JP2019175595A - Solid oxide fuel cell and flow rate adjusting member - Google Patents

Abstract

To provide a solid oxide fuel cell and a flow rate adjusting member, capable of setting a distribution amount of a flow amount of an air electrode gas and a fuel gas, which are supplied to each single cell via a separator of each layer with a simple structure.SOLUTION: At least one of an air electrode gas and a fuel gas G2 is supplied to an air flowing part provided to a plurality of separator via an inner manifold 2a structured so that a fuel cell battery single sell unit 3 containing a plurality of fuel battery single cells and air holes 7 and 9 penetrating a plurality of separators 4 are communicated. A solid oxide fuel cell 1 further includes a flowing amount adjustment member 6 distributed in the inner manifold, and having a partition surface 6c dividing between the inner manifold and the air flowing part. The flowing amount adjustment member includes a plurality of openings 60 which can flow a gas in the inner manifold to each of the air flowing part in the separation surface. An opening area of at least one part of the plurality of openings is different each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a solid oxide fuel cell and a flow rate adjusting member, and more particularly, to an internal manifold type solid oxide fuel cell and a solid oxide fuel cell assembled using members such as a single cell and a separator. The present invention relates to a flow rate adjusting member disposed in an internal manifold.

  A flat-plate solid oxide fuel cell (SOFC) has a single cell as a basic constituent element in which a fuel electrode (anode) and an air electrode (cathode) are bonded to both surfaces of a solid electrolyte layer. In SOFC, a power generation device is often formed by forming a stack structure in which a plurality of single cells are electrically connected in series via a separator.

  In this type of SOFC in which a plurality of separators and single cells are stacked, an air electrode gas is supplied to the air electrode and a fuel gas is supplied to the fuel electrode. A manifold structure is generally used.

  At the time of SOFC power generation, the air electrode gas supplied to the air electrode and the fuel gas supplied to the fuel electrode are consumed by reacting sequentially in the flow path, but the oxygen in the gas becomes closer to the outlet side of the flow path. Also, since the hydrogen partial pressure is reduced, the amount of gas that can be used for the electrode reaction is reduced. In addition, when the flow path is branched, the flow rate is likely to vary due to the pressure loss that is different for each flow path. At this time, since the single cell tends to generate a larger amount of heat as the power generation amount increases, the temperature distribution tends to occur for each single cell in the stack due to variations in the power generation state of each single cell.

  The SOFC is preferably operated in a predetermined temperature range. However, during the operation of the SOFC, the temperature of the central portion in the stacking direction of the SOFC is higher than the temperature of the end portion, so that the SOFC can continue power generation normally. The temperature range may be exceeded. Thus, as a response to the phenomenon that SOFC generates heat partially in the laminated structure, the cross-sectional area of the gas flow path provided in the central separator disposed in the vicinity of the central part in the SOFC laminating direction is For example, Patent Document 1 discloses a structure wider than the cross-sectional area of the gas flow path provided in the end separator disposed in the vicinity of the end in the direction. In this way, if there is a difference in the cross-sectional area of the gas flow path of the separator in each part in the stacking direction of the SOFC, the distribution amount of the flow rate of the air electrode gas and the fuel gas supplied to each single cell through the separator of each layer Can be changed in each layer.

JP 2012-209068 A

  However, if there is a difference in the cross-sectional area of the gas flow path of the separator in each part in the stacking direction of the SOFC, separators having different cross-sectional areas of the gas flow path are manufactured according to the arrangement locations in the stacking direction of the SOFC, There is a need to. In addition, there is a limit to reducing manufacturing tolerances when manufacturing separators, and it is difficult to manufacture separators with different gas flow path cross-sectional areas so that they have gas flow paths as designed, and to accurately stack them. In many cases. Therefore, it is desired to manufacture an SOFC that has a simple structure that is not easily affected by manufacturing tolerances and that can set the distribution amount of the flow rate of the air electrode gas and the fuel gas supplied to each single cell through the separator of each layer.

  The problem to be solved by the present invention is a solid oxide fuel cell capable of setting the distribution amount of the flow rate of the air electrode gas and the fuel gas supplied to each single cell through the separator of each layer and the flow rate control with a simple structure It is to provide a member.

  In order to solve the above-described problems, a solid oxide fuel cell according to the present invention includes a plurality of fuel cell single cells provided with an air electrode and a fuel electrode on both surfaces of a solid oxide electrolyte, and oxygen introduced into the air electrode. A solid oxide form having a cell stack in which a plurality of plate-like separators having gas flow portions as flow paths capable of flowing an air electrode gas containing gas and a fuel gas introduced into the fuel electrode are alternately laminated In the fuel cell, at least one of the air electrode gas and the fuel gas is configured such that a fuel cell single cell unit including the plurality of fuel cell single cells and a vent hole penetrating the plurality of separators communicate with each other. The solid oxide fuel cell is further supplied to the gas circulation part provided in each of the plurality of separators via an internal manifold. A flow rate adjusting member that is disposed in the hold and has a partition surface that partitions the internal manifold and the gas flow part, and the flow rate adjusting member causes the gas in the internal manifold to flow into the partition surface. It has a plurality of openings that can be circulated in each of the gas circulation portions, and at least some of the opening areas of the plurality of openings are different from each other.

  In addition, at least some of the plurality of separators may have the same shape and arrangement of the gas circulation part.

  Further, the flow rate adjusting member is a cylindrical body having a hollow portion through which gas supplied to the internal manifold flows, and is inserted into the internal manifold, and the partition surface provided with the opening is It is an outer wall of the said cylindrical body facing a gas distribution part, and the gas supplied to the said internal manifold is good to distribute | circulate through the said hollow part, and flows out into the said gas distribution part.

  The flow rate adjusting member may be inserted into the internal manifold and fixed to the single fuel cell and the separator.

  The flow rate adjusting member may be disposed in the internal manifold through which the fuel gas introduced into the fuel electrode flows.

  Further, the flow rate adjusting member has a plurality of openings in the partition surface, and has a central portion along a direction in which the plurality of single fuel cell cells and the plurality of separators are alternately stacked. The opening area of the opening may be provided wider than the opening area of the opening at the end.

  In addition, in at least some of the plurality of openings, a dimension in a direction in which the plurality of single fuel cell units and the plurality of separators are alternately stacked is along a direction intersecting the direction. It is good to have a distribution.

  The solid oxide fuel cell has a plurality of the cell stacks, and the sum of the opening areas of the flow rate adjusting members disposed in the internal manifold of each cell stack is different from each other. It is good to be.

  Here, a plurality of fuel cell single cells provided with an air electrode and a fuel electrode on both surfaces of the solid oxide electrolyte, an air electrode gas containing oxygen introduced into the air electrode, and a fuel gas introduced into the fuel electrode, respectively A flow rate adjusting member provided in a solid oxide fuel cell in which a plurality of plate-shaped separators having gas flow portions as flow paths capable of flowing are alternately stacked, wherein the flow rate adjusting member is the plurality of fuel cells. A fuel cell single cell unit including a single cell and an internal manifold configured to communicate with a vent hole penetrating the plurality of separators, and a partition surface that partitions the internal manifold and the gas circulation portion And having a plurality of openings provided at positions corresponding to the respective gas circulation portions on the partition surface, and at least a part of the opening area of the plurality of openings is The gist that you have each other different.

  In addition, the opening area of the opening at the center with respect to the longitudinal direction of the partition surface may be larger than the opening area of the opening at the end with respect to the longitudinal direction of the partition surface.

  In addition, in at least some of the plurality of openings, the dimension of the partition surface in the longitudinal direction may have a distribution along a direction intersecting the direction.

  The solid oxide fuel cell according to the present invention includes a flow rate adjusting member provided in the internal manifold and provided with a partition surface that partitions the internal manifold and the gas flow part. The surface has a plurality of openings through which the gas in the internal manifold can flow to each of the gas flow portions, and at least some of the opening areas of the plurality of openings are different from each other. Therefore, the flow rate of the air electrode gas or fuel gas supplied to each single cell through each separator is defined by the opening area of the opening provided in the partition surface of the flow rate adjusting member, and the plurality of fuel cell single cells and the plurality of separators Are different from each other in the layers along the direction in which the layers are alternately stacked.

  Thus, by adjusting the opening area of the opening provided on the partition surface of the flow rate adjusting member according to the position of the corresponding separator, the distribution amount of the gas supplied to each single cell via each separator can be freely set. Can be set. As a result, the amount of gas that can be used for power generation, and the fuel utilization rate and air utilization rate due to gas contact with each single cell during power generation are controlled according to the position in the laminated structure, and each unit is controlled. The state of the cell during power generation can be controlled. As a result, for example, it is possible to suppress variation in state during power generation between single cells, or to intentionally provide a distribution in the power generation state between single cells. Thereby, the power generation distribution of the solid oxide fuel cell can be made uniform, and the power generation efficiency of the solid oxide fuel cell can be improved.

  Moreover, since the flow rate of the gas supplied to each separator can be adjusted simply by adjusting the opening area of the opening provided on the partition surface of the flow rate adjusting member, for the purpose of adjusting the gas flow rate, Eliminates the need for precise design and manufacture. Moreover, it is not necessary to manufacture a large number of separators having different shapes and arrangements of the gas flow portions. Therefore, the configuration of the solid oxide fuel cell can be simplified.

  Further, when at least a part of the plurality of separators has the same shape and arrangement of the gas circulation part, the partition surface of the flow rate adjusting member also in the plurality of separators having the same shape and arrangement of the gas circulation part By adjusting the opening area of the opening provided in the gas flow rate, the gas flow rate can be made different between the layers. Moreover, it is not necessary to manufacture a plurality of types of separators having different shapes and arrangements of the gas flow parts, and the manufacturing cost of the solid oxide fuel cell can be suppressed.

  The flow rate adjusting member is a cylindrical body having a hollow portion through which the gas supplied to the internal manifold flows, and the partition surface provided with the opening is opposed to the gas flow portion. When the gas supplied to the internal manifold flows through the hollow portion and flows out from the opening to the gas circulation portion, an opening having a desired opening area is formed on the outer wall of the tubular member. The flow rate adjusting member can be formed with a simple configuration that only forms Further, the internal space of the flow rate adjusting member can be obtained simply by disposing the cylindrical flow rate adjusting member in the cylindrical internal space of the internal manifold formed by communicating the vent holes provided in each separator and each fuel cell single cell. It is possible to supply a gas having a flow rate corresponding to the opening area of each opening to the gas circulation portion of each separator while ensuring airtightness between the opening and the internal manifold. Further, when assembling a laminated structure composed of a fuel cell single cell and a separator, the single cell and the separator are arranged one layer at a time in order by inserting a cylindrical flow rate adjusting member through each vent hole, Positioning between the separators and positioning between the single cell / separator stacked structure and the flow rate adjusting member can be easily achieved.

  Further, when the flow rate adjusting member is inserted into the internal manifold and fixed to the fuel cell unit cell and the separator, the structure of the solid oxide fuel cell including the flow rate adjusting member is strengthened. be able to. Moreover, the distribution amount of the gas supplied to each fuel cell single cell via each separator can be maintained as designed over a long period of time. Therefore, the present invention can be particularly suitably applied to applications in which a distribution is constantly formed in the distribution amount of gas for the purpose of suppressing variations in the power generation state that does not change with time.

  Further, when the flow rate adjusting member is disposed in the internal manifold through which the fuel gas introduced into the fuel electrode flows, by setting the distribution amount of the flow rate of the fuel gas introduced into the fuel electrode, the fuel electrode is set. By controlling the state of the electrode reaction in, it is possible to control the power generation state in the SOFC single cell of each layer along the direction in which the plurality of fuel cell single cells and the plurality of separators are alternately stacked. Therefore, it is possible to improve the utilization rate of the fuel gas and suppress the inflation of heat generation. Thereby, deterioration of a fuel cell single cell can be suppressed.

  Further, the flow rate adjusting member has a plurality of openings in the partition surface, and the opening area of the opening in the central portion along the direction in which the plurality of fuel cell single cells and the plurality of separators are alternately stacked. However, when the opening area of the opening at the end portion is wide, the distribution amount of the gas flow supplied to the center portion of the stacked structure is divided into the distribution of the flow rate of the gas supplied to the end portion of the stacked structure. It can be increased compared to the amount.

  Compared with the end layer, the layer at the center in the stacking direction of the solid oxide fuel cell tends to generate heat due to the power generation state inside the layer. Therefore, by increasing the distribution amount of the gas flow rate supplied to the central portion of the stacked structure as compared with the distribution amount of the gas flow rate supplied to the end portion of the stacked structure, the layer at the central portion of the stacked structure is reduced. Compared with the part layer, the fuel utilization rate and the air utilization rate can be lowered, the load due to high temperature can be reduced, and the power generation distribution of the solid oxide fuel cell can be made uniform. As a result, the power generation efficiency of the solid oxide fuel cell can be improved.

  In addition, in at least some of the plurality of openings, the dimension in the direction in which the plurality of fuel cell single cells and the plurality of separators are alternately stacked is distributed along the direction intersecting the direction. If it is provided, the amount of gas to be supplied can be adjusted for each location in one fuel cell unit cell in each layer along the stacking direction of the solid oxide fuel cell. Thereby, the state at the time of the electric power generation for every place in each single cell can be controlled. As a result, for example, it is possible to suppress variations in state during power generation for each location in the single cell, and to intentionally provide a distribution in the power generation status for each location in the single cell. Thereby, the power generation distribution for each place in the single cell can be made uniform, and the power generation efficiency of the single cell can be improved.

  Further, when the solid oxide fuel cell has a plurality of cell stacks and the sum of the opening areas of the flow rate adjusting members disposed in the internal manifold of each cell stack is different from each other. The total amount of gas to be supplied can be adjusted for each cell stack. For example, a flow control member with a small sum of opening areas is arranged in a cell stack in which gas easily circulates, and a flow control member with a large sum of opening areas is arranged in a cell stack in which gas is difficult to circulate. Can be set. As a result, when a power generation module is configured with a large number of cell stacks, the mutual arrangement of a plurality of cell stacks, the positional relationship with other devices, the configuration of a supply path for supplying gas to the large number of cell stacks, etc. Differences in the power generation state and the amount of heat generated between the cell stacks that may be caused can be mitigated.

  Here, the flow rate adjusting member of the solid oxide fuel cell according to the present invention has a partition surface that partitions between the internal manifold of the SOFC and the gas circulation part, and the partition surface corresponds to each gas circulation part. It has the some opening provided in the position, The opening area of at least one part among several opening differs mutually. Therefore, when disposed in the internal manifold of the solid oxide fuel cell, the flow rate of the air electrode gas or the fuel gas supplied to each single cell through the separator of each layer is defined by the opening area of the opening. . Thus, by adjusting the opening area of the opening provided on the partition surface of the flow rate adjusting member according to the position of the corresponding separator, the distribution amount of the gas supplied to each single cell via each separator can be freely set. Can be set. As a result, the amount of cathode gas and / or fuel gas that can be used for power generation, as well as the fuel utilization rate and air utilization rate due to gas contact with each single cell during power generation, are positioned in the laminated structure. The power generation distribution of the solid oxide fuel cell can be made uniform by controlling accordingly and controlling the power generation state of each single cell. As a result, the power generation efficiency of the solid oxide fuel cell can be improved. Moreover, in order to adjust the gas distribution amount in the laminated structure, by using a member arranged in the internal manifold, the adjustment of the gas distribution amount can be achieved more easily than in the case of designing the flow rate of the separator.

  In addition, when the opening area of the central opening with respect to the longitudinal direction of the partition surface is wider than the opening area of the end opening with respect to the longitudinal direction of the partition surface, the length of the partition surface The distribution amount of the gas supplied to the central portion with respect to the direction can be increased as compared with the distribution amount of the gas supplied to the end portion with respect to the longitudinal direction of the partition surface. Therefore, by disposing the flow rate adjusting member in the internal manifold, the fuel utilization rate and air utilization rate are reduced in the central layer of the laminated structure compared to the end layer, and the load due to high temperatures is reduced. The power generation distribution of the solid oxide fuel cell can be made uniform. In addition, when the low-temperature gas comes into contact with the fuel cell single cell during power generation, the central layer of the laminated structure can be cooled more than the end layer. As a result, the power generation efficiency of the solid oxide fuel cell can be improved.

  Further, in at least some of the plurality of openings, when the dimension in the direction with respect to the longitudinal direction of the partition surface is distributed along the direction intersecting the direction, the longitudinal direction of the partition surface In each opening along the line, the amount of gas to be supplied can be adjusted for each place in one fuel cell single cell. Thereby, the state at the time of the electric power generation for every place in each single cell can be controlled. As a result, for example, it is possible to suppress variations in state during power generation for each location in the single cell, and to intentionally provide a distribution in the power generation status for each location in the single cell. Thereby, the power generation distribution for each place in the single cell can be made uniform, and the power generation efficiency of the single cell can be improved.

It is a schematic diagram which shows the cross section of the solid oxide fuel cell concerning one Embodiment of this invention. It is a disassembled perspective view which shows the fuel cell single cell and separator which comprise the said solid oxide fuel cell. It is a perspective view which shows the flow volume adjustment member of the solid oxide fuel cell concerning one Embodiment of this invention.

  Hereinafter, a solid oxide fuel cell (SOFC) according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing a cross section of an SOFC according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing the SOFC single cell and the separator constituting the SOFC of FIG.

[Outline of solid oxide fuel cell]
As shown in FIG. 1, a cell stack 1 constituting an SOFC according to an embodiment of the present invention includes a plurality of separators 4 and a plurality of SOFC single cell units 3 that are a plurality of fuel cell single cell units alternately stacked. A plurality of SOFC single cell units 3 are stacked in series and electrically connected via a separator 4. Further, the cell stack 1 is placed on the grounding portion 1b, and a cover 1c is provided on the upper surface of the uppermost separator 4.

  The cell stack 1 is provided with supply paths 2a and 2b configured as internal manifolds, and a flow rate adjusting member 6 is inserted into the supply path 2a. Here, the flow rate adjusting member 6 is a member for setting a distribution amount of the flow rate of the fuel gas G2 supplied to each single cell 30 which is each single fuel cell cell via the separator 4 of each layer. The flow rate adjusting member 6 will be described in detail later.

  The SOFC single cell unit 3 includes a single cell 30 and an insulating frame 50 as shown in FIG. The single cell 30 has a flat electrolyte layer 31 made of a solid oxide electrolyte, an air electrode 32 joined to one surface of the electrolyte layer 31, and a fuel electrode 33 joined to the other surface. Here, the material constituting the electrolyte layer 31 and the electrodes 32 and 33 may be appropriately selected from materials used in known SOFCs.

  The insulating frame 50 is made of an insulator having heat resistance that can withstand use at the operating temperature of the SOFC. The insulating frame 50 is disposed between the plurality of separators 4 in a state in which the single cells 30 are accommodated so as to surround the side surfaces of the single cells 30, and while ensuring insulation between the plurality of separators 4, the plurality of separators 4. It plays a role in defining the interval. The insulating frame 50 isolates the fuel gas G2 flowing through the fuel gas passage 71 of the separator 4 (described later) and the air electrode gas G1 flowing through the air passage 81 from each other in a state where no mutual mixing occurs. Is done. The insulating frame 50 is provided with a pair of air passage holes 10 and fuel gas passage holes 9 as through holes.

  The separator 4 is a flat plate member made of a metal material having heat resistance such as stainless steel. The separator 4 is integrally provided with a frame portion 4a on the outer peripheral portion, and an air electrode gas G1 such as air containing oxygen introduced into the air electrode 32, and a fuel gas G2 such as hydrogen and methane introduced into the fuel electrode 33, respectively. An air passage hole 8 and a fuel gas passage hole 7 that are independently vents are provided in the frame portion 4a. The air passage hole 8 and the fuel gas passage hole 7 are provided through the surface of the frame portion 4 a of the separator 4.

  In the separator 4, a plurality of grooves running in parallel as flow paths through which the fuel gas G <b> 2 can flow are provided in the inner region surrounded by the upper surface of the frame portion 4 a, and function as the fuel gas flow path 71. . In addition, a plurality of grooves running in parallel as flow paths through which the air electrode gas G <b> 1 can flow are provided in an inner region surrounded by the lower surface of the frame portion 4 a, and function as the air flow path 81. The fuel gas flow path 71 and the air flow path 81 constitute a gas flow part of the separator 4. The air flow path 81 is provided in a direction orthogonal to the fuel gas flow path 71. Further, the fuel gas flow channel 71 communicates with the fuel gas passage hole 7, and the air flow channel 81 communicates with the air passage hole 8. The air passage hole 8 and the fuel gas passage hole 7 correspond to the air passage hole 10 and the fuel gas passage hole 9 provided in the insulating frame 50, that is, when the separator 4 and the SOFC single cell unit 3 are stacked. Further, the air passage hole 8 of the separator 4 and the air passage hole 10 of the insulating frame 50 overlap each other, and the fuel gas passage hole 7 of the separator 4 and the fuel gas passage hole 9 of the insulating frame 50 overlap each other. The position and shape are set.

  All the separators 4 constituting the cell stack 1 have the same outer shape in design, and are provided so that the shape and arrangement of the air flow path 81 through which the air electrode gas G1 flows are the same. Further, the fuel gas channel 71 through which the fuel gas G2 flows is provided in the same shape and arrangement. That is, they have the same design shape. All the single cells 30 are also designed to have the same structure. In the present embodiment, all the separators 4 have the same design shape. However, the design shapes of all the separators 4 are not necessarily the same, and a plurality of separators 4 may be used depending on the design purpose of the cell stack 1. As long as at least some of the separators 4 have the same design shape.

  As shown in FIGS. 1 and 2, in the cell stack 1, a plurality of separators 4 and a plurality of SOFC single cell units 3 are alternately stacked along the stacking direction X. The separator 4 is disposed such that the fuel gas flow path 71 faces the fuel electrode 33 of the single cell 30 and the air flow path 81 faces the air electrode 32 of the single cell 30. The separator 4 and the SOFC single cell unit 3 are airtightly joined by a heat-resistant adhesive and formed as an integral structure. Also in the cell stack 1, the path through which the fuel gas G2 flows and the path through which the air electrode gas G1 flows are isolated from each other using a heat-resistant adhesive.

  In the cell stack 1, the fuel gas passage hole 7 provided in each separator 4 and the fuel gas passage hole 9 provided in each SOFC single cell unit 3 communicate linearly, and a cylindrical internal space is formed. The supply paths 2a and 2b are configured. The supply paths 2a and 2b are opposed to each other with the fuel gas flow path 71 of each separator 4 interposed therebetween, and have two parallel paths, which respectively function as a forward path and a return path for the fuel gas G2. The supply path 2a and the supply path 2b communicate with the fuel gas flow path 71 at one end and the other end of each separator 4, respectively, and pass through the fuel gas flow path 71 of each separator 4 from the supply path 2a to the supply path 2b. A path for the fuel gas G2 is formed. Similarly, an air passage hole 8 provided in each separator 4 and an air passage hole 10 provided in each SOFC single cell unit 3 communicate linearly, and supply passages 1a having a cylindrical inner space, 1b is constituted. The supply paths 1a and 1b have two parallel paths facing each other across the air flow path 81 of each separator 4, and function as the forward path and the return path of the air electrode gas G1, respectively. The supply path 1a and the supply path 1b communicate with the air flow path 81 at one end and the other end of each separator 4, respectively, and reach the supply path 1b from the supply path 1a through the air flow path 81 of each separator 4. A path for the air electrode gas G1 is formed.

  Here, the paths of the fuel gas G2 and the air electrode gas G1 in the cell stack 1 will be specifically described. In the cell stack 1, the flow rate adjusting member 6 is disposed in the internal space of the supply path 2a, and the fuel gas G2 is introduced through the flow rate adjusting member 6. First, the flow rate adjusting member 6 is omitted and the fuel gas G2 is omitted. Will be described.

  The fuel gas G2 is introduced into the supply path 2a in which the fuel gas passage hole 7 of the separator 4 and the fuel gas passage hole 9 of the insulating frame 50 are continuous, as indicated by the solid arrow in FIG. Further, the air electrode gas G1 is introduced into the supply path 1a in which the air passage hole 8 of the separator 4 and the air passage hole 10 which is the ventilation hole of the insulating frame 50 are continuous as shown by the dotted arrow in FIG. The

  As shown by an arrow A in FIG. 1, the fuel gas G2 flows through the supply path 2a and is introduced into the fuel gas flow path 71 of each separator 4 communicating with the supply path 2a. Then, the fuel gas G <b> 2 contacts the fuel electrode 33 of the single cell 30 while flowing through the fuel gas channel 71 of each separator 4. The fuel gas G2 flowing through the fuel gas flow path 71 of each separator 4 joins in the supply path 2b, and is guided to the outside of the cell stack 1 through the supply path 2b as indicated by an arrow B. Although not shown, the air electrode gas G1 is also introduced into the air flow path 81 of each separator 4 communicating with the supply path 1a through the supply path 1a. The air electrode gas G <b> 1 contacts the SOFC air electrode 32 while flowing through the air flow path 81 of each separator 4. The air electrode gas G1 flowing through the air flow path 81 of each separator 4 joins in the supply path 1b and is guided to the outside of the cell stack 1.

  As described above, the air electrode gas G1 and the fuel gas G2 flow through the supply paths 1a and 2a, and further branch into the air flow path 81 and the fuel gas flow path 71 of each separator 4 communicating with the supply paths 1a and 2a. As a result, the air is supplied to the air electrode 32 and the fuel electrode 33 of the single cell 30 of each SOFC single cell unit 3. The single cell 30 uses the air electrode gas G1 supplied to the air electrode 32 through the air flow path 81 and the fuel gas G2 supplied to the fuel electrode 33 through the fuel gas flow path 71. Electrode reaction is caused in each of the air electrode 32 and the fuel electrode 33 to generate power.

  Here, as described above, in the actual cell stack 1, the flow rate adjusting member 6 described in detail below is disposed in the supply path 2a through which the fuel gas G2 flows, and is supplied to the cell stack 1. The fuel gas G2 is not directly introduced into the internal space of the supply passage 2a, but is introduced into the fuel gas passage 71 via the flow rate adjusting member 6 and supplied to the fuel electrode 33. In the present embodiment, the same flow rate adjusting member is not disposed in the supply path 1a for introducing the air electrode gas G1, and the air electrode gas G1 supplied into the cell stack 1 is shown in FIG. The gas flows directly through the supply path 1 a, is introduced into the air flow path 81, and is supplied to the air electrode 32.

[Flow control member]
Next, the flow rate adjusting member 6 according to an embodiment of the present invention disposed in the cell stack 1 will be described with reference to the drawings. FIG. 3 is a perspective view showing a flow rate adjusting member according to an embodiment of the present invention.

  The flow rate adjusting member 6 is arranged in the internal space of the supply path 2a for introducing the fuel gas G2 in the cell stack 1, and in the direction X in which a plurality of SOFC single cell units 3 and a plurality of separators 4 are alternately stacked. It is a member that can regulate the flow rate of the fuel gas G <b> 2 supplied to the fuel electrode 33 of the single cell 30 via the separator 4 in each of the layers along.

  As shown in FIG. 3, the flow rate adjusting member 6 is a rectangular tube-shaped member having a hollow portion 6b. The flow rate adjusting member 6 is formed so that the cross section perpendicular to the longitudinal direction of the outer rectangular tube shape is a substantially rectangular shape that is slightly smaller than the cross section intersecting the X direction of the internal space of the supply path 2a of the cell stack 1. Has been. The flow rate adjusting member 6 has a partition surface 6c as a side wall surface corresponding to a long side of a rectangular cross section orthogonal to the longitudinal direction. The partition surface 6c faces the center side of the cell stack 1 when the flow rate adjusting member 6 is disposed in the supply path 2a, that is, the surface facing the fuel gas flow path 71 of the separator 4 constituting the cell stack 1. It becomes. The partition surface 6c is provided with a plurality of slits 60, 60a as openings penetrating the plate surface of the partition surface 6c. Each of the plurality of slits 60, 60a has a rectangular shape in which each side is parallel to the side of the partition surface 6c, and the plurality of slits 60, 60a are substantially equally spaced and substantially along the longitudinal direction of the flow rate adjusting member 6. They are arranged in parallel. The number and position of the slits 60 in the partition surface 6c correspond to the number and position of the fuel gas flow paths 71 of the separators 4 in each layer in a state where the flow rate adjusting member 6 is disposed in the supply path 2a of the cell stack 1. ing. The flow rate adjusting member 6 is made of a metal material having heat resistance such as stainless steel.

  Further, in the flow rate adjusting member 6, the opening area of the slit 60a at the central portion along the longitudinal direction of the partition surface 6c is such that the slit 60 on one end side and the slit 60 on the other end side along the longitudinal direction of the partition surface 6c. It is provided wider than the opening area. Here, the opening area of each slit 60 is changed by changing the length (height h) of each side of each slit 60 along the longitudinal direction of the partition surface 6c. In the illustrated form, the opening area of the slit 60a at the center in the longitudinal direction is the largest, and the opening area of the slit 60 gradually decreases toward both ends in the longitudinal direction. The opening area of each slit 60 is symmetrical from the central slit 60a toward both ends. In addition, the opening area of the slit 60 is the smallest, but is smaller than the cross-sectional area perpendicular to the direction in which the groove of the fuel gas passage 71 of the separator 4 runs.

  As shown in FIG. 1, the flow rate adjusting member 6 is disposed in the supply path 2 a through which the fuel gas G <b> 2 introduced into the fuel electrode 33 flows in the cell stack 1. At this time, the flow rate adjusting member 6 is inserted along the longitudinal direction of the flow direction of the fuel gas G2 in the supply path 2a of the cell stack 1. When the flow rate adjusting member 6 is disposed in the internal space of the supply path 2a, the flow rate adjusting member 6 moves to the internal space of the supply path 2a so that each slit 60 faces each of the fuel gas flow paths 71 shown in FIG. The insertion position is defined. The flow rate adjusting member 6 is fixed to the single cell 30 and the separator 4 constituting the cell stack 1 with a heat resistant adhesive, and the cell stack 1 is provided as an integral structure to which the flow rate adjusting member 6 is fixed. Yes.

  In this way, the flow rate adjusting member 6 is arranged in the internal space of the supply passage 2a, and the fuel gas G2 is introduced into the cylindrical hollow portion 6b of the flow rate adjusting member 6 from one end in the longitudinal direction (the lower end in FIGS. 1 and 3). Then, the fuel gas G2 passes through the slit 60 and flows out from the hollow portion 6b to the fuel gas channel 71 of each separator 4. Here, airtightness is ensured inside and outside the outer wall surface of the rectangular tube constituting the flow rate adjusting member 6, and the fuel gas G <b> 2 is supplied to the fuel gas flow channel 71 of the separator 4 only from the slit 60. Thereby, in each layer from the upstream to the downstream along the direction X in which the plurality of single cells 30 and the plurality of separators 4 of the cell stack 1 are alternately stacked, the fuel gas flow paths 71 of the separators 4 The fuel gas G <b> 2 is supplied to the fuel electrode 33 of the single cell 30.

  At this time, as described above, the opening area of each slit 60 is set to be smaller than the cross-sectional area of the fuel gas channel 71 of the separator 4, so that the fuel gas channel 71 of each separator 4 is supplied. The flow rate of the fuel gas G2 is defined according to the opening area of each corresponding slit 60. That is, the larger the opening area of each slit 60, the larger the flow rate of the fuel gas G2 supplied to the fuel gas flow path 71 of the corresponding separator 4, and the flow rate of the fuel gas G2 is approximately proportional to the opening area of the slit 60. To do. As described above, the opening areas of the slits 60 provided on the partition surface 6c of the flow rate adjusting member 6 are different from each other. Therefore, the flow rate of the fuel gas G2 supplied through the slit 60 to the fuel gas flow channel 71 of the separator 4 in each layer along the direction X in which the single cell 30 and the separator 4 are stacked is different in each layer. Become. That is, along the direction X, the flow rate of the fuel gas G2 introduced into the fuel gas flow path 71 of the corresponding separator 4 increases as the position where the slit 60 having a large opening area is provided.

  As described above, in the cell stack 1, the distribution amount of the fuel gas G2 supplied to each single cell 30 via each separator 4 can be set according to the opening area of the slit 60 provided in the flow rate adjusting member 6. it can. And the distribution for every single cell 30 can be formed in the flow volume of the fuel gas G2 supplied to each single cell 30 via each separator 4 by making the opening area of each slit 60 different. As shown in FIG. 3, the opening area of the slit 60a at the central portion with respect to the longitudinal direction of the partition surface 6c is compared with the opening areas of the upper slit 60 and the lower slit 60 with respect to the longitudinal direction of the partition surface 6c. Thus, by using the flow rate adjusting member 6 that is widely provided, the distribution amount of the flow rate of the fuel gas G2 supplied to the central portion of the flow path of the supply path 2a along the stacking direction X is changed to the flow rate of the supply path 2a. This is larger than the distribution amount of the flow rate of the fuel gas G2 supplied above and below the path.

  By adjusting the flow rate of the fuel gas G2 supplied to each single cell 30, the state of each single cell 30 during power generation can be controlled. Therefore, it is possible to control the state during power generation for each single cell 30 by making the opening area of each slit 60 provided in the flow rate adjusting member 6 different. For example, by forming a distribution in the supply amount of the fuel gas G2 to each unit cell 30, it is possible to suppress variations in unintended states that occur during power generation between the unit cells 30, such as variations in power generation amount and temperature. By doing so, the power generation efficiency of the cell stack 1 can be increased. Alternatively, an uneven distribution can be intentionally formed in the state during power generation between the single cells 30.

  In the cell stack 1 according to the present embodiment described above, the difference in the amount of heat generated during power generation that may be caused by the difference in the position along the X direction in the cell stack 1 is the distribution amount of the fuel gas G2 to the single cell 30. The distribution is relaxed by forming a distribution. If the flow rate adjusting member 6 is not provided in the cell stack 1, the fuel gas G2 introduced into the supply channel 2a flows directly from the supply channel 2a to the fuel gas channel 71, and the fuel electrode 33 of the single cell 30. To be supplied. In the cell stack 1, the fuel gas G <b> 2 supplied to the single cell 30 is used as a reaction gas in the fuel electrode 33, and power is generated in each single cell 30 constituting the cell stack 1. At this time, in the central unit cell 30 along the stacking direction X of the cell stack 1, heat generation due to power generation occurs inside compared to the upper and lower unit cells 30 along the stacking direction X. Therefore, the temperature of the single cell 30 in the central portion along the stacking direction X tends to be higher than the temperature of the single cell 30 above and below. When the temperature of the single cell 30 at the time of power generation increases, the single cell 30 is deteriorated.

  Further, when the temperature of the single cell 30 or the separator 4 increases, the gas viscosity of the fuel gas G2 flowing through the fuel gas flow path 71 increases, and the fuel gas G2 is less likely to be supplied to the fuel electrode 33. Then, the single cell 30 must generate power with a small amount of the fuel gas G2. When the flow rate of the fuel gas G2 supplied to each single cell 30 is small in comparison with the amount of power generation, the fuel utilization rate decreases. However, the power generation is performed under conditions where the fuel utilization rate is low. Deterioration is likely to occur. In addition, when a certain single cell 30 generates power with a small amount of fuel gas G2, the internal resistance of the single cell 30 increases and the amount of power generation decreases. Since each single cell 30 constituting the cell stack 1 is electrically connected in series and the amount of electricity flowing through all the single cells 30 is the same, an increase in internal resistance occurs in some of the single cells 30, When the power generation amount becomes small, the power generation amount of all the single cells 30 is limited according to the single cell 30. Therefore, when the internal resistance of the single cell 30 in the central portion of the laminated structure increases as a result of the increase in the gas viscosity of the fuel gas G2 due to heat generation, not only the single cell 30 but also all the single cells 30 constituting the cell stack 1. The amount of power generation is limited, and the amount of power generation is reduced in the entire cell stack 1.

  Furthermore, if power generation is performed with the internal resistance of the single cell 30 increased, the amount of heat generated by the single cell 30 will increase further. As a result, the temperature of the central portion of the cell stack 1 becomes higher, the increase in gas viscosity, the accompanying increase or deterioration of the internal resistance of the single cell 30, and the decrease in the amount of power generation in the entire cell stack 1 are accelerated. There is also the possibility of progress.

  Therefore, by inserting the flow rate adjusting member 6 whose opening area of the slit 60 is large in the central portion in the longitudinal direction and small in the end portion into the supply path 2 a of the cell stack 1, along the stacking direction X of the cell stack 1. By increasing the distribution amount of the flow rate of the fuel gas G2 supplied to the central unit cell 30 compared to the distribution amount of the flow rate of the fuel gas G2 supplied to the upper and lower unit cells 30, the gas viscosity is increased at a high temperature. The fuel gas G2 is also easily supplied to the single unit cell 30 in the central portion along the stacking direction X, and a substantial flow rate of the fuel gas G2 (actually flows through the fuel gas passage 71 for power generation). The uniformity of the amount of fuel gas G2 that can be used can be enhanced throughout the stack structure. Thereby, the variation in the amount of power generation of each single cell 30 constituting the cell stack 1 can be reduced, and the single cells 30 in the central portion in the stacking direction X that are likely to increase in gas viscosity due to high temperature are electrically connected in series. Moreover, the situation where the power generation amount of each single cell 30 is limited can be alleviated. As a result, the power generation efficiency can be increased as the entire cell stack 1.

  Further, in the central unit cell 30, the amount of fuel gas G2 supplied to the fuel electrode 33 is increased and the fuel utilization rate is decreased, thereby reducing internal resistance and suppressing heat generation in the central unit cell 30. can do. As a result, it is possible to suppress the temperature rise itself at the central portion and make it difficult for the gas viscosity to rise due to high temperature. Then, it is limited to the single cell 30 in the central part of the multilayer structure, and it is difficult to generate a situation where the power generation amount of the entire multilayer structure is limited. Further, in the single cell 30 in the central portion in the stacking direction, which is easily exposed to a harsh environment due to heat generation, it is possible to suppress deterioration due to the high fuel utilization rate, and the power generation efficiency of the cell stack 1 can be increased for a long time. Easy to maintain over.

  As described above, the deterioration of the single cell 30 in the central portion and the decrease in the heat generation efficiency of the entire cell stack 1 that may occur due to heat generation in the central portion of the stacked structure of the cell stack 1 are reduced in the opening area of the slit 60 in the central portion. By disposing the increased flow rate adjusting member 6 in the supply path 2a for the fuel gas G2, it is possible to relax and improve the durability and power generation efficiency of the cell stack 1. Even if the amount of the fuel gas G2 supplied to the fuel electrode 33 of the single cell 30 in the central portion of the laminated structure is excessively increased, the heat generation of the single cell 30 may be promoted by the increase in the amount of power generation. Therefore, the opening area of the slit 60a in the central portion does not promote the heat generation due to such an increase in the amount of power generation, and the effect of substantially equalizing the flow rate of the fuel gas G2 and the internal due to the increase in the fuel utilization rate. It is preferable to keep it within a range where the effect of reducing the resistance is obtained.

  As another form of mitigating the difference in the power generation state of the single cell 30 that may occur depending on the position in the cell stack 1 by using the flow rate adjusting member 6 having the slits 60 having different opening areas, “other implementations” will be described later. As will be described as “form”, a form in which the power generation state caused by the pressure distribution of the fuel gas G2 flowing through the supply path 2a is relaxed can be mentioned. The state of the single cell 30 during power generation depends on both the amount of heat generation and the pressure of the fuel gas G2 in the supply path 2a, and the opening area of the slit 60 of the flow rate adjusting member 6 depends on which one is focused on mitigating the influence. Depending on the position, how to set can vary. Depending on the specific configuration of the cell stack 1 and the specific power generation conditions, if the opening area of each slit 60 is set so that the larger effect can be reduced or both effects can be reduced Good.

  As described above, the flow rate adjusting member 6 having the slits 60 having different opening areas is used to adjust the flow rate of the fuel gas G2 supplied to each single cell 30 via each separator 4, thereby being described in Patent Document 1. As described above, the flow rate of the fuel gas G2 can be adjusted without depending on the design of the fuel gas passage 71 in the separator 4. Further, at least a part, preferably all, of the separators 4 constituting the cell stack 1 can be configured as the separators 4 of the same design having the fuel gas flow paths 71 having the same shape and arrangement. Therefore, the single cell 30 can be connected via the fuel gas passage 71 of each separator 4 without designing and manufacturing a large number of separators 4 having different shapes and arrangements of the fuel gas passage 71. The flow rate of the supplied fuel gas G2 can be variously adjusted. Moreover, such flow rate adjustment can be achieved by simply inserting the flow rate adjusting member 6 having a simple structure having the slit 60 in the wall surface of the cylindrical body into the internal space of the supply path 2a of the cell stack 1. Therefore, the cell stack 1 that can freely set the distribution of the flow rate of the fuel gas G2 can be manufactured with a simple configuration and at a low cost.

  In the embodiment described above, the flow rate adjusting member 6 is fixed to the inner wall surface 20 of the supply path 2a through which the fuel gas G2 introduced into the fuel electrode 33 flows. Therefore, the ratio of the flow rate distribution of the fuel gas G2 to each single cell 30 set at the time of designing the flow rate adjusting member 6 and the cell stack 1 is maintained over time. Thereby, the influence of the distribution of the power generation state with little temporal change can be steadily eased like the distribution of the calorific value that is larger than the both end portions in the central portion in the X direction of the laminated structure described above.

  The flow rate adjusting member 6 has a partition surface 6c that partitions between the supply path 2a and the fuel gas flow path 71 of each separator 4, and blocks the flow of the fuel gas G2 between the two, and opens to the partition surface 6c. A specific structure is not particularly limited as long as it has a plurality of slits 60 having different areas. However, as described above, by forming the partition surface 6c as a part of the wall surface of the cylindrical body, the partition surface 6c has a simple configuration, can be easily manufactured, and can easily be supplied to the supply path 2a of the cell stack 1. It can be set as the flow volume adjustment member 6 which can be inserted and inserted in internal space. The fuel gas G2 having a flow rate corresponding to the opening area of each slit 60 is supplied to the fuel gas passage 71 of each separator 4 while ensuring airtightness in the hollow portion of the supply passage 2a with respect to the internal space of the flow rate adjusting member 6. It becomes possible to supply. In addition, by configuring the flow rate adjusting member 6 as a cylindrical member as described above, it is possible to improve the accuracy and simplicity of assembling the cell stack 1. That is, when assembling a laminated structure composed of the SOFC single cell unit 3 and the separator 4, the cylindrical flow rate adjusting member 6 is inserted into the fuel gas passage holes 7 and 9 in order of the SOFC single cell unit 3 and the separator 4 one by one. Thus, the positioning between each single cell 30 and the separator 4 and the positioning between the stacked structure of the SOFC single cell unit 3 and the separator 4 and the flow rate adjusting member 6 can be easily achieved. .

  In the above-described embodiment, the flow rate adjusting member 6 is disposed in the supply path 2a, but may be disposed in the supply path 2b instead of or in addition to the supply path 2a. Further, instead of the supply paths 2a and 2b for supplying the fuel gas G2 to the cell stack 1, or in addition to the supply paths 2a and 2b for supplying the fuel gas G2, the flow rate adjusting member 6 is supplied with the air electrode gas G1. It can also be disposed on the paths 1a and 1b. When the flow rate adjusting member 6 is disposed in the supply paths 1 a and 1 b for supplying the air electrode gas G 1, each single cell is connected via the air flow path 81 of the separator 4 of each layer along the stacking direction X of the cell stack 1. By setting the opening area of the slit 60 of the flow rate adjusting member 6 according to the flow rate of the air electrode gas G1 to be supplied to the 30 air electrodes 32, the separator 4 of each layer along the stacking direction X of the cell stack 1 is set. It is possible to set the distribution amount of the flow rate of the air electrode gas G1 supplied to each single cell 30 via the. Thereby, the electric power generation state resulting from the temperature distribution in each layer single cell 30, the pressure distribution of the air electrode gas G1, etc. is controllable.

  In particular, the air electrode gas G1 can be effectively used for cooling the single cell 30 during power generation. That is, the supply path 1a of the air electrode gas G1, so that a large amount of the air electrode gas G1 can be supplied to a place where the temperature tends to be high, such as the single cell 30 in the central portion in the stacking direction X of the cell stack 1 described above. By setting the opening area of the slit 60 of the flow rate adjusting member 6 provided in 1b, it is possible to suppress such a high temperature. However, as described above, in the case where the flow rate adjusting member 6 is provided for the purpose of relaxing the distribution of the calorific value that increases at the center along the stacking direction X of the cell stack 1, the supply path through which the fuel gas G2 flows is provided. Providing the flow rate adjusting member 6 in 2a and 2b is more effective in relaxing the calorific value distribution than providing it in the supply passages 1a and 1b through which the air electrode gas G1 flows.

[Other Embodiments]
In addition to the above embodiment, depending on the specific configuration, arrangement, and use conditions of the cell stack 1, the setting of the opening area of the slit 60 of the flow rate adjusting member 6 may affect the variation of the power generation state of the single cell 30. Can be relaxed. Hereinafter, a plurality of forms will be briefly described. The description of the configuration common to the above embodiment is omitted.

(1) Mitigation of the effect of pressure loss When fuel gas G2 is introduced from one end of the elongated supply passage 2a and reaches the other end, it is connected in a direction connecting the upstream and downstream of the supply passage 2a by dynamic pressure and / or static pressure. Depending on the position along, the fuel gas G2 has a non-uniform distribution of pressure. If the fuel gas G2 is supplied directly from the supply passage 2a to the fuel gas passage 71 of each separator 4 having the same cross-sectional area without using the flow rate adjusting member 6, the pressure of the fuel gas G2 in the supply passage 2a At a higher position, the fuel gas flows out into the fuel gas passage 71 and the flow rate of the fuel gas G2 used for power generation in the single cell 30 increases. Therefore, as described above, the flow rate adjustment is such that the opening area of the slit 60 is small at the position where the pressure of the fuel gas G2 in the supply passages 2a and 2b increases and increases at the position where the pressure decreases along the longitudinal direction. The member 6 may be used. Thereby, the non-uniform distribution of the pressure of the fuel gas G2 corresponding to the position connecting the upstream and the downstream of the supply path 2a can be alleviated, and in the cell stack 1 during power generation due to the pressure distribution of the fuel gas G2. The difference in the state of the single cell 30 can be reduced.

  For example, when the cell stack 1 is in a high-pressure loss state in which the fuel gas G2 is less likely to flow in the layers that are lower in the stacking direction X of the cell stack 1 than in the upper direction, It is conceivable that the opening area of the slit 60 becomes wider as it becomes lower than the upper side along the longitudinal direction of the slit 60. That is, the opening area of the slit 60 of the flow rate adjusting member 6 flowing in the upper layer having a low pressure loss is provided narrow, and the opening area of the slit 60 flowing in the lower layer having a high pressure loss is provided wide. Thus, by providing the opening area of the slit 60 wider as the layer becomes lower along the stacking direction X of the cell stack 1, the upper cell also in the lower single cell 30 along the stacking direction X of the cell stack 1. As with the single cell 30, the amount of the fuel gas G <b> 2 substantially supplied to the fuel electrode 33 can be secured, and the uniformity of the amount of fuel gas G <b> 2 supplied in the entire cell stack 1 can be improved. Similarly, the air electrode gas G1 can alleviate non-uniformity in the supply amount to each single cell 30 due to pressure loss.

(2) Mitigation of non-uniformity in a single fuel cell So far, in the cell stack 1 in which a large number of single cells 30 are stacked, the power generation state and the amount of heat that can be generated between the layers along the stacking direction X In the above description, the non-uniformity is alleviated by adjusting the flow rate distribution of the fuel gas G2 and the air electrode gas G1 by setting the opening area of the slit 60 of the flow rate adjusting member 6. In addition to such non-uniformity between layers, there is a possibility that non-uniformity may occur at each location in the power generation state and the amount of heat generated in each single cell 30 constituting each layer of the cell stack 1. This non-uniformity can be alleviated by the flow rate adjusting member 6 having the slit 60. Such mitigation of the non-uniformity of the power generation state in the layer is achieved by changing the opening shape of each slit 60 of the flow rate adjusting member 6 from the rectangle as in the above-described embodiment, and opening dimensions at each part in the layer. This can be achieved by providing a distribution. For example, the height h may be changed for each position in each slit 60.

  In each layer along the stacking direction X of the cell stack 1, the fuel gas G <b> 2 circulates only through the fuel gas passage 71 at the center of the single cell 30 among the many groove-like fuel gas passages 71 arranged in parallel. As a result, it may be difficult for the fuel gas G2 to flow through the fuel gas channel 71 at the end of the single cell 30. In this case, the shape of the opening of each slit 60 is not a rectangle, but both end portions along the width direction in the width direction of the slit 60 (direction perpendicular to the height direction h) compared to the center portion. Thus, the opening height h can be increased. That is, it is possible to provide a substantially drum-shaped opening shape in which the height h of the slit 60 becomes lower as it approaches the central portion than both ends along the width direction of the slit 60. Thereby, compared with the center part of the single cell 30, a large amount of fuel gas G2 can be supplied to the edge part of the single cell 30. FIG. Therefore, in each layer along the stacking direction X of the cell stack 1, the flow rate distribution of the fuel gas G2 at each location in the single cell 30 can be relaxed.

  Also for the air electrode gas G1, the supply amount to the air electrode 32 of the single cell 30 of each layer is determined by the opening shape of each slit 60 of the flow rate adjusting member 6 disposed in the supply path 1a, 1b of the air electrode gas G1. It can be adjusted according to the position within 30. For example, as described above, the central portion of the stacked structure of the cell stack 1 is more likely to be heated up than the end portion (outer peripheral portion) of the surface of the single cell 30 in the single cell 30. , It is difficult to dissipate heat, and it tends to become high temperature. Therefore, a larger amount of the air electrode gas G1 is supplied to the central portion of the single cell 30 than at the end portion, and the cooling effect by the air electrode gas G1 can be obtained at the central portion of the single cell 30 more than at the end portion. It is conceivable to do so. In this case, each opening shape of the slit 60 of the flow rate adjusting member 6 disposed in the supply path 1a, 1b of the air electrode gas G1 is higher in the central portion along the width direction than in the end portion. It should just be. That is, each slit 60 may be formed in a shape like a biconvex lens in which the height h increases as it approaches the center from both ends along the width direction. Thereby, compared with an edge part, the large amount of air electrode gas G1 distribute | circulates to the center part, and the single cell 30 center part which is easy to generate | occur | produce heat | fever can be cooled efficiently.

(3) Mitigation of non-uniformity of the power generation state among a plurality of fuel cell single cells In addition, a power generation module is constructed in which a high temperature control unit such as a large number of cell stacks 1, reformers, and fuel units is covered with a heat insulating material There is a case. At this time, due to the mutual arrangement of the plurality of cell stacks 1, the arrangement relationship with other devices, the configuration of the supply path for supplying the fuel gas G 2 and the air electrode gas G 1 to the many cell stacks 1, etc. There may be a difference in the power generation state or the amount of heat generated between the cell stacks 1. Such a difference in the power generation state and the amount of heat generated between the cell stacks 1 can be alleviated by the flow rate adjusting member 6 provided in each cell stack 1.

  For example, in the power generation module, the fuel gas G2 easily circulates in the plurality of cell stacks 1 in the power generation module due to the piping configuration of the supply paths 2a and 2b for supplying the fuel gas G2 to each cell stack 1. Cell stack 1 and the cell stack 1 in which the fuel gas G2 is difficult to flow may appear. Specifically, there is a case where the fuel gas G2 is more likely to enter the cell stack 1 that is closer to the inlet side of the fuel gas G2 supply paths 2a and 2b, and the fuel gas G2 is less likely to enter the cell stack 1 that is closer to the outlet side of the fuel gas G2. Conceivable. In this case, a plurality of types of flow rate adjusting members 6 having different sums of the opening areas of the slits 60 are used, and the flow rate adjusting members 6 having a small sum of the opening areas are provided in the cell stack 1 in which the fuel gas G2 easily flows. A flow rate adjusting member 6 having a large sum of opening areas can be disposed in the cell stack 1 where the fuel gas G2 is difficult to flow. Thereby, the distribution of the fuel gas G2 between the cell stacks 1 constituting the power generation module can be relaxed, the power generation efficiency of each cell stack 1 can be made uniform, and the power generation efficiency of the entire power generation module can be improved. .

  Among the plurality of cell stacks 1, the cell stack 1 surrounded by another cell stack 1, the cell stack 1 disposed in the vicinity of other heat generating components such as a reformer, It is less likely to dissipate heat than the cell stack 1 and tends to be hot. Therefore, in the cell stack 1 that tends to be high in temperature, the flow rate adjusting member 6 having a larger sum of the opening areas of the slits 60 than the cell stack 1 that is unlikely to become high temperature is provided with the supply paths 1a and 1b of the air electrode gas G1. It is sufficient to arrange them. Thereby, the cell stack 1 which tends to become high temperature due to the arrangement can be efficiently cooled.

  The present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the spirit of the present invention.

1 Cell stack (solid oxide fuel cell)
1a, 1b Supply path (internal manifold)
2a, 2b Supply path (internal manifold)
3 SOFC single cell unit (fuel cell single cell unit)
4 Separator 6 Flow rate adjusting member 6b Hollow portion 6c of flow rate adjusting member 6 Partition surface 7 of flow rate adjusting member 6 Fuel gas passage hole (vent hole)
8 Air passage hole (vent hole)
9 Fuel gas passage hole (vent hole)
10 Air passage hole (vent hole)
20 inner wall surface 30 single cell (fuel cell single cell)
31 Electrolyte layer (solid oxide electrolyte)
32 Air electrode 33 Fuel electrode 60, 60a Slit (opening)
71 Fuel gas flow path (gas flow part)
81 Air flow path (gas flow part)
G1 Air electrode gas G2 Fuel gas

Claims (11)

A plurality of fuel cell single cells provided with an air electrode and a fuel electrode on both sides of the solid oxide electrolyte;
A cell in which an air electrode gas containing oxygen to be introduced into the air electrode and a plurality of plate-like separators having gas circulation portions as flow paths through which the fuel gas introduced into the fuel electrode can be circulated are alternately stacked. In a solid oxide fuel cell having a stack,
At least one of the air electrode gas and the fuel gas passes through an internal manifold in which a fuel cell single cell unit including the plurality of fuel cell single cells and a vent hole penetrating the plurality of separators are communicated. And supplied to the gas circulation part provided in each of the plurality of separators,
The solid oxide fuel cell further includes a flow rate adjusting member that is disposed in the internal manifold and has a partition surface that partitions the internal manifold and the gas flow part.
The flow rate adjusting member has a plurality of openings through which the gas in the internal manifold can be circulated to each of the gas circulation portions on the partition surface, and at least a part of the opening area of the plurality of openings is Solid oxide fuel cells, which are different from each other.   2. The solid oxide fuel cell according to claim 1, wherein at least some of the plurality of separators have the same shape and arrangement of the gas flow portion. The flow rate adjusting member is a cylindrical body having a hollow portion through which gas supplied to the internal manifold flows, and is inserted into the internal manifold,
The partition surface provided with the opening is an outer wall of the cylindrical body facing the gas circulation part, and the gas supplied to the internal manifold circulates through the hollow part and flows through the gas from the opening. 3. The solid oxide fuel cell according to claim 1, wherein the solid oxide fuel cell flows out to a portion.   4. The solid oxide according to claim 1, wherein the flow rate adjustment member is inserted into the internal manifold and fixed to the single fuel cell and the separator. 5. Fuel cell.   5. The solid oxide fuel according to claim 1, wherein the flow rate adjusting member is disposed in the internal manifold through which a fuel gas introduced into the fuel electrode flows. battery.   The flow rate adjusting member is provided with a plurality of openings in the partition surface, and the openings in the central portion along a direction in which the plurality of fuel cell single cells and the plurality of separators are alternately stacked. 6. The solid oxide fuel cell according to claim 1, wherein the opening area is larger than the opening area of the opening at the end. 6.   In at least some of the plurality of openings, a dimension in a direction in which the plurality of single fuel cell units and the plurality of separators are alternately stacked is distributed along a direction intersecting the direction. The solid oxide fuel cell according to claim 1, comprising:   The solid oxide fuel cell has a plurality of the cell stacks, and the sum of the opening areas of the flow rate adjusting members disposed in the internal manifold of each cell stack is different from each other. The solid oxide fuel cell according to any one of claims 1 to 7, wherein: A plurality of fuel cell single cells each provided with an air electrode and a fuel electrode on both surfaces of a solid oxide electrolyte, an air electrode gas containing oxygen introduced into the air electrode, and a fuel gas introduced into the fuel electrode can be circulated. In a flow rate adjusting member provided in a solid oxide fuel cell in which a plurality of plate-like separators having gas flow portions as flow paths are alternately stacked,
The flow rate adjusting member is disposed in an internal manifold formed by communicating a fuel cell single cell unit including the plurality of fuel cell single cells and a vent hole penetrating the separators, and the internal manifold and the A partition surface for partitioning between the gas flow portions, the partition surface having a plurality of openings provided at positions corresponding to the gas flow portions, and at least one of the plurality of openings. The opening area of each part is different from each other.   The opening area of the opening at the center portion with respect to the longitudinal direction of the partition surface is wider than the opening area of the opening at the end portion with respect to the longitudinal direction of the partition surface. Item 10. The flow rate adjusting member according to Item 9.   The dimension of the direction with respect to the longitudinal direction of the partition surface in at least some of the plurality of openings has a distribution along a direction intersecting the direction. The flow rate adjusting member according to 10.

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