JPH06290804A - Fuel cell - Google Patents

Abstract

PURPOSE:To prevent a gas including oxygen or a fuel gas from leakage to the outside and to reduce a cost by providing a heat insulating body surrounding a cell accumulated body. CONSTITUTION:A heat insulating material 32 is arranged so as to surround a cell accumulated body U, in which plural cells C are parallelly layered. In the heat insulating material 32, a clearance part 33, which communicates with a penetrating hole 31C formed in a bottom part 3lB of a box body 31, is arranged. A fuel gas supply pipe 34 is communicably connected to the penetrating hole 31C. A gas including oxygen gas is supplied to an oxygen including gas passage S in each cells C via an external oxygen gas including gas supply pipe 36 and an internal oxygen gas including gas supply pipe 35, while a fuel gas F is supplied to a fuel gas passage in each cells C via the fuel gas supply pipe 34 and a fuel gas supply part Kf. In this way, power is generated in a cell layered part NC by the oxygen including gas and the fuel gas. Therefore, the heat insulating material 32 suppresses transmission of heat in the cell accumulated body to the box body 31, and a temperature rise in the box body can be suppressed, so that an inexpensive metal can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises an oxygen electrode on one surface of a plate-like electrolyte layer and a fuel electrode on the other surface thereof, and
A plurality of cells of a fuel cell having an oxygen-containing gas passage on the side facing the oxygen electrode and a fuel gas passage on the side facing the fuel electrode are juxtaposed in a stacked state, and the inlet of the oxygen-containing gas passage is provided. An oxygen-containing gas supply unit that communicates with each other, an oxygen-containing gas discharge unit that communicates with each outlet of the oxygen-containing gas passage, a fuel gas supply unit that communicates with each inlet of the fuel gas passage, and the fuel gas The present invention relates to a fuel cell in which a fuel gas discharge part communicating with each outlet of a flow path is provided to form a cell assembly, and the cell assembly is provided inside a box-shaped body.

[0002]

2. Description of the Related Art In such a fuel cell, in order to prevent the oxygen-containing gas and the fuel gas from leaking from the cell assembly to the outside, the cell assembly is provided inside an airtight box. By the way, during operation of the fuel cell, the temperature of the cell assembly becomes high, and the heat of the cell assembly is conducted to the box-shaped body to raise the temperature of the box-shaped body. Therefore, conventionally, the box-shaped body has high temperature heat resistance. It was made of ceramic material.

[0003]

However, since a ceramic material is hard to be processed because it has a high hardness and cannot be bent, a processing for forming a box-shaped body having an airtightness by using the ceramic material. Is complicated, and the ceramic material is expensive, so that the fuel cell is expensive.

The present invention has been made in view of the above circumstances, and an object thereof is to achieve the original purpose of preventing the oxygen-containing gas and the fuel gas from leaking to the outside by the box-shaped body. , To reduce the cost of fuel cells.

[0005]

A first characteristic structure of the fuel cell according to the present invention is that a heat insulator surrounding the cell assembly is provided.

In a second characteristic configuration, the heat insulator comprises any one of the oxygen-containing gas supply unit, the oxygen-containing gas discharge unit, the fuel gas supply unit and the fuel gas discharge unit. There is a point.

A third characteristic configuration is that the oxygen-containing gas discharge portion and the fuel gas discharge portion are discharged from the oxygen-containing gas passage outlet and the discharged oxygen-containing gas discharged from the oxygen-containing gas passage outlet. One of the oxygen-containing gas supply unit, the fuel gas supply unit, and the gas discharge unit, wherein the heat insulator is constituted by one gas discharge unit that functions as a combustion chamber that burns the discharged fuel gas. It is in the point of having one.

A fourth characteristic configuration is that the heat insulating body is formed of a porous material that allows gas to flow therethrough.

[0009]

According to the first characteristic configuration, the heat transfer of the heat of the cell assembly to the box-shaped body can be suppressed by the heat insulator, so that the temperature rise of the box-shaped body can be suppressed.

The operation of the second characteristic configuration is as follows. The oxygen-containing gas supply unit is formed, for example, by providing a box-shaped wind tunnel whose one side surface is open with the openings facing the respective inlets of the oxygen-containing gas flow path. Similarly, the oxygen-containing gas discharge unit, in a state in which the same wind tunnel faces the respective outlets of the oxygen-containing gas flow path, the fuel gas supply unit,
The similar gas tunnel is formed so as to face the inlets of the fuel gas passages, and the fuel gas discharge portion is formed by providing the same wind tunnel so as to face the outlets of the fuel gas passages. According to the second characteristic configuration, for example, a void portion corresponding to the internal space of the wind tunnel is formed in the heat insulator, and the void portion functions as a wind tunnel, whereby the oxygen-containing gas supply unit, the oxygen-containing unit Any one of a gas discharge part, a fuel gas supply part, and a fuel gas discharge part is provided. Therefore, among the oxygen-containing gas supply unit, the oxygen-containing gas discharge unit, the fuel gas supply unit and the fuel gas discharge unit, it is not necessary to provide a wind tunnel corresponding to one of the heat insulators in the cell assembly, Only the wind tunnels corresponding to each of the remaining three need only be provided in the cell stack.

The operation of the third characteristic structure is as follows. The oxygen-containing gas supply unit is formed, for example, by providing a box-shaped wind tunnel whose one side surface is open with the openings facing the respective inlets of the oxygen-containing gas flow path. Similarly, the fuel gas supply unit faces the inlets of the fuel gas flow passage with the same wind tunnel, and the gas discharge unit exposes the same wind tunnel with the outlets of the oxygen-containing gas flow passage and the fuel gas flow passage. Are formed so as to face the respective outlets of the. According to the third characteristic configuration, for example, a void portion corresponding to the inner space of the wind tunnel is formed in the heat insulator, and the void portion functions as a wind tunnel, thereby providing an oxygen-containing gas supply unit and a fuel gas. One of the supply unit and the gas discharge unit is provided. Therefore, it is not necessary to provide the wind tunnel corresponding to one of the oxygen-containing gas supply unit, the fuel gas supply unit, and the gas discharge unit, which is provided in the heat insulator, in the cell integrated body, and to correspond to each of the remaining two. It is only necessary to provide a wind tunnel to the cell assembly.

According to the fourth characteristic configuration, the heat insulator itself is
Since the gas is allowed to flow therethrough, it is not necessary to form, for example, a void portion in the heat insulator to function as a wind tunnel.

[0013]

According to the first characteristic configuration, since the temperature rise of the box-shaped body can be suppressed, it is not necessary to form the box-shaped body with a ceramic material as in the conventional case, and the cutting can be easily performed.
Since it can be bent and is easy to work, and can be formed of an inexpensive metal, the cost can be reduced as compared with the conventional case.

Further, according to the second characteristic configuration, the wind tunnel corresponding to any three of the oxygen-containing gas supply unit, the oxygen-containing gas discharge unit, the fuel gas supply unit and the fuel gas discharge unit is used as a cell. Since it only has to be provided on the integrated body, the cost can be further reduced.

Further, according to the third characteristic configuration, only the wind tunnels corresponding to any two of the oxygen-containing gas supply section, the fuel gas supply section and the gas discharge section may be provided in the cell assembly. Therefore, the cost can be further reduced.

Further, according to the fourth characteristic constitution, since it is not necessary to form a void portion for functioning as a wind tunnel in the heat insulating body, the cost can be further reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the drawings. First, the structure of the cell C of the fuel cell will be described with reference to FIG.

A film-shaped or plate-shaped solid electrolyte layer 1 having a rectangular planar shape is formed on one surface of the plate-shaped solid electrolyte layer 1 with the electrolyte layer exposed portions 1a extending over the entire length of the side edges at both side edges of the plate-shaped solid electrolyte layer 1. -Shaped oxygen electrode 2 is integrally attached, and a film-like or plate-like fuel electrode 3 is integrally attached to the other surface over the entire surface or almost the entire surface. A three-layer plate having a rectangular planar shape for obtaining an electromotive force is formed.

The solid electrolyte layer 1 is composed of tetragonal ZrO ₂ in which about 3 mol% Yt is dissolved, and other suitable materials, and the oxygen electrode 2 is composed of LaMnO ₃ and other suitable materials. The fuel electrode 3 is composed of a cermet of Ni and ZrO ₂ , or any other suitable material.

The plate-shaped portion 4a, a pair of strip-shaped projections 4b located at both ends of the plate-shaped portion 4a, and a plurality of ridges 4c located between the pair of strip-shaped projections 4b are integrated. A pair of strip-shaped projections is formed on the formed conductive separator 4 in a state where the plate-like portion 4a faces the oxygen electrode 2 with a space therebetween and each of the plurality of protrusions 4c contacts the oxygen electrode 2. 4b is attached to each of the electrolyte layer exposed portions 1a so as to be attached to the side facing the oxygen electrode 2.

As a result, the conductive separator 4 and the oxygen electrode 2 are connected in a conductive state, and a plurality of groove-shaped oxygen-containing gas flow paths s are formed between the pair of strip-shaped projections 4b. Further, when viewed in the flow direction of the oxygen-containing gas flow path s, the peripheral portion between the conductive separator 4 and the three-layer plate-like body is a fuel gas flow path f which is partitioned from the oxygen-containing gas flow path s. Then, of the openings formed by the conductive separator 4 and the three-layer plate on each of the opposite side surfaces of the cell C, one is the oxygen-containing gas flow path inlet si and the other is the oxygen-containing gas flow path outlet so. There is.

The conductive separator 4 forms the oxygen-containing gas flow path s as a partition and also forms the oxygen electrode 2
Also serves as a cell terminal for deriving a current from. Then, the plurality of ridges 4c are brought into contact with the oxygen electrode 2 to increase the cross-sectional area of the electric passage from the oxygen electrode 2 to the conductive separator 4 as the cell terminal.

The conductive separator 4 is made of a conductive ceramic material such as LaCrO ₃ having excellent resistance to oxidation and reduction.

Next, with reference to FIG. 2 to FIG. 4, a specific structure of the cell stacking portion NC in which a plurality of the cells C configured as described above are juxtaposed in a stacked state while being electrically connected in series will be described.

In the cell C, on each of the pair of side surfaces on the side where the oxygen-containing gas flow passage s is closed by the conductive separator 4, the first side having a thickness substantially equal to that of the cell C and longer than the cell C is formed.
While making the columnar body 5 and the second columnar body 6 adhere to each other,
The third columnar body 7 and the fourth columnar body 8 having the same thickness as each other and longer than the cell C are brought into close contact with the pair of edge portions of the cell C on which the oxygen-containing gas flow channel s is opened, And the first
Both ends of the third columnar body 7 and the fourth columnar body 8 are overlapped and closely adhered to both ends of the columnar body 5 and the second columnar body 6, respectively. Further, the cell C and the first columnar body 5 and the second columnar body 6 are repeatedly stacked on the third columnar body 7 and the fourth columnar body 8. Therefore, a plurality of cells C are juxtaposed in a stacked state with a space defined as the fuel gas flow path f between adjacent cells C and C.

At the end portion of the cell C on the side of the oxygen-containing gas flow path si, between the side surface of the cell C and the first and second columnar bodies 5 and 6, and the edge portion of the cell C and the first columnar body 5, 6, respectively. An adhesive 9 having heat resistance and electrical insulation is filled between the four columnar bodies 8 to prevent the oxygen-containing gas from leaking to other than the oxygen-containing gas passage s.

Further, a flexible conductive material 10 formed in a shape that allows gas flow is filled between the adjacent cells C, C. That is, the flexible conductive material 10 causes the adjacent cells C,
It is configured to connect Cs to each other in a conductive state.

The pillars 5, 6, 7, 8 are made of a ceramic material having excellent heat resistance and electrical insulation. The flexible conductive material 10 is made of a Ni felt-like material having excellent heat resistance and reduction resistance, or any other suitable material.

The fuel gas passage f will be specifically described. A recess 7A is formed in the third columnar body 7 so as to form an opening with the fuel electrode 3 of the cell C. In addition, the openings formed between the first columnar bodies 5 and 5 adjacent to each other in the stacking direction of the cells C, and the second columnar bodies 6 and 6 adjacent to each other in the stacking direction.
Each of the openings formed between the openings is provided with a flow path inlet forming member 11 in a state of forming an opening portion on the oxygen-containing gas flow path inlet si side of the opening. Each of the openings formed by the flow path inlet forming member 11 serves as a fuel gas flow path inlet fi, and each of the recesses 7A serves as a fuel gas flow path outlet fo. That is, the fuel gas passage f is configured such that the fuel gas flows from the fuel gas passage inlets fi and fi on both sides to the fuel gas passage outlet fo in a bent flow state through the flexible conductive material 10. .

The cell stacking portion NC is constructed as described above.

Next, the structure of the cell assembly U will be described with reference to FIGS. The third columnar body 7 and the fourth columnar body 8 are provided at both ends of the cell stacking portion NC in the stacking direction in the same manner as described above, and the end surface M in the stacking direction is provided on the third columnar body 7 and the fourth columnar body 8. With the entire cover of
A base plate 12 is attached. A through hole 12A is formed substantially in the center of the base plate 12. Base plate 12
Is made of the same material as the third columnar body 7 and the fourth columnar body 8.

Between the end face M and the base plate 12, there is arranged a terminal portion 20 for taking out electric power from the end portion of the cell laminated portion NC in the laminating direction. A description of the terminal portion 20 will be added. The terminal portion 20 is provided between the end face M and the base plate 12 in a state of being in contact with the end face M, and has a conductive collector portion A, and one end portion is connected to the collector portion A and the other end portion is connected. A rod-shaped body 2 which is provided in a state of protruding from the through hole 12A formed in the base plate 12 to the outside of the base plate 12 and has conductivity.
1 and a fixing portion B for fixing the rod-shaped body 21 to the base plate 12.

The fixed portion B will be further described. The fixed portion B is a male screw portion 21A formed on the outer peripheral portion of the rod-shaped body 21.
And a nut member 22 screwed to the male screw portion 21A.

The current collector A will be further described. The current collector A is connected to the rod-shaped body 21 and is a plate-shaped body 2 having conductivity.
3 and a flexible conductive material 24 provided between the plate 23 and the end face M. The flexible conductive material 2
4 is formed in a shape that allows the flow of gas.

Rod-like body 21, nut member 22 and plate-like body 2
3 is made of a material having excellent heat resistance and electric conductivity, such as Ni, and the flexible conductive material 24 is made of a material having excellent heat resistance and electric conductivity, such as a felt material of Ni.

As shown in FIGS. 3 and 4, the cell stack portion N
In C, the wind tunnel 13 having one side opening is connected to the side surface on the installation side of the oxygen-containing gas flow path inlet si in an airtight state so as to face the opening, and the oxygen-containing gas flow path outlet so and the fuel gas are connected. A wind tunnel 14 having an opening on one side is connected to the side surface on the installation side of the flow path outlet fo in an airtight state so as to face the opening. Therefore, the oxygen-containing gas supply unit Ks communicating the inside of the wind tunnel 13 with each of the oxygen-containing gas flow path inlets si.
In addition, the gas discharge part H serving as both the oxygen-containing gas discharge part Hs communicating with the oxygen-containing gas flow path outlets so inside the wind tunnel 14 and the fuel gas discharge part Hf communicating with the fuel gas flow path outlets fo respectively. There is. The gas discharge part H also functions as a combustion chamber that burns the exhaust oxygen-containing gas discharged from each oxygen-containing gas flow path outlet so and the exhaust fuel gas discharged from each fuel gas flow path outlet fo. .

The cell assembly U is constructed as described above.

Next, with reference to FIGS. 5 to 7, a specific structure of the fuel cell constructed by providing the cell assembly U constructed as described above inside the box-shaped body 31 will be described.

On the bottom portion 31B of the box-shaped body 31, the cell assembly U is attached.
Are provided with four mounting portions 40, and the cell assembly U is mounted on the four mounting portions 40 with the stacking direction thereof aligned with the vertical direction. . Box-shaped body 31
Is made of metal such as stainless steel.

A heat insulating material 32 is provided so as to surround the cell assembly U. Further, in the heat insulating material 32, the void portion 33 is formed so as to face the fuel gas flow path inlets fi in the cell assembly U and communicate with the through holes 31C formed in the bottom portion 31B of the box-shaped body 31. There is. The void portion 33 is made to function as the fuel gas supply portion Kf that communicates with each of the fuel gas flow path inlets fi. Further, the fuel gas supply pipe 34 is provided in the through hole 31C.
Are connected for communication. The heat insulating material 32 is made of a material having excellent heat resistance and electrical insulation, for example, a ceramic material.

One end of the inner oxygen-containing gas supply pipe 35 is
It is connected to the wind tunnel 13 in a state of communicating with the oxygen-containing gas supply unit Ks, and the other end thereof is connected to the outer oxygen-containing gas supply pipe 36 via the communication connection unit 50. Further, one end of the inner exhaust pipe 37 is connected to the discharge part H and the wind tunnel 1
4 and the other end is connected to the outer exhaust pipe 38 via the communication connecting portion 50. Communication connection part 50
Is an inner oxygen-containing gas supply pipe 35 and an outer oxygen-containing gas supply pipe 36 with the inside of the box-like body 31 kept airtight.
And the inner exhaust pipe 37 and the outer exhaust pipe 38 are connected in a communicating state. Inner oxygen-containing gas supply pipe 3
5 and the inner exhaust pipe 37 are made of a material having excellent heat resistance and electrical insulation, for example, a ceramic material, and the outer oxygen-containing gas supply pipe 36 and the outer exhaust pipe 38 are made of metal such as stainless steel.

The ends of the rod-like members 21 of the terminal portion 20 provided at the upper end and the lower end of the cell laminated portion NC are the airtight penetrating portions 6.
The box-shaped body 3 in a state in which the inside of the box-shaped body 31 is kept airtight via 0 and is electrically insulated from the box-shaped body 31.
It penetrates to the outside of 1. A lead wire 39 for extracting electric power is connected to each penetrating end of each rod-shaped body 21.

That is, the oxygen-containing gas S is supplied to the oxygen-containing gas flow passage s of each cell C through the outer oxygen-containing gas supply pipe 36, the inner oxygen-containing gas supply pipe 35 and the oxygen-containing gas supply section Ks, and The fuel gas F is supplied to the fuel gas supply pipe 3
4 and the fuel gas supply unit Kf to supply the fuel gas flow path f of each cell C, and the electric power generated in the cell stacking unit NC by the oxygen-containing gas and the fuel gas is taken out from the upper and lower terminal units 20, In addition, the exhausted oxygen-containing gas S'exhausted from each oxygen-containing gas flow path s and the exhausted fuel gas F'exhausted from each fuel gas flow path f are combusted in the gas exhaust portion H to generate combustion heat. With this, the cell stack portion NC is heated and the combustion exhaust gas of the exhaust oxygen-containing gas and the exhaust fuel gas is exhausted to the outside through the inner exhaust pipe 37 and the outer exhaust pipe 38.

Next, the mounting portion 40 will be described with reference to FIG. The mounting portion 40 is the bottom portion 31 of the box-shaped body 31.
A bolt 42 that is inserted into the through hole 41 formed in B from the outside in an airtight state and is fixed to the bottom portion 31B by welding or the like.
And a nut member 43 screwed to the bolt 42, and a tubular body 44 mounted on the nut member 43. Then, the cell aggregate U is placed on the tubular bodies 44 of each of the four placing portions 40. The nut member 43
The mounting height and the inclination of the cell assembly U are adjusted by each. The tubular body 44 is made of a material having excellent heat resistance and electrical insulation, for example, a ceramic material.

Next, the communication connecting portion 50 will be described with reference to FIG.

A cylindrical body 52 having a collar portion 52A is formed in a through hole 51 formed in a bottom portion 31B of the box-shaped body 31, and an inner peripheral portion of the through hole 51 and an outer peripheral portion of the cylindrical body 52 are hermetically sealed. It is inserted from the inside of the box-shaped body 31 and fixed to the bottom portion 31B. The cylindrical body 52, the bellows-shaped cylindrical body 53 that is deformable in the axial direction and the radial direction, the cylindrical body 54, and the outer oxygen-containing gas supply pipe 36 (or the outer exhaust pipe 38) are connected in the order of description. The inner oxygen-containing gas supply pipe 35 (or the inner exhaust pipe 37) is inserted into the cylindrical body 52, the bellows-shaped cylindrical body 53, and the cylindrical body 54 so as to be movable in the axial direction and the radial direction. An elastic annular seal member 55 is arranged between the inner peripheral portion of the cylindrical body 54 and the outer peripheral portion of the inner oxygen-containing gas supply pipe 35 (or the inner exhaust pipe 37).

Therefore, the box-shaped body 31, the inner oxygen-containing gas supply pipe 35 (or the inner exhaust pipe 37) and the outer oxygen-containing gas supply pipe 36 are accompanied by the temperature rise during the operation of the fuel cell.
(Or, the elastic deformation of the bellows-shaped cylindrical body 53 and the annular seal member 55 avoids the occurrence of stress due to the difference in thermal expansion between the outer exhaust pipes 38). That is, the cylindrical body 52, the bellows-shaped cylindrical body 53, the cylindrical body 54, and the annular seal member 55 form the communication connection portion 50. The cylindrical body 52, the bellows-shaped cylindrical body 53, and the cylindrical body 54 are made of metal such as stainless steel, and the annular seal member 55 is made of a material having heat resistance and electrical insulation, for example, silicon rubber.

Next, based on FIG. 10, the airtight penetrating portion 60.
Will be added. Incidentally, FIG. 10 shows the cell stack NC
Although the airtight penetrating portion 60 is shown for the terminal portion 20 provided at the lower end portion of the above, the terminal portion 20 provided at the upper end portion of the cell stacking portion NC has the same configuration.

A bottomed cylindrical body 62 having a through hole 62A at the bottom and an internal thread portion at the inner peripheral portion thereof is inserted into the through hole 61 formed at the bottom 31B of the box-shaped body 31. The peripheral portion and the outer peripheral portion of the cylindrical body 62 are hermetically inserted and fixed to the box-shaped body 31. A cylindrical body 63 having a large-diameter portion 63A at the axial center and a small-diameter portion 63B at both ends in the axial direction, and the small-diameter portion 63B are fitted in the through hole 62A of the bottomed cylindrical body 62 in an airtight state. As a result, it is arranged inside the bottomed cylindrical body 62. Cylindrical body 64 in which a male screw portion that is screwed into the female screw portion of the bottomed cylindrical body 62 is formed on the outer peripheral portion
Is threadedly attached to the female threaded portion of the bottomed cylindrical body 62, with an annular seal member 65 having elasticity interposed between the end surface and the end surface of the large diameter portion 63A of the cylindrical body 63, Therefore, the bottomed cylindrical body 62, the cylindrical body 63, and the cylindrical body 64 are integrally fixed. The rod-shaped body 21 is inserted into the cylindrical body 63 and the cylindrical body 64 so as to be movable in the axial direction and the radial direction. Then, an annular seal member 66 having elasticity is provided between the inner peripheral portion of the cylindrical body 63 and the outer peripheral portion of the rod-shaped body 21.

Therefore, as the temperature rises during the operation of the fuel cell, stress is generated due to the difference in thermal expansion between the box-shaped body 31 and the rod-shaped body 21 due to the elastic deformation of the annular seal member 66. Has been avoided by. That is, the bottomed cylindrical body 62, the cylindrical body 63, the cylindrical body 64, and the annular seal members 65 and 66 form the airtight penetrating portion 60. Bottomed cylindrical body 62
And the cylindrical body 64 is made of metal, the cylindrical body 63 is made of an electrically insulating material such as a ceramic material, and the annular sealing members 65 and 66 are made of a heat resistant and electrically insulating material such as silicon rubber. Consists of.

[Other Embodiments] Next, other embodiments will be listed. In the above embodiment, the heat insulating material 32 is attached to the fuel gas supply unit Kf.
However, the heat insulating material 32 may be provided with the oxygen-containing gas supply unit Ks or the gas discharge unit H.

The heat insulator 32 may be formed of a material that allows gas to flow therethrough, for example, a porous ceramic material or glass wool. In this case, it is not necessary to form the void 33 for functioning as the fuel gas supply portion Kf in the heat insulating material 32 as in the above embodiment.

As shown in FIGS. 11 and 12, in the cell assembly U, the oxygen-containing gas supply portion Ks communicating with the inlets si of the oxygen-containing gas flow passage s and the outlet so of the oxygen-containing gas flow passage s, respectively. An oxygen-containing gas discharge portion Hs, a fuel gas supply portion Kf that communicates with each of the inlets fi of the fuel gas passage f, and a fuel gas discharge portion Hf that communicates with each of the outlet fo of the fuel gas passage f. It may be provided separately. in this case,
As in the above embodiment, the recess 7A is not formed in the third columnar body 7, and the flow path inlet forming member 11 is not provided. Therefore,
One of an opening formed between the first columnar bodies 5 and 5 adjacent to each other in the stacking direction of the cells C and an opening formed between the second columnar bodies 6 and 6 adjacent to each other in the stacking direction, The fuel gas flow path inlet fi is defined as the fuel gas flow path outlet fo. Then, the oxygen-containing gas supply unit Ks and the oxygen-containing gas discharge unit H
s, the fuel gas supply unit Kf, and the fuel gas discharge unit Hf are provided in the heat insulator 32. In the figure, 71 is a wind tunnel for forming the oxygen-containing gas supply section Ks, 72 is a wind tunnel for forming the oxygen-containing gas discharge section Hs, and 73 is a wind for forming the fuel gas discharge section Hf. Show the torso. Reference numeral 74 is an inner oxygen-containing gas supply pipe, 75 is an inner oxygen-containing gas exhaust pipe, and 76 is an inner fuel gas exhaust pipe. Although not shown, the inner oxygen-containing gas supply pipe 74,
Inner oxygen-containing gas exhaust pipe 75 and inner fuel gas exhaust pipe 7
Each of the 6 connects to the outer oxygen-containing gas supply pipe, the outer oxygen-containing gas exhaust pipe, and the outer fuel gas exhaust pipe by the same communication connection portion 50 as in the above embodiment. Although not shown, the fuel gas supply unit Kf is provided in the heat insulator 31.

Further, in the embodiment shown in FIGS. 11 and 12, although not shown, a wind tunnel for forming the fuel gas supply portion Kf is connected to a side surface of the cell stack NC on the fuel gas flow path inlet fi installation side. You may. In this case,
It is not necessary to provide the heat insulator 31 with the fuel gas supply unit Kf.

In the above embodiment, the conductive separator 4
Although the case where the cell C is configured by attaching to the side of the three-layer plate facing the oxygen electrode 2 is illustrated, as shown in FIGS. 13 and 14, the same conductive separator 4 as in the above-described embodiment is provided. The cell C may be formed by attaching the layer plate on the side facing the fuel electrode 3 in the same configuration as in the above embodiment. in this case,
A plurality of groove-shaped fuel gas flow paths f are formed between a pair of strip-shaped protrusions 4b of the conductive separator 4, and a plurality of cells C are arranged in parallel in a stacked state in a state of being electrically connected in series. In the NC, an oxygen-containing gas flow channel s is provided between adjacent cells C and C.

In the figure, 81 is a wind tunnel for forming the fuel gas supply section Kf, 82 is a wind tunnel for forming the gas discharge section H, 83 is an inner fuel gas supply pipe, and 84 is an inner exhaust pipe. Indicates. Although not shown, the inner fuel gas supply pipe 83 and the inner exhaust pipe 84 are communicatively connected to the outer fuel gas supply pipe and the outer exhaust pipe at the same communicative connection portion 50 as in the above embodiment. Although not shown, the oxygen-containing gas supply unit K
s is provided in the heat insulator 31.

The specific configuration for forming the cell stacking portion NC by juxtaposing a plurality of cells C in a stacked state in a state where they are electrically connected in series is not limited to the above embodiment, and can be changed. Is.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a fuel cell.

FIG. 2 is an exploded perspective view of a cell stack portion of a fuel cell.

FIG. 3 is a side sectional view of a cell assembly of a fuel cell.

FIG. 4 is a view on arrow EE in FIG.

FIG. 5 is a side sectional view of a fuel cell.

FIG. 6 is a view on arrow in FIG.

FIG. 7 is a view as seen from the arrow in FIG.

FIG. 8 is a vertical sectional view of a mounting portion of a fuel cell.

FIG. 9 is a vertical sectional view of a communication connection portion of a fuel cell.

FIG. 10 is a vertical sectional view of an airtight penetration portion of a fuel cell.

FIG. 11 is a side sectional view of a cell assembly of a fuel cell according to another embodiment.

FIG. 12 is a view as seen from the direction of the arrows in FIG.

FIG. 13 is a side sectional view of a cell assembly of a fuel cell according to another embodiment.

FIG. 14 is a view on arrow in FIG.

[Explanation of symbols]

 1 plate-like electrolyte layer 2 oxygen electrode 3 fuel electrode 31 box-shaped body 32 heat insulating body f fuel gas flow channel fi fuel gas flow channel inlet fo fuel gas flow channel outlet s oxygen-containing gas flow channel si oxygen-containing gas flow channel inlet so oxygen Contained gas flow path outlet C cell H gas discharge part Hf fuel gas discharge part Hs oxygen-containing gas discharge part Kf fuel gas supply part Ks oxygen-containing gas supply part U cell assembly

Claims (4)

[Claims] 1. A plate-like electrolyte layer (1) having an oxygen electrode (2) on one surface and a fuel electrode (3) on the other surface, and oxygen on the side facing the oxygen electrode (2). A plurality of cells (C) of a fuel cell having a containing gas channel (s) and having a fuel gas channel (f) on the side facing the fuel electrode (3) are juxtaposed in a stacked state, and the oxygen containing gas is provided. Oxygen-containing gas supply unit (Ks) communicating with each inlet (si) of the flow path (s)
And an oxygen-containing gas discharge part (Hs) communicating with each outlet (so) of the oxygen-containing gas flow channel (s) and a fuel gas supply communicating with each inlet (fi) of the fuel gas flow channel (f). Part (Kf) and the outlet (fo) of the fuel gas flow path (f)
A fuel cell in which a fuel gas discharge part (Hf) communicating with each other is provided to form a cell assembly (U), and the cell assembly (U) is provided inside the box-shaped body (31). A fuel cell provided with a heat insulating body (32) surrounding the cell assembly (U). 2. The heat insulator (32) comprises the oxygen-containing gas supply section (Ks), the oxygen-containing gas discharge section (Hs),
The fuel cell according to claim 1, further comprising one of the fuel gas supply unit (Kf) and the fuel gas discharge unit (Hf). 3. The discharged oxygen-containing gas discharged from the oxygen-containing gas flow path outlet (so) and the fuel gas flow path in the oxygen-containing gas discharge part (Hs) and the fuel gas discharge part (Hf). The heat insulator (32) is composed of one gas discharge part (H) that functions as a combustion chamber for burning the exhaust fuel gas discharged from the outlet (fo), and the heat insulator (32) is the oxygen-containing gas supply part (Ks). The fuel cell according to claim 1, further comprising one of a fuel gas supply unit (Kf) and the gas discharge unit (H). 4. The fuel cell according to claim 2, wherein the heat insulator (32) is made of a porous material that allows gas to flow therethrough.