JP2011049021A - Cell stack device, fuel battery module, and fuel battery device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cell stack device with degradation or damage of fuel battery cells restrained, a fuel battery module, and a fuel battery device. <P>SOLUTION: The cell stack device 1 has, at a top end part of a fuel battery cell 3 constituting the cell stack device 1, a lid member 8 formed of a ceramic material which has a space formed against each of both main faces of the fuel battery cell 3, making each space as a second reaction gas flow channel for second reaction gas supplied outside the fuel battery cell 3 to flow through, and is provided with a mixture flow channel for mixing the second reaction gas flowing through the second gas flow channel and first reaction gas exhausted from a first reaction gas flow channel 9, and an exhaust port for exhausting a mixture gas mixed by flowing through the mixture flow channel at a top face. Thereby, degradation or damage of the fuel battery cells 3 can be restrained. <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 including the cell stack device, 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).

  FIG. 6 is an external perspective view showing a conventional fuel cell module 40. Such a fuel cell module 40 is configured by storing a cell stack device 47 in a storage container 41. Here, as the cell stack device 47, a plurality of flat fuel cells 42 are arranged in a state of being erected with a current collecting member interposed therebetween to constitute a cell stack 43, and the cell stack 43 is Each fuel battery cell 42 to be configured is fixed to a manifold 44 for supplying fuel gas to a gas flow path (not shown) provided inside the fuel battery cell 42 by an adhesive material such as glass. A stack device 47 is configured. In FIG. 6, a reformer 45 for generating fuel gas to be supplied to the manifold 44 is disposed above the cell stack device 47 (cell stack 43). Are connected by a fuel gas supply pipe 46.

  In such a cell stack device, fuel gas that has not been used in the power generation of the fuel cell is burned on the upper end side of the fuel cell, and the temperature of the fuel cell is increased, thereby increasing the temperature of the fuel cell. Power generation can be performed efficiently.

  In addition, a cell stack device having a structure in which an annular member is mounted on the upper end portion side of the fuel battery cell in order to suppress the upper end portion side of the fuel battery cell from being oxidized by the oxygen-containing gas supplied to the fuel battery cell ( For example, refer to Patent Document 2.), or a configuration in which a lid-like member is provided on the upper end side of the fuel cell for the purpose of uniformly supplying the reaction gas to a plurality of gas flow paths provided inside the fuel cell. A cell stack apparatus (see, for example, Patent Document 3) has been proposed.

JP 2007-59377 A JP-A-2005-346988 JP 2004-207006 A

  However, in the cell stack device configured to burn the fuel gas that has not been used for power generation of the fuel battery cell on the upper end side of the fuel battery cell, the fuel battery cell generates power on the upper end side of the fuel battery cell. By burning the unused fuel gas, the temperature on the upper end side of the fuel cell rises, and there is a possibility that a part of the fuel cell is deteriorated or damaged.

  Further, when an annular member or a lid-like member is provided on the upper end side of the fuel cell so as to cover the upper end side of the fuel cell, the fuel gas and oxygen-containing gas that are not used for power generation of the fuel cell The fuel gas that has not been used for power generation of the fuel battery cell may be difficult to burn efficiently.

  Therefore, the present invention can sufficiently mix the fuel gas not used for power generation of the fuel cell and the oxygen-containing gas, and efficiently burns the fuel gas not used for power generation of the fuel cell. An object of the present invention is to provide a cell stack device capable of suppressing deterioration and breakage of a fuel cell, a fuel cell module including the cell stack device, and a fuel cell device.

  The cell stack device of the present invention has an inner electrode layer, a solid electrolyte layer, a main surface on one side of a flat conductive support having a first reaction gas channel for flowing a first reaction gas therein, An outer electrode layer is provided in this order, and a plurality of fuel cells each having an interconnector provided on the other main surface are arranged in a state where a plurality of fuel cells are erected with a current collecting member interposed therebetween. A cell stack configured to generate power in the fuel cell by using the second reaction gas and the first reaction gas supplied between the matching fuel cells, and fixing the lower end of the fuel cell, A manifold for supplying a first reaction gas to the fuel cell, and the first reaction gas not used for power generation of the fuel cell above the upper end of the fuel cell and the Burn the second reactive gas In the cell stack device configured as described above, a lid-like member is disposed at an upper end portion of the fuel cell, and the lid-like member is formed on the one-side main surface and the other-side main surface of the fuel cell. A space is formed with each of the second reaction gas flow paths, and a second reaction gas flow path for flowing a second reaction gas supplied between the fuel cells adjacent to each other is formed. A mixing channel that mixes the flow of the second reaction gas and the first reaction gas discharged from the first reaction gas channel is provided, and the upper surface is mixed by flowing through the mixing channel. An exhaust port for discharging the mixed gas is provided, and the exhaust port is formed of a ceramic material.

  In such a cell stack device, the lid-like member forms a space with each of the one main surface and the other main surface of the fuel cell, and the second reaction supplied between the fuel cells. The second reaction gas flow path for the gas flow, the second reaction gas flowing through the second reaction gas flow path, and the first reaction gas discharged from the first reaction gas flow path Since the mixing flow path for mixing is provided, the first reaction gas and the second reaction gas that have not been used for the power generation of the fuel battery cell can be efficiently mixed.

  Then, the mixed gas flowing through the mixing channel is exhausted from the exhaust port provided on the upper surface of the lid member provided at the upper end of the fuel cell, and the mixed gas is combusted mainly above the exhaust port. Is done. Therefore, since the mixed gas in which the first reaction gas and the second reaction gas are efficiently mixed is burned, the first reaction gas and the second reaction that are not used for power generation of the fuel cell. Gas will burn efficiently.

  Moreover, by forming the lid-like member with a ceramic material, it is possible to suppress the breakage of the lid-like member, and to suppress the transfer of combustion heat generated by the combustion of the mixed gas to the upper end portion of the fuel cell, It can suppress that the temperature of the upper end part of a fuel cell rises too much. Thereby, deterioration and breakage of the fuel battery cell can be suppressed.

  In the cell stack device of the present invention, it is preferable that the mixing channel has a tapered shape toward the exhaust port.

  In such a cell stack device, the mixing flow path provided in the lid-like member is tapered toward the exhaust port, so that it is used for power generation of the fuel cell in the mixing flow path. Since it is possible to suppress the combustion of the first reaction gas and the second reaction gas that have not been performed, the temperature of the upper end of the fuel cell can be prevented from rising excessively, and one of the fuel cells. Deterioration and breakage of the part can be suppressed.

  The cell stack device of the present invention includes a plurality of lid-like members corresponding to the respective fuel cells constituting the cell stack, and each of the lid-like members constitutes the cell stack. Each of the fuel cells is arranged in a non-bonded state at the upper end of each of the fuel cells, and each lid member is sandwiched from both ends of the cell stack in the arrangement direction of the fuel cells. It is preferable to provide a fixing member for fixing the lid-like member.

  In such a cell stack device, the lid-like member is disposed in a non-bonded state at the upper end of the fuel cell constituting the cell stack, that is, by covering the lid-like member from above the fuel cell. Since it can arrange | position, the process for joining a fuel cell and a lid-like member becomes unnecessary, and it can reduce manufacturing cost.

  Here, since each cover member is provided with a fixing member for fixing each cover member by sandwiching the cover member from both ends of the cell stack in the arrangement direction of the fuel cells, the cover member is effectively Can be fixed.

  Since the fuel cell module of the present invention is characterized in that the cell stack device is housed in a housing container, deterioration and breakage of the fuel cell can be suppressed, and long-term reliability is improved. It can be a fuel cell module.

  The fuel cell device of the present invention is a fuel cell device with improved long-term reliability because the fuel module and the auxiliary machine for operating the fuel cell module are housed in an outer case. Can do.

  In the cell stack device of the present invention, a space is formed in each of the one main surface and the other main surface of the fuel cell at the upper end of the fuel cell, and the space is supplied between the fuel cells. The second reaction gas flow path for the reaction gas to flow, and the second reaction gas flowing through the second reaction gas flow path and the first reaction discharged from the first reaction gas flow path A mixing channel for mixing gas is provided, and an upper surface is provided with an exhaust port for discharging the mixed gas flowing through the mixing channel and a lid-like member formed of a ceramic material is provided. Therefore, it is possible to efficiently mix the first reaction gas and the second reaction gas that have not been used for power generation of the fuel battery cell, and the mixed gas is disposed above the exhaust port of the lid-like member. Can be burned efficiently. Further, by forming the lid-like member from a ceramic material, it is possible to suppress the heat of combustion generated by the fuel of the mixed gas from being transferred to the upper end portion of the fuel cell, so that the temperature of the upper end portion of the fuel cell is reduced. An excessive increase can be suppressed, and deterioration or breakage of the fuel cell can be suppressed. In addition, by storing this cell stack device in a storage container, it is possible to obtain a fuel cell module with improved long-term reliability. Further, the fuel cell module and an auxiliary device for operating the fuel cell module are provided. By storing in the outer case, a fuel cell device with improved long-term reliability can be obtained.

An example of the cell stack apparatus of this invention is shown, (a) is a side view which shows a cell stack apparatus schematically, (b) is a plane which extracts and shows a part of (a) in the state which removed the lid-shaped member. FIG. FIG. 3 is a perspective view schematically showing an extracted fuel cell and a lid-like member in an example of the cell stack device of the present invention. (A) is sectional drawing which extracts and shows the fuel cell in an example of the cell stack apparatus of this invention, and a cover-like member, (b) is the fuel cell in the other example of the cell stack apparatus of this invention, and It is sectional drawing which extracts and shows a lid-shaped member. It is a side 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. It is an external appearance perspective view which shows an example of the conventional fuel cell module.

  FIG. 1 shows an example of a cell stack device according to the present invention. FIG. 1 (a) is a side view schematically showing the cell stack device, and FIG. 1 (b) shows a part of the cell stack device 1 of FIG. It is a top view enlarged and shown in the state where it removed, and has shown and extracted the part enclosed with the dotted line frame shown in (a). In the following drawings, the same numbers are assigned to the same members.

  Here, the cell stack device 1 has a first reaction gas channel 9 inside, and an inner electrode layer on one flat surface of a flat conductive support 10 having a pair of opposed flat surfaces. 11, a solid electrolyte layer 12, and an outer electrode layer 13 are stacked in this order, and a columnar shape in which an interconnector 14 is stacked on a portion of the other flat surface where the outer electrode layer 13 is not formed ( A cell stack 2 in which the fuel cells 3 are electrically connected in series by arranging the fuel cells 3 in the form of a hollow plate) with the current collectors 4 interposed therebetween. I have.

  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 is provided with a glass sealing material on the manifold 7 for supplying the first reaction gas to the fuel cell 3 via the first reaction gas channel 9. It is fixed by a bonding material such as (not shown).

  In the cell stack device 1 shown in FIG. 1, as the fuel cell 3, a fuel gas (hydrogen-containing gas) is allowed to flow in the first reaction gas flow path 9, and the fuel electrode layer is formed as the inner electrode layer 11. A solid oxide fuel cell 3 provided with an air electrode layer as an electrode layer 13 is shown. A fuel gas is supplied as a first reaction gas from a manifold 7, and a second gas is supplied between adjacent fuel cells 3. By supplying an oxygen-containing gas (air or the like) as the reaction gas, power generation of the fuel cell 3 is performed. 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.

  In addition, the cell stack device 1 includes an elastically deformable conductive member 5 having a lower end fixed to the manifold 7 so as to sandwich the cell stack 2 from both ends in the arrangement direction of the fuel cells 3 via the current collecting members 4. It has. Here, the conductive member 5 shown in FIG. 1 has a shape that extends outward along the arrangement direction of the fuel cells 3 and draws out current generated by the power generation of the cell stack 2 (fuel cells 3). A current drawing portion 6 is provided.

  In such a cell stack device, on the upper end side of the fuel cell 3, the fuel gas discharged from the first reaction gas flow path 9 and not used in power generation of the fuel cell 3 is burned. By doing so, the temperature of the fuel cell 3 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.

  Here, in the cell stack apparatus 1 shown in FIG. 1, a lid-like member 8 is arranged at the upper end of each fuel cell 3, and each of these lid-like members 8 is arranged so as to sandwich the cell stack 2. It is sandwiched between the conductive members 5. The lid-like member 8 will be described later.

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

As the fuel electrode layer 11, generally known materials can be used, and porous conductive ceramics such as ZrO ₂ (referred to as stabilized zirconia) in which a rare earth element is dissolved and Ni and / or NiO are used. And can be formed from

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.

The air electrode layer 13 is not particularly limited as long as it is generally used. For example, the air electrode layer 13 can be formed of a conductive ceramic made of a so-called ABO ₃ type perovskite oxide. The air electrode layer 13 is required to have gas permeability, and the open porosity is preferably 20% or more, particularly preferably in the range of 30 to 50%.

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 is for preventing leakage of fuel gas flowing through the plurality of first reaction gas flow paths 9 formed in the conductive support 10 and oxygen-containing gas flowing outside the conductive support 10. It must be dense and preferably has a relative density of 93% or more, particularly 95% or more.

  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 preparing the fuel cell 3, in the case where the conductive support 10 is manufactured by co-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. Further, 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 300 S / cm or more. In particular, it is preferably 440 S / cm or more.

Furthermore, as the P-type semiconductor layer 15, a layer made of a transition metal perovskite oxide can be exemplified. 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 the air electrode are It is formed with 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 layer 13. An intermediate layer can also be provided.

  Further, although not shown, the fuel electrode is provided between the interconnector 14 and the conductive support 10 to reduce a difference in coefficient of thermal expansion between the interconnector 14 and the conductive support 10. An adhesion layer having a composition similar to that of the layer 11 may be provided.

  By the way, in the above-described cell stack device 1, when the fuel gas discharged from the first reaction gas flow path 9 and not used in the power generation of the fuel battery cell 3 is combusted on the upper end side of the fuel battery cell 3. Further, the temperature on the upper end side of the fuel cell 3 rises excessively, and a part of the fuel cell 3 (particularly the upper end side) may be deteriorated or damaged.

  Further, the fuel gas that has not been used for power generation of the fuel cell 3 discharged from the first reaction gas flow path 9 provided inside the conductive support 10 flows between the adjacent fuel cells 3, Since the oxygen-containing gas that was not used for power generation of the fuel cell 3 is mixed and burned by diffusion of these gases, the fuel gas that was not used for power generation of the fuel cell 3 is efficiently burned. There was a risk that it would be difficult.

  Therefore, in the cell stack device 1 of the present invention, the lid-like member 8 is disposed at the upper end portion of the fuel cell 3.

  FIG. 2 is a perspective view schematically showing the fuel cell 3 and the lid-like member 8 that constitute the cell stack device 1, and FIG. 3 (a) is a diagram showing the fuel cell 3 and the lid shown in FIG. FIG. 5B is a cross-sectional view of the fuel cell 3 and the lid-like member 8 in another example of the cell stack device 1.

  The lid-shaped member 8 has a shape in which a convex shape is cut out from a quadrangular shape in the cross-sectional view. When such a lid-like member 8 is arranged at the upper end portion of the fuel cell 3, the inside of the lid-like member 8 and each of the one side main surface and the other side main surface (flat surface) of the fuel cell 3 Between the adjacent fuel cells 3 (outside the fuel cells 3), and a space (second reaction gas) through which oxygen-containing gas (second reaction gas) that is not used for power generation of the fuel cells 3 flows. Two reaction gas channels 16) are formed.

  Further, on the inner side of the lid-like member 8, a flow path is formed above the fuel battery cell 3 for the flow of fuel gas that has not been used for power generation of the fuel battery cell 3. Here, since this flow path is connected to the second reaction gas flow path, the oxygen-containing gas that has not been used for power generation of the fuel cell 3 that flows through the second reaction gas flow path, and the fuel cell The mixed flow path 17 is mixed with fuel gas that has not been used for power generation in the cell 3. Therefore, the fuel gas that has not been used for power generation of the fuel battery cell 3 and the oxygen-containing gas can be mixed efficiently.

  The mixed gas flowing through the mixing channel 17 is exhausted from the exhaust port 18 provided on the upper surface of the lid-like member 8 and burned. Therefore, in the cell stack device 1 configured to burn the fuel gas that is not used in the power generation of the fuel cell 3, the fuel gas that is not used in the power generation of the fuel cell 3 is used in the power generation of the fuel cell 3. After being efficiently mixed with the oxygen-containing gas that has not been produced, it is burned mainly above the exhaust port 18. Therefore, by burning the mixed gas in which the fuel gas that has not been used for the power generation of the fuel cell 3 and the oxygen-containing gas is efficiently mixed, the gas is efficiently burned and the temperature of the fuel cell 3 is efficiently increased. Or can be maintained at high temperatures.

  Further, the fuel gas that has not been used in the power generation of the fuel battery cell 3 is efficiently mixed with the oxygen-containing gas that has not been used in the power generation of the fuel battery cell 3 and then burned mainly above the exhaust port 18. Therefore, the mixed gas is burned at a distance from the upper end of the fuel cell 3. As a result, it is possible to suppress that the heat of combustion caused by the combustion of the fuel gas not used in the power generation of the fuel cell 3 is directly transferred to the upper end of the fuel cell 3. It can suppress that the upper end part of the cell 3 becomes high temperature too much, and can suppress deterioration and breakage of the fuel cell 3.

  Further, since the lid-like member 8 is formed of a ceramic material having low thermal conductivity and heat resistance, the fuel gas that has not been used in the power generation of the fuel cell 3 above the exhaust port 18 is formed. It can further suppress that the combustion heat which arises with combustion transfers to the upper end part of the fuel cell 3. Therefore, it can suppress that the upper end part of the fuel cell 3 becomes too high temperature, and can suppress deterioration and breakage of the fuel cell 3.

  As the ceramic material for forming the lid-like member 8, it is preferable to use a ceramic material having low thermal conductivity and heat resistance, and examples thereof include ceramic materials such as silica, alumina, magnesia, zirconia and the like. it can. Note that these ceramic materials may be partially stabilized ceramic materials or stabilized ceramic materials in which rare earth elements are dissolved.

  Here, when the size (cross-sectional area) of the inlet of the mixing channel 17 is smaller than the size of the exhaust port 18, combustion of the mixed gas may occur in the mixing channel 17. In this case, there is a possibility that deterioration and breakage of the fuel battery cell 3 cannot be effectively suppressed.

  Therefore, in the lid-shaped member 8 shown in FIG. 3B, the mixing channel 19 is tapered toward the exhaust port 18. Thereby, it can suppress that combustion of mixed gas arises in a mixing flow path, and can suppress deterioration and breakage of the fuel cell 3 more.

  Moreover, the above-mentioned lid-shaped member 8 should just be arrange | positioned at the upper end part of the fuel cell 3 which comprises the cell stack 2. FIG. Therefore, in FIG. 1, a plurality of lid-like members 8 corresponding to the fuel cells 3 constituting the cell stack 2 are provided, and each lid-like member 8 is connected to the upper end portion of each fuel cell 3. Although an example of the cell stack device 1 arranged in the above is shown, each of these lid-like members 8 can be formed in an integral shape. In this case, the manufacturing process of the cell stack device 1 can be simplified.

  By the way, with the operation of the cell stack device 1, the fuel cell 3 may be deformed such as warpage. Here, if the lid-like member 8 is joined to the upper end portion of the fuel cell 3, stress may be generated at the upper end portion of the fuel cell 3, and the fuel cell 3 may be damaged.

  Further, in the cell stack device 1 configured to include a plurality of lid-like members 8 corresponding to each fuel battery cell 3 and to arrange each lid-like member 8 at the upper end of each fuel battery cell 3, each lid-like member In the case where 8 is configured to be joined to the upper end portion of each fuel cell 3, the manufacturing process may be complicated.

  Therefore, it is preferable that the cell stack device 1 of the present invention is configured so that the lid-like member 8 is disposed in an unjoined state at the upper end portion of each fuel cell 3. Specifically, as shown in FIG. 2, a part of the inner wall of the lid-like member 8 is formed on both end sides of the fuel cell 3 (reactive gas flow disposed at the end of the conductive support 10. It is preferable to arrange so as to be in contact with a portion located outside the path 9. Thereby, the stress which arises in the upper end part of fuel cell 3 can be relieved, and it can control that damage to fuel cell 3 arises.

  Here, in particular, in the cell stack device 1 having a plurality of lid-like members 8 corresponding to the respective fuel cells 3, each lid-like member 8 is not joined to the upper end portion of each fuel cell 3. Since the lid-shaped member 8 can be easily moved, the stability of the lid-shaped member 8 may be deteriorated. Therefore, it is preferable to provide the cell stack device 1 with a fixing member for sandwiching each lid-like member 8 from both ends of the cell stack 2 along the arrangement direction of the fuel cells 3. Thereby, each lid-like member 8 can be stably disposed on the upper end portion of each fuel cell 3. In addition, in the cell stack apparatus 1 shown in FIG. 1, although the example in which the electrically-conductive member 5 has played the role of the fixing member is shown, it is also possible to provide a fixing member separately.

  In this case, the fixing member (conductive member 5) is preferably configured as a member that can be elastically deformed. Thereby, even when deformation such as warpage occurs in the fuel cell 3, the fixing member (conductive member 5) can be elastically deformed to relieve stress generated at the upper end of the fuel cell 3, Each lid-like member 8 can be stably disposed at the upper end of each fuel cell 3.

  FIG. 4 is a cross-sectional view of a fuel cell module 20 (hereinafter sometimes abbreviated as a module) in which the cell stack device 1 of the present invention is housed in a housing container. The module 20 has the same appearance as the fuel cell module 40 shown in FIG. 6, and the lid-like member 8 is arranged on each fuel cell 42 constituting the cell stack device 47 shown in FIG. It becomes composition.

  The storage container 21 constituting the module 20 has a double structure having an inner wall 22 and an outer wall 23, and an outer frame of the storage container 21 is formed by the outer wall 23, and the cell stack 2 (cell stack device 1) is formed by the inner wall 22. Is formed. The power generation chamber 24 is provided with a reformer 29 including a vaporization unit for generating fuel gas to be supplied to the fuel cell 3 via the manifold 7 and a reforming unit containing a reforming catalyst. Has been. The shape of the reformer 29 is the same as that of the reformer 45 shown in FIG.

  Further, in the module 20 (storage container 21), a gas flow path through which the oxygen-containing gas introduced into the fuel cell 3 flows is provided between the inner wall 22 and the outer wall 23.

  Here, the inner wall 22 extends from the upper surface of the inner wall 22 to the side surface side of the cell stack 2, communicates with a gas flow path formed by the inner wall 22 and the outer wall 23, and enters the cell stack 2 (fuel cell 3). A reaction gas introduction member 30 for introducing the contained gas is provided. A reaction gas introduction port 25 for introducing an oxygen-containing gas into the lower end portion of the fuel cell 3 is provided at the lower end of the reaction gas introduction member 30 along the arrangement direction of the fuel cell 3.

  In FIG. 2, the reaction gas introduction member 30 is disposed so as to be positioned between two cell stacks 2 juxtaposed side by side inside the storage container 21, but depending on the number of cell stacks 2, for example, the reaction gas The introduction member 30 may be disposed so as to be sandwiched from both side surfaces of the cell stack 2. Specifically, when the cell stack apparatus 1 having only one cell stack 2 is accommodated, two reaction gas introduction members 30 can be provided and can be arranged so as to sandwich the cell stack 2 from both side surfaces. .

  Also, in the power generation chamber 24, the temperature in the module 20 is maintained at a high temperature so that the heat in the module 20 is extremely dissipated and the temperature of the fuel cell 3 (cell stack 2) is lowered and the power generation amount is not reduced. For this purpose, a heat insulating material 26 having a plate shape or a blanket shape is appropriately provided.

  The heat insulating material 26 is preferably disposed in the vicinity of the cell stack 2, and in particular, disposed on the side surface side of the cell stack 2 along the arrangement direction of the fuel cells 3, and is equivalent to the outer shape of the side surface of the cell stack 2. Or it is preferable to arrange | position the heat insulating material 26 which has a magnitude | size beyond it. Preferably, the heat insulating material 26 is disposed on both side surfaces of the cell stack 2. Thereby, it can suppress effectively that the temperature of the cell stack 2 falls. Furthermore, the oxygen-containing gas introduced from the reaction gas introduction member 30 can be suppressed from being discharged from the side surface side of the cell stack 2, and the flow of the oxygen-containing gas between the fuel cells 3 constituting the cell stack 2 can be reduced. Can be promoted.

  In this case, the heat insulating material 26 disposed on the side surface of the cell stack 2 can be sized so that the upper end thereof is in contact with the lower end of the lid-like member 8. Thereby, the oxygen-containing gas that is supplied from the outside of the fuel battery cell 3 and is not used for power generation of the fuel battery cell 3 can efficiently flow into the second reaction gas channel 16 of the lid-like member 8.

  Further, an exhaust gas inner wall 27 is provided inside the inner wall 22 along the arrangement direction of the fuel cells 3, and the exhaust gas in the power generation chamber 24 is located between the inner wall 22 and the exhaust gas inner wall 27 from above. It is an exhaust gas flow path that flows downward. The exhaust gas flow path communicates with an exhaust hole 28 provided at the bottom of the storage container 21.

  Here, the oxygen-containing gas that has flowed through the second reaction gas flow path 18 of the lid-like member 8 without being used for power generation of the fuel battery cell 3, and the first that is not used for power generation of the fuel battery cell 3. The fuel gas discharged from the reaction gas flow path 9 flows through the mixing flow path 19 of the lid-like member 8 and then is discharged from the exhaust port 18.

  Therefore, the fuel gas and the oxygen-containing gas that have not been used for power generation of the fuel battery cell 3 are combusted in the region between the reformer 29 and above the lid-like member 8. In FIG. 4, this combustion region is indicated by a one-dot chain line. Thereby, the temperature of the fuel cell 3 can be raised, and the start-up of the cell stack apparatus 1 can be accelerated. In addition, the reformer 6 disposed above the fuel cell 3 (cell stack 2) can be warmed, and the reformer 6 can efficiently perform the reforming reaction.

  Moreover, since the lid-like member 8 is arranged at the upper end of the fuel cell 3, it is possible to suppress the upper end of the fuel cell 3 from becoming excessively high temperature and to suppress deterioration and breakage of the fuel cell 3. can do. Thereby, the module 20 with improved long-term reliability can be obtained.

  Although not shown, it is preferable that an ignition device for burning the mixed gas discharged from the exhaust port 18 of the lid-like member 8 is provided above the cell stack 2. As the ignition device, for example, an ignition heater or a burner can be used.

  FIG. 5 is an exploded perspective view showing an example of the fuel cell device of the present invention in which the module 20 shown in FIG. 4 and an auxiliary machine (not shown) for operating the module 20 are housed in an outer case. It is. In FIG. 5, a part of the configuration is omitted.

  The fuel cell device 31 shown in FIG. 5 divides the interior of the exterior case composed of the support columns 32 and the exterior plate 33 into upper and lower portions by the partition plate 34, and the upper side thereof serves as a module storage chamber 35 that stores the module 20 described above. The lower side is configured as an auxiliary equipment storage chamber 36 for storing auxiliary equipment for operating the module 20. In addition, the auxiliary machine stored in the auxiliary machine storage chamber 36 is omitted.

  In addition, the partition plate 34 is provided with an air circulation port 38 for allowing the air in the auxiliary machine storage chamber 36 to flow toward the module storage chamber 35, and a part of the exterior plate 33 constituting the module storage chamber 35 includes An exhaust port 38 for exhausting air in the module storage chamber 35 is provided.

  In such a fuel cell device 31, the deterioration and breakage of the fuel cell 3 can be suppressed, and the module 20 with improved long-term reliability is housed. Therefore, the fuel cell device with improved long-term reliability. 31.

  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. It is also possible to use a fuel gas as the second reaction gas. In this case, the example in which the fuel gas is supplied to the first reaction gas flow path 9 of the fuel cell 3 and the oxygen-containing gas is supplied to the second reaction gas flow path has been shown. Alternatively, an oxygen-containing gas may be supplied to the fuel cell 3 and the fuel gas may be supplied to the outside of the fuel cell 3. In that case, what is necessary is just to set it as the fuel cell 3 of the structure which makes an inner side electrode layer the air electrode layer 11, and makes an outer side electrode layer the fuel electrode layer 12. FIG. 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 5: Conductive member 8: Lid member 9: First reaction gas channel 16: Second reaction gas channel 17, 19: Mixing channel 18: Exhaust port 20: Fuel cell module 31: Fuel cell device

Claims (5)

An inner electrode layer, a solid electrolyte layer, and an outer electrode layer are provided in this order on one main surface of a flat conductive support having a first reaction gas channel for flowing a first reaction gas therein. In addition, a plurality of fuel cells each having an interconnector provided on the other main surface are arranged in a state where a plurality of fuel cells are erected via a current collecting member therebetween, and are supplied between adjacent fuel cells. A cell stack configured to generate power in the fuel cell by using the second reaction gas and the first reaction gas, and a lower end of the fuel cell, and a first end to the fuel cell. A manifold for supplying reaction gas, and burning the first reaction gas and the second reaction gas not used for power generation of the fuel cell above the upper end of the fuel cell. Cell stacking configuration There is,
A lid-like member is disposed at the upper end of the fuel cell,
The lid-like member forms a space with each of the one-side main surface and the other-side main surface of the fuel cell, and a second reaction gas supplied between the adjacent fuel cells in the space The second reaction gas flow path for flowing, the second reaction gas flowing through the second reaction gas flow path, and the first reaction gas discharged from the first reaction gas flow path And an exhaust port for discharging the mixed gas flowing through the mixing channel and being mixed with the upper surface, and formed of a ceramic material. Cell stack device.   The cell stack device according to claim 1, wherein the mixing channel has a tapered shape toward the exhaust port.   A plurality of the lid-like members corresponding to the respective fuel cells constituting the cell stack are provided, and each lid-like member is provided at an upper end portion of each of the fuel cells constituting the cell stack. Fixing for fixing each of the lid-shaped members by sandwiching the lid-shaped members from both ends of the cell stack in the arrangement direction of the fuel cells, respectively, in a non-bonded state. The cell stack device according to claim 1, further comprising a member.   A fuel cell module comprising the cell stack device according to any one of claims 1 to 3 stored in a storage container. 5. A fuel cell device comprising: the fuel cell module according to claim 4; and an auxiliary machine for operating the fuel cell module, housed in an outer case.

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