JP2013225422A - Fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell which deforms according to displacement of a gap between a cell body and a connector thereby relaxing stress and maintaining good electric connectivity in long term use.SOLUTION: A fuel cell 1 includes: a cell body 3 where electrodes 14, 15 are respectively formed on front and rear surfaces of an electrolyte body 2; conductive connectors 12, 13 which are disposed facing the electrodes of the cell body; and collector members 18, 19 disposed between the electrodes and the connectors and connecting the electrodes with the connectors. For example, one of the collector members 19 includes: a conductive sheet member 19a that is disposed between the connector 13 and the electrode 15 so that one surface faces the connector 13 and the other surface faces the electrode 15; a connector side collector 19b disposed on one surface of the sheet member and connecting the sheet member with the connector; and an electrode side collector 19c disposed on the other surface of the sheet member and connecting the sheet member with the electrode. The collector side collector 19b and the electrode side collector 19c are disposed so as not to overlap with each other when viewed along a thickness direction of the cell body 3.

Description

  The present invention relates to a fuel cell in which two electrodes are provided on the front and back surfaces of a plate-shaped electrolyte body, and a reactive gas is supplied to each electrode to generate electric power.

  A general fuel cell includes a cell body in which electrodes are formed on the front and back surfaces of a plate-shaped electrolyte body, and a pair of conductive connectors disposed respectively facing the electrodes on the front and back surfaces of the cell body. And a current collecting member that is disposed between the electrode of the cell main body and the connector to electrically connect the two (see Patent Document 1).

  In such a fuel cell, a wide and narrow displacement may occur in the distance between the cell body and the connector due to a temperature cycle, a change in the pressure of the reaction gas, and the like. Therefore, the current collecting member that electrically connects the cell body and the connector has various structures so that the cell body and the connector can be stably connected by appropriately deforming against the displacement of such a distance to relieve the stress. Is considered.

  As one example, as shown in FIG. 15, semi-elliptical protrusions 500, 500... Contacting the cell main body (not shown) and the connector (not shown) have different vertical positions and orientations. A current collecting member 700 that is formed in plural in 600 and thus combines the deformation of the protrusion 500 itself with the deformation of the base member 600 that supports the protrusion 500 is described, for example, in FIG. .

JP 2008-147021 A

  However, since the current collecting member 700 shown in FIG. 15 is formed of a single material and does not have sufficient ability to relieve stress, when the current collecting member 700 is displaced in a direction in which the distance between the cell body and the connector is increased, Residual stress is easily transmitted to the interface between the protrusion 500 and the cell body, which may cause a gap. Further, when the distance between the cell main body and the connector is reduced, the residual stress is easily transmitted to the interface between the protrusion 500 of the current collecting member 700 and the cell main body, and the cell main body may be destroyed.

  The present invention has been made in view of the above, and its purpose is to deform in accordance with the displacement of the distance between the cell body and the connector, thus relaxing the stress and maintaining good electrical connectivity even in long-term use. It is to provide a possible fuel cell.

In order to achieve the above object, the present invention as described in claim 1,
A cell body in which electrodes are respectively formed on the front and back surfaces of the plate-like electrolyte body;
A connector having electrical conductivity disposed opposite to the electrode of the cell body;
A fuel cell that is disposed between the electrode and the connector and electrically connects the electrode and the connector;
The current collecting member is
A sheet-like sheet member provided between the connector and the electrode such that one surface faces the connector and the other surface faces the electrode;
A connector-side current collector that is disposed on the one surface of the sheet member and electrically connects the sheet member and the connector;
An electrode-side current collector that is disposed on the other surface of the sheet member and electrically connects the sheet member and the electrode;
Provided is a fuel cell arranged so that the connector-side current collector and the electrode-side current collector do not overlap when viewed along the thickness direction of the cell body.

  In addition, as described in claim 2, the sheet member is configured of a member that is more easily deformed than any of the connector-side current collector and the electrode-side current collector. A fuel cell is provided.

  Moreover, as described in claim 3, when viewed along the thickness direction of the cell body, the distance (L) between the connector-side current collector and the electrode-side current collector is the thickness of the cell body. The fuel according to claim 2, wherein the fuel is set to be larger than both the thickness (H1) of the connector-side current collector in the direction and the thickness (H2) of the electrode-side current collector in the thickness direction of the cell body. Provide batteries.

  In addition, as described in claim 4, a position that overlaps with the connector-side current collector when viewed along the thickness direction of the cell body between the cell body and the sheet member arranged to face each other. The fuel cell according to any one of claims 1 to 3, wherein a first interposed member is disposed in the fuel cell.

  In addition, as described in claim 5, between the connector and the sheet member disposed to face each other, when viewed along the thickness direction of the cell body, the electrode-side current collector is overlapped. The fuel cell according to any one of claims 1 to 4, wherein a second interposed member is disposed.

  In addition, as described in claim 6, the fuel cell according to any one of claims 1 to 5, wherein the sheet member has a structure having a vent hole.

  Moreover, as described in claim 7, the fuel cell according to claim 6, wherein the sheet member is a mesh.

  The fuel cell according to any one of claims 1 to 7, wherein the electrode-side current collector is made of at least one of Ni cermet, felt, or non-woven fabric. To do.

Moreover, as described in claim 9,
The connector has a plate shape forming two main surfaces,
Two adjacent cell bodies are respectively disposed on two main surface sides of the connector,
When one of the two cell bodies is a first cell body and the other is a second cell body,
A first current collecting member that electrically connects the first cell body and the connector is disposed on one main surface of the connector on the first cell body side,
A second current collecting member for electrically connecting the second cell main body and the connector is disposed on the other main surface of the connector on the second cell main body side,
When viewed along the thickness direction of the cell body, the electrode-side current collector of the first current collector and the connector-side current collector of the second current collector are arranged so as not to overlap. A fuel cell according to any one of claims 1 to 8 is provided.

Moreover, as described in claim 10,
A plate-like connector having first and second main surfaces;
A first cell main body provided with first and second electrodes on both sides of the plate-shaped first electrolyte body, the first electrode being disposed toward the first main surface of the connector;
A second cell main body provided with third and fourth electrodes on both sides of the plate-like second electrolyte body, respectively, the fourth electrode being arranged toward the second main surface of the connector;
A contact portion formed on the first main surface of the connector and in contact with the surface of the first electrode of the first cell body;
A current collecting member disposed between the fourth electrode of the second cell main body and the second main surface of the connector, and electrically connecting the fourth electrode and the connector;
A fuel cell comprising:
The current collecting member is
A sheet-like sheet member having electrical conductivity, disposed between the connector and the fourth electrode such that one surface faces the connector and the other surface faces the fourth electrode;
A connector-side current collector that is disposed on the one surface of the sheet member and electrically connects the sheet member and the connector;
An electrode-side current collector disposed on the other surface of the sheet member and electrically connecting the sheet member and the fourth electrode;
When viewed along the thickness direction of the connector,
Provided is a fuel cell arranged such that the connector-side current collector and the electrode-side current collector, and the connector-side current collector and the contact portion do not overlap.

  In the fuel cell according to claim 1, since the current collecting member has a structure in which three members of the sheet member, the connector-side current collector, and the electrode-side current collector are combined, the connector-side current collector and the electrode side The current collector is formed of a material having elasticity in the thickness direction of the cell body, and further, the sheet member that supports them is formed of a material that can be deformed in the surface direction. It is possible to enhance the stress relaxation performance when a wide and narrow displacement occurs in the distance between the cell body and the connector due to the temperature cycle and the change in the pressure of the reaction gas.

  In addition, as described in claim 2, if the sheet member is formed of a member that is more easily deformed than either the connector-side current collector or the electrode-side current collector, the connector-side current collector can be applied to a small displacement. In addition, it is possible to respond quickly by deformation of the sheet member without depending on deformation of the electrode-side current collector.

  Further, as defined in claim 3, when viewed along the thickness direction of the cell body, the distance (L) between the connector-side current collector and the electrode-side current collector, in other words, the thickness direction of the cell body. The distance (L) between when the connector-side current collector and the electrode-side current collector are projected onto the cell body or electrode, the thickness (H1) of the connector-side current collector in the thickness direction of the cell body and the cell body By setting the thickness larger than any of the thicknesses (H2) of the electrode-side current collector in the thickness direction, the buffering action of the sheet member is increased, and the width that can be quickly handled by deformation of the sheet member is widened.

  According to a fourth aspect of the present invention, between the cell body and the sheet member arranged to face each other, when viewed along the thickness direction of the cell body, the first intervening position overlaps with the connector-side current collector. By disposing the member, even if a material that can be seized on the electrode of the cell body is selected as the material of the sheet member, seizure can be prevented by the interposition of the first interposing member. Accordingly, the material selection range of the sheet member is widened.

  Further, as described in claim 5, the second interposition member is located at a position overlapping with the electrode-side current collector when viewed along the thickness direction of the cell body between the connector and the sheet member arranged to face each other. Even when a material that can be seized onto the connector is selected as the material of the sheet member, seizure can be prevented by the interposition of the second intervening member. Accordingly, the material selection range of the sheet member is widened.

  In addition, since the reactive gas can pass through the sheet member and come into contact with the electrode by forming the sheet member with a material having a vent hole as described in claim 6, the sheet member is enlarged and firmly fixed. The side current collector and the connector side current collector can be supported. As such a sheet member, there is a mesh as specifically described in claim 7.

  Further, as described in claim 8, if the electrode-side current collector is made of a material having air permeability such as Ni cermet, felt, or nonwoven fabric, the electrode-side current collector is enlarged and the contact surface with the electrode is increased. Can be increased.

  In the fuel cell according to claim 9, the current collecting member according to claims 1 to 8 is arranged between all the electrodes and the connector. By disposing the electrode-side current collector of the current member and the connector-side current collector of the second current collector member so as not to overlap, all the electrode-side current collectors and the connector-side current collectors of one connector They are not lined up symmetrically on the front and back (see FIG. 11). As a result, the current collecting members hardly affect each other via the cell body or the connector, and the displacement of each element is easily absorbed.

  Further, in the fuel cell according to claim 10, as in the fuel cell according to claim 1, the current collecting member has a structure in which three members of a sheet member, a connector-side current collector, and an electrode-side current collector are combined. Therefore, the connector-side current collector and the electrode-side current collector are formed of a material having elasticity in the thickness direction of the cell body, and further, the sheet member that supports them is formed of a material that can be deformed in the plane direction. Thus, the material of each member can be selected as appropriate, and the stress relaxation performance can be enhanced when a wide and narrow displacement occurs between the cell body and the connector due to the temperature cycle or the fluctuation of the pressure of the reaction gas. In addition, by arranging the connector-side current collector of the current-collecting member so as not to overlap the contact portion formed on the first main surface of the connector, the contact portion affects the deformation of the connector-side current collector. Therefore, the displacement absorbing action of the connector-side current collector is efficiently performed.

It is a disassembled perspective view of a fuel cell. It is a disassembled perspective view of the fuel cell which narrowed down decomposition parts. It is a perspective view of a fuel cell. It is a longitudinal cross-sectional view containing the partially expanded view which abbreviate | omitted the middle of the fuel cell. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is a perspective view including the partially enlarged view of a current collection member. It is a disassembled perspective view of a current collection member. It is a perspective view of the fuel cell made into the laminated body. It is a principal part expanded sectional view of the fuel cell made into the laminated body. FIG. 10 is a cross-sectional view showing a main part of a fuel cell in a stacked body according to another embodiment. It is a longitudinal cross-sectional view which showed the other form and abbreviate | omitted the middle of the fuel cell made into the laminated body. It is a disassembled perspective view of the current collection member which shows another form. It is a disassembled perspective view of the current collection member which shows another form. It is a principal part expanded sectional view of the current collection member which shows a prior art.

Currently, fuel cells are roughly classified according to the material of the electrolyte body. The polymer electrolyte fuel cell (PEFC) uses a polymer electrolyte membrane as the electrolyte, and the phosphoric acid fuel cell (PAFC) uses phosphoric acid as the electrolyte. There are four types: a molten carbonate fuel cell (MCFC) using Li-Na / K carbonate as an electrolyte, and a solid oxide fuel cell (SOFC) using a ZrO ₂ ceramic as an electrolyte, for example. . Each type has a different operating temperature (the temperature at which ions can move through the electrolyte body). At present, PEFC is at room temperature to about 90 ° C, PAFC is about 150 ° C to 200 ° C, MCFC is about 650 ° C to 700 ° C, SOFC Is about 700 ° C to 1000 ° C.

The fuel cell 1 shown in FIGS. 1 to 10 is an SOFC using, for example, a ZrO ₂ ceramic as an electrolyte body 2. The fuel cell 1 includes a cell body 3 including one electrolyte body 2, an air supply passage 4 for supplying air as one reaction gas to the fuel cell 1, and an air exhaust passage 5 for discharging the air to the outside. And a fuel supply passage 6 for supplying a fuel gas such as hydrogen as another reaction gas to the fuel cell 1 and a fuel exhaust passage 7 for discharging the fuel gas to the outside. The fuel cell 1 is a minimum unit of power generation. An actual fuel cell 100 includes a stacked body 8 in which a plurality of fuel cells 1 are stacked in series as shown in FIG. It is roughly comprised from the fixing member 9 fixed to the container, the container 10 which accommodates the laminated body 8, and the output member 11 which outputs the electric power generated with the laminated body 8. FIG.

[Fuel cell]
The fuel cell 1 has a square shape in plan view, and as shown in FIG. 1, is formed of a ferritic stainless steel having conductivity in the form of a square plate having two main surfaces (* "up" or “Lower” is based on the description in the drawing, but this is merely for convenience of description and does not mean absolute top and bottom. The same shall apply hereinafter.) And a rectangular plate having two main surfaces. An inward main surface of the connector 12 on the plate-like electrolyte body 2 and positioned substantially in the middle between the lower connector 13 formed of ferritic stainless steel having conductivity in the form and the upper and lower connectors 12, 13 ( An electrode (hereinafter also referred to as an air electrode) 14 is formed on the surface facing the lower surface), and an electrode (hereinafter also referred to as a fuel electrode) 15 on the back surface facing the inward main surface (upper surface) of the lower connector 13. Formed Inside the body 3, an air chamber 16 formed between the upper connector 12 and the air electrode 14, a fuel chamber 17 formed between the lower connector 13 and the fuel electrode 15, and the air chamber 16. A current collecting member 18 on the air electrode 14 side that is disposed and electrically connects the air electrode 14 and the upper connector 12, and a fuel electrode 15 disposed in the fuel chamber 17 and the lower connector 13 are electrically connected to each other. And a current collecting member 19 on the fuel electrode 15 side to be connected, and tightening through holes 47, 47... For passing tightening members 46a to 46d (described later) of the fixing member 9 at appropriate positions including a square corner portion. It is formed in a penetrating state.

[Electrolyte]
The electrolyte body 2 is formed in a plate shape using a LaGaO ₃ ceramic, a BaCeO ₃ ceramic, a SrCeO ₃ ceramic, a SrZrO ₃ ceramic, a CaZrO ₃ ceramic, or the like, in addition to a ZrO ₂ ceramic.

[Fuel electrode]
The material of the fuel electrode 15 is made of a metal such as Ni and Fe and a ceramic such as ZrO ₂ ceramic such as zirconia stabilized by at least one kind of rare earth elements such as Sc and Y, and CeO ₂ ceramic. A mixture with at least one of them is mentioned. The material of the fuel electrode 15 may be a metal such as Pt, Au, Ag, Pb, Ir, Ru, Rh, Ni and Fe. These metals may be only one kind, or two or more kinds of alloys. Also good. Furthermore, a mixture (including cermet) of these metals and / or alloys and at least one of each of the above ceramics may be mentioned. Moreover, the mixture etc. of metal oxides, such as Ni and Fe, and at least 1 type of each of the said ceramic are mentioned.

[Air electrode]
As the material of the air electrode 14, for example, various metals, metal oxides, metal double oxides, and the like can be used. Examples of the metal include metals such as Pt, Au, Ag, Pb, Ir, Ru, and Rh, or alloys containing two or more metals. Further, examples of the metal oxide include oxides such as La, Sr, Ce, Co, Mn and Fe (La ₂ O ₃ , SrO, Ce ₂ O ₃ , Co ₂ O ₃ , MnO ₂ and FeO). It is done. As the double oxide, a double oxide containing at least La, Pr, Sm, Sr, Ba, Co, Fe, Mn, etc. (La _1-X Sr _X CoO ₃ -based double oxide, La _1-X Sr _X FeO ₃ -based double oxide, La _1-X Sr _X Co _1-y FeO ₃ -based double oxide, La _1-X Sr _X MnO ₃ -based double oxide, Pr _1-X Ba _X CoO ₃ -based double oxide And Sm _1-X Sr _X CoO ₃ -based double oxide).

[Fuel chamber]
As shown in FIGS. 1 and 2, the fuel chamber 17 surrounds the current collecting member 19 and is installed on the upper surface of the lower connector 13. (Hereinafter also referred to as “fuel electrode insulation frame”) 21 and a fuel electrode frame 22 which is in the form of a frame and is installed on the upper surface of the fuel electrode insulation frame 21, is formed in a square room shape.

[Current collector on the fuel chamber side]
The current collecting member 19 on the fuel chamber 17 side is connected to the connector 13 so that one surface faces the connector 13 and the other surface faces the fuel electrode 15, as shown in FIGS. A conductive sheet-like sheet member 19a disposed between the fuel electrodes 15, and a sheet member 19a disposed on the surface of the sheet member 19a facing the connector 13 to electrically connect the sheet member 19a and the connector 13. A connector-side current collector 19b; and an electrode-side current collector 19c that is disposed on the surface of the sheet member 19a facing the fuel electrode 15 and electrically connects the sheet member 19a and the fuel electrode 15. Yes.

[Sheet material]
The sheet member 19a is made of, for example, Cu having a size substantially matching the inside of the fuel chamber 17, and has a mesh structure having mesh-like ventilation holes as shown in FIG. 8, or a punching structure having a large number of ventilation holes in a Cu foil. (Not shown) and has flexibility in the surface direction.

[Connector-side current collector]
The connector-side current collector 19b is a conductive porous body having moderate deformation elasticity in the thickness direction, and is formed of, for example, Ni cermet, felt, or nonwoven fabric. The connector-side current collector 19b is formed by arranging a plurality of connector-side strips 19bT, 19bT,... Elongated in the fuel gas flow direction at intervals, as shown in FIGS. It is joined to 19a.

[Electrode current collector]
The electrode-side current collector 19c is a conductive porous body having moderate deformation elasticity in the thickness direction, and is formed of, for example, Ni cermet, felt, or nonwoven fabric. As shown in FIGS. 7 and 8, the electrode-side current collector 19c is composed of a plurality of electrode-side strips 19cT, 19cT,... Elongated in the fuel gas flow direction, and the connector-side current collectors 19b, 19b. The connector strips 19bT, 19bT,... Are juxtaposed to the sheet member 19a.

By the way, when both or one of the connector-side current collector 19b and the electrode-side current collector 19c is Ni or Ni alloy, the contact surface with the connector 13 or the fuel electrode 15 in a high temperature environment during power generation. The contact surfaces are integrated by diffusion bonding. Therefore, the electrical connection by the current collecting member 19 is more stably maintained.
It is preferable to apply a NiO paste to the fuel electrode 15 to form a bonding layer. By doing so, NiO is changed to Ni by energization in H ₂ , so that the bonding property between the electrode-side current collector 19 c and the fuel electrode 15 is further improved. The bonding layer may be formed by applying a Pt paste to the fuel electrode 15.

[Connector-side current collector-Electrode-side current collector]
The connector-side current collector 19b and the electrode-side current collector 19c are arranged so as not to overlap each other when viewed along the thickness direction of the cell body 3 as described above. Specifically, when viewed along the thickness direction of the cell body 3 in FIG. 4, the distance (L) between the connector-side current collector 19 b and the electrode-side current collector 19 c is determined in the thickness direction of the cell body 3. The thickness is set to be larger than both the thickness (H1) of the connector-side current collector 19b and the thickness (H2) of the electrode-side current collector 19c in the thickness direction of the cell body 3. By doing so, the deformation region of the sheet member 19a is widened and the buffering force is increased. In addition, the sheet member 19a is more easily deformed than both the connector-side current collector 19b and the electrode-side current collector 19c, whereby the buffering force of the sheet member 19a can be preferentially applied.

  On the other hand, when the distance (L) between the connector-side current collector 19b and the electrode-side current collector 19c is larger than any of the thicknesses (H1, H2) of both the current collectors 19b, 19c, the connector-side current collector 19b There is a possibility that the sheet member 19 a pushed by the electrode contacts the fuel electrode 15 of the cell body 3, and the sheet member 19 a pushed by the electrode side current collector 19 c may come into contact with the connector 13. In this case, depending on the combination of the materials of the members in contact with each other (the sheet member 19a and the fuel electrode 15, the sheet member 19a and the connector 13), there is a possibility of sintering at a high temperature (fuel cell operating temperature range) during power generation, If sintered, the buffering action of the sheet member 19a does not function at that portion.

Therefore, in the embodiment, the sheet member 19a and the fuel electrode 15 are prevented from being seized at a position overlapping the connector-side current collector 19b when viewed along the thickness direction of the cell body 3 between the cell body 3 and the sheet member 19a. The first interposition member 20a is disposed, and between the connector 13 and the sheet member 19a, the sheet member 19a and the connector are positioned so as to overlap the electrode side current collector 19c when viewed along the thickness direction of the cell body 3. A second interposed member 20b for preventing 13 burn-in is disposed. The material of the first interposed member 20a and the second interposed member 20b may be any one of mica, alumina, vermiculite, carbon fiber, silicon carbide fiber, silica, or at least one of them as a main component. Good.
The first interposed member 20a and the second interposed member 20b preferably have a shape that can cover the entire overlapping portion. However, as long as it has a function that does not cause direct contact between the target members, The shape which covers a part may be sufficient.

[Air chamber]
As shown in FIGS. 1, 2, and 4, the air chamber 16 has a rectangular frame shape and a conductive thin metal separator 23 having the lower surface to which the electrolyte body 2 is attached. A frame-shaped air electrode gas flow path forming insulating frame (hereinafter also referred to as “air electrode insulating frame”) 24 that is installed between the separator 23 and the upper connector 12 and surrounds the current collecting member 18; Is formed into a square room.

[Current collector on the air chamber side]
The current collecting member 18 on the air chamber 16 side is in the shape of an elongated plate, is formed of a dense conductive member such as stainless steel, and the air electrode 14 on the surface of the electrolyte body 2 and the inward main surface (lower surface) of the upper connector 12. ) And a plurality of the same (in the embodiment, the same number as the electrode side current collector 19c) when viewed along the thickness direction of the cell body 3 as shown in FIG. They are arranged at overlapping positions.

  The current collecting member 18 on the air chamber 16 side may have the same structure as the current collecting member 19 on the fuel chamber 17 side. FIG. 11 is a longitudinal sectional view showing a preferred form in that case. That is, FIG. 11 shows a stack of a plurality of fuel cells 1, and a connector 12-13 having two main surfaces (the connector of the stacked body 8 shares connectors 12 and 13 that are vertically adjacent to each other as will be described later. , Such a connector is marked with “12-13.” The same applies hereinafter, with one of two adjacent cell bodies 3 being the first cell body 3/1 and the other being the second cell body 3/2. The first current collecting member 19 that electrically connects the first cell body 3/1 and the connector 12-13 to one main surface of the connector 12-13 on the first cell body 3/1 side. 2 is a second current collecting member that electrically connects the second cell body 3/2 and the connector 12-13 to the other main surface of the connector 12-13 on the second cell body 3/2 side. 18/2 is arranged and when viewed along the thickness direction of the cell body 3, 1 and the electrode side current collector 19c of the current collecting member 19/1, are arranged such that the second current collecting member 18/2 connector side current collector 19b do not overlap. This state is a state in which the current collecting member 19 is moved in parallel for each layer, and as shown in FIG. 11, all the connector-side current collectors 19b and the electrode-side current collectors 19c are connected via the sheet members 19a. Since the buffer space S corresponds, the current collecting members 19/1 and 18/2 hardly affect each other via the cell body 3 or the connector 12-13, and the displacement of each element is easily absorbed. .

Further, the current collecting member 18 on the air chamber 16 side may be changed to a contact portion 180 integrated with the connector 12 (13). FIG. 12 is a longitudinal sectional view showing the form. That is, FIG. 12 shows a stack of a plurality of fuel cells 1, which are respectively provided on both sides of a plate-like connector 12-13 having first and second main surfaces and a plate-like first electrolyte body 2/1. First and second electrodes (hereinafter referred to as a first air electrode 14/1 and a second fuel electrode 15/2) are provided, and the first air electrode 14/1 is connected to the first electrode 12-13 of the connector 12-13. 3rd and 4th electrodes (hereinafter referred to as third air electrode 14) on both sides of the first cell main body 3/1 arranged toward the main surface of the first cell body 3 and the plate-like second electrolyte body 2/2, respectively. / 3, fourth fuel electrode 15/4), and the fourth fuel electrode 15/4 is arranged with the fourth fuel electrode 15/4 facing the second main surface of the connector 12-13. A contact portion 180 formed on the first main surface of the connector 12-13 and in contact with the surface of the first air electrode 14/1 of the first cell body 3/1; The fourth fuel electrode 15/4 of the second cell body 3/2 and the second main surface of the connector 12-13 are disposed between the fourth fuel electrode 15/4 and the connector 12-13. And a current collecting member 19 to be electrically connected.
The current collecting member 19 includes the connector 12-13 and the fourth fuel electrode 15/4 so that one surface faces the connector 12-13 and the other surface faces the fourth fuel electrode 15/4. A sheet-like sheet member 19a provided between the sheet member 19a and a connector-side current collector 19b disposed on one surface of the sheet member 19a to electrically connect the sheet member 19a and the connector 12-13; And an electrode-side current collector 19c that is disposed on the other surface of the sheet member 19a and electrically connects the sheet member 19a and the fourth fuel electrode 15.
Further, when viewed along the thickness direction of the connector 12-13, each of the elements does not overlap the connector side current collector 19b and the electrode side current collector 19c, and the connector side current collector 19b and the contact portion 180. Is arranged.
In such a configuration, since the contact portion 180 integral with the connector 12-13 hardly deforms, the displacement is absorbed exclusively by the current collecting member 18 on the fuel chamber 17 side.

  As described above, the fuel cell 1 includes a fuel chamber by combining the lower connector 13, the fuel electrode insulating frame 21, the fuel electrode frame 22, the separator 23, the air electrode insulating frame 24, and the upper connector 12. 17 and the air chamber 16 are formed, the fuel chamber 17 and the air chamber 16 are separated from each other by the electrolyte body 2, and the fuel electrode 15 side and the air electrode are further separated by the fuel electrode insulating frame 21 and the air electrode insulating frame 24. The 14 side is electrically insulated.

  The fuel cell 1 also includes an air supply unit 25 including an air supply channel 4 that supplies air into the air chamber 16, and an air exhaust unit including an air exhaust channel 5 that discharges air from the air chamber 16 to the outside. 26, a fuel supply unit 27 including a fuel supply channel 6 for supplying fuel gas into the fuel chamber 17, and a fuel exhaust unit 28 including a fuel exhaust channel 7 for discharging the fuel gas from the fuel chamber 17 to the outside. It is equipped with.

[Air supply section]
The air supply unit 25 is provided on the air electrode insulating frame 24 so as to communicate with the air supply through hole 29 opened in the vertical direction on one side of the square fuel cell 1 and close to the corner. An air supply communication chamber 30 having a long hole shape, and an air supply communication section 32 formed by recessing a plurality of upper surfaces of partition walls 31 partitioning between the air supply communication chamber 30 and the air chamber 16 at equal intervals; And the air supply passage 4 for supplying air to the air supply communication chamber 30 from the outside through the air supply through hole 29.

[Air exhaust part]
The air exhaust unit 26 has an air exhaust hole 33 opened in the vertical direction at a position near one side corner on the opposite side of the air supply unit 25 of the fuel cell 1, and an air electrode so as to communicate with the air exhaust hole 33. An air exhaust communication chamber 34 formed in the insulating frame 24 and formed by recessing a plurality of upper surfaces of partition walls 35 partitioning the air exhaust communication chamber 34 and the air chamber 16 at equal intervals. 36 and the tubular air exhaust passage 5 which is inserted into the air exhaust passage 33 and exhausts air from the air exhaust communication chamber 34 to the outside.

[Fuel supply section]
The fuel supply unit 27 has a fuel supply through hole 37 opened in the vertical direction on the same side as the air supply unit 25 of the square fuel cell 1 and at a position near the corner opposite to the air supply through hole 29; A plurality of upper surface of a long-hole-shaped fuel supply communication chamber 38 formed in the fuel electrode insulating frame 21 so as to communicate with the fuel supply through hole 37 and a partition wall 39 partitioning between the fuel supply communication chamber 38 and the fuel chamber 17 are provided. A fuel supply communication section 40 formed by being recessed at equal intervals; a tubular fuel supply flow path 6 that is inserted into the fuel supply through hole 37 and supplies fuel gas from the outside to the fuel supply communication chamber 38; It has.

[Fuel exhaust part]
The fuel exhaust unit 28 has a fuel exhaust hole 41 opened in the vertical direction at a position near the corner on the opposite side of the fuel supply unit 27 of the fuel cell 1, and a fuel electrode so as to communicate with the fuel exhaust hole 41. A long-hole fuel exhaust communication chamber 42 provided in the insulating frame 21, and a fuel exhaust communication portion formed by recessing a plurality of upper surfaces of partition walls 43 partitioning between the fuel exhaust communication chamber 42 and the fuel chamber 17 at equal intervals. 44 and a tubular fuel exhaust passage 7 that is inserted into the fuel exhaust passage 41 and discharges fuel gas from the fuel exhaust communication chamber 42 to the outside.

[Laminate]
As described above, the fuel cell 1 is the minimum unit of power generation and can generate power alone. In practice, however, a plurality of fuel cells 1 are stacked in series as shown in FIG. Power is generated in the state of the laminated body 8. When a plurality of fuel cells 1 are stacked, the upper connector 12 of the fuel cell 1 positioned below and the lower connector 13 of the fuel cell 1 mounted thereon are integrated with the upper and lower fuel cells 1, 1. Share with each other.
The fixing member 9 includes a pair of end plates 45a and 45b sandwiching the upper and lower sides of the laminated body 8, the end plates 45a and 45b and the laminated body 8 at the corner holes (not shown) of the end plates 45a and 45b, and the laminated body 8. 6 tightening members 46a to 46f that are tightened with nuts through bolts to the tightening through holes 47. The material of the fastening members 46a to 46f is, for example, Inconel 601.

  The air supply flow path 4 is attached to the stacked body 8 of the fuel cell 1 so as to penetrate the through holes (not shown) of the end plates 45a and 45b and the air supply through holes 29 vertically. Air is supplied to the air supply communication chamber 30 through the horizontal hole 48 by closing the end of the tubular flow path and providing the horizontal hole 48 corresponding to each of the air supply communication chambers 30 as shown in FIG. It has come to be.

  Similarly, the air exhaust passage 5 takes in air from the lateral hole 49 corresponding to each air exhaust communication chamber 34 and discharges it to the outside, and the fuel supply passage 6 is provided for each fuel supply communication chamber 38 as shown in FIG. The fuel gas is supplied from the lateral hole 50 corresponding to the fuel exhaust, and the fuel exhaust passage 7 takes in the fuel gas from the lateral hole 51 corresponding to each fuel exhaust communication chamber 42 and discharges it to the outside.

[container]
The container 10 for storing the laminated body 8 has a heat-resistant and sealed structure, and as shown in FIG. 9, the two halves 53a and 53b having flanges 52a and 52b at the openings are joined to face each other. Is. The bolts of the fastening members 46 a to 46 f protrude from the top of the container 10, and a nut 54 is screwed into the protruding portions of the fastening members 46 a to 46 f to fix the laminated body 8 in the container 10. Further, the air supply flow path 4, the air exhaust flow path 5, the fuel supply flow path 6 and the fuel exhaust flow path 7 also protrude outside from the top of the container 10, and a supply source of air or fuel gas, etc. Is connected.

[Output member]
The output member 11 that outputs electricity generated by the fuel cell 1 is the fastening members 46a to 46d and the end plates 45a and 45b located at the corners of the laminate 8, and a pair of fastening members 46a that face diagonally. , 46c are electrically connected to the upper end plate 45a, which is a positive electrode, and the other pair of fastening members 46b, 46d are electrically connected to the lower end plate 45b, which is a negative electrode. Of course, the fastening members 46a and 46d connected to the positive electrode and the fastening members 46b and 46c connected to the negative electrode interpose an insulating washer 55 (see FIG. 9) with respect to the end plate 45a (45b) of the other electrode, and are laminated. The body 8 is insulated by providing a gap between the body 8 and the tightening through hole 47. Therefore, the fastening members 46a and 46c of the fixing member 9 also function as positive output terminals connected to the upper end plate 45a, and the other fastening members 46b and 46d are negative electrodes connected to the lower end plate 45b. Also functions as an output terminal.

[Power generation]
When air is supplied to the air supply channel 4 of the fuel cell 1, the air flows from the upper side to the lower side in FIG. 5, and the upper air supply channel 4, the air supply communication chamber 30, and the air supply communication unit 32 is supplied to the air chamber 16 through the air supply unit 25, and passes through the gas flow path 56 between the current collecting members 18 of the air chamber 16. Further, the air exhaust communication unit 36 and the air exhaust communication chamber 34 and the air exhaust passage 26 composed of the air exhaust passage 5 and discharged to the outside.

  At the same time, when, for example, hydrogen is supplied to the fuel supply channel 6 of the fuel cell 1 as the fuel gas, the fuel gas flows from the upper side to the lower side in FIG. 6, and the upper fuel supply channel 6, the fuel supply communication chamber 38, Then, the fuel is supplied to the fuel chamber 17 through the fuel supply unit 27 including the fuel supply communication unit 40, passes through the gas flow path 57 of the current collecting member 19 of the fuel chamber 17 while being diffused, and further to the fuel exhaust communication unit 44. Then, the fuel is exhausted to the outside through the fuel exhaust part 28 including the fuel exhaust communication chamber 42 and the fuel exhaust passage 7.

  When the temperature in the container 10 is raised to 700 ° C. to 1000 ° C. while supplying and exhausting such air and fuel gas, the air and fuel gas are passed through the air electrode 14, the electrolyte body 2, and the fuel electrode 15. Therefore, direct current electric energy is generated with the air electrode 14 as a positive electrode and the fuel electrode 15 as a negative electrode. In addition, since the principle which an electrical energy generate | occur | produces in the fuel cell 3 is known, description is abbreviate | omitted.

  As described above, the air electrode 14 is electrically connected to the upper connector 12 via the current collecting member 18, while the fuel electrode 15 is electrically connected to the lower connector 13 via the current collecting member 19. In addition, since the stacked body 8 is in a state in which a plurality of fuel cells 1 are stacked and connected in series, the upper end plate 45a is a positive electrode and the lower end plate 45b is a negative electrode. Energy can be taken out via the fastening members 46a to 46d that also function as output terminals.

As described above, the fuel cell 1 repeats a temperature cycle in which the temperature rises during power generation and the temperature decreases when power generation is stopped. Therefore, thermal expansion and contraction are repeated for all the members constituting the fuel chamber 17 and the air chamber 16 and the fastening members 46a to 46f, and accordingly, the intervals between the fuel chamber 17 and the air chamber 16 are repeatedly expanded and contracted.
Further, the fuel pressure and the air pressure may also fluctuate, and the space between the fuel chambers 17 and the air chambers 16 is enlarged or reduced when the cell body 3 is deformed by the fluctuation of the pressure.
In the embodiment, the change in the expansion direction of the fuel chamber 17 and the air chamber 16 is mitigated by deformation in the surface direction of the sheet member 19a and elongation of the connector-side current collector 19b and the electrode-side current collector 19c. On the contrary, in the embodiment, in response to a change in the direction in which the distance between the fuel chamber 17 and the air chamber 16 is reduced, the sheet member 19a is deformed in the surface direction, and the connector-side current collector 19b and the electrode-side current collector 19c. The stress is relieved by shrinkage.

As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to the said embodiment. For example, the sheet member 19a is formed into a plurality of strips as shown in FIG. 13 so as to intersect with the connector-side current collector 19b and the electrode-side current collector 19c, and the entire current collecting member 19 is formed into a lattice shape so as to be air permeable. You may make it raise.
Further, the connector-side current collector 19b and the electrode-side current collector 19c may be formed into a square chip shape as shown in FIG. 14 and bonded to the sheet member 19a.
In the embodiment, the first interposed member 20a is disposed between the cell body 3 and the sheet member 19a and the second interposed member 20b is disposed between the connector 13 and the sheet member 19a. Even when not used, the benefits obtained by implementing the present invention in comparison with the prior art are great.

DESCRIPTION OF SYMBOLS 1 ... Fuel cell 2 ... Electrolyte body 2/1 ... 1st electrolyte body 2/2 ... 2nd electrolyte body 3 ... Cell main body 3/1 ... 1st cell main body 3/2 ... 2nd cell main body 8 ... Fuel cell Stack 12, 13, 12-13 ... connector 14 ... electrode (air electrode)
14/1 ... 1st electrode (air electrode)
14/3 ... 3rd electrode (air electrode)
15 ... Electrode (fuel electrode)
15/2 ... 2nd electrode (fuel electrode)
15/4 ... 4th electrode (fuel electrode)
DESCRIPTION OF SYMBOLS 18 ... Current collecting member 18/2 ... 2nd current collecting member 180 ... Contact part 19 ... Current collecting member 19/1 ... 1st current collecting member 19a ... Sheet member 19b ... Connector side current collector 19c ... Electrode side current collector 20a ... 1st interposed member 20b ... 2nd interposed member L ... Distance H1 ... Thickness of connector side collector H2 ... Thickness of electrode side collector

Claims (10)

A cell body in which electrodes are respectively formed on the front and back surfaces of the plate-like electrolyte body;
A connector having electrical conductivity disposed opposite to the electrode of the cell body;
A fuel cell that is disposed between the electrode and the connector and electrically connects the electrode and the connector;
The current collecting member is
A sheet-like sheet member provided between the connector and the electrode such that one surface faces the connector and the other surface faces the electrode;
A connector-side current collector that is disposed on the one surface of the sheet member and electrically connects the sheet member and the connector;
An electrode-side current collector that is disposed on the other surface of the sheet member and electrically connects the sheet member and the electrode;
The fuel cell, wherein the connector-side current collector and the electrode-side current collector are arranged so as not to overlap when viewed along the thickness direction of the cell body.   2. The fuel cell according to claim 1, wherein the sheet member is made of a member that is more easily deformed than either the connector-side current collector or the electrode-side current collector.   When viewed along the thickness direction of the cell body, the distance (L) between the connector-side current collector and the electrode-side current collector is the thickness of the connector-side current collector in the thickness direction of the cell body ( 3. The fuel cell according to claim 2, wherein the fuel cell is set to be larger than both of H <b> 1) and the thickness (H <b> 2) of the electrode-side current collector in the thickness direction of the cell main body. Between the cell body and the sheet member arranged to face each other,
The first interposition member is disposed at a position overlapping with the connector-side current collector when viewed along the thickness direction of the cell main body. Fuel cell. Between the connector and the sheet member arranged to face each other,
5. The second interposed member is disposed at a position overlapping with the electrode-side current collector when viewed along the thickness direction of the cell main body. 6. Fuel cell.   The fuel cell according to claim 1, wherein the seat member has a structure having a vent hole.   The fuel cell according to claim 6, wherein the sheet member is a mesh.   The fuel cell according to any one of claims 1 to 7, wherein the electrode-side current collector is made of at least one of Ni cermet, felt, or non-woven fabric. The connector has a plate shape forming two main surfaces,
Two adjacent cell bodies are respectively disposed on two main surface sides of the connector,
When one of the two cell bodies is a first cell body and the other is a second cell body,
A first current collecting member that electrically connects the first cell body and the connector is disposed on one main surface of the connector on the first cell body side,
A second current collecting member for electrically connecting the second cell main body and the connector is disposed on the other main surface of the connector on the second cell main body side,
When viewed along the thickness direction of the cell body, the electrode-side current collector of the first current collector and the connector-side current collector of the second current collector are arranged so as not to overlap. The fuel cell according to any one of claims 1 to 8, wherein: A plate-like connector having first and second main surfaces;
A first cell main body provided with first and second electrodes on both sides of the plate-shaped first electrolyte body, the first electrode being disposed toward the first main surface of the connector;
A second cell main body provided with third and fourth electrodes on both sides of the plate-like second electrolyte body, respectively, the fourth electrode being arranged toward the second main surface of the connector;
A contact portion formed on the first main surface of the connector and in contact with the surface of the first electrode of the first cell body;
A current collecting member disposed between the fourth electrode of the second cell main body and the second main surface of the connector, and electrically connecting the fourth electrode and the connector;
A fuel cell comprising:
The current collecting member is
A sheet-like sheet member having electrical conductivity, disposed between the connector and the fourth electrode such that one surface faces the connector and the other surface faces the fourth electrode;
A connector-side current collector that is disposed on the one surface of the sheet member and electrically connects the sheet member and the connector;
An electrode-side current collector disposed on the other surface of the sheet member and electrically connecting the sheet member and the fourth electrode;
When viewed along the thickness direction of the connector,
The fuel cell, wherein the connector-side current collector and the electrode-side current collector, and the connector-side current collector and the contact portion are arranged so as not to overlap each other.

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