JP2006114414A - Gas diffusion supply member for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas diffusion supply member for a fuel cell excellent in mechanical strength in which gas is sufficiently supplied to an electrode for efficient power generation. <P>SOLUTION: The member faces a power generation element 100 of a fuel cell to diffuse and supply oxidizing gas and reducing gas. It comprises a flow path board 1 on which a plurality of gas flow paths 2 and 3 are provided side by side, with one end as an open end while the other end as a closed end. At least two pairs, a pair composed of gas flow paths of one for flow-in and the other for flow-out, are provided. The gas flow paths 2 and 3 of one of the pairs are formed with gas communication openings 4 and 5 which open at one surface of the flow path board 1, and the gas flow paths 2 and 3 of the remaining pairs are formed with the gas communication openings 4 and 5 which open at the other surface of the flow path board 1. Porous bodies 6 and 7 allow gas to transmit between the gas flow paths 2 and 3 and the power generation element 100. They supply gas toward the electrode surface of the power generation element 100, and allow the gas to remain for an extended period so that it is sufficiently supplied to the electrode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a gas diffusion supply member for a fuel cell, and more particularly to a gas diffusion supply member capable of realizing efficient power generation by sufficient gas supply to power generation elements constituting the fuel cell. It is.

As a gas diffusion supply member for a fuel cell, a hollow plate-like electrode substrate in which a large number of gas flow paths are formed is known (for example, see Patent Document 1). This electrode substrate is made of a porous material having gas permeability, and by varying the pore diameter and porosity in the thickness direction, the three-phase interface between the electrode, the electrolyte and the reaction gas is increased, This is intended to improve the output of the fuel cell.
JP-A-9-50812

  However, in the conventional electrode substrate as described above, since the gas flow direction in the gas flow path is along the surface of the electrode portion, sufficient gas does not permeate the electrode portion, and the power generation of the fuel cell The efficiency was not always sufficient. In addition, since the substrate itself is made of a porous material, if a gas flow path is provided inside the substrate, the mechanical strength of the substrate may decrease. However, since it is necessary to increase the thickness of the substrate in order to prevent breakage, there has been a problem that the stacking density when the fuel cell is stacked is reduced.

  The present invention has been made by paying attention to the above-described conventional problems, and the object of the present invention is to sufficiently supply gas to the power generation elements constituting the fuel cell, It is possible to provide a gas diffusion supply member for a fuel cell that can improve the power generation efficiency of the fuel cell, has excellent mechanical strength, and can increase the stacking density of the stack when the fuel cell is configured. is there.

  A gas diffusion supply member for a fuel cell according to the present invention is a member that diffusely supplies an oxidizing gas or a reducing gas facing a power generation element of a fuel cell, and has a plurality of ends with an open end and the other end closed. The gas flow path substrate is provided. The flow path substrate is formed of a material that is substantially non-gas permeable and can also function as a mechanical strength member. In addition, the plurality of gas flow paths are provided in a number that constitutes at least two sets, with the inflow gas flow path and the outflow gas flow path as a set.

  Then, a gas flow port that opens on one surface of the flow path substrate is provided in a part of the gas flow paths of the entire set, and the remaining gas flow path is formed on the other surface of the flow path substrate. By providing a gas flow port that opens, thereby diffusing and supplying gas toward the electrode surface of the power generation element, and further including a porous body that allows gas to pass between the gas flow path and the power generation element, The residence time of the gas between the gas diffusion supply member and the power generation element is increased.

  According to the gas diffusion supply member for a fuel cell of the present invention, it is possible to sufficiently supply gas to the power generation element constituting the fuel cell, and to improve the power generation efficiency of the fuel cell. In addition, since the mechanical strength is obtained by the flow path substrate and the gas is diffused and supplied to both sides of the flow path substrate, the fuel cell is configured by alternately stacking the gas diffusion supply member and the power generation element. In addition, the stacking density of the stack can be increased, and thereby the fuel cell can be reduced in size and output.

  Hereinafter, an embodiment of a gas diffusion supply member for a fuel cell according to the present invention will be described based on the drawings. The gas diffusion supply member shown in FIGS. 1 (a) and 1 (b) is a member that diffuses and supplies an oxidizing gas and a reducing gas facing the power generation element of the fuel cell, and has one end as an open end and the other end as a closed end. And a plurality of gas flow paths arranged in parallel.

  The flow path substrate 1 uses a plurality of cylindrical bodies 1a having a rectangular cross-section closed on one side, and these cylinders 1a are arranged in parallel and are hermetically bonded to each other, and each cylinder is integrated. A gas flow path is formed by the body 1a. The flow path substrate 1 is formed of a material such as a metal that is substantially not gas permeable, and also has a function as a mechanical strength member. In addition, the configuration composed of a plurality of cylinders 1a is advantageous in that it is easy to deal with changes in the number and length of the gas flow paths and is easy to manufacture.

The plurality of gas flow paths are provided as many as at least two sets, with the inflow gas flow path 2 and the outflow gas flow path 3 as a set. In this embodiment, there are four sets, that is, eight. The gas flow paths 2 and 3 have the following configurations (1) to (3) in the flow path substrate 1.
(1) Each gas flow path has the open end of the inflow gas flow path 2 directed to one end side of the flow path substrate 1 on the left side in FIG. 1 (a) and the flow on the right side in FIG. 1 (a). The open end of the outflow gas flow path 3 is arranged on the other end side of the road substrate 1.
(2) Each gas flow path has gas flow ports 4 for inflow and outflow that are opened in one of the four surfaces of the flow path substrate 1 (upper surface in FIG. 1) in two of the four gas flow paths. 5 and the remaining two sets of gas flow paths are provided with inflow and outflow gas circulation ports 4 and 5 that open on the other surface (lower surface in FIG. 1) of the flow path substrate 1.
(3) Each gas flow path includes a gas flow path having gas flow ports 4 and 5 that open on one surface (the upper surface in FIG. 1) of the flow path substrate 1, and the other surface of the flow path substrate 1 (FIG. 1). Gas flow passages having gas flow ports 4 and 5 that open on the lower surface are alternately arranged.

  That is, in FIG. 1B, each gas flow path includes a first inflow gas flow path 2 and a third outflow gas flow path 3 from the left side, and a second inflow gas flow path 2. And the fourth outflow gas flow path 3 are the second set, the fifth inflow gas flow path 2 and the seventh outflow gas flow path 3 are the third set, the sixth inflow gas flow path 2 and the eighth set. The fourth outflow gas flow path 3 is a fourth set, and upward and downward gas flow ports 4 and 5 are formed in the first and third set gas flow paths 2 and 3, respectively. Downward inflow and outflow gas circulation ports 4 and 5 are formed in the second and fourth gas passages 2 and 3, respectively.

  In this embodiment, for convenience, four gas channels are shown as a set of two, but the number of gas channels in the gas diffusion supply member of the present invention is one set for inflow and outflow. In this case, the number of gas flow ports 4 and 5 is different from each other, and the number of gas flow paths for inflow and outflow in the same group is not limited at all. In the case of the configuration, the first group and the third group may be the same group (one set of four), and the second group and the fourth group may be interpreted as the same group. It is also possible to make the number of gas flow paths 2 different from the number of outflow gas flow paths 3 or to combine gas flow paths having different cross-sectional areas.

  A plurality of (three in the illustrated example) inflow and outflow gas distribution ports 4 and 5 are formed at predetermined intervals in the longitudinal direction of the gas flow paths 2 and 3, and It is formed in a slit shape in the direction, and is arranged substantially evenly on the entire surface without uneven distribution on one surface and the other surface of the flow path substrate 1 by the arrangement of the gas flow paths 2 and 3 described above. Yes.

  The flow path substrate 1 supplies a reducing gas (fuel) to the first set and the third set of inflow gas flow paths 2 having the upward inflow gas flow ports 4 in the fuel cell to be described later, and is directed downward. The oxidizing gas (air) is supplied to the second and fourth inflow gas passages 2 having the inflowing gas circulation ports 4, and further gas is supplied between the gas passages 2 and 3 and the power generation element. The porous body 6 and 7 which permeate | transmit.

  The porous bodies 6 and 7 have a flat plate shape as shown in FIG. 1 (b), and are provided on the upper and lower surfaces of the flow path substrate 1, respectively. Here, the porous body 6 on the upper surface side of the flow path substrate 1, that is, the fuel electrode side of the power generation element, has a foam metal such as foam Ni, foam silver and platinum, or a cermet such as Ni-YSG and Ni-SDC. It is desirable to use this, and this makes it excellent in reduction resistance and water vapor resistance. On the other hand, the porous body 7 on the lower surface side of the flow path substrate 1, that is, the air electrode side of the power generation element, is sintered with a foam metal such as foam Ni, foam silver and foam platinum, or an air electrode material such as LSM and LSC. It is desirable to use the above-mentioned one, which makes it excellent in oxidation resistance.

  As shown in FIG. 1C, the gas diffusion supply member having the above-described structure is stacked with the power generation elements to constitute a fuel cell, and also has a function as a separator between the power generation elements. The fuel cell is a solid oxide fuel cell, and includes a conventionally known power generation element 100 in which an electrolyte layer 101 is sandwiched between an air electrode layer (upper side in the figure) 102 and a fuel electrode layer (lower side in the figure) 103. I have.

  In the fuel cell, gas diffusion supply members are arranged above and below the power generation element 100 so that the air electrode layer 102 and the fuel electrode layer 103 and the porous bodies 6 and 7 made of a material suitable for each layer face each other. By applying the glass seal G so as to include the peripheral portions of the upper and lower gas diffusion supply members and the outer peripheral portion of the power generation element 100, the space of the oxidizing gas and the space of the reducing gas are hermetically separated. The illustrated fuel cell has a minimum configuration capable of generating electric power, and an actual fuel cell has a power generation element 100 and a gas diffusion supply member stacked in multiple stages.

  In the fuel cell described above, when the oxidizing gas and the reducing gas are supplied to each inflow gas passage 2 of the gas diffusion supply device, these gases are circulated as shown by the arrows in FIG. The porous body 5, 6 passes through the porous body 5, 6 and is diffused and supplied to each electrode (102, 103), and then passes through the porous body 5, 6 and the outflow gas flow port 5 and flows out. And discharged outside the battery.

  At this time, in the gas diffusion supply member, the gas circulation ports 4 and 5 facing the power generation element 100 are evenly arranged, and gas flows in from the inflow gas circulation port 4, and therefore, along the electrode surface Since the gas is diffused and supplied toward the electrode surface with respect to the conventional one in which the gas is flowing, and the inflowing and outflowing gas is permeated through the porous bodies 5 and 6, The residence time of the gas with the gas diffusion supply member can be increased.

  As a result, in the fuel cell using the gas diffusion supply member, sufficient gas supply is performed over the entire surface of each electrode of the power generation element 100, the gas utilization rate is high, and improvement in power generation efficiency is realized. Can do.

  In addition, the gas diffusion supply member has not only gas supply but also a mechanical strength member and a separator function and can supply gas to both sides of the gas singly, so that it has excellent mechanical strength. In addition, when a fuel cell is configured by stacking in multiple stages, the stack density of the stack becomes high, and this enables a reduction in the size and output of the fuel cell. -It is extremely suitable for mounting on machines.

  Further, as a more preferred embodiment, the gas diffusion supply member can form the flow path substrate 1 with a conductive material, and a SUS-based material, Inconel, or the like can be used as a specific material.

As a result, the gas diffusion supply member also has a function as a current collector, and can realize further improvement in the stack density of the stack when the fuel cell is configured, and also a fuel such as Ni cermet. in comparison with the case of using the electrode material or La1- × an air electrode material such as Sr × MnO ₃ porous body as a current collector may be implemented well as cost reduction with excellent mechanical strength.

  Further, as a more preferred embodiment, the gas diffusion supply member can have a noble metal coating on the surface of the flow path substrate 1, and in this case, the material of the flow path substrate 1 includes a SUS-based material, Not only a conductive material such as Inconel but also an insulating material such as alumina can be used. As the noble metal, nickel, silver, platinum, or the like can be used on the fuel electrode side, and silver, platinum, or the like can be used on the air electrode side.

  Thus, by providing the noble metal coating on the surface of the flow path substrate 1, heat resistance, corrosion resistance and high conductivity can be obtained, the gas diffusion supply member can be used as a current collector, and fuel This contributes to improving battery output and ensuring safety (reliability).

  In the above embodiment, the case where the upper surface side of the flow path substrate 1 is the fuel electrode side and the lower surface side is the fuel electrode side and the reducing gas and the oxidizing gas are supplied in a diffused manner has been described. In this case, when the upper and lower power generating elements are laminated so that the same poles face each other, either one of the oxidizing gas and the reducing gas is supplied to the flow path substrate 1, and the same gas is supplied to the upper and lower same poles. The diffusion can be supplied.

  FIG. 2 is a view for explaining another embodiment of a gas diffusion supply member for a fuel cell according to the present invention. In the previous embodiment, the gas diffusion supply member shown in the figure has a plate-like porous body laminated on the flow path substrate. Gas flow ports 4 and 5 are formed, and porous bodies 6 and 7 are provided inside each gas flow port 4 and 5.

  Each gas circulation port 4 and 5 is formed in a trapezoidal cross section with the outside of the gas flow path as a long side as shown in FIG. The molded porous bodies 6 and 7 are fitted and fixed. In this case, the porous bodies 6 and 7 do not have to be bonded to the gas flow ports 4 and 5 simply by fitting, may be bonded by ceramic bonding or brazing, 5 and the porous bodies 6 and 7 are trapezoidal in cross section as described above, there is no fear that the porous bodies 6 and 7 fall into the gas flow paths 2 and 3.

  The gas diffusion supply member having the above configuration can obtain the same effect as that of the previous embodiment, and as is clear by comparing FIG. 1 (c) and FIG. 2 (c), The thickness can be reduced by the amount of the porous bodies 6 and 7, and the stack density of the stack when the fuel cell is formed by stacking in multiple stages together with the power generation element can be further increased. It can contribute to higher output.

  FIG. 3 is a view for explaining still another embodiment of a gas diffusion supply member for a fuel cell according to the present invention. The illustrated flow path substrate 1 constituting the gas diffusion supply member includes an inflow gas flow path 2 having an upward inflow gas circulation port 4 and an inflow having a downward inflow gas circulation port 4 in the vertical direction of the drawing. The gas flow path 2 is connected to the closed ends in a straight line, and has an outflow gas flow path 3 having an upward outflow gas circulation port 5 and a downward outflow gas circulation port 5. The outflow gas flow path 3 is connected linearly at the closed ends.

  Further, in the left-right direction in the figure, the open ends of the inflow gas passage 2 having the upward inflow gas circulation port 4 and the outflow gas passage 3 having the downward outflow gas circulation port 5 are adjacent to each other. In addition to the arrangement, the outflow gas passage 2 having the upward outflow gas circulation port 5 and the open end of the inflow gas passage 3 having the downward inflow gas circulation port 4 are adjacent to each other. . The flow path substrate 1 includes a porous body (not shown).

  As shown by the arrows in the figure, for example, the oxidizing gas circulates from the upper side to the lower side of the flow path substrate 1 in the gas flow paths 2 and 3 having the upward gas flow ports 4 and 5 due to the above configuration. Further, in the gas flow paths 2 and 3 having the downward gas flow ports 4 and 5, for example, as indicated by the arrows, the reducing gas flows from the lower side to the upper side in the figure.

  Here, the gas flowing through the fuel cell has a higher temperature on the outflow side than the inflow side by passing through a power generation element that generates an electrochemical reaction. Therefore, in the gas diffusion supply member, as described above, the open ends of the inflow gas channel 2 and the outflow gas channel 3 are arranged adjacent to each other, so that the inflow gas channel 2 through which the low-temperature gas flows is arranged. Heat exchange with the outflow gas flow path 3 through which the high-temperature gas circulates, thereby making the entire temperature distribution uniform.

  In the above configuration, the inflow gas passage 2 having the upward inflow gas flow port 4 and the outflow gas flow channel 3 having the downward outflow gas flow port 5 are arranged adjacent to each other, that is, The heat exchange is performed between the low-temperature reducing gas and the high-temperature oxidizing gas. However, the heat exchange is configured such that the inflow and outflow gas flow paths 2 having upward gas flow ports 4 and 5 are provided. , 3 may be arranged adjacent to each other, that is, arranged to exchange heat between the same gases.

  FIG. 4 is a view for explaining still another embodiment of a gas diffusion supply member for a fuel cell according to the present invention. That is, the gas flow paths (tubular bodies 1a) 2 and 3 of the flow path substrate 1 in the gas diffusion supply member have a trapezoidal cross section as shown in FIG. 4A in addition to the rectangular cross section described in the previous embodiment. Or a triangular cross-section as shown in FIG. 4B, a circular cross-section as shown in FIG. 4C, or other cross-sectional shapes.

  When the gas flow paths 2 and 3 have a trapezoidal cross section and a triangular cross section, the adjacent flow paths are arranged so that the shapes of the adjacent flow paths are upside down. The effective area can be increased, and in particular, the gas supply to the power generation element can be made more sufficient by the inflow gas circulation port 4 to contribute to further improvement in power generation efficiency.

  In addition, when the gas flow paths 2 and 3 are circular in cross section, they have higher durability against stress such as thermal expansion, and can further improve the mechanical strength. By forming the use gas flow port 4 and the outflow gas flow port 5 in directions opposite to each other, the residence time of the gas between the flow path substrate 1 and the power generation element can be further increased, and the power generation efficiency can be further increased. Can contribute to improvement.

  FIG. 5 is a view for explaining still another embodiment of a gas diffusion supply member for a fuel cell according to the present invention. In the gas diffusion supply member shown in the previous embodiment, the same number of gas flow ports are provided in all the gas flow paths, whereas the inflow gas flow paths 2 have a plurality of predetermined intervals in the longitudinal direction. The inflow gas passage 3 that has an inflow gas flow port 4 and that forms a pair with the inflow gas flow channel 2 flows out from the two adjacent inflow gas flow ports 4 at a substantially equal distance. It has a working gas distribution port 5.

  That is, when two inflow gas flow ports 4 are formed in the inflow gas channel 2 as shown in the figure, the outflow gas flow channel 3 corresponds to the center of the two inflow gas flow ports 4. One outflow gas circulation port 5 is formed at a position where the gas flows. Therefore, when many inflow gas circulation ports 4 are formed in the inflow gas passage 2, the outflow gas passage 3 is formed with one fewer outflow gas circulation ports 5. Therefore, the gas circulation ports 4 and 5 are arranged in a staggered manner with respect to the inflow gas passage 2 and the outflow gas passage 3.

  In the gas diffusion supply member described above, in the flow path substrate 1, the gas is retained between the flow path substrate 1 and the power generation element by making the distance from the inflow gas flow port 4 to the outflow gas flow port 5 as long as possible. The generation of a region where gas does not flow can be eliminated by extending the time, which can contribute to further improvement in power generation efficiency.

  FIG. 6 is a view for explaining still another embodiment of a gas diffusion supply member for a fuel cell according to the present invention. The illustrated gas diffusion supply member includes a partition plate 8 in which an inflow gas channel 2 of a channel substrate 1 extends in a longitudinal direction from an open end. The partition plate 8 has an open end of the inflow gas passage 2 at a closed portion 9a on the gas flow port side (upper side in the drawing) and an open portion 9b on the anti-gas flow port side (lower side in the drawing). It is partitioned.

  In the gas diffusion supply member described above, when gas is supplied to the open portion 9b of the inflow gas flow path 2, the gas restricted by the partition plate 8 passes through the intermediate portion of the inflow gas flow path 2 for each inflow. Since the gas flows toward the gas flow port 4, the gas can be uniformly discharged from each inflow gas flow port 4, whereby the gas can be more uniformly diffused and supplied to the electrode. This can contribute to further improvement in power generation efficiency.

Example 1
As the cylinder forming the gas flow path, a square pipe made of SUS430 having a square shape with a cross section of 5 mm inside and 6 mm outside and 72 mm in length was used. In this embodiment, twelve cylinders were prepared, and each cylinder was fixed to the end of one side by welding a member of the same material as that of the cylinder, with one end being an open end and the other being a closed end. In addition, on each surface of each cylinder, a 4 mm × 4 mm gas circulation port with each position as an end was formed at a position of 8 mm, 28 mm, and 48 mm from the open end.

  Next, based on the arrangement shown in FIGS. 1A and 1B, twelve cylinders are connected by welding to form a flow path substrate. As shown in FIG. A flat porous body made of foamed nickel (length 70 mm × width 70 mm × thickness 100 μm) is laminated on the surface on the fuel electrode side, and the surface on the air electrode side of the flow path substrate is made of foamed silver. A plate-like porous body (length 70 mm × width 70 mm × thickness 100 μm) was laminated to prepare a gas diffusion supply member.

  Further, a power generation element composed of an electrolyte layer made of YSZ, an air electrode layer made of LSC, and a fuel electrode layer made of NiO-YSZ was created, and this power generation element was sandwiched between two gas diffusion supply members, and FIG. The fuel cell shown in c) was prepared.

  As a comparative example, a gas diffusion supply member having the same configuration as that of the above example except that both ends of the gas flow path are open ends is created, and a similar fuel cell is created together with a power generation element. A power generation experiment of the battery and the fuel cell of Example 1 was performed.

  As a result, in the fuel cell of Example 1, it was found that the reduction time of the fuel electrode was about half that of the comparative example, and that a higher fuel utilization rate was obtained at a take-out voltage of 0.7 V after fuel reduction. That is, in the comparative example, since both ends of the gas flow path are open ends, the gas supply to the electrode is insufficient, whereas the gas diffusion supply member of Example 1 supplies the gas to the electrode. It was confirmed that the power generation efficiency of the fuel cell can be improved.

(Example 2)
A flow path substrate shown in FIGS. 2A and 2B was formed in the same manner as in Example 1 except that there was one gas circulation port in the cylinder and the size was 4 mm × 56 mm. At this time, the gas circulation port had a trapezoidal cross section as shown in the enlarged view of FIG. A porous body made of foam metal is fitted into the gas flow port on the fuel electrode side of the flow path substrate and fixed by brazing, and the cermet is connected to the gas flow port on the air electrode side of the flow path substrate. A porous body composed of the above was fitted and fixed with a ceramic bond to prepare a gas diffusion supply member. Thereafter, a power generation element similar to that in Example 1 was sandwiched between two gas diffusion supply members, and a fuel cell shown in FIG.

  Even in the fuel cell of Example 2, the same effect as that of Example 1 can be obtained, and in particular, since the porous body is not laminated, gas sealing when creating the fuel cell is easy. It was confirmed that the contact resistance could be reduced.

(Example 3)
The inflow gas flow channel is formed with 4 mm × 4 mm inflow gas flow ports with the respective ends as 8 mm and 48 mm from the open end, and the outflow gas flow channel from the open end. The flow path substrate shown in FIG. 5 was formed in the same manner as in Example 1 except that a 4 mm × 4 mm outflow gas circulation port having the end at the position was formed at a position of 28 mm. Then, a planar porous body similar to that in Example 1 is laminated on both surfaces of the flow path substrate to form a gas diffusion supply member, and then a power generation element is sandwiched between the two gas diffusion supply members to produce a fuel cell. did.

  In the fuel cell of Example 3, it was found that the fuel utilization rate was 1.05 times at the extraction voltage of 0.7 V compared to Example 1, and the position of the gas circulation port was devised as described above. As a result, it was confirmed that the residence time of the gas between the power generation element and the gas diffusion supply member becomes longer and the utilization rate of the gas is further increased.

Example 4
Example 1 was performed except that the partition plate shown in FIG. 6 was provided inside the inflow gas passage. That is, a member made of the same material as the cylinder is fixed to both ends of the cylinder forming the inflow gas flow path by welding, and then a hole of 1.9 mm in length × 4 mm in width is drilled in one half of one member Was formed as an open portion, and the remaining half on one side was defined as a closed portion. Then, a cut was formed between the open part and the closed part at the end of the cylinder, and a partition plate (vertical 25 mm × width 5 mm × thickness 0.2 mm) was fitted into this cut and fixed by welding. Then, a planar porous body similar to that in Example 1 is laminated on both surfaces of the flow path substrate to form a gas diffusion supply member, and then a power generation element is sandwiched between the two gas diffusion supply members to produce a fuel cell. did.

  In the fuel cell of Example 4, it was found that the temperature distribution of the power generation element was more uniform than that of Example 1, and the fuel utilization rate was 1.06 times at the extraction voltage of 0.7 V. Then, it was confirmed that the gas supply from the three gas circulation ports formed in the inflow gas flow path becomes more uniform.

It is the perspective view (a) which shows an example of the flow-path board | substrate in the gas diffusion supply member of this invention, sectional drawing (b) of a gas diffusion supply member, and sectional drawing (c) of a fuel cell. It is the perspective view (a) which shows the other example of the flow-path board | substrate in the gas diffusion supply member of this invention, sectional drawing (b) of a gas diffusion supply member, and sectional drawing (c) of a fuel cell. It is a top view which shows the other example of the flow-path board | substrate in the gas diffusion supply member of this invention. It is a perspective view which shows three examples from which the cross-sectional shape of a gas flow path differs as another example of the flow-path board | substrate in the gas diffusion supply member of this invention. It is the perspective view (a) and top view (b) which show the other example of the flow-path board | substrate in the gas diffusion supply member of this invention. As another example of the flow path substrate in the gas diffusion supply member of the present invention, there are a perspective view (a) and a cross-sectional view (b) showing some inflow gas flow paths.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flow path board | substrate 1a Cylindrical body 2 Inflow gas flow path 3 Outflow gas flow path 4 Inflow gas distribution port 5 Outflow gas distribution port 6 Porous body by the side of a fuel electrode 7 Porous body by the side of an air electrode 8 Partition plate 9a Open part 9b Closed part 100 Power generation element 101 Electrolyte layer 102 Air electrode layer 103 Fuel electrode layer

Claims (11)

  A flow channel substrate that is a member that diffusely supplies an oxidizing gas or a reducing gas so as to face a power generation element of a fuel cell, and includes a plurality of gas flow channels having one end as an open end and the other end as a closed end. In addition, a plurality of gas flow paths are provided in a number corresponding to at least two sets, one for inflow and one for outflow, and open to one side of the flow path substrate in some sets of gas flow paths. In addition to providing a gas flow port, a gas flow port that opens on the other surface of the flow path substrate was provided in the remaining set of gas flow paths, and a porous body that allowed gas to pass between the gas flow path and the power generation element was provided. A gas diffusion supply member for a fuel cell.   The gas diffusion supply member for a fuel cell according to claim 1, wherein a porous body is provided inside the gas flow port.   3. The fuel according to claim 1, wherein the gas flow path is formed by a cylindrical body closed on one side, and the flow path substrate is formed by integrating a plurality of cylindrical bodies. Gas diffusion supply member for battery.   A gas flow path having a gas flow opening opened on one surface of the flow path substrate and a gas flow path having a gas flow opening opened on the other surface of the flow path substrate are alternately arranged. The gas diffusion supply member for a fuel cell according to any one of Items 1 to 3.   The gas diffusion supply member for a fuel cell according to any one of claims 1 to 4, wherein the open ends of the inflow gas channel and the outflow gas channel are arranged adjacent to each other.   The gas diffusion supply member for a fuel cell according to any one of claims 1 to 5, wherein the gas flow path has a cross-sectional shape of any one of a trapezoid, a triangle, and a circle.   The inflow gas flow path has a plurality of inflow gas flow ports at predetermined intervals in the longitudinal direction, and the outflow gas flow path forming a pair with the inflow gas flow path has two adjacent inflow The gas diffusion supply member for a fuel cell according to any one of claims 1 to 6, further comprising an outflow gas distribution port at a position approximately equidistant from the gas distribution port for use.   The inflow gas flow path includes a partition plate extending from the open end in the longitudinal direction and partitioning the open end into a closed portion on the gas flow port side and an open portion on the anti-gas flow port side. The gas diffusion supply member for a fuel cell according to any one of claims 1 to 7.   The gas diffusion supply member for a fuel cell according to any one of claims 1 to 8, wherein the flow path substrate is formed of a conductive material.   The gas diffusion supply member for a fuel cell according to any one of claims 1 to 9, wherein the flow path substrate has a noble metal coating on the surface.   11. A fuel cell comprising the gas diffusion supply member according to claim 1 and a power generation element formed by sandwiching an electrolyte layer between an air electrode layer and a fuel electrode layer.

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