JP2014191994A - Cell stack device, fuel cell module and fuel cell apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cell stack device improved in long-term reliability, a fuel cell module and a fuel cell apparatus.SOLUTION: A cell stack device 12 comprises a plurality of fuel cells 3 configured to generate power with fuel gas and oxygen containing gas, to include a gas flow passage 36 penetrating the inside in a length direction and to combust the fuel gas which is not used for power generation, at an upper end side; and a manifold 4 communicating to the gas flow passage 36 for supplying fuel gas to the gas flow passage 36. Since the fuel cells 3 are disposed in such a manner that upper ends of the gas flow passages 36 are located at different positions in a height direction, accidental ignition can be efficiently prevented and re-ignition can be easily implemented.

Description

  The present invention relates to a cell stack device, a fuel cell module, and a fuel cell device.

  In recent years, as a next-generation energy, a fuel cell module in which a fuel cell capable of obtaining electric power using a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air) is stored in a storage container, or a fuel cell Various fuel cell devices in which a module is housed in an outer case have been proposed (see, for example, Patent Document 1).

  In such a fuel cell device, it is known that fuel gas that has not been used for power generation is burned above the fuel cell, so that the temperature of the fuel cell is maintained at a high temperature and efficient power generation is performed. ing.

  In such a fuel cell, misfiring may occur at the time of starting the fuel cell device, sudden fluctuations in load, or at low output such as at night. In this case, the power generation efficiency of the fuel cell is reduced. May decrease. Therefore, a configuration in which a flow path member is provided at the upper end of the fuel cell in order to suppress the misfire described above is illustrated.

JP 2007-59377 A JP 2011-134542 A

  However, in the configuration of Patent Document 2 described above, each fuel cell needs to be provided with a flow path member, and there is a problem that the configuration becomes complicated, and a fuel cell device that can suppress misfire with a simpler configuration is required. ing.

  Therefore, an object of the present invention is to provide a cell stack device, a fuel cell module, and a fuel cell device that can suppress misfire and have improved long-term reliability.

  The cell stack device of the present invention generates power with fuel gas and oxygen-containing gas, and has a gas flow path penetrating the inside in the longitudinal direction, and burns the fuel gas that has not been used for power generation at the upper end side. A plurality of fuel battery cells having a configuration, and a manifold that communicates with the gas flow path and supplies fuel gas to the gas flow path. The fuel battery cell has an upper end in the height direction of the gas flow path. It is arrange | positioned so that it may become a different position.

  Further, the fuel cell module of the present invention contains the above-mentioned cell stack device in a storage container, and the fuel cell in the cell stack device is located at the lowest position in the gas flow path. The gas flow path is arranged so as to be located on the high temperature side.

  Furthermore, the fuel cell device of the present invention is characterized in that the fuel cell module is housed in an outer case.

  The cell stack device of the present invention includes a plurality of fuel cells having gas passages penetrating the inside in the longitudinal direction, and the fuel cells are arranged such that the upper ends of the gas passages are at different positions in the height direction. Therefore, even if a misfire occurs in the gas flow path whose upper end is located above, if combustion occurs in the gas flow path whose upper end is located below, the combustion heat or combustion flame Since the misfired gas flow path can be re-ignited, a cell stack device with improved long-term reliability can be obtained.

  Further, the fuel cell module of the present invention is configured such that the cell stack device is housed in a housing container, and the fuel cell in the cell stack device is located at the lowest position among the gas flow channels. Is disposed so as to be located on the high temperature side, misfire can be suppressed, and a fuel cell module with improved long-term reliability can be obtained.

  Furthermore, the fuel cell device of the present invention can be a fuel cell device with improved long-term reliability since the fuel cell module is housed in an outer case.

It is an external appearance perspective view which shows a fuel cell module provided with an example of the cell stack apparatus of this embodiment. It is sectional drawing of the fuel cell module shown in FIG. (A) is a side view of the cell stack device shown in FIG. 1, and (b) is a plan view showing a part of the cell stack device shown in (a). It is an external appearance perspective view which shows another example of the cell stack apparatus of this embodiment. It is sectional drawing which shows another example of the fuel cell module of this embodiment. It is a disassembled perspective view which shows roughly an example of the fuel cell apparatus of this embodiment.

  FIG. 1 is an external perspective view showing an example of a fuel cell module (hereinafter sometimes referred to as a module) according to the present embodiment, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. FIG. 3B is a plan view showing a part of the cell stack device shown in FIG. In the following drawings, the same numbers are assigned to the same members.

  In the module 1 shown in FIG. 1, the fuel cells 3 having fuel gas passages (not shown) through which the fuel gas flows are arranged in a row in the storage container 2, Adjacent fuel cells 3 are electrically connected in series via a current collecting member (not shown in FIG. 1), and the lower end of the fuel cells 3 is connected to an insulating bonding material such as a glass sealing material. A cell stack device 12 including two cell stacks 5 fixed to the manifold 4 by a not shown is housed. A reformer 6 for generating fuel gas to be supplied to the fuel cell 3 is disposed above the cell stack 5. At both ends of the cell stack 5, conductive members having electrical lead portions for collecting and drawing the electricity generated by the power generation of the cell stack 4 (fuel cell 3) to the outside are disposed ( Not shown). Although FIG. 1 shows the case where the cell stack device 12 includes two cell stacks 5, the number can be changed as appropriate. For example, even if only one cell stack 5 is provided. Good. Further, the cell stack device 12 may include the reformer 6.

In FIG. 1, the fuel cell 3 is a hollow flat plate type having a plurality of fuel gas passages through which fuel gas flows in the longitudinal direction. A fuel electrode layer is formed on the surface of the support having the fuel gas passages. 1 illustrates a solid oxide fuel cell 3 in which a solid electrolyte layer and an oxygen electrode layer are sequentially laminated. An oxygen-containing gas flows between the fuel cells 3. The configuration of the fuel cell 3 will be described later.

  In the fuel cell device of the present embodiment, the fuel cell 3 may be a solid oxide fuel cell, and may be, for example, a flat plate shape or a cylindrical shape. It can be changed as appropriate.

  Further, in the reformer 6 shown in FIG. 1, fuel gas is generated by reforming raw fuel such as natural gas or kerosene supplied through the raw fuel supply pipe 10. The reformer 6 preferably has a structure capable of performing steam reforming, which is an efficient reforming reaction. The reformer 6 reforms the raw fuel into fuel gas, and a vaporizer 7 for vaporizing water. And a reforming unit 8 in which a reforming catalyst (not shown) is disposed. The fuel gas generated by the reformer 6 is supplied to the manifold 4 via the fuel gas flow pipe 9 and is supplied from the manifold 4 to the fuel gas flow path provided inside the fuel cell 3.

  FIG. 1 shows a state in which a part (front and rear surfaces) of the storage container 2 is removed and the cell stack device 12 stored inside is taken out rearward. Here, in the module 1 shown in FIG. 1, the cell stack device 12 can be slid and stored in the storage container 2.

  The storage container 2 is disposed between the cell stacks 5 juxtaposed to the manifold 4, so that the oxygen-containing gas flows from the lower end portion toward the upper end portion of the fuel cell 3. A contained gas introduction member 11 is disposed.

  As shown in FIG. 2, the storage container 2 constituting the module 1 has a double structure having an inner wall 13 and an outer wall 14, and an outer frame of the storage container 2 is formed by the outer wall 14, and a cell stack is formed by the inner wall 13. A power generation chamber 15 that houses the device 12 is formed. Further, in the storage container 2, an oxygen-containing gas flow path 21 through which the oxygen-containing gas introduced into the fuel cell 3 circulates between the inner wall 13 and the outer wall 14.

  Here, the storage container 2 is provided with an oxygen-containing gas inlet (not shown) for allowing oxygen-containing gas to flow into the upper end side from the upper part of the storage container 2 and a flange portion 26, and fuel at the lower end portion. An oxygen-containing gas introduction member 11 provided with an oxygen-containing gas outlet 16 for introducing an oxygen-containing gas at the lower end of the battery cell 3 is inserted through the inner wall 13 and fixed. A heat insulating member 17 is disposed between the flange portion 26 and the inner wall 13.

  In FIG. 2, the oxygen-containing gas introduction member 11 is disposed so as to be positioned between two cell stacks 5 juxtaposed inside the storage container 2, but is appropriately disposed depending on the number of cell stacks 5. can do. For example, when only one cell stack 5 is stored in the storage container 2, two oxygen-containing gas introduction members 11 can be provided and disposed so as to sandwich the cell stack 5 from both side surfaces.

  Also, in the power generation chamber 15, the temperature in the module 1 is maintained at a high temperature so that the heat in the module 1 is extremely dissipated and the temperature of the fuel cell 3 (cell stack 5) decreases and the power generation amount does not decrease. A heat insulating member 17 is appropriately provided.

The heat insulating member 17 is preferably disposed in the vicinity of the cell stack 5. In particular, the heat insulating member 17 is disposed on the side surface side of the cell stack 5 along the arrangement direction of the fuel cell 3, and the fuel cell unit on the side surface of the cell stack 5. It is preferable to arrange the heat insulating member 17 having a width equal to or greater than the width along the three arrangement directions. In addition, it is preferable to arrange the heat insulating members 17 on both side surfaces of the cell stack 5. Thereby, it can suppress effectively that the temperature of the cell stack 5 falls. Furthermore, the oxygen-containing gas introduced from the oxygen-containing gas introduction member 11 can be suppressed from being discharged from the side surface side of the cell stack 5, and the flow of the oxygen-containing gas between the fuel cells 3 constituting the cell stack 5. Can be promoted. In the heat insulating members 17 arranged on both side surfaces of the cell stack 5, the flow of the oxygen-containing gas supplied to the fuel cell 3 is adjusted, and the longitudinal direction of the cell stack 5 and the stacking direction of the fuel cell 3 are adjusted. An opening 18 is provided for reducing the temperature distribution at.

  Further, an exhaust gas inner wall 19 is provided inside the inner wall 13 along the arrangement direction of the fuel cells 3, and the exhaust gas in the power generation chamber 15 is located between the inner wall 13 and the exhaust gas inner wall 19 from above. The exhaust gas flow path 22 flows downward. The exhaust gas passage 22 communicates with the exhaust hole 20 provided at the bottom of the storage container 2. A heat insulating member 17 is also provided on the cell stack 5 side of the exhaust gas inner wall 19.

  As a result, the exhaust gas generated with the operation of the module 1 (during start-up processing, power generation, and stop processing) flows through the exhaust gas passage 22 and is then exhausted from the exhaust hole 20. The exhaust hole 20 may be formed by cutting out a part of the bottom of the storage container 2 or may be formed by providing a tubular member.

  Note that a thermocouple 24 for measuring the temperature in the vicinity of the cell stack 5 is provided inside the oxygen-containing gas introduction member 11, and the temperature measuring portion 23 is the central portion in the longitudinal direction of the fuel cell 3 and the fuel cell. 3 are arranged so as to be located at the center in the arrangement direction.

  Further, in the module 1 having the above-described configuration, the fuel gas and the oxygen-containing gas that are not used for power generation discharged from the fuel gas flow path in the fuel cell 3 are transferred to the upper end of the fuel cell 3 and the reformer 6. It is possible to raise and maintain the temperature of the fuel cell 3 by burning between the two. In addition, the reformer 6 disposed above the fuel cell 3 (cell stack 5) can be warmed, and the reformer 6 can efficiently perform the reforming reaction. During normal power generation, the temperature in the module 1 is about 500 to 800 ° C. with the combustion and power generation of the fuel cell 3.

  As shown in FIG. 2, in the cell stack device 12 of the present embodiment, the fuel cells 3 are arranged so that the upper ends of the gas flow paths are at different positions in the height direction. Will be described later.

  FIG. 3 shows an example of the cell stack device 12 of the present embodiment shown in FIG. 1, wherein (a) is a side view schematically showing the cell stack device 12, and (b) is a cell of (a). It is the top view to which a part of stack apparatus 12 was expanded, and it has extracted and shown the part enclosed with the dotted-line frame shown by (a). In addition, in (b), in order to clarify, the part corresponding to the part enclosed with the dotted-line frame shown by (a) is shown with the arrow.

  In the cell stack device 12 shown in FIG. 3, a plurality of fuel cells 3 are arranged in a state where they are erected between the fuel cells 3 via current collecting members 38, and are electrically connected in series. The cell stacks 5 are connected to each other, and the lower end portion of each fuel cell 3 is fixed to a manifold 4 that supplies fuel gas to the fuel cell 3.

  In addition, the cell stack device 12 is a conductive member having a lower end fixed to the manifold 4 so as to sandwich the cell stack 5 from both ends in the arrangement direction of the fuel cells 3 via the current collecting member 38 disposed at the end. 27.

The conductive member 27 shown in FIG. 3 (a) is 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 5 (fuel cells 3). A current drawing unit 28 is provided.

  Hereinafter, the configuration of the fuel cell 3 will be described using the fuel cell 3 shown in FIG.

  The fuel battery cell 3 includes a fuel electrode layer 31 and a solid electrolyte on a flat surface on one side of a columnar conductive support 35 having a pair of opposed flat surfaces (hereinafter sometimes abbreviated as a support 35). The layer 32 and the oxygen electrode layer 33 are laminated in order. In addition, in the site | part by which the fuel electrode layer 31, the solid electrolyte layer 32, and the oxygen electrode layer 33 were laminated | stacked in this order, it produces electric power with the fuel gas and oxygen-containing gas which are supplied to the fuel cell 3.

  Furthermore, an interconnector 34 is provided on the other flat surface of the fuel cell 3, and a plurality of fuel gas passages 36 for flowing fuel gas are provided inside the support 35.

  Also, a P-type semiconductor layer 37 can be provided on the outer surface (upper surface) of the interconnector 34, and FIG. 3B shows an example in which the P-type semiconductor layer 37 is provided. By connecting the current collecting member 38 to the interconnector 34 via the P-type semiconductor layer 37, the contact between the two becomes an ohmic contact, the potential drop can be reduced, and the deterioration of the current collecting performance can be effectively avoided. It becomes.

  Alternatively, the support 35 may also serve as the fuel electrode layer 31, and the fuel cell 3 may be configured by sequentially laminating the solid electrolyte layer 32 and the oxygen electrode layer 33 on one surface thereof.

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

As the fuel electrode layer 31, generally known materials can be used, and porous conductive ceramics, for example, ZrO ₂ in which a rare earth element is dissolved (referred to as stabilized zirconia, including partially stabilized zirconia). And Ni and / or NiO.

The solid electrolyte layer 32 has a function as an electrolyte that bridges 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 oxygen electrode layer 33 is not particularly limited as long as it is generally used. For example, the oxygen electrode layer 33 can be formed of a conductive ceramic made of a so-called ABO ₃ type perovskite oxide. The oxygen electrode layer 33 is required to have gas permeability, and the open porosity is preferably 20% or more, particularly preferably in the range of 30 to 50%.

The interconnector 34 can be formed from conductive ceramics, but since it is in contact with a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air, etc.), it is necessary to have reduction resistance and oxidation resistance. Therefore, a lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) is preferably used. The interconnector 34 must be dense in order to prevent leakage of fuel gas flowing through the gas flow path 17 formed in the support 35 and oxygen-containing gas flowing outside the fuel cell 3, and 93 It is preferable to have a relative density of 95% or more, particularly 95% or more.

The support 35 is required to be gas permeable in order to allow the fuel gas to pass to the fuel electrode layer 31 and to be conductive in order to collect current via the interconnector 34. Therefore, as the support 35, 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.

Incidentally, when the support 35 is produced by cofiring with the fuel electrode layer 31 or the solid electrolyte layer 32 in producing the fuel battery cell 3, it is necessary to specify an iron group metal component such as Ni and Y ₂ O ₃ etc. The support 35 is preferably formed from a rare earth oxide. Further, the support 35 preferably has an open porosity of 30% or more, particularly 35 to 50% in order to have fuel gas permeability, and its conductivity is preferably 50 S / cm or more, preferably Is preferably 300 S / cm or more, particularly 440 S / cm or more.

Furthermore, as the P-type semiconductor layer 37, a layer made of a perovskite oxide of a transition metal can be exemplified. Specifically, those having higher electron conductivity than the lanthanum chromite perovskite oxide (LaCrO ₃ ) constituting the interconnector 34, for example, LaSrCoFeO ₃ system in which Sr (strontium) and La (lanthanum) coexist at the A site. It is preferably composed of at least one of oxide (for example, LaSrCoFeO ₃ ), LaMnO ₃ -based oxide (for example, LaSrMnO ₃ ), LaFeO ₃ -based oxide (for example, LaSrFeO ₃ ), and LaCoO ₃ -based oxide (for example, LaSrCoO ₃ ). In particular, it is particularly preferable to use LaSrCoFeO ₃ -based oxide from the viewpoint of high electrical conductivity at an operating temperature of about 600 to 1000 ° C. In addition, it is preferable that the thickness of such P-type semiconductor layer 37 in which Fe and Mn may exist together with Co at the B site is generally in the range of 30 to 100 μm.

  Each fuel cell 3 is electrically connected in series via a current collecting member 38. The current collecting member 38 can be constituted by a member made of an elastic metal or alloy or a member obtained by adding a required surface treatment to a felt made of metal fiber or alloy fiber.

  In addition, since it is exposed to a high-temperature oxidizing atmosphere during power generation of the fuel cell device, it is preferably produced using an alloy containing Cr. Furthermore, it is preferable to coat a part of the surface of the current collecting member 38, preferably the whole with a perovskite oxide containing a rare earth element.

  The length in the longitudinal direction and the length in the width direction of the current collecting member 38 are preferably equal to or longer than the length in the longitudinal direction and the length in the width direction of the power generation unit. Thereby, the current generated by the power generation can be collected efficiently.

  By the way, during the operation of the cell stack device described above, the fuel gas that has not been used for power generation discharged from the fuel gas flow path 36 is burned on the upper end side of the fuel cell 3. In case of sudden fluctuations in load or low output such as at night, misfiring may occur, and the temperature of the fuel cell 3 and the temperature of the reformer 6 will not increase with the misfiring, and power generation will not be possible. Long-term reliability may be reduced.

  Therefore, as shown in FIG. 2, in the cell stack device 12 of the present embodiment, the fuel cells 3 are arranged such that the upper ends of the fuel gas flow paths 36 are at different positions in the height direction. . Specifically, in the cell stack device 12 shown in FIGS. 1 to 3, the upper ends of the plurality of fuel gas flow paths 36 of the respective fuel cells 3 are lowered on the oxygen-containing gas introduction member 11 side. The side opposite to the oxygen-containing gas introduction member 11 is increased.

Thereby, for example, misfire of each fuel gas channel 36 can be suppressed, and the fuel gas channel 36 whose upper end is located above (in other words, the fuel gas channel 36 located on the opposite side of the oxygen-containing gas introduction member 11). .)) Even when misfiring occurs, combustion occurs in the fuel gas passage 36 whose upper end is located below (in other words, the fuel gas passage 36 located on the oxygen-containing gas introduction member 11 side). In addition to part of the combustion heat flowing to the fuel gas flow path 36 located on the side opposite to the oxygen-containing gas introduction member 11, part of the combustion flame is located on the side opposite to the oxygen-containing gas introduction member 11. The fuel gas flow path 36 is fluctuated. As a result, reignition can be performed at the upper end side of the fuel gas flow path 36 located on the opposite side to the oxygen-containing gas introduction member 11. Therefore, long-term reliability can be improved as compared with the cell stack device in which the upper end position of the fuel gas channel 36 is the same position.

  In the fuel cell 3, at least one end side (oxygen-containing gas introduction member 11 side) of the plurality of gas flow paths 36 is lower than the other end side (opposite side of the oxygen-containing gas introduction member 11). However, in order to efficiently re-ignite the misfired fuel gas flow path 36, the upper end positions of the plurality of fuel gas flow paths 36 are sequentially changed from one end side to the other end side. That is, it is preferable that it is inclined from the one end side to the other end side. Thereby, misfire can be suppressed or re-ignited more efficiently.

  Therefore, in the cell stack device 12 shown in FIG. 2, the fuel cell 3 is arranged so as to be perpendicular to the manifold 4 and the upper end side of the fuel cell 3 is cut obliquely. For example, the fuel cell 3 itself may have a shape with a flat upper end, and the fuel cell 3 may be fixed to the manifold 4 so as to be inclined.

  In addition, in the plurality of fuel gas flow paths 36, it is preferable to provide the side where the ambient temperature is high at a low position. By disposing the fuel gas flow path 36 with the lower upper end position on the higher ambient temperature side, it is possible to suppress misfire in the fuel gas flow path 36 with the lower upper end position and to facilitate re-ignition. This makes it possible to easily suppress misfire and re-ignite the entire fuel gas flow path 36.

  Therefore, in the above description, the example in which the upper end of the fuel gas channel 36 located on the oxygen-containing gas introduction member 11 side is set to a low position in the plurality of fuel gas channels 36 has been described. However, for example, in the case of the cell stack device 12 having a configuration in which the ambient temperature on the side opposite to the oxygen-containing gas introduction member 11 is high, the upper end of the fuel gas passage 36 on the side opposite to the oxygen-containing gas introduction member 11 is at a low position. It can also be provided.

  FIG. 4 is an external perspective view showing another example of the cell stack device of the present embodiment. FIG. 4 shows a cell stack device 39 in which 15 cylindrical fuel cells 41 are arranged on a manifold 40. The cylindrical fuel cell 41 has one fuel gas channel 42 penetrating in the longitudinal direction inside, and from this fuel gas channel 42 side, the fuel electrode layer, the solid electrolyte layer, and the oxygen A solid oxide fuel cell 41 in which polar layers are sequentially stacked is shown. Further, in FIG. 4, current collecting members and conductive members that electrically connect the fuel cells 41 are omitted.

  In the cylindrical fuel cell 41 having only one fuel gas flow path 42 in such an interior, similarly to the fuel cell 3 described with reference to FIGS. By burning the fuel gas that has not been used for power generation, the temperature of the fuel cell 41 can be maintained at a high temperature.

By the way, also in the cylindrical fuel cell 41, the problem of misfire occurs similarly to the above, and there exists a possibility that long-term reliability may fall by it. Therefore, even in the case of the cylindrical fuel cell 41, it is preferable that the cell stack device be configured such that re-ignition is easy when the misfire is suppressed or misfired as described above.

  Here, in the cell stack device 12 shown in FIGS. 1 to 3, since each fuel cell 3 has a plurality of fuel gas flow paths 36, misfire is caused in each fuel cell 3. Suppression and reignition can be easily performed. On the other hand, in the cylindrical fuel cell 41 having only one fuel gas passage 42, misfire can be suppressed and reignition can be easily performed with each fuel cell 41 alone. It can be difficult.

  Therefore, in the cell stack device 39 shown in FIG. 4, 15 fuel cells 41 are arranged, and the fuel cells 41 located on the center side of the manifold 40 are located on the end side (in FIG. 4). By changing the length of the fuel cell 41 located on the front side or the back side, the fuel cell 41 is arranged so that the upper end of the fuel gas channel 42 is at a different position in the height direction. Yes. Specifically, in FIG. 4, the length of the fuel cell 41 located on the center side of the manifold 40 is shortened, and the upper end of the fuel gas passage 42 is arranged to be low.

  Thereby, misfire of the fuel gas channel 42 in each fuel cell 41 can be suppressed, and the fuel gas channel 42 whose upper end is located above (in other words, the fuel cell 41 located on the end side in FIG. 4). Even if misfire occurs, if combustion occurs in the fuel gas flow 42 (in other words, the fuel cell 41 located on the center side of the manifold 40) whose upper end is located below, the combustion heat Is likely to flow to the other fuel battery cell 41 side, and in some cases, a part of the combustion flame is also likely to fluctuate to the other fuel battery cell 41, and the upper end of the fuel gas channel 42 located on the end side. Can be re-ignited on the side. Therefore, the long-term reliability can be improved as compared with the cell stack device in which the position of the upper end of the fuel gas passage 42 is the same position.

  Incidentally, in FIG. 4, the length of the fuel cell 41 located on the most central side of the manifold 40 is the shortest, and the length of the fuel cell 41 is gradually increased toward the end side. An example is shown.

  In the above description, the cell stack device 12 in which the fuel cells 3 and 41 are arranged in a matrix is shown, but the present invention is also applicable to, for example, a cell stack device in which fuel cells are arranged in a circle. Can do.

  FIG. 5 is a cross-sectional view showing another example of the module of the present embodiment, and includes an ignition device 43 above the fuel cell 3 as compared with the cross-sectional view of the module 1 shown in FIG.

  The module containing each cell stack device as described above is provided with an ignition device 43 in order to efficiently burn the fuel gas that has not been used for power generation discharged from each fuel gas flow path 36. Is preferred. By operating the ignition device, the fuel gas that has not been used for power generation discharged from each fuel gas flow path 36 can be efficiently burned. In addition, as the ignition device 43, an ignition heater, a burner, etc. can be used suitably, for example.

  By the way, it is difficult to arrange such ignition devices 43 on all the fuel cells 3 and all the fuel gas flow paths 36 from the viewpoint of the structure and cost. Therefore, in order to reduce the number of ignition devices 43 and to suppress misfire in each fuel gas channel 36 or to easily perform reignition, the ignition device 43 has an upper end in the fuel gas channel 36. It is preferable to provide above the fuel gas flow path 36 located at the lowest position.

  As a result, misfire of the fuel gas channel 36 whose upper end is located at the lowest position can be suppressed, and re-ignition can be easily performed. Therefore, misfire of the fuel gas channel 36 located above the fuel gas channel 36 can be efficiently performed. In addition, reignition can be performed more easily. FIG. 5 shows an example in which the ignition device 43 is arranged above the fuel gas flow path 36 whose upper end is located at the lowest position.

  FIG. 6 shows an example of the fuel cell device of the present embodiment in which the fuel cell module 1 shown in FIG. 1 and an auxiliary machine (not shown) for operating the fuel cell module 1 are housed in an outer case. FIG. In FIG. 6, a part of the configuration is omitted.

  The fuel cell device 44 shown in FIG. 6 divides the inside of an outer case made up of support columns 45 and an outer plate 46 by a partition plate 47, and a module storage chamber 48 for storing the above-described fuel cell module 1 on the upper side. The lower side is configured as an auxiliary equipment storage chamber 49 for storing auxiliary equipment for operating the fuel cell module 1. In addition, the auxiliary machine stored in the auxiliary machine storage chamber 49 is omitted.

  Further, the partition plate 47 is provided with an air circulation port 50 for flowing the air in the auxiliary machine storage chamber 49 to the module storage chamber 48 side, and a part of the exterior plate 46 constituting the module storage chamber 48 is An exhaust port 51 for exhausting the air in the module storage chamber 48 is provided.

  In such a fuel cell device 44, as described above, the fuel cell module 1 with improved power generation efficiency is stored in the module storage chamber 48, and an auxiliary machine for operating the fuel cell module 1 is connected to the auxiliary device storage chamber 49. By being housed in the fuel cell device, the fuel cell device 44 with improved power generation efficiency can be obtained.

  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 5 constituting the cell stack device 12, when a temperature distribution is generated in which the temperature on the center side in the arrangement direction of the fuel cells 3 is high and the temperature on the end side is low, the ignition device 43 is Alternatively, the fuel cell 3 may be disposed only above the fuel cell 3 located at the center of the arrangement direction of the fuel cells 3 and above the fuel gas flow path 36 whose upper end is located at the lowest position.

  Also, for example, in the cell stack device 12 shown in FIGS. 1 to 3, as in the cell stack device 39 shown in FIG. 4, the fuel cell 3 (that is, the fuel cell) located on the center side of the manifold 4. Each fuel cell 3 can be arranged so that the fuel gas flow path 36 in the fuel cell 3) located at the center in the arrangement direction 3 is at the lowest position. Thereby, about each fuel cell 3 which comprises the cell stack apparatus 12, misfire can be suppressed efficiently and reignition can be performed easily.

  In the above-described example, the fuel cell 3 called a so-called vertical stripe type has been described, but a horizontal stripe type fuel cell in which a plurality of power generation element portions generally called a horizontal stripe type are provided on a support may be used. it can.

1: Fuel cell module 2: Storage container 3, 41: Fuel cell 4, 40: Manifold 5: Cell stack 12, 39: Cell stack device 36, 42: Fuel gas flow path 43: Ignition device 44: Fuel cell device

Claims (7)

  A plurality of fuel cells each configured to generate power with a fuel gas and an oxygen-containing gas and to have a gas flow path penetrating the inside in the longitudinal direction and to burn the fuel gas not used for power generation on the upper end side And a manifold that communicates with the gas flow path and supplies fuel gas to the gas flow path, and the fuel cells are arranged such that the upper ends of the gas flow paths are at different positions in the height direction. A cell stack device characterized in that:   The fuel cell has a cylindrical shape having a plurality of gas passages penetrating the inside in the longitudinal direction, and each of the fuel cells has a position where the upper ends of the gas passages in the fuel cells differ from each other. The cell stack device according to claim 1, wherein the cell stack device is provided as follows.   The cell stack device according to claim 2, wherein upper ends of a plurality of gas flow paths in each of the fuel cells are inclined from one end side to the other end side.   The fuel cell has a cylindrical shape having one gas flow path penetrating the inside in the longitudinal direction, and the plurality of fuel cells are arranged so that their upper ends are different from each other. The cell stack device according to claim 1.   The cell stack device according to any one of claims 1 to 4 is stored in a storage container, and the fuel cell in the cell stack device is positioned at the lowest position in the gas flow path. The fuel cell module is arranged so that the gas flow path is positioned on a high temperature side.   6. The fuel cell module according to claim 5, further comprising an ignition device above the gas flow channel having an upper end located at the lowest position in the gas flow channel. A fuel cell device comprising the fuel cell module according to claim 5 or 6 accommodated in an outer case.