JP2011154874A - Cell stack device, fuel cell module, and fuel cell device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cell stack device 1 improved in power generation efficiency. <P>SOLUTION: In the cell stack device 1, a fuel cell 3 is provided with: a conductive support 10 having a first reactant gas passage 9 inside; a laminate having an inner electrode layer 11, a solid electrolyte layer 12, and an outer electrode layer 13 laminated in this order; and an inter-connector 14, wherein the space between the adjoining fuel cells 3 is constituted as a second reactant gas passage 8. The current collector member 4 has a plurality of sets formed continuously with: a pair of current collection pieces 4a, 4b which connect the outer electrode layer 13 of one of adjoining fuel battery cells 3 and the inter-connector 14 of the other adjoining fuel battery cell 3; and a connection part 4c which connects the end parts of the pair of current collection pieces 4a, 4b as one set. A side plate part 4e which extends along the arrangement direction of the fuel battery cell 3 is provided on the fuel battery cell 3 side which is connected to the connection part 4c and is connected to the current collector member 4 at the outer electrode layer 13. Thus, the cell stack device 1 improved in power generation efficiency can be made. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cell stack device in which a plurality of fuel cells are arranged, a fuel cell module, and a fuel cell device.

  In recent years, as next-generation energy, a plurality of fuel cells that generate power at a high temperature of 600 ° C. to 1000 ° C. using a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air, etc.) via a current collecting member A cell stack device in which cell stacks that are electrically connected in series are fixed to a manifold that supplies reaction gas to the fuel cell, a fuel cell module that houses the cell stack device, and a fuel cell module are housed. Various fuel cell devices have been proposed (see, for example, Patent Document 1).

  In such a cell stack device, fuel gas that has not been used for power generation is combusted on the upper end side of the fuel cell, and the temperature of the fuel cell is increased, thereby efficiently generating power in the fuel cell. Can do.

  Further, in the current collecting member that includes the outer electrode layer side current collecting piece and the interconnector side current collecting piece, which are a pair of current collecting pieces, and whose both end portions are connected by the connecting portion, the second reaction gas is the outer electrode. For the purpose of facilitating passage between the layer and the interconnector, a cell stack device in which the connecting portion of the current collecting member is formed outside the outer electrode layer (see, for example, Patent Document 2) has been proposed. ing.

JP 2007-59377 A JP 2008-135195 A

  However, in the above-described current collecting member, the second reaction gas that flows inside the current collecting member flows out of the cell stack, so that a sufficient amount of the second reaction gas may not be supplied to the outer electrode layer. The power generation efficiency of the cell stack device may be reduced.

  Therefore, an object of the present invention is to suppress the flow of the second reactive gas that has flowed inside the current collecting member to the outside of the cell stack, and to supply a sufficient amount of the second reactive gas to the outer electrode layer. Another object of the present invention is to provide a cell stack device, a fuel cell module and a fuel cell device with improved power generation efficiency.

A cell stack device according to the present invention comprises a cell stack comprising a plurality of cell stacks arranged in a standing manner through columnar fuel cells that perform power generation with a first reaction gas and a second reaction gas. An apparatus, wherein the fuel cell is disposed on the conductive support, the conductive support having a first reactive gas flow path for flowing the first reactive gas from the lower end to the upper end, A laminated body in which an inner electrode layer, a solid electrolyte layer, and an outer electrode layer are laminated in this order; and an interconnector disposed on the conductive support so as to face the outer electrode layer. The fuel cell is configured as a second reaction gas flow path for flowing the second reaction gas from below to above, and the current collecting member includes the outer electrode layer of the one adjacent fuel cell and the other Of the fuel cell A pair of plate-like current collecting pieces along the width direction of the fuel cells arranged at a predetermined interval, and the ends of the pair of current collecting pieces are electrically connected to each other. As a set of connecting portions to be connected, a plurality of sets are continuously formed in the longitudinal direction of the fuel cell, and connected to the connecting portion, and the current collecting member and the outer electrode layer A side plate extending along the arrangement direction of the fuel cells is provided on the connected fuel cell side.

  In such a cell stack apparatus, the current collecting member has a predetermined interval for electrically connecting the outer electrode layer of one adjacent fuel cell and the interconnector of the other fuel cell. A pair of plate-like current collecting pieces along the width direction of the arranged fuel cells and a connection portion connecting the ends of the pair of current collecting pieces as a set, continuous in the longitudinal direction of the fuel cells. A plurality of sets are formed and connected to the connection portion, and extend along the arrangement direction of the fuel cells toward the fuel cell connected to the current collecting member and the outer electrode layer. Since the side plate portion is provided, it is possible to suppress the second reaction gas flowing through the second reaction gas channel from flowing out of the cell stack. Thereby, a sufficient amount of the second reactive gas can be supplied to the outer electrode layer, and a cell stack device with improved power generation efficiency can be obtained.

  In the cell stack device of the present invention, it is preferable that the side plate portion extends to the interconnector side of the fuel cell connected to the current collecting member by the outer electrode layer.

  In such a cell stack device, since the side plate portion extends to the interconnector side of the fuel cell connected to the current collecting member and the outer electrode layer, the second reactive gas is further added to the outer electrode layer. Can be supplied.

  Further, in the cell stack device of the present invention, the side plate portion extends along the arrangement direction of the fuel cells to the fuel cell side connected to the current collecting member and the interconnector. It is preferable.

  In such a cell stack device, the side plate portion also extends along the arrangement direction of the fuel cells to the fuel cell connected to the current collector and the interconnector. A second reactive gas can be supplied to the layer.

  In addition, the cell stack device of the present invention has a configuration in which the first reaction gas that is not used for power generation and the second reaction gas that is not used for power generation are combusted on the upper end side of the fuel cell. The upper end of the current collecting member is preferably disposed at a position higher than the upper end of the fuel cell.

  In such a cell stack device, the first reaction gas that is not used for power generation and the second reaction gas that is not used for power generation are burned on the upper end side of the fuel cell, and the upper end of the current collecting member is Since it is arranged at a position higher than the upper end of the fuel cell, the second reaction gas can be efficiently supplied to the upper end side of the fuel cell, and the first reaction gas and the power that were not used for power generation It is possible to efficiently burn the second reaction gas that has not been used for the upper end portion of the fuel cell. Therefore, even when the supply amount of the second reactive gas is small, such as when generating power at a low output, it is possible to suppress the occurrence of misfire.

  In the cell stack device of the present invention, it is preferable that a surface of the side plate portion facing the fuel cell is covered with an insulating layer.

  In such a cell stack device, since the surface of the side plate facing the fuel cell is covered with an insulating layer, even when the side plate is in contact with the fuel cell, it is electrically short-circuited. Can be prevented. Thereby, a cell stack device with improved long-term reliability can be obtained.

  Since the fuel cell module of the present invention is characterized in that the cell stack device is housed in a housing container, the fuel cell module can be improved in power generation efficiency.

  The fuel cell device according to the present invention includes the above fuel module and an auxiliary device for operating the fuel cell module in an outer case, so that the fuel cell device has improved power generation efficiency. it can.

  In the cell stack device of the present invention, the current collecting member has a predetermined interval for electrically connecting the outer electrode layer of one adjacent fuel cell and the interconnector of the other fuel cell. A pair of plate-like current collecting pieces along the width direction of the arranged fuel battery cells and a connection part that connects the ends of the pair of current collecting pieces as one set are continuous in the longitudinal direction of the fuel battery cells. A plurality of sets are formed, and are connected to the connection portion and extend along the arrangement direction of the fuel cells toward the fuel cell connected to the current collecting member and the outer electrode layer. Since the side plate portion is provided, the second reaction gas flowing through the second reaction gas channel can be prevented from flowing out of the cell stack. Thereby, a sufficient amount of the second reactive gas can be supplied to the outer electrode layer, and a cell stack device with improved power generation efficiency can be obtained.

  In addition, by storing the cell stack device in a storage container, a fuel cell module with improved power generation efficiency can be obtained, and further, the fuel cell module and an auxiliary device for operating the fuel cell module are installed on the exterior. By storing in the case, a fuel cell device with improved power generation efficiency can be obtained.

An example of the cell stack apparatus of the present invention is shown, (a) is a side view schematically showing the cell stack apparatus, and (b) is an enlarged part of a portion surrounded by a dotted frame of the cell stack apparatus of (a). It is a top view. It is a perspective view of the current collection member shown in FIG. It is a side view which shows roughly the connection of the fuel cell shown in FIG. 1, and a current collection member. The other example of the cell stack which comprises the cell stack apparatus of this invention is shown, (a) is a top view which shows the connection of a fuel cell and a current collection member roughly, (b) is a fuel cell, It is a side view which shows the connection with a current collection member roughly. It is a perspective view which shows another example of the current collection member which comprises the cell stack apparatus of this invention. 5 shows still another example of the cell stack including the current collecting member shown in FIG. 5, (a) is a plan view schematically showing the connection between the fuel cell and the current collecting member, and (b) is the fuel. It is a side view which shows the connection of a battery cell and a current collection member roughly. It is a perspective view which shows another example of the current collection member which comprises the cell stack apparatus of this invention. It is an external appearance perspective view which shows an example of the fuel cell module of this invention. It is a disassembled perspective view which shows an example of the fuel cell apparatus of this invention.

FIG. 1 shows an example of a cell stack device of the present invention, (a) is a side view schematically showing the cell stack device, (b) is a plan view showing the cell stack device 1 of (a), The part enclosed by the dotted line frame shown in a) is extracted and shown. FIG. 2 is a perspective view of the current collecting member 4 shown in FIG. In the following drawings, the same numbers are assigned to the same members.

  The cell stack device 1 has a plurality of first reaction gas flow paths 9 with a predetermined interval inside, and an electrically conductive support 10 having an elliptic cylinder shape as a whole having a pair of opposed flat surfaces. The inner electrode layer 11, the solid electrolyte layer 12, and the outer electrode layer 13 are laminated in this order on one flat surface, and the outer electrode layer 13 and the solid electrolyte layer 12 are formed on the other flat surface. By disposing the columnar (hollow flat plate-like) fuel cells 3 in which the interconnectors 14 are laminated at the unexposed portions in a state of being erected via the current collecting members 4, the fuel cells 3 are electrically connected to each other. A cell stack 2 connected in series is provided.

  As will be described in detail later, the current collecting member 4 is provided with a plurality of slits in the width direction at a predetermined interval on a single plate member, and portions adjacent in the vertical direction across the slits are current collecting pieces 4a and 4b. . The current collecting pieces 4 a and 4 b formed in the longitudinal direction of the current collecting member 4 are alternately arranged so as to be joined to the adjacent fuel cell 3 on the one side and the adjacent fuel cell 3 on the other side. Has been. And the both ends of a pair of current collection piece 4a, 4b are connected by the connection part 4c, these sets are made into one set, and the multiple sets are formed in the longitudinal direction, and the current collection member 4 is comprised. As a result, the second reaction gas flow path 8 in which the second reaction gas flows between the current collection piece 4a on the side of the adjacent one of the fuel cells 3 and the current collection piece 4b on the side of the other fuel cell 3 that is adjacent. It becomes.

  A P-type semiconductor layer 15 can also be provided on the outer surface of the interconnector 14. By connecting the current collecting member 4 to the interconnector 14 via the P-type semiconductor layer 15, the contact between the two becomes an ohmic contact, thereby reducing the potential drop and effectively suppressing the decrease in the current collecting performance. it can. The P-type semiconductor layer 15 can also be provided on the outer surface of the outer electrode layer 13.

  Then, the lower end portion of each fuel cell 3 constituting the cell stack 2 has a glass sealant (see FIG. 5) on the manifold 7 for supplying the first reaction gas to the fuel cell 3 via the first reaction gas flow path 9. (Not shown) or the like.

  In the cell stack device 1 shown in FIG. 1, as the fuel battery cell 3, the fuel gas (hydrogen-containing gas) flows in the first reaction gas flow path 9, and the fuel electrode layer as the inner electrode layer 11, the outer side 1 shows a solid oxide fuel cell 3 provided with an air electrode layer as an electrode layer 13. Fuel gas is supplied from the manifold 7 as the first reaction gas, and oxygen-containing gas (air or the like) is supplied as the second reaction gas between the adjacent fuel cells 3, thereby generating power in the fuel cells 3. In the following description, a case where a fuel gas is used as the first reaction gas and an oxygen-containing gas is used as the second reaction gas will be described as an example.

  The cell stack device 1 holds the cell stack 2 from both ends in the arrangement direction of the fuel cells 3 (hereinafter sometimes abbreviated as the cell arrangement direction) via end current collecting members (not shown). As described above, an electrically deformable conductive member 5 having a lower end fixed to the manifold 7 is provided. Here, in the conductive member 5 shown in FIG. 1, a current extraction portion 6 for extracting current generated by power generation of the cell stack 2 (fuel cell 3) in a shape extending outward along the cell arrangement direction. Is provided. In addition, as an edge part current collection member, the thing of the structure similar to the current collection member 4 may be used, and the thing of a different structure may be used.

In such a cell stack device 1, the fuel discharged from the first reaction gas flow path (fuel gas flow path) 9 on the upper end side of the fuel battery cell 3 and not used for power generation of the fuel battery cell 3. By combusting the gas and the oxygen-containing gas discharged from the second reaction gas channel 8 (oxygen-containing gas channel) and not used for power generation of the fuel cell 3, the fuel cell 3 The temperature can be raised or maintained at a high temperature, and the power generation of the fuel cell 3 (cell stack device 1) can be performed efficiently.

  Below, each member which comprises the fuel cell 3 shown in FIG. 1 is demonstrated.

As the fuel electrode layer (inner electrode layer) 11, generally known ones can be used, and porous conductive ceramics such as ZrO ₂ (stabilized) in which rare earth elements such as Y and Yb are dissolved. Zirconia) and Ni and / or NiO.

In the fuel electrode layer 11, at least one of Ni and NiO and the content of ZrO ₂ in which the rare earth element is in solid solution are such that the volume ratio after calcination-reduction is ZrO in which NiO: rare earth element is in solid solution. ₂ (for example, NiO: YSZ) is preferably in the range of 35:65 to 65:35. Further, the porosity of the fuel electrode layer 11 is preferably 15% or more, particularly preferably in the range of 20 to 40%, and the thickness thereof is preferably 1 to 30 μm.

The solid electrolyte layer 12 has a function as an electrolyte for bridging electrons between the electrodes, and at the same time, has to have a gas barrier property in order to prevent leakage between the fuel gas and the oxygen-containing gas. , 3 to 15 mol% of rare earth elements are formed from ZrO ₂ as a solid solution. In addition, as long as it has the said characteristic, you may form using another material etc.

  Further, the solid electrolyte layer 12 is desirably a dense material having a relative density (according to Archimedes method) of 93% or more, particularly 95% or more in terms of preventing gas permeation, and a thickness of 5 to 50 μm. Preferably there is.

The air electrode layer (outer electrode layer) 13 can be formed of conductive ceramics (for example, ABO ₃ type perovskite oxide) and needs to have gas permeability. Therefore, the porosity is 20% or more. In particular, it is preferably in the range of 30 to 50%. Furthermore, the thickness of the air electrode layer 13 is preferably 30 to 100 μm from the viewpoint of current collection.

Although the interconnector 14 can be formed from conductive ceramics, it is required to have reduction resistance and oxidation resistance because it is in contact with a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air, etc.). Therefore, a lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) is preferably used. The interconnector 14 leaks fuel gas that flows through a plurality of first reaction gas flow paths (fuel gas flow paths) 9 formed in the conductive support 10 and oxygen-containing gas that flows outside the conductive support 10. In order to prevent this, it must be dense and preferably has a relative density of 93% or more, particularly 95% or more.

  Further, the thickness of the interconnector 14 is preferably 10 to 50 μm for the purpose of preventing gas leakage and suppressing an increase in electrical resistance. If the thickness is smaller than this range, gas leakage is liable to occur. If the thickness is larger than this range, the electric resistance is large, and the current collecting function may be lowered due to a potential drop.

  The conductive support 10 is required to be gas permeable in order to allow the fuel gas to permeate to the fuel electrode layer 11 and further to be conductive in order to collect current via the interconnector 14. . Therefore, as the conductive support 10, it is necessary to adopt a material satisfying such a requirement as a material, and for example, conductive ceramics, cermet, or the like can be used.

In producing the fuel cell 3, in the case of producing the conductive support 10 by simultaneous firing with the fuel electrode layer 11 or the solid electrolyte layer 12, the conductivity is made from the iron group metal component and the specific rare earth oxide. It is preferable to form the support 10. The conductive support 10 preferably has an open porosity of 30% or more, particularly 35 to 50% in order to provide the required gas permeability, and the conductivity is 50 S / cm or more. More preferably, it is 300 S / cm or more, and particularly preferably 440 S / cm or more.

  Further, the length of the flat surface n of the conductive support 10 (height in the width direction of the conductive support 10) is usually 15 to 35 mm, and the length of the arc-shaped surface m (arc length) is 2 The thickness of the conductive support 10 (thickness between the flat surfaces n) is preferably 1.5 to 5 mm.

An example of the P-type semiconductor layer 15 is a layer made of a transition metal perovskite oxide. Specifically, a material having higher electron conductivity than the lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) constituting the interconnector 14, for example, LaMnO in which Mn, Fe, Co, etc. exist at the B site. P-type semiconductor ceramics made of at least one of _three- based oxides, LaFeO ₃ -based oxides, LaCoO ₃ -based oxides and the like can be used. In general, the thickness of the P-type semiconductor layer 15 is preferably in the range of 30 to 100 μm.

  Although not shown, the solid electrolyte layer 12 and the air electrode layer 13 are firmly joined between the solid electrolyte layer 12 and the air electrode layer 13, and the components of the solid electrolyte layer 12 and In a composition containing Ce (cerium) and other rare earth elements (Sm, Gd, etc.) for the purpose of suppressing the formation of a reaction layer having a high electrical resistance by reacting with the components of the air electrode layer 13. An intermediate layer may also be provided.

  Further, although not shown, in order to reduce the difference in thermal expansion coefficient between the interconnector 14 and the conductive support 10 between the interconnector 14 and the conductive support 10, the fuel electrode layer 11 may be provided.

  Here, the current collection member 4 which comprises the cell stack apparatus of this invention is demonstrated.

  FIG. 2 is a perspective view of the current collecting member 4 constituting the cell stack device 1 shown in FIG. 1, and FIG. 3 is a side view schematically showing the connection between the fuel cell 3 and the current collecting member 4. .

  The current collecting member 4 constituting the cell stack device 1 of the present invention is a pair of plate-like current collecting pieces provided along the width direction of the fuel cell 3 (hereinafter sometimes abbreviated as the cell width direction). 4a, 4b and the connection part 4c which connects the both ends of a pair of current collection piece 4a, 4b are made into one set, and the several set is provided continuously in the longitudinal direction of the current collection member 4. FIG. The connecting portion 4c is connected to an extending portion 4d extending from the connecting portion 4c to the outside of the fuel cell 3 along the cell width direction, and further connected to the extending portion 4d and connected to the air electrode layer 13. A side plate 4e extending along the cell arrangement direction is provided on the fuel cell 3 side. In addition, a unit including a plurality of sets each including a pair of plate-like current collecting pieces 4 a and 4 b and a connecting portion 4 c that connects both ends of the pair of current collecting pieces 4 a and 4 b is arranged in the longitudinal direction of the current collecting member 4. A conductive connecting portion 4f for connecting is provided. This unit includes an extending portion 4c and a side plate portion 4e described later.

  The current collecting pieces 4 a and 4 b are connected to the current collecting piece 4 a connected to the air electrode layer 13 of one adjacent fuel cell 3 and the current collecting piece connected to the interconnector 14 of the other adjacent fuel cell 3. 4b, and a plurality of current collecting members 4 are provided along the longitudinal direction. As shown in FIG. 2, both end portions of the current collecting pieces 4a and 4b are bent toward the connecting portion 4c, and a plurality of current collecting pieces 4a and 4b are connected at the connecting portion 4c.

One end of an extending portion 4d extending to the outside of the fuel cell 3 along the cell width direction is connected to the connecting portion 4c. As shown in FIG. 1B, the extending portion 4 d has the other end of the extending portion 4 d disposed outside the fuel cell 3. One end of the side plate portion 4e extending along the cell arrangement direction on the fuel cell 3 side connected to the air electrode layer 13 is connected to the other end of the extending portion 4d. In the cell stack device 1 of the present invention, it is preferable to provide the extending portion 4d so as to protrude about 0.5 to 1 cm from the outside of the fuel cell.

  In addition, although the current collection member 4 shown in FIG. 2 showed the example which each provided the connection part 4c, the extending | stretching part 4d, and the side-plate part 4e, if the side-plate part 4e is connected with the current collection member 4, this shape will be shown. It is not limited to. For example, the connecting portion 4c may be extended in the cell width direction and connected to the side plate portion 4e, and the extending portion 4d may be bent toward the fuel cell 3 connected to the current collecting member 4 and the air electrode layer 13. You may produce the side-plate part 4e.

  Then, as shown in FIG. 2, the current collecting member 4 is configured by setting these as one unit and connecting a plurality of units in the longitudinal direction via the conductive connecting piece 4f. In FIG. 2, the number of units is four, but the present invention is not limited to this. The number of units may be set as appropriate depending on the size (length in the longitudinal direction) of the fuel cell 3, the power generation efficiency, the rigidity of the current collecting member 4, and the like.

  The current collecting member 4 needs to be conductive in order to flow the current generated by the fuel battery cell 3, and the cell stack device 1 operates at a high temperature of 600 to 900 ° C., and therefore needs heat resistance. Therefore, it is preferable to use an alloy containing 10 to 30 parts by mass of Cr with respect to 100 parts by mass of the alloy. For example, an Fe—Cr alloy, a Ni—Cr alloy, or the like can be used.

  Then, a plurality of slits are provided in the central portion of one rectangular plate member (rectangular plate) made of an alloy containing Cr at predetermined intervals in the longitudinal direction of the fuel cell 3, and the plate between the slits The members 4a and 4b are formed by alternately projecting the members so as to be connected to the adjacent fuel cells 3, and processing such as notching is performed on both sides (portions where no slits are formed) of the rectangular plate. By doing so, the current collecting member 4 can be produced by forming the predetermined shape and bending the both sides of the cut-out rectangular plate to form the side plate portion 4e. In this case, the current collecting member 4 can be easily produced because the current collecting member 4 can be produced by punching out a single plate member.

  In addition, although the example produced with one rectangular plate was shown, each member may be produced separately and joined by welding etc., and the current collection member 4 may be produced. For example, a pair of current collecting pieces 4a and 4b and a connecting portion 4c for connecting both ends of the pair of current collecting pieces 4a and 4b as one set, and a plurality of sets are connected by a conductive connecting piece 4f. A current collecting member 4 may be produced by producing a stretched portion 4d and a side plate portion 4e by a plate member produced by bending a bent portion (not shown) and joining the current collecting portion to the current collecting portion by welding. In addition, the slits may be formed by an appropriately known method such as press working.

  Here, when the cell stack device generates electric power for a long period of time, Cr diffuses from the Cr-containing alloy to the air electrode layer 13 of the fuel cell 3 or the interface between the air electrode layer 13 and the solid electrolyte layer 12, and is electrically Resistance may increase and the power generation performance of the fuel cell may be reduced. Therefore, a part of the surface of the current collecting member 4, preferably the whole, is preferably covered with a Cr diffusion suppression layer using a perovskite oxide containing a rare earth element. Thereby, it is possible to suppress the diffusion of Cr from the current collecting member 4 to the air electrode layer 13 of the fuel cell 3 or the interface between the air electrode layer 13 and the solid electrolyte layer 12, and the cell stack device 1 with improved power generation efficiency can do.

The cell stack device 1 according to the present invention allows a fuel gas to flow through a first reaction gas flow path (fuel gas flow path) 9 provided inside the fuel battery cell 3 and a second reaction provided between the fuel battery cells 3. Power generation is performed by flowing an oxygen-containing gas through the gas flow path (oxygen-containing gas flow path) 8.

  In the conventional cell stack apparatus, the oxygen-containing gas flows out of the cell stack 2 from the second reaction gas flow path 8, and the amount of oxygen-containing gas supplied to the air electrode layer 13 is still not sufficient. There was a possibility that the power generation efficiency of the device would be reduced.

  In the current collecting member 4 constituting the cell stack device 1 of the present invention, the side plate portion 4e extends along the cell arrangement direction toward the fuel cell 3 side connected by the current collecting member 4 and the air electrode layer 13. Therefore, the oxygen-containing gas can be prevented from flowing outside the cell stack 2. Thereby, a sufficient amount of oxygen-containing gas can be supplied to the air electrode layer (outer electrode layer) 13, and the power generation efficiency of the fuel cell 3 can be improved. Therefore, the cell stack device 1 with improved power generation efficiency can be obtained.

  As shown in FIG. 3, an interconnector 14 is provided on one side main surface 15a of the fuel cell 3 over the entire area in the longitudinal direction of the fuel cell, and an air electrode layer 13 is provided on the other side main surface 15b. 3 except for the upper end and the lower end. The fuel cell 3 has a power generation portion where the inner electrode layer (fuel electrode layer) (not shown), the solid electrolyte layer, and the outer electrode layer (air electrode layer) 13 of the fuel cell 3 are stacked in this order. Generate electricity. In FIG. 3, the P-type semiconductor layer is not shown. The fuel gas is indicated by a solid line arrow, and the oxygen-containing gas is indicated by a broken line arrow.

  Therefore, the length in the longitudinal direction of the current collecting member 4 is preferably equal to or longer than the length in the longitudinal direction of the air electrode layer, whereby efficient current collection can be achieved.

  The length of the current collecting pieces 4a and 4b along the cell width direction is such that the length of the portion in contact with the air electrode layer 13 or the interconnector 14 is equal to the length of the air electrode layer 13 or the interconnector 14 in the width direction or It is preferable to make it longer than that. Thereby, current can be collected efficiently. If the length in the width direction of the current collecting pieces 4a and 4b is too long, the second reaction gas flow path 8 is too wide in the cell width direction, so that a sufficient amount of oxygen-containing gas cannot be supplied. There is a fear, and it is necessary to set appropriately so that a sufficient amount of oxygen-containing gas can be supplied to the air electrode layer 13.

  By the way, since the fuel cell 3 is a conductor, when the side plate portion 4e of the current collecting member 4 comes into contact with the fuel cell 3, the cell stack device 1 may be electrically short-circuited. Reliability may be reduced.

  Therefore, it is preferable that the surface facing the fuel cell 3 of the side plate portion 4e of the current collecting member 4 is covered with an insulating layer. The insulating layer can be manufactured using a known insulating material such as alumina or zinc oxide. Furthermore, it is more preferable that the entire surface of the side plate portion 4e is covered with an insulating layer. Thereby, the cell stack apparatus 1 can be further prevented from being electrically short-circuited. Further, the side plate portion 4e may be formed of an insulator and connected to the extending portion 4d. The extending portion 4d may be covered with an insulating layer. Thereby, the long-term reliability of the cell stack device 1 can be improved.

  Note that the Cr diffusion suppression coating described above does not have to be provided at the site where the insulating coating is applied when the insulating coating is applied. This is because Cr diffusion can be suppressed even in an insulating coating.

Moreover, since the current collecting member 4 of the present invention is provided with the side plate portion 4e outside the fuel cell 3, it can radiate heat more efficiently than the side plate portion 4e, and the current collecting member 4 becomes high temperature. Can be suppressed. Thereby, it can suppress that the current collection member 4 deteriorates by high temperature.

  4A and 4B show another example of the cell stack device of the present invention. FIG. 4A is a plan view schematically showing connection between the fuel cell 3 and the current collecting member 16, and FIG. 4B is a fuel cell. 3 is a side view schematically showing the connection between the current collector 3 and the current collecting member 16. FIG.

  In the current collecting member 16 shown in FIG. 4, the side plate portion 16e is disposed up to the interconnector 14 of the fuel cell 3 connected to the current collecting member 16 by the outer electrode layer 13, and the connecting portion 16c is a fuel. Unlike the current collecting member 4, the configuration extending to the outside of the battery cell 3 is the same as that of the current collecting member 4.

  As shown in FIG. 4A, since the cell stack 2 is formed by arranging a plurality of fuel cells 3 via the current collecting member 16, the side plate portions 16e are continuous along the cell arrangement direction. Therefore, the oxygen-containing gas can be prevented from flowing out of the cell stack 2, the oxygen-containing gas can be further supplied to the air electrode layer 13, and the power generation efficiency of the cell stack device 1 can be further improved. it can.

  Further, since the oxygen-containing gas can be prevented from flowing out of the cell stack 2, a sufficient amount of oxygen-containing gas that has not been used for power generation is supplied to the upper end side (combustion portion) of the fuel cell 3. can do.

  Further, since the side plate portion 16e is arranged up to the interconnector 14 of the fuel cell 3 connected to the current collecting member 16 by the outer electrode layer 13, the side of the fuel cell 3 or the interconnector 14 side is arranged. The flowing oxygen-containing gas can be prevented from flowing out of the cell stack 2 and can be supplied to the air electrode layer 13 and the combustion section.

  The length of the side plate portion 16 e in the longitudinal direction of the current collecting member 16 is preferably equal to or longer than the length of the unit constituting the current collecting member 16. By setting the length equal to that of the unit, the current collecting member 16 can be easily manufactured. Further, the length of the side plate portion 16 e in the longitudinal direction of the current collecting member 16 may be equal to the length of the current collecting member 16 in the longitudinal direction. Thereby, it is possible to further suppress the oxygen-containing gas from flowing out of the cell stack.

  As shown in FIG. 4A, the length of the side plate portion 16e in the cell longitudinal direction is such that the connection of the other current collecting member 16 adjacent to each other through the fuel cell 3 from the connecting portion 16c of one current collecting member 16 is performed. Since it is preferably provided over the portion 16c, it may be set as appropriate according to the cell stack 2.

  By the way, when the adjacent current collecting members 16 come into contact with each other, an electrical short circuit occurs, and there is a possibility that the current collecting member 16 may be damaged. Can do.

  FIG. 5 is a perspective view of a current collecting member 17 constituting the cell stack device 1, showing still another example of the cell stack device of the present invention. 6 shows the cell stack device 1 including the current collecting member 17 shown in FIG. 5, (a) is a plan view schematically showing the connection between the fuel cell 3 and the current collecting member 17, ) Is a side view schematically showing the connection between the fuel cell 3 and the current collecting member 17.

The current collecting member 17 shown in FIG. 5 is connected to the other end of the extending portion 17d whose one end is connected to the connecting portion 17c, and is disposed on the side of each fuel cell 3 adjacent in the cell arrangement direction. 17e. Further, a connecting portion 17 c, an extending portion 17 d and a side plate portion 17 e located at the highest position of the current collecting member 17 are provided extending in the longitudinal direction of the fuel cell 3. In other respects, the configuration is the same as that of the current collecting member 4.

  Since the current collecting member 17 is provided with the side plate portion 17e outside each adjacent fuel cell 3, the oxygen-containing gas can be prevented from flowing out to the outside of the cell stack. A sufficient amount of oxygen-containing gas can be supplied to the combustion section.

  The length of the side plate portions 17e in the cell arrangement direction is preferably long in terms of suppressing the oxygen-containing gas from flowing out of the cell stack 2, but the side plate portions 17e of the adjacent current collecting members 17 do not overlap each other. By providing in, the cost of the current collection member 17 can be reduced, suppressing that oxygen-containing gas flows outside the cell stack 2. FIG.

  In the current collecting member 17 shown in FIG. 6, an example in which the side plate portion 17 e is provided on the outer side of each of the fuel cells 3 joined to the current collecting member 17 in the extending portion 17 d is shown. The current collecting member 17 may be manufactured by providing a single plate member and joining the central portion of the side plate portion 17e and the extending portion 17d.

  Since the current collecting member 17 has the side plate portions 17e connected to the extending portions 17d arranged in the cell arrangement direction, the length of the side plate portions in the cell arrangement direction (in FIG. 5, each side plate portion Even when the sum of the lengths of 17e becomes longer, it is possible to prevent the handling property of the current collecting member 4 from being lowered. In other words, since the side plate portion 17e is connected to the extending portion 17d at the center portion in the cell arrangement direction, even when the side plate portion 17e has a longer length in the cell arrangement direction, Can be shortened. Thereby, the handleability of the current collecting member 17 can be improved.

  Further, even when the side plate portion 17e is formed from a single plate member, since the central portion of the side plate portion 17e and the extending portion 17d are connected, the handling property of the current collecting member 17 can be improved. .

  Here, the cell stack apparatus 1 of the present invention is configured to burn a fuel gas and an oxygen-containing gas that have not been used for power generation. At night and the like when the amount of electricity used is small, the fuel gas and oxygen-containing gas supplied to the cell stack 2 are reduced, and the cell stack 2 is also at a low temperature, so misfire is likely to occur.

  In the current collecting member 17 constituting the cell stack device 1 of the present invention, the connecting portion 17c, the extending portion 17d, and the side plate portion 17e positioned at the highest position are provided extending in the longitudinal direction of the fuel cell 3. The second reaction gas channel 8 can be formed up to the vicinity of the upper end of the fuel cell 3. Thereby, the oxygen-containing gas that has not been used for power generation flowing through the second reaction gas flow path can be efficiently supplied to the upper end side of the fuel cell 3, and the amount of oxygen-containing gas supplied to the cell stack 2. Even when there is little, it can suppress that misfire occurs.

  FIG. 7 shows still another example of the cell stack device of the present invention, and is a perspective view of a current collecting member 18 constituting the cell stack device 1. The current collecting member 18 has a configuration different from that of the current collecting member 4 described above.

The current collecting member 18 includes a plurality of current collecting pieces 18a connected to one of the adjacent fuel cells 3;
A plurality of current collecting pieces 18b connected to the other adjacent fuel cell 3; a conductive connecting piece 18g for connecting one end of the current collecting piece 18a and the other end of the current collecting piece 18b; A conductive connecting piece 18 h for connecting the other end of the electric piece 18 a and one end of the current collecting piece 18 b is formed as a unit and is continuously formed in the longitudinal direction of the fuel cell 3. The current collecting member 18 is provided with an extending portion 18d extending from the connecting portion 18c to the current collecting pieces 18a and 18b and the conductive connecting pieces 18g and 18h to the outside of the fuel cell 3 along the cell width direction. A side plate portion 18e is provided which is connected to the extending portion 18d and arranged outside the fuel cell 3 connected to the current collecting member 18 and the air electrode layer 13.

  Also in such a current collecting member 18, a sufficient amount of oxygen-containing gas can be supplied to the air electrode layer 13, and a cell stack device with improved power generation efficiency can be obtained.

  Further, since one plate member is provided as the side plate portion 18e, and the side plate portion 18e and the connection portion 18c are connected by the extending portion 18d, the current collecting member 18 can be easily manufactured. Thereby, the manufacturing cost of the current collection member 18 can be reduced.

  In the current collecting member 18 shown in FIG. 7, the side plate portion 18e is composed of a single plate member and a plurality of extending portions 18d are provided. However, the side plate portion 18e is formed by a plurality of plate members. Also good. Moreover, you may form the current collection member 18 from only one, without providing the extending | stretching part 18d in multiple numbers.

  The current collecting member 18 can be manufactured by the same method as the other current collecting members described above. For example, it can be produced by pressing a single plate member (rectangular plate) so as to obtain a predetermined cutout, and appropriately bending the cutout rectangular plate.

  FIG. 8 is an external perspective view showing an example of a fuel cell module 25 in which the cell stack device 1 of the present invention is accommodated in a storage container. The cell shown in FIG. The stack apparatus 1 is accommodated.

  A reformer 27 for reforming raw fuel such as natural gas or kerosene to generate fuel gas is disposed above the cell stack 2 in order to obtain fuel gas used in the fuel cell 3. ing. The fuel gas generated by the reformer 27 is supplied to the manifold 7 via the gas flow pipe 28, and enters the first reaction gas channel 9 provided inside the fuel battery cell 3 via the manifold 7. Supplied.

  FIG. 8 shows a state in which a part (front and rear surfaces) of the storage container 26 is removed, and the cell stack device 1 and the reformer 27 housed inside are taken out rearward. Here, in the fuel cell module 25 shown in FIG. 1, the cell stack device 1 can be slid and stored in the storage container 26. The cell stack device 1 may include the reformer 27.

  In addition, the second reaction gas introduction member 29 provided inside the storage container 26 is disposed between the cell stacks 2 juxtaposed to the manifold 7 in FIG. 8, and the second reaction gas (oxygen-containing gas) is provided. The oxygen-containing gas is supplied to the lower end of the fuel cell 3 so that the side of the fuel cell 3 flows from the lower end toward the upper end in accordance with the flow of the fuel gas. Then, the temperature of the fuel cell 3 is increased by burning the fuel gas and the oxygen-containing gas discharged from the first reaction gas flow path 9 of the fuel cell 3 on the upper end side of the fuel cell 3 or High temperature can be maintained. Further, the fuel gas discharged from the fuel gas flow path of the fuel battery cell 3 and the oxygen-containing gas are combusted on the upper end portion side of the fuel battery cell 3 so that the upper side of the fuel battery cell 3 (cell stack 2). It is possible to efficiently warm the reformer 27 disposed in the. Thereby, the reforming reaction can be efficiently performed in the reformer 27.

  Furthermore, in the fuel cell module 25 of the present invention, since the cell stack device 1 configured using the fuel cell 3 with improved long-term reliability is stored in the storage container 26, the long-term reliability is improved. The fuel cell module 25 can be obtained.

  Here, if a misfire occurs in the cell stack device 1, the temperature of the fuel cell module 25 decreases, and the reformer 27 cannot be sufficiently warmed, and low-productivity fuel gas is supplied to the fuel cell 3. As a result, the fuel cell 3 is deteriorated, and the long-term reliability of the fuel cell module 25 may be reduced.

  In the fuel cell module 25 of the present invention, since the cell stack device 1 capable of suppressing misfire is housed in the housing container 26, the fuel cell module 25 with improved long-term reliability can be obtained.

  FIG. 9 is an exploded perspective view showing an example of the fuel cell device 30 according to the present invention in which the fuel cell module 25 shown in FIG. 8 and an auxiliary machine for operating the cell stack device 1 are housed in an outer case. It is. In FIG. 9, a part of the configuration is omitted.

  The fuel cell apparatus 30 shown in FIG. 9 has a module housing chamber 34 in which the inside of an exterior case composed of a column 31 and an exterior plate 32 is partitioned vertically by a partition plate 33 and the upper side thereof accommodates the fuel cell module 25 described above. The lower side is configured as an auxiliary equipment storage chamber 35 for storing auxiliary equipment for operating the fuel cell module 25. It should be noted that auxiliary equipment stored in the auxiliary equipment storage chamber 35 is omitted.

  Further, the partition plate 33 is provided with an air circulation port 36 for flowing the air in the auxiliary machine storage chamber 35 to the module storage chamber 34 side, and a part of the exterior plate 32 constituting the module storage chamber 34 An exhaust port 37 for exhausting the air in the module storage chamber 34 is provided.

  In such a fuel cell device 30, as described above, the fuel cell module 25 with improved long-term reliability is housed in the module storage chamber 34, so that the fuel cell device 30 with improved long-term reliability is provided. can do.

  Although the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and improvements can be made without departing from the scope of the present invention.

  For example, in the cell stack apparatus 1 described above, the case where the fuel gas is used as the first reaction gas and the oxygen-containing gas is used as the second reaction gas is exemplified. However, the oxygen-containing gas is used as the first reaction gas, and the second reaction gas is used. It can also be set as the structure which uses fuel gas as. In this case, the fuel cell 3 is configured such that the inner electrode layer is the air electrode layer 13 and the outer electrode layer is the fuel electrode layer 11, an oxygen-containing gas is supplied to the first reaction gas flow path 9, and the second The fuel gas may be supplied to the reaction gas channel 19. In this case, the configuration of the storage container 21 constituting the module 20 may be changed as appropriate.

1: Cell stack device 2: Cell stack 3: Fuel cell 4, 16, 17, 18: Current collecting members 4a, 4b, 16a, 16b, 17a, 17b, 18a, 18b: Current collecting pieces 4c, 16c, 17c, 18c: connecting portions 4d, 17d, 18d: extending portions 4e, 16e, 17e, 18e: side plate portions 4f, 16f, 17f: conductive connecting portion 8: second reactive gas flow channel 9: first reactive gas flow channel 18g, 18h: Conductive connection piece 25: Fuel cell module 30: Fuel cell device

Claims (7)

A cell stack device comprising a cell stack in which a plurality of columnar fuel cells that generate power with a first reaction gas and a second reaction gas are erected and arranged via a current collecting member,
The fuel battery cell includes a conductive support having a first reactive gas channel for flowing the first reactive gas from the lower end to the upper end, and an inner electrode layer, a solid disposed on the conductive support. A laminate formed by laminating an electrolyte layer and an outer electrode layer in this order; and an interconnector disposed on the conductive support so as to face the outer electrode layer, and between adjacent fuel cells. It is configured as a second reaction gas channel for flowing the second reaction gas from below to above,
The current collecting member is disposed at a predetermined interval to electrically connect an outer electrode layer of one of the adjacent fuel cells and an interconnector of the other adjacent fuel cell. A set of a pair of plate-like current collecting pieces along the width direction of the battery cell and a connecting portion for connecting the ends of the pair of current collecting pieces as a set, a plurality of continuously A pair is formed,
A side plate portion that is connected to the connecting portion and that extends along the arrangement direction of the fuel cells on the fuel cell side connected to the current collecting member and the outer electrode layer. A cell stack device.   2. The cell stack device according to claim 1, wherein the side plate portion extends to the interconnector side of the fuel cell connected to the current collector and the outer electrode layer.   The said side plate part is extended along the arrangement direction of the said fuel cell also to the said fuel cell side connected with the said current collection member and the said interconnector. Cell stack equipment.   The first reaction gas not used for power generation and the second reaction gas not used for power generation are combusted on the upper end side of the fuel cell, and the upper end of the current collecting member is the fuel. The cell stack device according to any one of claims 1 to 3, wherein the cell stack device is disposed at a position higher than an upper end of the battery cell.   The cell stack device according to any one of claims 1 to 4, wherein a surface of the side plate portion facing the fuel battery cell is covered with an insulating layer.   6. A fuel cell module comprising the cell stack device according to claim 1 stored in a storage container.   7. A fuel cell device comprising: the fuel cell module according to claim 6; and an auxiliary machine for operating the fuel cell module, housed in an outer case.

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