JP5377271B2 - Cell stack device, fuel cell module and fuel cell device - Google Patents

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).

  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 raised, thereby efficiently generating power in the fuel cell. it can.

  In addition, a cell stack device (for example, a structure in which a ceramic member is mounted so as to cover the upper surface of the fuel cell in order to suppress the upper end of the fuel cell from being oxidized by the oxygen-containing gas supplied to the fuel cell. In addition, a flow path member is provided so as to cover the upper surface of the fuel battery cell for the purpose of supplying the reaction gas uniformly to a plurality of gas flow paths provided inside the fuel battery cell. A cell stack device having a configuration (see, for example, Patent Document 3) has been proposed.

JP 2007-59377 A JP 2006-127826 A 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 cell at the upper end side of the fuel cell, it is used for power generation of the fuel cell at the upper end side of the fuel cell. The temperature of the upper end of the fuel cell rises due to the combustion heat of the fuel gas that is not present, and the upper end of the fuel cell may be deteriorated or damaged.

  In addition, when the power consumption is low at night or the like, the fuel cell device generates power at a low output, so that the amount of fuel gas supplied to the fuel cell may decrease, causing a misfire in the cell stack device, There is a possibility that the fuel cell deteriorates as the operating temperature of the fuel cell device decreases.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cell stack device, a fuel cell module, and a fuel cell device that suppress deterioration and breakage of a fuel cell due to combustion heat of fuel gas that has not been used for power generation and have improved long-term reliability. It is to provide.

  A cell stack device according to the present invention includes a columnar fuel cell that includes a first reaction gas channel for flowing a first reaction gas from a lower end to an upper end and generates electric power using the first reaction gas and the second reaction gas. The first reaction gas and the second gas that are arranged and electrically connected in a state of being erected via a current collecting member and are not used for power generation on the upper end side of the fuel cell. A cell stack device comprising a cell stack configured to burn reaction gas, wherein the fuel cell supplies the first reaction gas flowing through the first reaction gas channel so as to cover an upper surface of the fuel cell. In addition, a flow path for flowing further upward from the upper end of the gas flow path is provided inside, and a flow path member including a combustion catalyst is disposed at the top.

In such a cell stack device, a flow path for flowing the first reaction gas that has flowed through the first reaction gas flow path further upward from the upper end of the fuel battery cell is formed inside so as to cover the upper surface of the fuel battery cell. Since the flow path member provided with the combustion catalyst at the top is disposed,
The first reactive gas that is not used for power generation burns near the outlet of the flow path formed inside the flow path member, and the upper end of the fuel cell is prevented from being directly warmed by the combustion heat generated by the combustion. It is possible to suppress the temperature at the upper end of the fuel cell from rising.

  Thereby, the thermal stress which arises at the upper end of a fuel cell can be relieved, and deterioration and breakage of a fuel cell can be controlled. Therefore, the long-term reliability of the fuel cell can be improved, and a cell stack device with improved long-term reliability can be obtained.

  Furthermore, when the fuel cell device operates at a low output, since the flow path member has a combustion catalyst in the upper part, it is possible to efficiently burn the first reaction gas and the second reaction gas that have not been used for power generation. It is possible to suppress the misfire of the cell stack device. Thereby, it can suppress that the temperature of a fuel battery cell falls, and can suppress deterioration of a fuel battery cell.

  In the cell stack device of the present invention, it is preferable that a combustion catalyst is provided on the upper surface of the flow path member.

  In such a cell stack device, since the combustion catalyst is provided on the upper surface of the flow path member, the first reaction gas and the second reaction gas that have not been used for power generation in the vicinity of the upper surface of the flow path member. Will burn. Thereby, it can suppress that the temperature of the upper end of a fuel cell rises, and the thermal stress which arises at the upper end of a fuel cell can be relieved. Therefore, it is possible to obtain a cell stack device in which deterioration and breakage of the fuel cell are suppressed and long-term reliability is improved.

  In the cell stack device of the present invention, it is preferable that the flow path member is provided with the combustion catalyst on a surface layer of a wall constituting the flow path.

  In such a cell stack apparatus, since the flow path member is provided with a combustion catalyst on the surface layer of the wall constituting the flow path, even when the fuel cell apparatus operates at a low output, Misfire can be suppressed. Therefore, a cell stack device with improved long-term reliability can be obtained.

  In the cell stack device of the present invention, it is preferable that the flow path member has a columnar shape and a corner portion of the outer periphery of the upper surface of the flow path member is chamfered.

  In such a cell stack apparatus, since the flow path member is columnar and the corners of the outer periphery of the upper surface of the flow path member are chamfered, thermal stress is applied to the corners of the outer periphery of the upper surface of the flow path member. Concentration can be suppressed. Thereby, deterioration of the flow path member due to thermal stress can be suppressed, and a cell stack device with improved long-term reliability can be obtained.

  In the cell stack device of the present invention, it is preferable that the flow path member is fitted to the upper end of the fuel cell.

  In such a cell stack device, since the flow path member is fitted to the upper end of the fuel cell, even when the flow path member is placed so as to cover the upper surface of the fuel cell, the flow path member is Thus, the manufacturing process of the cell stack device can be simplified.

  In the cell stack device of the present invention, it is preferable that the flow path member is formed of heat resistant ceramics.

  In such a cell stack apparatus, since the flow path member is formed of heat-resistant ceramics, it is possible to prevent the flow path member from being damaged even when combustion occurs near the upper end of the flow path member. it can. Thereby, a cell stack device with improved long-term reliability can be obtained.

  Moreover, it is preferable that the cell stack apparatus of the present invention includes a manifold for fixing the lower end side of the fuel cell and supplying the first reaction gas to the fuel cell.

  In such a cell stack device, since the lower end side of the fuel cell is fixed and a manifold for supplying the first reaction gas to the fuel cell is provided, the first reaction gas is reliably supplied to the fuel cell. Can be supplied. Thereby, even when the fuel cell device operates at a low output, misfiring of the cell stack device can be suppressed, and a cell stack device with improved long-term reliability can be obtained.

  The fuel cell module of the present invention is characterized in that the above-described cell stack device is housed in a housing container, so that a fuel cell module with improved long-term reliability can be obtained.

  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.

  The cell stack device of the present invention has a flow path for flowing the first reaction gas before flowing through the first reaction gas flow path from the upper end of the fuel battery cell further upward so as to cover the upper surface of the fuel battery cell. Since the flow path member provided with the combustion catalyst is disposed at the top, the first reaction gas that has not been used for power generation is formed near the outlet of the flow path formed inside the flow path member. It will burn, and it can control that the upper end of a fuel cell is directly warmed by the combustion heat which arose by combustion, and it can control that the temperature in the upper end of a fuel cell rises.

  Thereby, the thermal stress which arises at the upper end of a fuel cell can be relieved, and deterioration and breakage of a fuel cell can be controlled. Therefore, the long-term reliability of the fuel cell can be improved, and a cell stack device with improved long-term reliability can be obtained.

  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 the present invention is shown, (a) is a side view schematically showing the cell stack apparatus, (b) is a part of the fuel cell of (a), with the flow path member removed. It is a top view extracted and shown. It is a schematic perspective view which extracts and shows the fuel cell and flow path member in an example of the cell stack apparatus of this invention. It is a figure which shows the fuel cell shown in FIG. 2, and a flow-path member, (a) is an AA 'sectional view, (b) is a top view. It is a schematic perspective view which extracts and shows the fuel cell and flow-path member in other examples of the cell stack apparatus of this invention. FIG. 5 is a cross-sectional view of the fuel cell shown in FIG. 4 and a flow path member taken along line BB ′. It is a schematic perspective view which extracts and shows the fuel cell and flow path member in another example of the cell stack apparatus of this invention. It is CC 'sectional view taken on the line of the fuel cell shown in FIG. 6, and a flow-path member. 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, and (b) is a partial fuel cell of the cell stack device 1 of (a). FIG. 5 is an enlarged plan view showing a state in which a flow path member is removed, and shows a portion surrounded by a dotted line frame shown in FIG. In the following drawings, the same numbers are assigned to the same members.

  Here, the cell stack device 1 has a first reaction gas flow path 9 inside, and has a pair of opposed flat surfaces on one flat surface of a conductive support 10 that has a generally elliptical cylindrical shape. The inner electrode layer 11, the solid electrolyte layer 12, and the outer electrode layer 13 are laminated in this order, and at the portion of the other flat surface where the outer electrode layer 13 and the solid electrolyte layer 12 are not formed. By disposing the columnar (hollow flat plate) fuel cells 3 formed by stacking the connectors 14 in a state of being erected via the current collecting member 4 therebetween, the fuel cells 3 are electrically connected in series. A cell stack 2 connected to is provided.

  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 a portion located between adjacent slits in the vertical direction serves as a current collecting piece (not shown). The current collecting pieces formed in the longitudinal direction of the current collecting member 4 are alternately arranged so as to be joined to the fuel cell 3 on one side or the fuel cell 3 on the other side. The space between the current collecting piece joined to the fuel cell 3 on one side and the current collecting piece joined to the fuel cell 3 on the other side is a second for flowing the second reaction gas upward from below. The reaction gas channel 19 is formed.

  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 side of each fuel cell 3 constituting the cell stack 2 has a glass sealing material (not shown) on the manifold 7 for supplying the first reaction gas to the fuel cell 3 via the first reaction gas flow path 9. Z)).

  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.

  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 direction in which the fuel cells 3 are arranged to draw out current generated by power generation of the cell stack 2 (fuel cells 3). A current extraction unit 6 is provided.

  In such a cell stack apparatus 1, the fuel gas discharged from the first reaction gas flow path 9 and not used for power generation of the fuel battery cell 3 is combusted on the upper end side of the fuel battery cell 3. Thus, 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, the flow path member 8 is disposed so as to cover the upper surface of each fuel cell 3. The flow path 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 ones 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

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 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, particularly 30 to 50. % Is preferable. 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 from the viewpoint of gas leakage prevention and electric 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 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 cell stack apparatus 1 described above, the first reaction gas (fuel gas) that is discharged from the first reaction gas flow path 9 on the upper end side of the fuel cell 3 and is not used in the power generation of the fuel cell 3. When the fuel cell is burned, the temperature at the upper end of the fuel cell 3 rises excessively, and a part (particularly the upper end) of the fuel cell 3 may be deteriorated or damaged.

  Therefore, in the cell stack device 1 of the present invention, the flow path member 8 is disposed at the upper end of the fuel cell 3 so as to cover the upper surface of the fuel cell 3.

  FIG. 2 is a perspective view schematically showing the fuel battery cell 3 and the flow path member 8 constituting the cell stack device 1, and FIG. 3 is a perspective view of the fuel battery cell 3 and the flow path member shown in FIG. 8A is a sectional view taken along line AA ′, and FIG. 8B is a plan view.

  The flow path member 8 has a quadrangular shape, and a flow path member flow path 16 for flowing the first reaction gas (fuel gas) upward is formed therein, and the flow path member flow at the upper surface and the upper end of the fuel cell 3 is formed. A combustion catalyst 17 is provided on the surface layer of the wall constituting the passage 16. And the flow path member 8 is arrange | positioned so that the upper surface of the fuel cell 3 may be covered through an adhesive material (not shown) so that the flow path member flow path 16 and the 1st reaction gas 9 may connect. Yes. In FIG. 2, the flow path member 8 is connected to the upper surface of the fuel cell 3.

  The length of the flow path member 8 in the width direction of the fuel cell 3 (hereinafter referred to as the width of the flow path member 8) is preferably equal to or longer than the width of the fuel cell 3, and at least the fuel cell 3 It is preferable that the length be sufficient to cover all of the plurality of first reaction gas channels 9 provided. As will be described in detail later, the length of the flow path member 8 in the arrangement direction of the fuel cells 3 (hereinafter referred to as the thickness of the flow path member 8) is the length in the arrangement direction of the fuel cells 3 (fuel). The thickness of the flow path member 8 is preferably adjusted so that the second reaction gas (air) can flow between the adjacent flow path members 8. The length of the flow path member 8 in the longitudinal direction of the fuel cell 3 (hereinafter referred to as the height of the flow path member 8) may be about 1 to 3 cm. What is necessary is just to set suitably the width | variety, thickness, and height of the flow-path member 8 based on the structure of a cell stack apparatus.

  In the flow path member 8 shown in FIG. 3, the flow path member flow path 16 is provided so as to communicate with all of the plurality of first reaction gas flow paths 9 provided in the fuel cell 3. The member 8 has an elliptical shape having a major axis in the width direction of the flow path member 8 in plan view.

  Since the flow path member 8 includes the combustion catalyst 17 in the upper part and is disposed so as to cover the upper surface of the fuel cell 3, combustion that has conventionally occurred near the upper end (upper end side) of the fuel cell 3 is performed. It occurs near the upper end of the flow path member 8. Thereby, it can suppress that the temperature of the upper end of the fuel cell 3 rises excessively, and the thermal stress which arises at the upper end of the fuel cell 3 can be relieved. Therefore, deterioration and breakage of the fuel cell 3 (particularly the upper end) can be suppressed, and the cell stack device 1 with improved long-term reliability can be obtained.

  Here, when the power consumption is low at night or the like, the fuel cell device operates at a low output, so the amount of fuel gas supplied to the fuel cell 3 decreases (the amount of fuel gas not used for power generation). There is a risk that misfiring may occur in the cell stack device 1 and the fuel cell 3 may deteriorate as the operating temperature of the fuel cell device decreases.

  The cell stack device 1 of the present invention has a flow path member 8 that is disposed so as to cover the upper surface and the upper surface of the fuel cell 3 and that has a combustion catalyst 17 on the surface layer of the wall constituting the flow path member flow path 16. Thus, even when the amount of fuel gas supplied to the fuel cell 3 is small, combustion can be efficiently caused by the combustion catalyst 17 and the occurrence of misfire in the cell stack device 1 can be suppressed. .

  Here, the upper end side of the flow path member 8 indicates the surface layer of the wall constituting the flow path member flow path 16 in the vicinity of the upper surface of the flow path member 8, the side surface, or the upper end of the fuel cell 3. In the cell stack device 1 of the present invention, the side layer or the surface layer of the wall constituting the flow path member flow path 16 at the upper end of the fuel cell 3 is the flow of the wall constituting the respective side face or flow path member flow path 16. An area of about 1 cm from the upper end of the path member 8 is shown, but may be set as appropriate according to the configuration of the cell stack device so that the temperature at the upper end of the fuel cell 3 does not rise excessively.

  Since the flow path member 8 is preferably made of a heat-resistant material, and preferably has a low thermal conductivity, ceramics or the like is preferably used. Examples of the ceramic material forming the flow path member 8 include ceramic materials such as silica, alumina, magnesia, and zirconia. In addition, these ceramic materials can also be used as partially stabilized ceramic materials in which rare earth elements are dissolved or stabilized ceramic materials.

  Moreover, since the flow path member 8 is connected to the fuel battery cell 3, it is preferable to have insulation. Thereby, even when the flow path members 8 connected to the adjacent fuel cells 3 are in contact with each other, an electrical short circuit can be prevented.

  In order for the flow path member 8 to have insulating properties, the flow path member 8 may be made of an insulating material, or a known insulating coating that forms an alumina coating may be applied. Since the combustion catalyst 17 described later has conductivity, it is preferable to apply an insulating coating to a portion (side surface or the like) where the flow path member 8 may come into contact with the outside.

  Furthermore, since it is connected to the fuel cell 3, it is preferable that the thermal expansion coefficient of the flow path member 8 and the thermal expansion coefficient of the fuel cell 3 (particularly, the conductive support 10) are made closer to each other. By reducing the difference in thermal expansion between the flow path member 8 and the conductive support 10, stress generated near the connection surface between the flow path member 8 and the fuel cell 3 can be relieved. Damage can be suppressed.

  The adhesive for connecting the flow path member 8 and the fuel cell 3 is not particularly limited as long as it can withstand use at high temperatures, but borosilicate glass and soda glass are employed. The adhesive is applied to the adhesive surface by masking the first reaction gas channel 9 and the channel member channel 16 so as not to block the first reaction gas channel 9 and the channel member channel 16. That's fine.

  Examples of the combustion catalyst 17 include platinum, rhodium, and palladium. By providing the combustion catalyst 17 in the flow path member 8, the activity of the oxygen-containing gas and the hydrogen-containing gas can be improved, and combustion can be performed efficiently.

  As a method of providing the combustion catalyst 17 on the upper end side of the flow path member 8, fine particles such as platinum and a solution are mixed, and this mixed solution is impregnated with a region where the combustion catalyst 17 of the flow path member 8 is to be provided, and then heat treated. Can be done. Thereby, the combustion catalyst 17 can be easily provided in a predetermined region of the flow path member 8. Note that the combustion catalyst layer 17 may be provided on a thin layer by plating or coating. Thereby, the quantity of the combustion catalyst 17 to be used can be reduced, and the cost of the flow path member 8 can be reduced.

  In addition, although the diameter of the flow path member flow path 16 shown in FIG. 3 is constant regardless of the height of the flow path member 8, the flow path member flow path 16 becomes higher. It is good also as a tapering shape where a diameter becomes small as it goes. In that case, since the area of the upper surface of the flow path member 8 can be increased and a large number of combustion catalysts can be provided, combustion can be caused more near the upper end of the flow path member 8.

  4 is a perspective view schematically showing the fuel cell 3 and the flow path member 18 constituting the cell stack device 1, and FIG. 5 is a perspective view schematically showing the fuel cell 3 and the flow path member shown in FIG. FIG.

  The flow path member 18 shown in FIGS. 4 and 5 has a chamfered corner portion at the outer periphery at the upper end of the flow path member 8 shown in FIG. And the combustion catalyst 17 is provided in the surface layer of the wall which comprises the flow path member flow path 16 in the upper surface, the upper surface vicinity of each side surface, and the upper end of the fuel cell 3.

  Since the channel member 18 is chamfered at the corners of the outer periphery at the upper end, it is possible to prevent thermal stress from concentrating on the corners of the outer periphery at the upper end of the channel member 18, and the channel member 18 is damaged. Can be suppressed.

  Here, the fuel cell module (not shown) of the present invention supplies the fuel gas to the first reaction gas channel (fuel gas channel) provided inside the fuel cell 3 and introduces the second reaction gas. A second reaction gas (oxygen-containing gas) is supplied to a lower portion between the fuel cells 3 from a member (not shown). The oxygen-containing gas supplied downward between the fuel cells 3 flows from below to above the second reaction gas channel (oxygen-containing gas channel) 19 formed between the fuel cells 3, and the channel member 18 is sent to the upper end side. The fuel gas and the oxygen-containing gas react at the upper end side of the flow path member 18 to warm the fuel cell module.

  In the cell stack device 1 of the present invention shown in FIG. 5, a plurality of fuel cells 3 are arranged at a predetermined interval, and the fuel cells 3 are electrically connected via a current collecting member (not shown). Connected in series. As described above, the space between one current collecting piece (not shown) connected to one fuel battery cell 3 and the other current collecting piece connected to the other fuel battery cell 3 is the first. Two reaction gas channels 19 are formed. In FIG. 5, a portion surrounded by a one-dot chain line is a second reaction gas channel 19.

  The flow path member 18 of the present invention shown in FIG. 5 has a chamfered outer peripheral corner at the upper end, so that the oxygen-containing gas flowing through the second reaction gas flow path 19 is at the outlet of the flow path member flow path 16. In the case where the fuel cell operates at a low output, the misfire can be suppressed even when the amount of the fuel gas supplied to the fuel cell 3 and the amount of the oxygen-containing gas are small. Can do. Thereby, it can suppress that the temperature of the fuel cell 3 falls, and deterioration of the fuel cell 3 can be suppressed.

  In addition, in the flow path member 18, although the example which carried out C surface processing was shown as a chamfering method, you may chamfer a corner | angular part by the combination of R surface processing or C surface processing, and R surface processing. Moreover, although the example which chamfered only the outer periphery in an upper end was shown, what is necessary is just to perform chamfering suitably also in another part as needed.

  Moreover, the 2nd reaction gas flow path 19 shows the area | region corresponding to the height of the fuel cell 3 between the adjacent fuel cells 3, and is an area | region where the current collection member (not shown) is provided.

  6 is a perspective view schematically showing an extracted fuel cell 3 and a flow path member 20 in still another example of the cell stack device of the present invention, and FIG. 7 is a fuel cell shown in FIG. 3 is a cross-sectional view taken along the line CC ′ of the line 3 and the flow path member 20.

  In the flow path member 20 shown in FIG. 6, a plurality of flow path member flow paths 16 are formed so as to correspond to the respective first reaction gas flow paths 9 provided in the fuel cell 3. The flow path member 20 and the upper end of the fuel cell 3 are fitted together. Thereby, the fuel cell 3 and the flow path member 20 can be easily connected, and the cell stack apparatus 1 can be created easily.

  Further, the flow path member 20 and the fuel battery cell 3 can be easily connected by fitting the flow path member 20 to the upper end of the fuel battery cell 3 and connecting them. Therefore, even when the flow path member 20 is damaged, it can be easily replaced.

  Furthermore, since the upper end of the fuel cell 3 and the flow path member 20 are fitted together, the connection between the fuel battery cell 3 and the flow path member 20 can be strengthened. It is possible to prevent the fuel gas from leaking from between 20. Therefore, even when the fuel cell device operates at a low output and a small amount of fuel gas is supplied to the fuel cell 3, misfire can be suppressed.

  Further, since the connection between the fuel cell 3 and the flow path member 20 becomes strong by fitting and connecting the flow path member 20 and the upper end of the fuel cell 3, the fuel battery cell 3 and the flow path Even when stress is generated in the member 20, it is possible to prevent the fuel cell 3 and the flow path member 20 from being peeled off or damaged.

  In the case where the flow path member 20 is made of a heat-resistant ceramic material, in the case where a plurality of flow path member flow paths 16 are provided, the flow path member 20 can be easily formed by extrusion, so that a plurality of flow path members 20 can be easily formed. The flow path member 20 provided with the flow path member flow path 16 can be produced. Furthermore, the diameter of the flow path member flow path 16 is preferably equal to or larger than the diameter of the first reaction gas flow path 9. Thereby, it is possible to suppress the fuel gas from becoming difficult to flow in the first reaction gas flow path 9.

  Even when the fuel cell 3 and the flow path member 20 are fitted and connected, they can be connected using the above-described adhesive (not shown). For example, the adhesive is preferably applied so as not to block the outlet of the first reactive gas channel 9 and the inlet of the channel member channel 16. By fitting and connecting the fuel cell 3 and the flow path member 20, the adhesion area can be increased and the fuel cell 3 and the flow path member 20 can be more firmly connected. As a method of applying an adhesive so as not to block the outlet of the first reactive gas channel 9 and the inlet of the channel member channel 16, the outlet of the first reactive gas channel 9 and the channel member channel 16 In addition to masking the inlet and applying the adhesive, the adhesive passes through the first reaction gas channel 9 and the channel member channel 16 by gas suction or the like after the fuel cell 3 and the channel member 20 are connected. May be removed.

  In addition, although the example which provided the columnar flow-path member 20 was shown, the flow-path member may have a shape which is not columnar. For example, the flow path member may be provided by a plate member or the like. Even in this case, the thermal stress generated at the upper end of the fuel cell 3 can be relaxed, and the long-term reliability of the cell stack can be improved.

  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 fuel gas discharged from the first reaction gas flow path 9 of the fuel battery cell 3 and the oxygen-containing gas are combusted on the upper end side of the fuel battery cell 3, thereby increasing the temperature of the fuel battery 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 side of the fuel battery cell 3 so that the fuel battery cell 3 (cell stack 2) is positioned above the fuel battery cell 3. The arranged reformer 27 can be efficiently warmed. 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.

  Moreover, although the example which provided the flow-path member for every some fuel cell was shown, it is not necessary to provide a flow-path member for every some fuel cell, for example, integrating each flow-path member, You may provide the flow-path member extended in the sequence direction of a fuel cell. In that case, the number of members constituting the cell stack can be reduced, and the manufacturing process can be simplified.

1: Cell stack device 2: Cell stack 3: Fuel cell 5: Conductive members 8, 18, 20: Channel member 9: First reaction gas channel 16: Channel member channel 17: Combustion catalyst 19: Second Reaction gas flow path 25: Fuel cell module 30: Fuel cell device

Claims (9)

A plurality of columnar fuel cells each having a first reaction gas flow path for flowing the first reaction gas from the lower end to the upper end and generating electric power with the first reaction gas and the second reaction gas are disposed via a current collecting member. The first reaction gas and the second reaction gas that are not used for power generation are combusted on the upper end side of the fuel cell, and are arranged and electrically connected in a stand-up state. A cell stack device comprising a cell stack,
A flow path for allowing the first reaction gas that has flowed through the first reaction gas flow path to flow further upward from the upper end of the fuel battery cell so as to cover the upper surface of the fuel battery cell is provided inside, and at the top A cell stack device, wherein a flow path member including a combustion catalyst is disposed.   The cell stack device according to claim 1, wherein the combustion catalyst is provided on an upper surface of the flow path member.   The cell stack device according to claim 1, wherein the flow path member is provided with the combustion catalyst on a surface layer of a wall constituting the flow path.   The cell stack device according to any one of claims 1 to 3, wherein the flow path member has a columnar shape, and a corner portion of an outer periphery of the upper surface of the flow path member is chamfered.   The cell stack device according to claim 1, wherein the flow path member is fitted to an upper end of the fuel battery cell.   6. The cell stack device according to claim 1, wherein the flow path member is made of heat resistant ceramics.   The cell stack device according to claim 1, further comprising a manifold for fixing a lower end side of the fuel battery cell and supplying the first reaction gas to the fuel battery cell.   A fuel cell module comprising the cell stack device according to claim 1 in a storage container.   9. A fuel cell device comprising: the fuel cell module according to claim 8; and an auxiliary machine for operating the fuel cell module, housed in an outer case.

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