first concavo-convex molded portion 12a faces the MEA 30 side of the convex portion of the first concavo-convex molded portion 12a, that is, the lower side of the convex portion toward the second concavo-convex molded portion 12b. Flowing. In other words, the fuel gas flows in a space formed between the MEA 30 and the flat plate portion 12c (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 molding portion 12a and the molding cycle of the concave and convex portions in the second concave and convex molding portion 12b differ from each other by a half cycle. Moreover, as for the recessed part of the 1st uneven | corrugated shaping | molding part 12a and the 2nd uneven | corrugated shaping | molding part 12b, these each bottom part protrudes only board | plate thickness from the lower surface of the flat plate part 12c.

  For this reason, the fuel gas that has flowed into the gap space across the convex portion of the first concavo-convex molded portion 12a collides with the side surface of the bottom portion of the concave portion in the second concavo-convex molded portion 12b, and is adjacent to the first concavo-convex molded portion 12a. Distribution to is prohibited. Therefore, the fuel gas that has passed through the MEA side passage formed by the convex portion of the first concave / convex molding portion 12a is directed toward the MEA side passage formed by the convex portion of the second concave / convex molding portion 12b via the gap space. Circulate 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 molding portion 12a, as shown by a solid line in FIG. It flows toward the separator main body side passage formed by the concave portion of the concave-convex molding portion 12b.

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

  Here, in the collector 12, as shown in FIG. 7, there is a portion where the first concavo-convex forming portion 12a is formed adjacent to the second concavo-convex forming portion 12b. For this reason, in this part, the convex part of the 1st uneven | corrugated shaped part 12a is shape | molded adjacent to the recessed part of the 2nd uneven | corrugated shaped part 12b, and 1st uneven | corrugated shaping | molding is adjacent to the convex part of the 2nd uneven | corrugated shaped part 12b. A concave portion of the portion 12a is formed. That is, in the collector 12, a relatively large opening is formed by the concave portion and the convex portion (the convex portion and the concave portion) in a portion where the second concave and convex portion 12b and the first concave and convex portion 12a are adjacent to each other.

  For this reason, when the fuel gas flowing through the separator main body side passage passes through the second concavo-convex molding portion 12b, the fuel gas is tertiary in the MEA side passage direction (downward direction of the collector 12 shown in FIG. 7) through the formed opening. Originally flows and merges with the fuel gas flowing through the MEA side passage. On the other hand, when the fuel gas flowing through the MEA side passage passes through the second concavo-convex molding portion 12b, the fuel gas passes through the formed opening and is three-dimensionally in the separator body side passage direction (upward direction of the collector 12 shown in FIG. 7). The fuel gas flowing through the separator main body side passage is joined.

  Therefore, the fuel gas introduced into the gas conduction space passes through the collector 12 and flows while meandering three-dimensionally in the vertical and horizontal directions. Thus, 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 main body 11 are stacked on the upper surface side of the MEA 30 and the fuel gas is conducted is described as an example, but the same applies even when the oxidant gas is conducted. It is. Further, even when the collector 12 and the separator body 11 are laminated on the lower surface side of the MEA 30, only the recesses or protrusions of the first unevenness forming portion 12a and the second unevenness forming portion 12b of the collector 12 in the above example are different. The fuel gas or oxidant gas flows in exactly the same way.

Here, in the MEA 30 constituting the solid polymer fuel cell, as is well known, water is generated in the anode electrode layer AE or the cathode electrode layer CE by an electrode reaction using a fuel gas and an oxidant gas. Specifically, for example, when the electrolyte membrane EF of the MEA 30 is formed of an ion exchange membrane that selectively permeates cations, water is generated in the cathode electrode layer CE according to the following chemical reaction formulas 1 and 2. .
Anode electrode layer: H ₂ → 2H ⁺ + 2e ⁻ … chemical reaction formula 1
Cathode electrode layer: 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O… chemical reaction formula 2

For example, when the electrolyte membrane EF of the MEA 30 is formed of an ion exchange membrane that selectively permeates anions, water is generated in the anode electrode layer AE according to the following chemical reaction formulas 3 and 4.
Anode electrode layer: H ₂ + 2OH ⁻ → 2H ₂ O + 2e ⁻ … chemical reaction formula 3
Cathode electrode layer: (1/2) O ₂ + H ₂ O + 2e ⁻ → 2OH ⁻ … chemical reaction formula 4

  As described above, when a large amount of generated water is generated in the anode electrode layer AE or the cathode electrode layer CE, a state where the supply of the fuel gas or the oxidant gas is inhibited, that is, a flooding state may occur. In the situation where the flooding state occurs, the generated water covers the surface of the anode electrode layer AE or the cathode electrode layer CE and passes through the carbon cloth CC to reach the collector 12. Then, the generated water that has reached the collector 12 penetrates into the concave and convex portions of the first concavo-convex molding portion 12a or the second concavo-convex molding portion 12b formed in the collector 12 by the surface tension so as to form a water film. become.

  Incidentally, the collector 12 can conduct the gas introduced into the gas conduction space three-dimensionally as described above. In other words, the first concavo-convex forming portion 12a, the second concavo-convex forming portion 12b, and the flat plate portion 12c are continuously formed on the collector 12, and the arrangement direction of the first concavo-convex forming portion 12a and the second concavo-convex forming portion 12b is formed. Is accommodated in the frame 20 so as to be substantially parallel to the gas conduction direction. As a result, the fuel gas or the oxidant gas introduced into the gas conduction space inevitably crosses the recesses or protrusions of the first unevenness forming part 12a and the second unevenness forming part 12b formed in the collector 12. pass.

  Therefore, the electrode reaction in the MEA 30 proceeds, and the flooding state is generated to such an extent that the concave portions or the convex portions in the first concave / convex molding portion 12a and the second concave / convex molding portion 12b are blocked by the water film of the generated water. In addition, the formation of a water film is prevented by the flow of gas introduced from the gas supply inner manifold into the gas conduction space and discharged from the gas discharge inner manifold. Further, since the fuel gas or the oxidant gas is introduced at a predetermined pressure, the generated water that has reached the collector 12 is drained out of the single cell, that is, the fuel cell stack together with some unreacted gas.

  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 cathode electrode layer CE. Surplus water continuously reaches the vicinity of the collector 12 via the carbon cloth CC, and this generated water (surplus water) is drained. Such water film formation prevention and generated water drainage are continuously performed when the fuel cell is in operation, in other words, as long as fuel gas and oxidant gas are supplied.

  Therefore, while the fuel cell is in operation, the generated water does not collect in the collector 12 and the excess generated water does not collect in the anode electrode layer AE or the cathode electrode layer CE. Can be prevented satisfactorily. Further, since the generated water is continuously drained outside the fuel cell stack during the operation of the fuel cell, the single cell after the operation of the fuel cell is stopped, more specifically, the anode electrode layer AE or the cathode electrode layer CE The amount of generated water remaining inside the collector 12 can be extremely reduced. Thereby, for example, even when the fuel cell is installed in an environment where the temperature is low (0 ° C. or lower), it is possible to prevent the generated water from freezing and the gas supply amount from being reduced. Good startability of the fuel cell in the environment can be ensured.

  As can be understood from the above description, according to the first embodiment, the flat plate portion 12c formed on the collector 12 forms the flow path of the fuel gas or the oxidant gas. Flow of fuel gas or oxidant gas from the gap formed by the concave portion (convex portion) toward the gap formed by the convex portion (concave portion) of the second concave-convex forming portion 12b facing the concave portion (convex portion) Can be inhibited. In other words, the fuel gas or the oxidant gas is formed by the flat plate portion 12c from the gap formed by the concave portion (convex portion) of the first concave / convex molding portion 12a and the gap formed by the convex portion (concave portion) of the second concave / convex molding portion 12b. Without passing linearly toward the surface, the second concavo-convex shaped portion 12b circulates meandering toward a gap formed by a concave portion (convex portion) formed adjacent to the convex portion (concave portion). As a result, the fuel gas or the oxidant gas is satisfactorily diffused by meandering and flowing from the first concavo-convex molded portion 12a toward the second concavo-convex molded portion 12b, and the anode electrode layer AE or the cathode electrode layer constituting the MEA 30 Sufficient fuel gas or oxidant gas can be supplied to the CE. Therefore, good gas supply performance can be ensured, and the amount of unreacted fuel gas or oxidant gas that is not consumed by the MEA 30 can be reduced.

  In addition, the fuel gas or the oxidant gas separated by the separator main body 11 is a gap formed by the recesses or projections of the first concavo-convex molding portion 12a and a gap formed by the recesses or projections of the second concavo-convex molding portion 12b. And is supplied to the anode electrode layer AE or the cathode electrode layer CE. For this reason, for example, when the generated water generated by the action of the surface tension reaches the vicinity of the collector 12, the generated water can be discharged together with the unreacted gas on the flow of the fuel gas or the oxidant gas. Thereby, as long as the fuel gas and the oxidant gas are supplied, in other words, as long as the solid polymer fuel cell is operating, the generated generated water can be continuously drained. Therefore, good drainage performance of generated water can be ensured.

  Further, the first concavo-convex forming portion 12a, the flat plate portion 12c, and the second concavo-convex forming portion 12b are successively formed in order, so that the fuel gas or the oxidant gas is changed from the first concavo-convex forming portion 12a to the second concavo-convex forming portion 12b. The number of times of passage, that is, the number of times of meandering can be increased, and fuel gas or oxidant gas can be distributed three-dimensionally. For this reason, fuel gas or oxidant gas can be diffused more favorably, and good gas supply performance can be ensured. In addition, by forming a plurality of the first concavo-convex molded portions 12a and the second concavo-convex molded portions 12b, the generated water generated by the electrode reaction in the MEA 30 can more easily reach the vicinity of the collector 12, and therefore, better generation Water drainage performance can be ensured.

  In the said 1st Embodiment, the flat plate part 12c as a flow path formation part is employ | adopted, and the flow path from the 1st uneven | corrugated shaping | molding part 12a of fuel gas or oxidant gas to the 2nd uneven | corrugated shaping | molding part 12b is formed. Carried out. However, as described above, in order to make the flat plate portion 12c into a flat plate shape, in other words, in order to selectively form the first concavo-convex molding portion 12a and the second concavo-convex molding portion 12b with respect to the flat plate-like material, The molding height of the first concavo-convex molded portion 12a and the second concavo-convex molded portion 12b is limited. That is, in the first embodiment, since the material is locally subjected to shearing and stretching, the degree of processing increases. For this reason, in order to perform favorable shaping | molding, the material characteristic (for example, flow characteristic of material) of the raw material with respect to these processes must be considered, It is necessary to restrict | limit a shaping | molding height.

  Therefore, a description will be given of a second embodiment in which the collector 12 can be molded without the need to provide such a restriction on molding. In the description of 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 the 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 portion 12d as a three-dimensionally formed flow path forming portion is provided. It differs in that it is adopted. As shown in FIGS. 9A and 9B, the three-dimensional curved surface portion 12d is a curved surface that connects the top of the convex portion in the first concave-convex molded portion 12a and the bottom portion of the concave portion in the second concave-convex molded portion 12b, and The curved surface connecting the bottom of the concave portion in the first concave / convex molded portion 12a and the top portion of the convex portion in the second concave / convex molded portion 12b is formed in a composite manner.

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

  The collector 12 having such a three-dimensional curved surface portion 12d is also integrally joined to the separator body 11 and integrally fixed to the frame 20 and the same as in the first embodiment. It is accommodated in the accommodating holes 21c and 22c of the MEA 30 to form a single cell. Here, also in the collector 12 in the second embodiment, the arrangement direction of the first concavo-convex forming part 12a and the second concavo-convex forming part 12b is substantially parallel to the arrangement direction of the gas supply inner manifold and the gas discharge inner manifold. Thus, it is accommodated in the accommodation holes 21c, 22c of the frame 20.

  In the second embodiment, the fuel gas or the oxidant gas introduced from the gas supply inner manifold into the gas conduction space is, as schematically shown in FIG. To the second concavo-convex molded portion 12b, the flow path formed by the three-dimensional curved surface portion 12d meanders and flows three-dimensionally. This will be specifically described below. In this description as well, the case where the collector 12 and the separator main body 11 are stacked on the upper surface side of the MEA 30 and the fuel gas flows is described by way of example in order to facilitate understanding, as in the above embodiment.

  First, the fuel gas distribution in the MEA side passage will be described. When the fuel gas flows into the MEA side passage formed by the convex portions of the first concavo-convex molded portion 12a, the fuel gas that has flowed in is secondly moved by the three-dimensional curved surface portion 12d as shown by a broken line in FIG. It flows toward the MEA side passage formed by the convex portion of the concave-convex molded portion 12b.

  That is, the three-dimensional curved surface portion 12d has a curved surface that connects the top of the convex portion of the first concavo-convex molded portion 12a and the bottom of the concave portion of the second concavo-convex molded portion 12b, the bottom of the concave portion of the first concavo-convex molded portion 12a, and the second. It forms from the curved surface which connects the top part of the convex part of the uneven | corrugated shaped part 12b. For this reason, the fuel gas which flowed into the convex part in the 1st uneven | corrugated shaping | molding part 12a distribute | circulates to MEA30 direction along the lower surface of the three-dimensional curved-surface part 12d in FIG. That is, the fuel gas that has flowed into the convex portion of the first concave / convex molding portion 12a flows in the direction of the second concave / convex molding portion 12b because the three-dimensional curved surface portion 12d is connected to the bottom of the concave portion of the second concave / convex molding portion 12b. Is prohibited.

  Then, the fuel gas that has reached the MEA 30 flows toward the convex portions formed on both sides of the concave portion of the second concave-convex molded portion 12b. Thus, the fuel gas that has passed through the MEA side passage formed by the convex portions of the first concave / convex molding portion 12a flows while meandering toward the MEA side passage formed by the convex portions of the second concave / convex molding portion 12b. .

  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 molding portion 12a, as shown by the solid line in FIG. It flows toward the separator body 11 along the upper surface of the portion 12d. That is, the fuel gas that has flowed into the concave portion in the first concave / convex molding portion 12a flows in the direction of the second concave / convex molding portion 12b because the three-dimensional curved surface portion 12d is connected to the top of the convex portion of the second concave / convex molding portion 12b. Is prohibited. And the fuel gas which reached | attained the separator main body 11 flows toward the recessed part shape | molded on the both sides of the top part of the 2nd uneven | corrugated shaping | molding part 12b.

  Here, in the collector 12 according to the second embodiment, as shown in FIG. 10, there is a portion where the first concavo-convex molded portion 12a is formed as the second concavo-convex molded portion 12b is formed. That is, the convex part of the first concave / convex molding part 12a is molded adjacent to the concave part of the second concave / convex molding part 12b, and the concave part of the first concave / convex molding part 12a is molded adjacent to the convex part of the second concave / convex molding part 12b. Is done. For this reason, also in the collector 12 in this 2nd Embodiment, in the part which the 2nd uneven | corrugated shaping | molding part 12b and the 1st uneven | corrugated shaping | molding part 12a adjoin each other, it is comparatively by a recessed part and a convex part (convex part and recessed part). A large opening is formed.

  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 12b, it passes through the formed opening in the MEA side passage direction (FIG. The fuel gas flows three-dimensionally (downward of the collector 12 shown in FIG. 10) and merges with the fuel gas flowing through the MEA side passage. On the other hand, when the fuel gas flowing through the MEA side passage passes through the second concavo-convex molding portion 12b, it passes through the formed opening and is three-dimensionally in the separator body side passage direction (upward direction of the collector 12 shown in FIG. 10). The fuel gas flowing through the separator main body side passage is joined.

  Therefore, also in the second embodiment, the fuel gas introduced into the gas conduction space flows through the collector 12 while meandering three-dimensionally in the vertical and horizontal directions. Thus, the fuel gas can be diffused well in the gas conduction space, and is efficiently supplied to the anode electrode layer AE. Also in the illustration in the second embodiment, when the oxidant gas is conducted, or when the collector 12 and the separator body 11 are laminated on the lower surface side of the MEA 30, the first uneven forming portion 12a of the collector 12 in the above illustration. And only the recessed part or convex part of the 2nd uneven | corrugated shaping | molding part 12b differs, and other parts are completely the same.

  Further, also in the collector 12 in the second embodiment, the fuel gas or the oxidant gas introduced into the gas conduction space inevitably has the first concavo-convex forming portion 12a and the second concavo-convex forming portion formed in the collector 12. It passes so as to cross the concave portion or convex portion of 12b. Therefore, similarly to the first embodiment, even when the electrode reaction in the MEA 30 proceeds and a flooding state occurs, the formation of a water film is prevented by the flow of the fuel gas or the oxidant gas. Further, since the fuel gas or the oxidant gas is introduced at a predetermined pressure, the generated water that has reached the collector 12 is drained out of the single cell, that is, the fuel cell stack together with some unreacted gas.

  Therefore, as in the first embodiment, while the fuel cell is operating, the generated water does not collect in the collector 12, and excess generated water accumulates in the anode electrode layer AE or the cathode electrode layer CE. Therefore, occurrence of flooding can be prevented satisfactorily. In addition, since the generated water is continuously drained outside the fuel cell stack during the operation of the fuel cell, for example, the generated water can be prevented from freezing even in a low temperature environment, and the fuel cell can be started well. Sex can be secured.

  As can be understood from the above description, in the second embodiment, there is no need to provide molding restrictions because local molding is not performed. Therefore, since the collector 12 can be molded very easily, the yield is improved, and as a result, the manufacturing cost can be reduced. Further, since there is no need to provide molding restrictions, the design freedom of the collector 12 is improved. As a result, for example, the fuel cell itself can be downsized by designing the shape that reduces the pressure loss of the fuel gas or the oxidant gas that is conducted in the gas conduction space and by reducing the thickness of the collector 12.

  The three-dimensional curved surface portion 12d connects the top of the convex portion of the second concave-convex molded portion 12b formed at a position facing the bottom of the concave portion in the first concave-convex molded portion 12a, and the first concave-convex molded portion 12a. The bottom part of the recessed part of the 2nd uneven | corrugated shaping | molding part 12b shape | molded in the position facing the top part of a convex part can be connected. Thereby, 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 first concave / convex molded portion 12a. It is possible to reliably inhibit the flow of fuel gas or oxidant gas from the gap formed by the convex portion in the gap to the gap formed by the concave portion in the second concavo-convex molded portion 12b.

  Furthermore, the bottom of the concave portion (the top of the convex portion) in the first concave / convex molding portion 12a and the top of the convex portion (the bottom portion of the concave portion) in the second concave / convex molding portion 12b are connected by the three-dimensional curved surface portion 12d, whereby the MEA 30 ( The contact mode with the carbon cloth CC) can be linear. Thereby, the gas supply performance to the MEA 30, more specifically, the anode electrode layer AE or the cathode 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 and second embodiments, and various modifications can be made.

  For example, the shape of the concave and convex portions of the first concave and convex molding portion 12a and the second concave and convex molding portion 12b in the collector 12 is not limited to the substantially rectangular cross section of the first and second embodiments. In other words, any shape may be used as long as fuel gas or oxidant gas can pass therethrough.

  Moreover, in the said 1st and 2nd embodiment, the separator main body 11 and the collector 12 were integrally fixed by carrying out metallic joining. However, it goes without saying that the present invention can be implemented without metallicly joining the separator body 11 and the collector 12.

FIG. 4 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. It is the schematic perspective view which showed the separator main body which comprises the separator of FIG. It is the schematic for demonstrating the collector of FIG. FIG. 4 is a schematic diagram for explaining a molding cycle of a concave portion and a convex portion of a first concave and convex portion and a second concave and convex portion in the collector of FIG. 3, and FIG. (B) shows the molding cycle of the concave and convex portions of the second concavo-convex molding portion with respect to the first concavo-convex molding portion of (a). FIG. 4 is a schematic diagram for explaining a 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. It is a schematic exploded perspective view for demonstrating the assembly | attachment state of the flame | frame and MEA shown in FIG. It is the schematic for demonstrating the three-dimensional meandering of the fuel gas or oxidant gas by the collector of FIG. It is a schematic diagram for demonstrating the collector which concerns on 2nd Embodiment of this invention. 9A and 9B are schematic diagrams for explaining a three-dimensional curved surface in the collector of FIG. 8, where FIG. 9A shows a cross section in the longitudinal direction of the collector, and FIG. 9B shows a cross section in the width direction of the collector. . It is the schematic for demonstrating the three-dimensional meandering of the fuel gas or oxidizing agent gas by the collector of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Separator, 11 ... Separator main body, 12 ... Collector, 12a ... 1st uneven | corrugated molded part, 12b ... 2nd uneven | corrugated molded part, 12c ... Flat plate part (flow path formation part), 12d ... Three-dimensional curved surface part (flow path formation) Part), 20 ... frame, 30 ... MEA

Claims (6)

In the fuel cell separator for supplying the fuel gas and the oxidant gas introduced from the outside to the electrode layer constituting the electrode structure of the fuel cell,
A flat separator body that separates the fuel gas and the oxidant gas to prevent mixed flow;
A fuel gas or an oxidant gas separated by the separator main body is diffused and supplied to the electrode structure, and the collector collects electricity generated by an electrode reaction in the electrode structure;
A plurality of concave portions and convex portions that form gaps between the separator main body and the electrode structure so as to allow the separated fuel gas or oxidant gas to flow three-dimensionally linearly and continuously. A molded first concavo-convex molded portion;
The separator main body and the electrode structure are different from each other by a half cycle with respect to the molding cycle of the concave and convex portions of the first concavo-convex molding portion, and the gap for allowing the separated fuel gas or oxidant gas to flow three-dimensionally. A second concavo-convex molded portion obtained by linearly and continuously molding a plurality of concave portions and convex portions formed between the body,
Boil between the second concave-convex molding portion and the first concave-convex mold portion, and a plane including the bottom of the recess forming the bottom and the second concave-convex shaping of the recess forming the first uneven shaping unit, the The first concavo-convex molded part and the second concavo-convex molded part formed between the top of the convex part forming the first concavo-convex molded part and the plane including the top part of the convex part forming the second concavo-convex molded part. And a flow path from the gap formed by the recessed portion of the first concavo-convex molded portion of the separated fuel gas or oxidant gas to the gap formed by the recessed portion of the second concavo-convex molded portion, and A flow path forming part that forms a flow path from a gap formed by the convex part of the first concavo-convex molded part to a gap formed by the convex part of the second concavo-convex molded part ,
The first concavo-convex molding part or the second concavo-convex molding part, the flow path forming part, the second concavo-convex molding part or the first concavo-convex molding part, the first concavo-convex molding part or the second concavo-convex molding part, the flow The path forming portion, the second uneven formed portion or the first uneven formed portion are sequentially and sequentially formed, and the second uneven formed portion or the first uneven formed portion and the first uneven formed portion or the first 2. A fuel cell separator comprising: a collector having an opening formed in a portion adjacent to a two-concave formed portion . The fuel cell separator according to claim 1,
The fuel cell separator, wherein an arrangement direction of the first concavo-convex molded portion and the second concavo-convex molded portion is substantially parallel to a flow direction of the fuel gas or the oxidant gas separated by the separator body. The fuel cell separator according to claim 1 ,
The flow path forming part is
The forming direction of the concave portion forming the first concave-convex forming portion and the concave portion forming the second concave-convex forming portion, and the convex portion forming the first concave-convex forming portion and the convex portion forming the second concave-convex forming portion. A separator for a fuel cell, characterized by being formed into a flat plate shape including at least a neutral surface with respect to a forming direction. In the fuel cell separator according to claim 3 ,
For the flow path forming part formed into the flat plate shape,
The bottom part of the concave part forming the first concavo-convex molded part and the bottom part of the concave part forming the second concavo-convex molded part protrude by the thickness of the bottom part, and the top part of the convex part forming the first concavo-convex molded part and the The top part of the convex part which forms a 2nd uneven | corrugated molded part protrudes only by the plate | board thickness in these top parts, The separator for fuel cells characterized by the above-mentioned. The fuel cell separator according to claim 1 ,
The flow path forming part is
The bottom part of the concave part and the top part of the convex part forming the first concave and convex part, and the top part of the convex part forming the second concave and convex part and facing the concave part of the first concave and convex part and the first concave and convex part A separator for a fuel cell, characterized in that the separator is molded into a three-dimensional curved surface that connects the bottom of the concave portion facing the convex portion of the portion. The fuel cell separator according to claim 1,
The fuel cell separator is characterized in that the concave and convex portions forming the first concavo-convex molded portion and the second concavo-convex molded portion are substantially rectangular in shape in the molding direction.

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