JP6185328B2 - Fuel cell device - Google Patents

Description

  The present invention relates to a fuel cell device.

  Several types of power generation systems for fuel cells are known, but in recent years, solid oxide fuel cells (SOFC) capable of achieving high power generation efficiency have attracted attention.

  A main component of a solid oxide fuel cell system (hereinafter referred to as an SOFC system as appropriate) is a fuel cell device. A fuel cell device mainly includes a cell stack (fuel cell stack) that is an assembly of a plurality of fuel cell cells that generate power by an electrochemical reaction between a hydrogen-rich gas (including pure hydrogen) and an oxidant (generally air). An off-gas combustion section for burning a hydrogen-rich gas and an oxidant (hereinafter referred to as off-gas) that has not been used for power generation in the cell stack to maintain the cell stack at a high temperature, and a vessel surrounding the cell stack and the off-gas combustion section. Consists of including.

  Some containers include an outer shell, an inner shell enclosed in the outer shell, and a partition wall containing the inner shell. The outer shell has at least a side wall facing the side surface portion of the cell stack, and has at least an inner shell with an open top that encloses the cell stack and the off-gas combustion unit, and a side wall disposed outside the side wall of the inner shell. A partition wall that forms an exhaust gas flow path between the shell and the side wall of the shell is included inside. The exhaust gas flow channel distributes exhaust gas from off-gas combustion from top to bottom. In addition, an oxidant flow path is formed between the outer shell and the partition wall. The oxidant channel allows the oxidant to flow from the bottom to the top. The fuel cell apparatus provided with such a container is disclosed by patent documents 1-4.

  In addition, the fuel cell device includes components (hereinafter referred to as insertion components) such as sensors for performing stable power generation, an ignition device for igniting the off-gas combustion unit, and an electrode for taking out the generated electric power. Patent Documents 2 to 4 disclose an insertion part disposed across the exhaust gas flow path and the oxidant flow path.

JP 2010-49969 A JP 2010-44992 A JP2011-29201A JP 2007-59377 A

  As described above, when the insertion part is arranged across the exhaust gas flow path and the oxidant flow path, the fuel cell apparatus is inserted due to the heat generated by the cell stack and / or the combustion heat of the off-gas combustion section. A part of the component is heated to a high temperature. For this reason, deterioration such as breakage due to the high temperature of the inserted part may occur. Although it is conceivable to use an insert member having high heat resistance for this problem, this leads to an increase in the manufacturing cost of the insert part and consequently the fuel cell device.

  Therefore, an object of the present invention is to provide a fuel cell device that can suppress the above-described problem and suppress deterioration of an insertion part at a high temperature.

According to a first aspect of the present invention, there is provided a fuel cell device comprising a cell stack and a container that accommodates the cell stack therein,
The container has an outer shell, an inner shell arranged inside the outer shell, and an exhaust gas partition wall arranged inside the inner shell,
Between the inner shell and the exhaust gas partition wall, an exhaust gas passage for deriving the exhaust gas generated from the cell stack in the container to the outside of the container is defined,
Further comprising an insertion part that penetrates the outer shell, the inner shell, and the exhaust gas partition wall to reach the inside of the container,
The inner shell and the exhaust gas partition are in contact with each other so as to surround the penetrating part in the penetrating part of the container through which the insertion part passes through the outer shell, the inner shell, and the exhaust gas partitioning wall. A fuel cell device is provided.

  In the fuel cell device of the present invention, by eliminating the direct contact between the high temperature exhaust gas and the insertion part, the amount of heat transfer from the high temperature exhaust gas to the insertion part is reduced, and the heating of the insertion part is suppressed. ing.

  In the fuel cell device of the present invention, the outer shell may be configured to be flat in the penetrating portion. With such a configuration, it is not necessary to process the outer shell, and when a heat insulating material is disposed on the outer surface of the container or when the fuel cell device is unitized, the manufacturing cost is reduced and the manufacturing workability is improved. To do.

  In the fuel cell device of the present invention, an oxidant flow path for allowing an oxidant to be supplied to the cell stack to flow is defined between the outer shell and the inner shell. The outer shell may protrude toward the inner shell so that the outer shell and the inner shell are not in contact with each other in the penetrating portion. The protruding amount of the outer shell toward the inner shell may be larger than the protruding amount of the inner shell. By setting it as such a structure, an insertion part can be efficiently cooled with an oxidizing agent.

  In the fuel cell device according to the present invention, an oxidant flow path for flowing an oxidant supplied to the cell stack is defined between the outer shell and the inner shell, and the penetrating portion of the oxidant flow path With respect to the downstream side, the outer shell is configured to protrude in a direction away from the inner shell, or the inner shell is configured to protrude toward the exhaust gas partition wall. There may be. With such a configuration, the insertion part can be efficiently cooled by the oxidizing agent.

  In the fuel cell device of the present invention, the insertion part may be at least one of a temperature measurement unit, an ignition device, and a current extraction unit.

  According to the fuel cell device of the present invention, it is possible to suppress thermal deterioration of the insertion part due to exposure to the exhaust gas flowing through the exhaust gas passage. Therefore, it is possible to extend the life of the inserted parts and thus the fuel cell device, and to reduce their manufacturing costs.

1A is a schematic cross-sectional view of a fuel cell device to which the present invention is applied, and FIG. 1B is a schematic cross-sectional view taken along line XX of FIG. 1A. 2A and 2B are cross-sectional views in the vicinity of the penetrating portion of the container according to the first embodiment of the present invention. 3A and 3B are cross-sectional views in the vicinity of the penetrating portion of the container according to the modification of the first embodiment of the present invention. FIG. 4 is a cross-sectional view of the vicinity of the penetrating portion of the container according to another modification of the first embodiment of the present invention. FIG. 5 is a block diagram showing an outline of the fuel cell device.

<First Embodiment>
1A, 1B, and 5 are conceptual diagrams of a generally known fuel cell device 900. FIG. A generally known fuel cell device 900 is a solid oxide fuel cell (SOFC), and includes a container 9, a reforming unit 16 disposed in the container 9, a plurality of fuel cells 10, and an off-gas combustion area 14. . In FIG. 1A, the front side and the back side are the fuel cell device 900 and the front side and rear side of the container 9, respectively. In FIG. 1A, the left and right sides are the left and right sides of the fuel cell device 900 and the container 9, and the upper and lower sides in FIG. 1A are the upper and lower sides of the fuel cell device 900 and the container 9, respectively. To do.

As shown in FIG. 5, the fuel cell 10 includes a fuel electrode 11, an electrolyte 12, and an oxidant electrode 13. The electrolyte 12 conducts oxide ions at high temperatures. The fuel electrode 11 generates electrons and water by reacting oxide ions with hydrogen in the fuel. The electrode reaction of the following formula (1) occurs at the oxidant electrode 13 and the electrode reaction of the following (2) occurs at the fuel electrode 11 to generate power.
Oxidant electrode: 1 / 2O ₂ + 2e ⁻ → O ²⁻ (electrolyte) (1)
Fuel electrode: O ²⁻ (electrolyte) + H ₂ → H ₂ O + 2e (2)
The fuel cell device 900 includes a large number of fuel cells 10 as described above, and these are electrically connected in series (and in parallel) to form a cell stack (fuel cell stack) that is an assembly of the fuel cells 10. ) 6. As the fuel cell 10, a known one such as a cylindrical shape or a flat plate shape can be selected. In addition, since the arrangement of the fuel cells 10 can be arbitrarily selected, the cell stack 6 in FIG. 1 is schematically shown by omitting them. The supply form of the hydrogen rich gas and the oxidizing agent is designed according to the shape of the cell stack 6. Therefore, it goes without saying that the arrangement and number of the hydrogen-rich gas supply member 42 and the oxidant supply member 52 are not limited to the forms shown in FIGS.

  The reforming unit 16 reforms the hydrogen-containing fuel by a reforming reaction using a reforming catalyst to generate a hydrogen rich gas. As the hydrogen-containing fuel, for example, a hydrocarbon fuel is used. As the hydrocarbon fuel, a compound containing carbon and hydrogen in a molecule (which may contain other elements such as an enzyme) or a mixture thereof is used. Examples of hydrocarbon fuels include hydrocarbons, alcohols, ethers, and biofuels. These hydrocarbon fuels are derived from conventional fossil fuels such as petroleum and coal, and synthetic systems such as synthesis gas. Those derived from fuel and those derived from biomass can be used as appropriate. Specific examples of hydrocarbons include methane, ethane, propane, butane, natural gas, LPG (liquefied petroleum gas), city gas, town gas, gasoline, naphtha, kerosene, and light oil. Examples of alcohols include methanol and ethanol. Examples of ethers include dimethyl ether. Examples of biofuels include biogas, bioethanol, biodiesel, and biojet. When the hydrogen-containing fuel contains sulfur, it is preferable to supply the reforming unit 16 after removing sulfur by, for example, a desulfurization unit (not shown). The reforming method in the reforming unit 16 is not particularly limited, and for example, steam reforming, partial oxidation reforming, autothermal reforming, and other known reforming methods can be performed alone or in combination. FIG. 5 illustrates a steam reforming method.

  The hydrogen-rich gas generated in the reforming unit 16 is supplied to the fuel electrode 11 side of the fuel cell 10 constituting the cell stack 6. On the other hand, an oxidant such as air is supplied to the oxidant electrode 13 side of the fuel cell 10. An electrolyte 12 is disposed between the fuel electrode 11 and the oxidant electrode 13. The fuel cell 10 generates power by an electrochemical reaction between the supplied hydrogen-rich gas and the oxidant.

  Gas that has not been used for power generation at the fuel electrode 11 and the oxidant electrode 13 is burned in the off-gas combustion area 14. The combustion heat at this time is used for heating the oxidant before being supplied to the reforming unit 16, the fuel cell 10, and the oxidant electrode 13.

  The container 9 includes an outer shell 2, an inner shell 3 included in the outer shell 2, and an exhaust gas partition wall 4 included in the inner shell 3. The outer shell 2 has a hexahedral box shape and includes a pair of left and right left and right side walls 2a, 2b, a top plate 2c, and a bottom plate 2d in a front view. The inner shell 3 has a pair of left and right left side walls 3a and 3b, a top plate 3c, and a bottom plate 3d in front view. The exhaust gas partition wall 4 has a pair of left and right left side walls 4a, 4b, and a bottom plate 4d in a front view, and is formed in a channel shape with an open top or a U groove shape with an open top. In the exhaust gas partition wall 4, a cell stack 6, an off-gas combustion area 14, a reforming unit 16, and an oxidant supply channel 52, which are aggregates of a plurality of fuel cells 10, are disposed.

  The outer shell 2 and the inner shell 3 form an oxidant channel 51 through which the oxidant flows. An exhaust gas flow path 61 is formed by the inner shell 3 and the exhaust gas partition wall 4. The oxidant taken in from the oxidant inlet 50 opened in the bottom plate 2d of the outer shell 2 flows from the lower side to the upper side through the oxidant channel 51, and is supplied with the oxidant connected to the upper wall 3c of the inner shell 3. It is supplied to the oxidant electrode 13 of the cell stack 6 through the member 52. On the other hand, the hydrogen-rich gas generated in the reforming unit 16 is supplied to the fuel electrode 11 of the cell stack 6 through the hydrogen-rich gas supply channel 42. Excess hydrogen-rich gas and oxidant that have not been used for power generation in the cell stack 6 are combusted in the off-gas combustion area 14, and then flow through the exhaust gas flow channel 61 downward from above to open to the bottom plate 3 d of the inner shell 3. The exhaust gas outlet 60 is led out of the fuel cell device 900. During operation of the fuel cell device 900 during normal power generation, an oxidant of about 120 to 450 ° C. continuously flows through the oxidant channel 51, and an exhaust gas of about 250 to 480 ° C. continues through the exhaust gas channel 61. In circulation. In FIG. 1 to FIG. 3, a symbol surrounded by a circle around the outer periphery of the black circle indicates a gas flow from the back of the paper to the front, and a symbol surrounded by a circle indicates the back from the front of the paper. The flow of gas is shown.

  In addition, the fuel cell device 900 includes an insertion member disposed through the left side wall 2 a of the outer shell 2, the left side wall 3 a of the inner shell 3, and the left side wall 4 a of the exhaust gas partition wall 4. The insertion member includes, for example, an ignition device for igniting the off-gas combustion area 14, a thermometer for measuring the temperature of the cell stack and the flame temperature of the off-gas combustion area 14, and a current extraction unit for taking out the generated electric power. Parts. In FIG. 1, the temperature measurement part 7 which measures the flame temperature of the off-gas combustion area 14 is illustrated.

  Next, in the container 1 of the fuel cell device 100 of the present embodiment, the portion of the container 1 where the temperature measuring unit 7 penetrates the container 1, that is, the flow path structure of the container 1 in the penetrating part is shown in FIG. , (B) will be described. 1 to 4, a region including a portion (penetrating portion) in which the temperature measuring unit 7 penetrates the outer shell 2, the inner shell 3, and the exhaust gas partition wall 4 is illustrated as a region P. The container 1 is the same as the container 9 except for the structure of the region including the penetrating portion. About the container 1, about the same structure and element as the container 9, the same code | symbol as what was used with the container 9 is attached | subjected, and description is abbreviate | omitted. FIG. 2A is a partial cross-sectional view of the left side of the container 1 as viewed from the front side when the container 1 is cut along a plane perpendicular to the front-rear direction at the penetrating portion. FIG. 2B is a partial cross-sectional view of the left side when the container 1 is cut along a plane perpendicular to the vertical direction at the penetrating portion and viewed from above. The cell stack 6 is disposed on the right side of the temperature measuring unit 7 in FIGS. 2 (A) and 2 (B).

  In the present embodiment, the left side wall 3a of the inner shell 3 protrudes as a frustoconical protrusion 31 toward the left side wall 4a of the exhaust gas partition 4 so as to surround the through part (insertion member) around the through part. The top surface 32 of the projecting portion 31 is in contact with and in close contact with the left side wall 4a of the exhaust gas partition wall 4. That is, the exhaust gas flow path 61 is blocked by the left side wall 3 a of the inner shell 3 in the through portion and the periphery thereof, and the exhaust gas flow is between the left side wall 3 a of the inner shell 3 and the left side wall 4 a of the exhaust gas partition wall 4. The passage 61 is not defined (the width of the exhaust gas passage 61 is zero).

  By closing the exhaust gas passage 61 with the left side wall 3a of the inner shell 3 having such a shape in the penetrating portion, the high-temperature exhaust gas does not pass through the penetrating portion and circulates around there, so that the exhaust gas flows. Direct contact with the temperature measuring unit 7 is prevented. Therefore, it is suppressed that the temperature measurement part 7 is heated by contact with high temperature exhaust gas.

  The dimension of the top surface 32 in the front-rear direction and the vertical dimension, that is, the region where the exhaust gas flow channel 61 is not defined (the region where the exhaust gas flow channel 61 is closed, the width of the exhaust gas flow channel 61 becomes zero. The dimensions in the front-rear direction and the vertical direction of the area) are arbitrary. The protruding portion 31 is not limited to the truncated cone shape, and may be any shape such as a columnar shape, each columnar shape, a truncated pyramid shape, or a triangular truncated cone shape. The shape of the top surface 32 is not limited to a circle, but a rectangle, a triangle, Any shape such as a trapezoid may be used. 2 (A) and 2 (B), the protruding portion 31 of the left side wall 3a of the inner shell 3 is drawn so as to be bent at an obtuse angle, but it is an aspect that is bent and protruded in a curved shape. May be.

  In the present embodiment, the left side wall 2a of the outer shell 2 projects as a frustoconical projecting portion 21 toward the left side wall 3a of the inner shell 3 around the penetrating portion, and the top surface of the projecting portion 21 22 has a top surface 32 of the protruding portion 31 of the left side wall 3a of the inner shell 3 and a width wo2 and extends substantially in parallel. Here, the protruding amount of the protruding portion 21 is larger than the protruding amount of the protruding portion 31. Therefore, the width wo2 is between the left side wall 2a of the outer shell 2 and the left side wall 3a of the inner shell 3 in a portion (hereinafter referred to as a non-penetrating portion) different from the through portion where the temperature measuring unit 7 is disposed. It is smaller than the width wo1. That is, the width of the oxidant channel 51 in the left-right direction is smaller in the penetrating portion than in the non-penetrating portion. (Wo2 <wo1).

  The left side wall 2a of the outer shell 2 is formed in such a shape around the penetrating part, and the width wo2 of the oxidant channel 51 in the penetrating part is set as the width wo2 in the horizontal direction of the oxidant channel 51 in the non-penetrating part. By making it smaller than wo1, it is possible to increase the flow rate of the oxidant flowing around the temperature measuring unit 7 disposed in the penetrating part. In general, a boundary film having a predetermined thickness is formed at the boundary between the gas and the solid. This boundary film becomes thinner as the gas flow rate increases, and becomes thicker as it decreases. Furthermore, as the film becomes thinner, the amount of heat transfer between the gas and the solid increases, and as the film becomes thicker, the amount of heat transfer between the gas and the solid decreases. Here, during the normal power generation operation of the fuel cell device, the outer surface of the temperature measuring unit 7 can reach about 350 to 450 ° C., whereas the oxidant is as low as about 200 to 250 ° C. Therefore, the oxidizing agent can act as a cooling medium for the temperature measuring unit 7. Therefore, the temperature measuring unit 7 can be efficiently cooled by the oxidizing agent.

  The longitudinal and vertical dimensions of the top surface 22 of the protruding portion 21 of the left side wall 2a of the outer shell 2 can be arbitrarily set, and the longitudinal direction of the top surface 32 of the protruding portion 31 of the left side wall 3a of the inner shell 3 can be set. It is preferable to set within a range smaller than the dimension and the dimension in the vertical direction. The projecting portion 21 is not limited to a truncated cone shape, and may be an arbitrary shape such as a columnar shape, a polygonal column shape, a truncated pyramid shape, or a triangular truncated cone shape. The shape of the top surface 21 is not limited to a circle, and is rectangular, triangular, trapezoidal. Or any other shape. 2 (A) and 2 (B), the protruding portion 21 of the left side wall 2a of the outer shell 2 is drawn so as to be bent at an obtuse angle, but it is an aspect that protrudes in a curved shape. May be.

  The structure of the penetration part demonstrated above can be produced as follows. First, before the container 1 is assembled, the protruding portion 21 and the protruding portion 31 are formed on the left side wall 2a of the outer shell 2 and the left side wall 3a of the inner shell 3 by pressing. Next, the top surface 22, the top surface 32, and the left side wall 4a of the exhaust gas partition wall 4 are formed with openings for allowing the temperature measuring unit 7 to penetrate therethrough. When the container 1 is assembled, the top surface 32 of the protrusion 31 formed on the left side wall 3a of the inner shell 3 is brought into close contact with the left side wall 4a of the exhaust gas partition wall 4 by spot welding or the like. Then, after assembling the container 1, the temperature measuring unit 7 is inserted into the opening. At this time, the gaps between the left side wall 2a of the outer shell 2 and the left side wall 3a of the inner shell 3 and the temperature measuring unit 7 are sealed with a sealing material (not shown) or the like. Thereby, the gas in the container 1 is prevented from leaking outside the container 1, and the exhaust gas flows into the oxidant flow path 51 or the oxidant flows into the exhaust gas flow path 61.

  As described above, with respect to the structure around the penetration portion in the present embodiment, the temperature measurement unit 7 is penetrated through the left side wall 2a of the outer shell 2 of the container 1, the left side wall 3a of the inner shell 3, and the left side wall 4a of the exhaust gas partition wall 4. Although the case where it arrange | positions was demonstrated as an example, the case where the temperature measurement part 7 is arrange | positioned through the right side wall 2b of the outer shell 2 of the container 1, the right side wall 3b of the inner shell 3, and the right side wall 4b of the exhaust gas partition 4 Is the same. The container 1 also has an outer shell 2, an inner shell 3, and an exhaust gas partition wall 4 on the side surface in the front-rear direction, and an oxidant channel 51, an inner shell 3 and an exhaust gas partition wall 4 between the outer shell 2 and the inner shell 3. In the case where the temperature measuring unit 7 is disposed through the side surface in the front-rear direction in the structure including the exhaust gas flow channel 61 between them, the structure around the through part in the present embodiment can be similarly adopted. Further, it is optional to provide the penetrating portion at any position on the outer surface of the container 1 (the surface of the outer shell 2). Although the structure around the penetration portion has been described by taking the temperature measuring unit 7 that measures the flame temperature of the off-gas combustion area 14 as an example of the insert part, the insert part is an ignition device (for example, an ignition heater, It can be replaced with various insertion parts necessary for the operation of the fuel cell device 100, such as a spark plug), a temperature measuring unit of the cell stack 6, and a current extracting unit. At this time, the protrusions 21 and 31 may be formed at positions suitable for the use of various insertion parts.

  The effects of the present invention according to the present embodiment are summarized as follows.

  According to the fuel cell device 100 of the present embodiment, by eliminating direct contact between the high-temperature exhaust gas and the insertion part, the amount of heat transferred from the exhaust gas to the insertion part is reduced, and thermal deterioration of the insertion part is suppressed. Has been. Therefore, it is possible to extend the lifetime of the insertion parts such as the temperature measurement unit 7, the ignition device, and the current extraction unit, and it is possible to manufacture them without using a material having high heat resistance. This point is also advantageous in terms of manufacturing cost.

  In addition, the fuel cell device 100 of the present embodiment has a structure in which the flow rate of the oxidant is increased around the insertion part arranged in the through portion. Thus, the insert is effectively cooled by the oxidant. Since the insertion part is effectively cooled by the oxidant, it is possible to extend the life of the insertion part such as the temperature measurement unit 7, the ignition device, the current extraction unit, and the like. It can be produced without using it. This point is also advantageous in terms of manufacturing cost.

  Moreover, according to the fuel cell device 100 of the present embodiment, as described above, the direct contact between the high-temperature exhaust gas and the insertion part is eliminated, and heating by heat conduction from the exhaust gas is suppressed. Furthermore, since the insertion part is efficiently cooled by the oxidant and heat transfer inside the insertion part is also suppressed, the amount of heat released from the inside of the container 1 to the outside through the insertion part can be reduced. .

  Further, in the fuel cell device 100 of the present embodiment, as described above, heating by heat conduction from the exhaust gas to the insertion part is suppressed, and cooling of the insertion part by the oxidant is effectively performed. For this reason, it is possible to prevent the temperature of the electrical connection portion of the insertion part such as the temperature measurement unit 7, the ignition device, and the current extraction unit from being increased.

  In addition, the fuel cell device 100 of the present embodiment has the above-described effect only by performing simple processing such as press processing, laser processing, and welding processing on the outer shell 2, the inner shell 3, and the exhaust gas partition 4 constituting the container 1. This is advantageous in terms of manufacturing cost.

Next, a modification of the fuel cell device 100 of the present embodiment will be described. In the following description of the modified examples, the description of the same configuration as the above embodiment is omitted.
[Modification 1]
3A and 3B are cross-sectional views of the fuel cell device 100 according to the first modification. FIG. 3A is a partial cross-sectional view of the left side of the container 1 as viewed from the front side when the container 1 is cut along a plane perpendicular to the front-rear direction at the penetrating portion. FIG. 3B is a partial cross-sectional view of the left side when the container 1 is cut along a plane perpendicular to the vertical direction at the penetrating portion and viewed from above. In the fuel cell device 100 of the present modification, unlike the fuel cell device 100 of the above-described embodiment, the protruding portion 21 that protrudes the left side wall 2a of the outer shell 2 of the container 1 toward the left side wall 3a of the inner wall 3 is provided. Except not having provided, it has the structure of the penetration part similar to the said embodiment.

  In the present modification, the exhaust gas flow path 61 is sealed around the penetrating portion, so that contact with the exhaust gas of the temperature measuring unit 7 is prevented. At the same time, since the protruding portion 21 is not provided on the left side wall 2a of the outer shell 2 constituting the container 1, the container 1 maintains the conventional appearance. The fact that the left side wall 2a of the outer shell 2 which is the outer surface of the container 1 is less uneven means that the outer shell 2 does not need to be processed, and that a heat insulating material is disposed on the outer surface of the container 1, or fuel It is further advantageous in that the unitization of the battery device 100 contributes to manufacturing cost and manufacturing workability.

[Modification 2]
FIG. 4 is a partial cross-sectional view of the left side of the container 1 of the fuel cell device 100 according to Modification 2 cut along a plane perpendicular to the front-rear direction at the penetrating portion and viewed from the front side. In the present modification, unlike the above embodiment, the left side wall 2a of the outer shell 2 faces the outside of the container 1 (in a direction away from the inner shell 3) on the downstream side of the penetrating portion of the oxidant channel 51. The width wo4 between the left side wall 2a of the outer shell 2 and the left side wall 3a of the inner shell 3 is larger than the width wo3 in the left-right direction of the oxidant channel 51 in the penetrating portion. In addition, the left side wall 3a of the inner shell 3 protrudes toward the left side wall 4a of the exhaust gas partition wall 4 on the downstream side from the penetrating portion of the oxidant channel 51, whereby the left side wall 2a of the outer shell 2 and the inner shell 3 The width wo4 between the left side wall 3a and the width wo3 in the left-right direction of the oxidant channel 51 in the penetrating portion may be made larger.

  Thus, by making the width wo4 in the left-right direction of the oxidant flow path 51 in the portion located downstream from the penetration part of the insertion part larger than the width wo3 in the left-right direction of the oxidant flow path 51 in the penetration part. The pressure of the oxidant can be drastically reduced downstream from the penetrating part of the oxidant channel 51, and the flow rate of the oxidant in the penetrating part can be increased by the pressure difference between the upstream side and the downstream side of the penetrating part. . Also in this modified example, similarly to the above-described embodiment, it is possible to prevent the inserted part from being heated to a high temperature due to heat conduction from the exhaust gas, and to efficiently cool the inserted part using the oxidizing agent.

  In the present embodiment, the projecting portion 31 is formed on the inner shell 3 toward the exhaust gas partition wall 4 so as to close the exhaust gas flow path 61. On the contrary, the exhaust gas partition wall 4 is directed toward the inner shell 3 side. The exhaust gas flow path 61 can also be closed by forming a protrusion and a protrusion top surface in contact with the inner shell 3. Further, a protrusion and a protrusion top surface are formed on the inner shell 3 toward the exhaust gas partition wall 4 side, and a protrusion and a protrusion top surface are formed on the exhaust gas partition wall 4 toward the inner shell 3 side. The exhaust gas flow channel 61 may be closed by bringing the top surface into contact.

  In the present embodiment, the top surface 22 of the protruding portion 21 of the left side wall 2a of the outer shell 2 may be brought into contact with the protruding portion of the inner shell 3 so that the oxidant channel 51 is also closed. Further, the outer shell 2 may be processed so that the width in the left-right direction of the oxidant channel 51 is the same as that of the non-penetrating portion in the penetrating portion. Further, the fuel cell device 100 may have the characteristics of the first modification and the second modification.

  As mentioned above, although the fuel cell device of the present invention has been described in the embodiment, the present invention is not limited to these specific examples and can be modified within the scope of the present invention.

  For example, in the above-described embodiment, the structure around the penetration portion of the temperature measuring unit 7 has been described as an example of the insertion part. However, as the insertion part, an ignition device (for example, an ignition heater, an ignition plug), a cell in an off-gas combustion area It can be replaced with a temperature measuring unit and a current extracting unit of the stack. At this time, the protrusions 21 and 31 may be formed at positions suitable for installation of the above-described insertion parts.

  Further, in the above embodiment, the container 1 has the outer shell 2, the inner shell 3, and the exhaust gas partition wall 4 on the side surface in the left-right direction, and the oxidant flow path 51, the inner shell 3 is disposed between the outer shell 2 and the inner shell 3. The structure having the exhaust gas flow path 61 between the shell 3 and the exhaust gas partition wall 4 has been described as an example. However, the outer shell 2, the inner shell 3, and the exhaust gas partition wall 4 are also provided on the wall surface in the front-rear direction or the vertical wall surface. A temperature measuring unit 7 that penetrates the side surface in the front-rear direction in a structure including an oxidant channel 51 between the outer shell 2 and the inner shell 3 and an exhaust gas channel 61 between the inner shell 3 and the exhaust gas partition wall 4. In the case of arrangement, the structure around the through portion in the present embodiment can be similarly adopted.

  Further, the exhaust gas in the present invention is not limited to the combustion exhaust gas in the off-gas combustion area 14. In the case of a fuel cell device that employs a device configuration that heats the reforming unit 16 or the cell stack 6 at startup with a heater or the like, the off-gas combustion area 14 may not be provided inside the container 1. Even in such a configuration, it is possible to obtain an effect of suppressing thermal deterioration of the insertion part due to exposure to off-gas heated by the heat generated by the cell stack 6 operating at a high temperature. For this reason, in the above embodiment, the off gas combustion area 14 is exemplified as the off gas combustion area 14 at the upper end of the cell stack 6, but the arrangement of the off gas combustion area 14 is not limited to this. It is also possible to provide a combustion burner inside the inner shell 3, collect off-gas by piping or the like, and connect the off-gas piping to the combustion burner to form the off-gas combustion area 14. Furthermore, although the form which arrange | positions the off-gas combustion area 14 above the cell stack 6 was illustrated, it is not restricted to this. For example, the reforming unit 16 may be disposed between the bottom plate 3 d of the inner shell 3 and the bottom plate 4 d of the exhaust gas partition wall 4.

  Moreover, in the said embodiment, although the reforming part 16 illustrated the form arrange | positioned above the cell stack 6 and the off-gas combustion area 14, it does not restrict to this. For example, the reforming unit 16 may be disposed between the bottom plate 3 d of the inner shell 3 and the bottom plate 4 d of the exhaust gas partition wall 4. Alternatively, a fuel cell device adopting a configuration in which the reforming unit 16 is heated by a heater, or a case where the reforming catalyst filled in the reforming unit 16 is an exothermic reaction and does not have to use off-gas combustion heat. Alternatively, the reforming unit 16 may be disposed outside the container 1 at a position that does not consider the heat received from the off-gas combustion area 14, for example. Furthermore, when using an organic hydride as the hydrogen-containing fuel, the reforming unit 16 may be replaced with a dehydrogenation reactor. When pure hydrogen is used as the hydrogen rich gas, the reforming unit 16 itself may be omitted.

  According to the fuel cell device of the present invention, heating and deterioration of the insertion part can be suppressed, and the life of the insertion part can be extended. Further, the insertion part can be formed of a material that does not have high heat resistance (for example, made of PTFE). Therefore, it is possible to reduce the manufacturing cost of the insertion part and the fuel cell device.

DESCRIPTION OF SYMBOLS 1 Container 2 Outer shell 3 Inner shell 4 Exhaust gas partition 6 Cell stack 7 Temperature measurement part 14 Off-gas combustion area 16 Reforming part 21 Protrusion part 22 Top surface 31 Projection part 32 Top surface 51 Oxidant channel 61 Exhaust gas channel

Claims (8)

A fuel cell device comprising a cell stack and a container for accommodating the cell stack therein,
The container has an outer shell, an inner shell arranged inside the outer shell, and an exhaust gas partition wall arranged inside the inner shell,
Between the inner shell and the exhaust gas partition wall, an exhaust gas passage for deriving the exhaust gas generated from the cell stack in the container to the outside of the container is defined,
Further comprising an insertion part that penetrates the outer shell, the inner shell, and the exhaust gas partition wall to reach the inside of the container,
The inner shell and the exhaust gas partition are in contact with each other so as to surround the penetrating part in the penetrating part of the container through which the insertion part passes through the outer shell, the inner shell, and the exhaust gas partitioning wall. A fuel cell device.   2. The fuel cell device according to claim 1, wherein the inner shell protrudes toward the exhaust gas partition wall and contacts the exhaust gas partition wall.   3. The fuel cell device according to claim 1, wherein the exhaust gas partition wall is configured to protrude toward the inner shell and come into contact with the inner shell.   The fuel cell device according to any one of claims 1 to 3, wherein the outer shell is configured to be flat in the penetrating portion. Between the outer shell and the inner shell, an oxidant flow path for flowing an oxidant supplied to the cell stack is defined,
The insertion part is further disposed through the oxidant flow path in the penetration portion,
The said penetration part is comprised so that the said outer shell may protrude toward the said inner shell so that the said outer shell and the said inner shell may not contact. The fuel cell device described in 1. An oxidant flow path is formed between the outer shell and the inner shell to flow an oxidant supplied to the cell stack,
The insertion part is further disposed through the oxidant flow path in the penetration portion,
In the penetrating portion, the outer shell is configured to protrude toward the inner shell so that the outer shell and the inner shell do not come into contact with each other. The fuel cell device according to claim 2, wherein the fuel cell device is configured to be larger than the size of the protrusion. An oxidant flow path is formed between the outer shell and the inner shell to flow an oxidant supplied to the cell stack,
The outer shell is configured to protrude in a direction away from the inner shell on the downstream side of the penetrating portion of the oxidant flow path, or so that the inner shell protrudes toward the exhaust gas partition wall. The width wo4 in the left-right direction of the oxidant flow path in the portion located downstream of the through portion is configured to be larger than the width wo3 in the left-right direction of the oxidant flow path in the through portion. The fuel cell device according to any one of claims 1 to 6. The fuel cell device according to claim 1, wherein the insertion part is at least one of a temperature measurement unit, an ignition device, and a current extraction unit.

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