JP2011216282A - Fuel battery cell aggregate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel battery with high reliability which can surely intercept inside and outside gas of a gas manifold.SOLUTION: The fuel battery cell aggregate includes: a plurality of fuel battery cells 84 electrically connected and working with fuel gas and oxidizer gas flowing from one end side to the other end side; and a gas manifold 66 to have the plurality of battery cells erected for supplying fuel gas to the fuel battery cells. A support part 68 of the gas manifold at a part with the plurality of fuel battery cells erected is made of an insulating material and provided with a sealing part 302 for sealing the insulating support part and a metallic arrangement part 160 with the insulating support part arranged. The sealing part is of a crystallized glass sealing material, and the fuel battery cell aggregate includes a pressing part for pressing the crystallized glass sealing material.

Description

  The present invention relates to a fuel cell including a plurality of fuel cells operated by a reaction gas (power generation gas).

  Conventionally, as a type of fuel cell, there is a solid oxide fuel cell (hereinafter also referred to as “SOFC”) provided with a plurality of fuel cells operated by a reaction gas. This SOFC usually includes a plurality of fuel cells arranged in a power generation chamber, supplies air as an oxidant gas supplied into the power generation chamber to the cathode electrode of the fuel cell, and the fuel cell. The anode electrode is configured so that a power generation reaction can be caused by supplying hydrogen gas as a fuel gas supplied through a gas manifold.

As such an SOFC, for example, in a fuel cell assembly that includes a cell in which a gas passage is formed and one end of the cell is fixed to a holding member in a gas tight manner, the one end of the cell is fixed by a fixing material. In addition to being fixed to the holding member, the surface of the fixing member and the surface of the holding member are sealed to gas tight with a sealing material, and crystal glass having high heat resistance and high sealing properties is used. (For example, refer to Patent Document 1).

JP 2005-183376 A

  If the crystallized glass is sealed, high sealing performance can be secured. However, since crystallized glass has poor wettability compared with amorphous glass, it has a problem that seal failure is likely to occur due to poor wettability to the surface of the seal portion.

  The present invention has been made in view of such circumstances, and solves the problem of poor wettability while maintaining the characteristics of crystallized glass having good sealing performance as a sealing material. An object of the present invention is to provide a highly reliable fuel cell that can be reliably shut off.

  In order to achieve this object, the present invention provides a plurality of electrically connected fuel cells that operate when fuel gas and oxidant gas flow from one end to the other end, and the plurality of fuel cells. And a gas manifold for supplying the fuel gas to the fuel cells, and a support portion of the gas manifold at a portion where the plurality of fuel cells are erected Is an insulating support portion that is an insulating member, and includes a seal portion that seals the insulating support portion and a metal placement portion on which the insulating support portion is disposed, the seal portion being a crystal A fuel cell assembly comprising a holding portion for pressing the crystallized glass sealing material.

  The fuel battery cell assembly having this configuration can solve the problem of poor wettability by crushing the crystallized glass sealing material by the pressing portion and expanding the bonding area of the crystallized glass sealing material. That is, since the crystallized glass sealing material spreads over the entire sealing surface, the bonding area increases, and the bonding strength with the member to be sealed can be increased. Therefore, the problem of poor wettability can be solved.

Further, in the fuel cell according to the present invention, a flat plate portion of the insulating support portion is provided above the arrangement portion via the crystallized glass sealing material, and protrudes from the flat plate portion toward the inside of the gas manifold. It can comprise so that it may be provided with the insulating pipe line part to do.
By configuring in this way, the seal part and the holding part can be arranged outside the gas manifold, and since the seal part is not in the gas manifold, it is difficult for the fuel gas fluid in the gas manifold to be disturbed, and gas is supplied to the fuel cells. Can be done smoothly.

Further, in the fuel cell according to the present invention, the pressing portion is configured to be a pressing portion that presses the crystallized glass sealing material using a surface of the flat plate portion of the insulating support portion on the gas manifold side. can do.
By comprising in this way, the load which hold | suppresses the crystallized glass sealing material using the surface by the side of the gas manifold of the flat plate part of an insulating support part can be applied. Therefore, it is not necessary to provide a separate pressing portion in a portion other than the insulating support portion when viewed from the top, such as between the insulating support portions, and the distance between the insulating support portions can be reduced, which contributes to downsizing of the fuel cell assembly. Moreover, since an unnecessary thing is not arrange | positioned around the electrode of a fuel cell, an electrical short can be prevented.

In the fuel cell according to the present invention, the insulating support portion may be provided for each fuel cell.
By comprising in this way, while also carrying out the wettability improvement of a crystallized glass sealing material, a sealing part can be provided for every fuel cell, and the sealing distance which is the length sealed per 1 sealing part is set. Since it can be shortened, the sealing difficulty can be lowered and the sealing accuracy can be increased.

  According to the present invention, a highly reliable fuel cell that solves the problem of poor wettability while maintaining the characteristics of crystallized glass having good sealing performance as a sealing material, and can reliably shut off the gas inside and outside the gas manifold. Can be provided.

FIG. 1 is an overall configuration diagram showing a fuel cell system including a fuel cell according to an embodiment of the present invention. FIG. 2 is a front sectional view showing the fuel cell module of the fuel cell shown in FIG. 3 is a cross-sectional view taken along the line III-III shown in FIG. 4 is a partial cross-sectional view showing a fuel cell unit which is a component of the fuel cell shown in FIG. FIG. 5 is a perspective view showing a fuel cell stack composed of a plurality of fuel cell units shown in FIG. 4 and a seal portion. FIG. 6 is an enlarged cross-sectional view showing a seal portion of the fuel cell assembly which is a part of FIG. FIG. 7 is an enlarged cross-sectional view showing a modification of the seal portion of the present invention. FIG. 8 is a perspective view showing a gas manifold which is a component of the fuel cell shown in FIG. FIG. 9 is a schematic enlarged view of a part of the fuel cell module shown in FIG.

  Next, a fuel cell according to an embodiment of the present invention will be described with reference to the drawings. In addition, embodiment described below is the illustration for demonstrating this invention, and this invention is not limited only to these embodiment. Therefore, the present invention can be implemented in various forms without departing from the gist thereof.

  1 is an overall configuration diagram showing a fuel cell system including a fuel cell according to an embodiment of the present invention, FIG. 2 is a front sectional view showing a fuel cell module of the fuel cell shown in FIG. 1, and FIG. FIG. 4 is a partial cross-sectional view showing a fuel cell unit which is a component of the fuel cell shown in FIG. 2, and FIG. 5 is a plurality of fuel cells shown in FIG. FIG. 6 is a perspective view showing a fuel cell stack composed of units and a seal portion, and FIG. 6 shows a part of the gas seal structure of the fuel cell module and the gas manifold and fuel cell stack shown in FIG. FIG. 7 is an enlarged sectional view, FIG. 7 is an enlarged sectional view showing a modification of the seal portion of the present invention, and FIG. 8 is a perspective view showing a gas manifold which is a component of the fuel cell shown in FIG. In the drawings, for easy understanding, the thickness, size, enlargement / reduction ratio, etc. of each member are not matched with the actual ones.

  The fuel cell system FCS shown in FIG. 1 includes a fuel cell 1 and an auxiliary unit 4.

  The fuel cell 1 includes a fuel cell module 2, a hot water production apparatus 50 connected to the fuel cell module 2 and supplied with exhaust gas discharged from the fuel cell module 2, and a hot water production apparatus connected to the hot water production apparatus 50. A water supply source 24 for supplying tap water to 50, a control box 52 disposed in the fuel cell module 2 for controlling the supply amount of fuel gas supplied to the fuel cell module 2, and the fuel cell module 2 And an inverter 54 that is a power extraction unit (power conversion unit) for supplying the power generated by the fuel cell module 2 to the outside. In the hot water production apparatus 50, the tap water supplied from the water supply source 24 becomes hot water due to the heat of the exhaust gas, and is supplied to a hot water storage tank of an external water heater (not shown).

  The auxiliary unit 4 stores a water from a water supply source 24 such as a water supply and uses a filter to obtain pure water, and a water flow rate adjustment for adjusting the flow rate of the water supplied from the pure water tank 26. A unit 28, a fuel supply source 30 for supplying a fuel gas (reformed gas) such as city gas, a gas shut-off valve 32 for shutting off the fuel gas supplied from the fuel supply source 30, and sulfur from the fuel gas A desulfurizer 36 for removing, a fuel flow rate adjusting unit 38 for adjusting the flow rate of the fuel gas, an air supply source 40 for supplying air as an oxidant, and air supplied from the air supply source 40 are shut off. The solenoid valve 42, the reforming air flow rate adjusting unit 44 and the power generation air flow rate adjusting unit 45 that adjust the flow rate of the air, and the fuel gas and the reforming air flow rate adjustment supplied from the fuel flow rate adjusting unit 38 And a mixing unit 46 for mixing the air supplied reforming the knit 44.

  In the fuel cell system according to the present embodiment, the reforming air supplied to the reformer 20 and the power generation air supplied to the power generation chamber 10 are heated to efficiently raise the temperature at startup. No heating means such as a heater or heating means for separately heating the reformer 20 is provided.

  Next, the internal structure of the fuel cell module 2 will be described. As shown in FIGS. 1 to 3, the fuel cell module 2 includes a housing 6, and the inside of the housing 6 is a sealed space 8. A fuel cell assembly 12 that performs a power generation reaction with a fuel gas (reformed gas) and an oxidizing gas (air) is disposed in a power generation chamber 10 that is a lower portion of the sealed space 8. In addition, a combustion chamber 18 is formed above the power generation chamber 10 in the sealed space 8. In this combustion chamber 18, the remaining fuel gas that has not been used for the power generation reaction and the remaining air burn, and exhaust gas is discharged. It is designed to generate. A reformer 20 for reforming the fuel gas (reformed gas) is disposed above the combustion chamber 18, and reaches a temperature at which the reformer 20 can undergo a reforming reaction by the combustion heat of the residual gas. So that it is heated. Further, an air heat exchanger 22 for receiving combustion heat and heating air is disposed above the reformer 20. A gas manifold 66 is formed below the power generation chamber 10 in the sealed space 8. Further, a metal arrangement portion 160 is formed in the gas manifold.

  The fuel cell assembly 12 includes ten fuel cell stacks 14. As shown in FIG. 5, the fuel cell stack 14 includes 16 fuel cell units 16. With this configuration, the fuel cell assembly 12 includes 160 fuel cell units 16. It will be. Further, the lower end side and the upper end side of the fuel cell unit 16 are respectively supported by a support member 68 and an upper support member 100 which are insulating support portions of the gas manifold. The support member 68 and the upper support member 100 are formed with through holes 68a and 100a through which an inner electrode terminal 86 described later can pass. In the present embodiment, the top plate is a support member 68 in which an opening for supporting the fuel cell unit on the gas manifold is formed. The opening is the through hole 68a.

  The fuel cell unit 16 includes a fuel cell 84 and an inner electrode terminal 86 that is a supported portion connected to each end of the fuel cell 84 in the vertical direction. The inner electrode terminal 86 is made of an oxidation-resistant metal or alloy. The fuel cell 84 is a tubular structure extending in the vertical direction, and includes a cylindrical inner electrode layer 90 that forms a fuel gas flow path 88 therein, a cylindrical outer electrode layer 92, an inner electrode layer 90, and an outer side. An electrolyte layer 94 is provided between the electrode layer 92 and the electrode layer 92. The inner electrode layer 90 is a fuel electrode (anode electrode) through which fuel gas passes, and the outer electrode layer 92 is an air electrode (cathode electrode) in contact with air. The upper part 90 a of the inner electrode terminal 86 has an outer peripheral surface 90 b and an upper end surface 90 c exposed to the electrolyte layer 94 and the outer electrode layer 92. The inner electrode terminal 86 is connected to the outer peripheral surface 90b through a conductive sealing material 96, and is electrically connected to the inner electrode layer 90 by making direct contact with the upper end surface 90c. In addition, a fuel gas passage 98 communicating with the fuel gas passage 88 of the inner electrode layer 90 is formed at the center of the inner electrode terminal 86. The fuel gas passage 98 includes a support member 68 and an upper support. A pipe line part 120 for penetrating the member 100 is formed, and an opening part 121 is formed at the tip of the pipe line part 120. Furthermore, the end surface of the inner electrode terminal 86 is formed as a pressing surface 99 for crushing the crystallized glass sealing material.

  In addition, a current collector 102 and an external terminal 104 are attached to each fuel cell unit 16. The current collector 102 is integrally formed by a fuel electrode connection portion 102 a electrically connected to the inner electrode terminal 86 and an air electrode connection portion 102 b electrically connected to the entire outer peripheral surface of the outer electrode layer 92. Is formed. The external terminal 104 is connected to the external terminal 104 (not shown) of the fuel cell unit 16 at the end of the adjacent fuel cell stack 14 so that all 160 fuel cell units 16 are connected in series. It has become.

The crystallized glass sealing material 301 is pressed by the surface 99 pressed by the inner electrode terminal 86 to seal the fuel cell unit 16 and the support member 68. By crushing the crystallized glass sealing material by the pressing surface 99 and expanding the bonding area of the crystallized glass sealing material, the problem of poor wettability can be solved. That is, since the crystallized glass sealing material spreads over the entire sealing surface, the bonding area increases, and the bonding strength with the member to be sealed can be increased. Therefore, the problem of poor wettability can be solved. The glass sealant used in this embodiment is a _{SiO 2, B 2 O 3,} MgO, CaO, Al 2 O 3, Na 2 O, crystallized glass was _{K 2} O, etc. components.

  Furthermore, the glass sealant 301 is disposed on the upper surface 68 b of the support member 68 that is outside the gas manifold 66. Since the glass sealing material 301 is disposed outside the gas manifold 66, the pressing surface 99 can also be disposed outside the gas manifold, and the sealing material does not partially cover or close the opening. The fuel gas can be supplied into the cell without being disturbed.

  In particular, in this embodiment, a pressing surface 99 is provided on the bottom surface of the fuel cell unit 16. Since the pressing surface 99 is provided on the bottom surface of the fuel cell unit 16, a load for pressing the crystallized glass sealing material using the bottom surface of the fuel cell unit 16 can be applied. Therefore, it is not necessary to provide a separate pressing portion between the fuel cells, and the distance between the fuel cells can be shortened, which contributes to the miniaturization of the fuel cell assembly.

Furthermore, the pipe line part 120 of the fuel cell unit 16 is disposed so as to pass through the glass sealant 301 and the through hole 68a of the support member 68, and the opening part 121 of the pipe line part of the fuel cell unit 16 is a support member. 68 is disposed below the lower surface 68c of the 68. Since the opening 121 of the fuel cell unit 16 is below the glass sealing material 301, the crystallized glass sealing material does not partially cover or block the opening 121, so that the fuel gas is not disturbed. It can be supplied inside the cell.

The crystallized glass sealing material 302 is pressed by the lower surface 68 c of the support member 68 and seals the support member 68 and the arrangement portion 160 of the gas manifold 66. By crushing the crystallized glass sealing material with the lower surface 68c and expanding the bonding area of the crystallized glass sealing material, the problem of poor wettability can be solved. That is, since the crystallized glass sealing material spreads over the entire sealing surface, the bonding area increases, and the bonding strength with the member to be sealed can be increased. Therefore, the problem of poor wettability can be solved.

A modification example shown in FIG. 7 will be described next. In the modified example, the insulating support portion of the gas manifold is formed by the bush 170. The bushing 170 is formed with a holding part 170b for holding down the crystallized glass sealing material using the surface of the flat plate part on the manifold side. Further, an insulative duct portion 130 is formed that protrudes from the flat plate portion of the bush 170 toward the inside of the gas manifold. By crushing the crystallized glass sealing material with the pressing portion 170b and expanding the bonding area of the crystallized glass sealing material, the problem of poor wettability can be solved. That is, since the crystallized glass sealing material spreads over the entire sealing surface, the bonding area increases, and the bonding strength with the member to be sealed can be increased. Therefore, the problem of poor wettability can be solved.

Furthermore, the crystallized glass sealing material 302 is disposed in the metal placement portion 160 of the gas manifold 66. Since the glass sealant 302 is arranged in the arrangement part 160, the holding part 170b can be similarly arranged outside the gas manifold, and the sealing part and the holding part can be arranged outside the gas manifold, and the sealing part is not inside the gas manifold. The fuel gas fluid in the gas manifold is less likely to be disturbed, and the gas can be supplied smoothly to the cell.

In the present modification, the pressing portion 170 b is provided on the bottom surface of the bush 170. By providing the pressing portion 170b on the bottom surface of the bush 170, a load for pressing the crystallized glass sealing material using the pressing portion 170b can be applied. Therefore, it is not necessary to provide a separate pressing portion in a portion other than the insulating support portion when viewed from the top, such as between the insulating support portions, and the distance between the insulating support portions can be reduced, which contributes to downsizing of the fuel cell assembly. Moreover, since an unnecessary thing is not arrange | positioned around the electrode of a fuel cell, an electrical short can be prevented.

Furthermore, in this modification, one bush 170 is provided for the fuel cell unit 16 including one fuel cell. By providing one bush 170 with respect to the fuel cell unit 16 having one fuel cell, a seal portion can be provided for each fuel cell, and the seal distance per seal portion can be shortened. Therefore, the sealing difficulty can be reduced and the sealing accuracy can be increased.

  Further, in this embodiment, 16 fuel cell units are provided for one support member 68 in order to improve workability. However, as a modification, in order to make the ceramic support member difficult to break, a support member is provided. One fuel cell unit can be supported by one support member. Furthermore, in this embodiment, the bottom surface of the fuel cell unit 16 functions as a pressing portion.

  The reformer 20 has a pure water introduction pipe 60 for introducing pure water to the upstream end side thereof, and a to-be-reformed gas introduction pipe 62 for introducing reformed fuel gas and reforming air. It is attached. Inside the reformer 20, an evaporator 20a and a reformer 20b are formed in order from the upstream side, and the reformer 20b is filled with a reforming catalyst. The fuel gas and air mixed with the steam (pure water) introduced into the reformer 20 are reformed by the reforming catalyst filled in the reformer 20. As the reforming catalyst, a catalyst obtained by imparting nickel to the alumina sphere surface or a catalyst obtained by imparting ruthenium to the alumina sphere surface is appropriately used. A fuel gas supply pipe 64 extending downward is connected to the downstream end side of the reformer 20.

  The air heat exchanger 22 includes an air aggregation chamber 70 on the upstream side and two air distribution chambers 72 on the downstream side. The air aggregation chamber 70 and the air distribution chamber 72 are separated by six air flow channel tubes 74. It is connected. Here, as shown in FIG. 3, three air flow path pipes 74 form a set (74a, 74b, 74c, 74d, 74e, 74f), and the air in the air collecting chamber 70 is in each set. It flows into each air distribution chamber 72 from the air flow path pipe 74. The air flowing through the six air flow path tubes 74 of the air heat exchanger 22 is preheated by the exhaust gas that burns and rises in the combustion chamber 18. An air introduction pipe 76 is connected to each of the air distribution chambers 72. The air introduction pipe 76 extends downward, and the lower end side communicates with the lower space of the power generation chamber 10, and the air that has been preheated in the power generation chamber 10. Is introduced.

  As shown in FIG. 8 in particular, the gas manifold 66 has a substantially rectangular parallelepiped shape with a bottom surface 67 having a substantially rectangular shape, and a plate for supporting the fuel cell stack 14 is provided above the gas manifold 66. A support member 68 is disposed. The support member 68 is formed with a through hole 69 for supplying the fuel gas accommodated in the gas manifold 66 to the fuel gas flow path 88 of each fuel cell 84. The support member 68 is disposed so as to face the bottom surface 67, and thus the bottom surface 67 serves as a facing wall disposed so as to face the support member 68.

  Further, inside the gas manifold 66, an internal gas supply pipe 63 for supplying fuel gas into the gas manifold 66 is disposed with a predetermined distance from each of the bottom surface 67 and the support member 68. The internal gas supply pipe 63 has a circular cross section perpendicular to the axial direction, and the axial core is parallel to the bottom surface 67 along the longitudinal direction of the gas manifold 66 (the long side direction of the substantially rectangular shape). 2, 3, and 8, the distance from the support member 68 is disposed at a position (height) that is longer than the distance from the bottom surface 67. Further, one end of the internal gas supply pipe 63 is connected to a fuel gas supply pipe 64 connected to the downstream end side of the reformer 20 as shown in FIG. The fuel gas is supplied from the mass device 20 through the fuel gas supply pipe 64. On the other hand, the other end of the internal gas supply pipe 63 is fixed to the inner wall (the right inner wall in FIG. 2) of the gas manifold 66, as shown in FIGS.

  Furthermore, the internal gas supply pipe 63 is formed with a plurality of injection holes 65 for vertically discharging the fuel gas (reformed fuel gas) supplied into the internal gas supply pipe 63 toward the bottom surface 67. Has been. As shown in FIGS. 2, 3, and 9, these ejection holes 65 are formed in a straight line on the lower surface of the internal gas supply pipe 63 at intervals from each other along the axial direction.

  An exhaust gas chamber 78 is formed below the gas manifold 66, and an exhaust gas passage 80 extending in the vertical direction is formed inside the front surface 6a and the rear surface 6b, which are surfaces along the longitudinal direction of the housing 6. (See FIG. 3). The upper end side of the exhaust gas passage 80 communicates with the space in which the air heat exchanger 22 is disposed, and the lower end side communicates with the exhaust gas chamber 78. Further, an exhaust gas discharge pipe 82 is connected to substantially the center of the lower surface of the exhaust gas chamber 78, and the downstream end of the exhaust gas discharge pipe 82 is connected to the hot water production apparatus 50. Further, the combustion chamber 18 is provided with an ignition device 83 for starting combustion of fuel gas and air.

  In the start-up mode of the fuel cell system FCS in the present embodiment, combustion operation, partial oxidation reforming reaction (POX), first autothermal reforming reaction (ATR1), and second autothermal reforming reaction (ATR2) And the steam reforming reaction (SR) are sequentially switched and the reforming reaction proceeds.

The partial oxidation reforming reaction (POX) is a reforming reaction performed by supplying a reformed gas and air to the reformer 20, and the reaction shown in the chemical reaction formula (1) proceeds.
_{C m H n + xO 2 →} aCO 2 + bCO + cH 2 (1)
Since this partial oxidation reforming reaction (POX) is an exothermic reaction, its startability is high, and is a suitable reforming reaction at the beginning of starting the fuel cell system FCS. However, the partial oxidation reforming reaction (POX) is theoretically low in hydrogen yield and difficult to control the exothermic reaction. This is a preferred reforming reaction.

The steam reforming reaction (SR) is a reforming reaction performed by supplying the reformed gas and steam to the reformer 20, and the reaction shown in the chemical reaction formula (2) proceeds.
_{C m H n + xH 2 O} → aCO 2 + bCO + cH 2 (2)
The steam reforming reaction (SR) has the highest hydrogen yield and is a highly efficient reaction. However, since the steam reforming reaction (SR) is an endothermic reaction, a heat source is required and is a suitable reforming reaction at a stage where the temperature has risen to some extent from the beginning of the start of the fuel cell system FCS.

The autothermal reforming reaction (ATR) comprising the first autothermal reforming reaction (ATR1) and the second autothermal reforming reaction (ATR2) is a partial oxidation reforming reaction (POX) and a steam reforming reaction (SR). Is a reforming reaction that is performed by supplying the reformed gas, air, and water vapor to the reformer 20, and the reaction shown in the chemical reaction formula (3) proceeds. .
_{C m H n + xO 2 +} yH 2 O → aCO 2 + bCO + cH 2 (3)
Autothermal reforming reaction (ATR) is a combined use of partial oxidation reforming reaction (POX) and steam reforming reaction (SR) in hydrogen yield, and it is easy to balance reaction heat. POX) is a reforming reaction suitable as a reaction that connects the steam reforming reaction (SR). In the present embodiment, the first autothermal reforming reaction (ATR1) closer to the partial oxidation reforming reaction (POX) is performed by supplying a small amount of water, and the water is supplied to increase after the temperature rises. Then, the second autothermal reforming reaction (ATR2) closer to the steam reforming reaction (SR) is performed later.

  Next, the startup mode of the fuel cell system FCS will be described. First, the power generation air flow rate adjusting unit 45, the electromagnetic valve 42 and the mixing unit 46 are controlled so as to increase the reforming air, and air is supplied to the reformer 20. Further, as described above, power generation air is supplied to the power generation chamber 10 from the air introduction pipe 76. Further, the fuel flow rate adjusting unit 38 and the mixing unit 46 are controlled so as to increase the supply of the fuel gas, the reformed gas is supplied to the reformer 20, and the reformed gas sent to the reformer 20 is supplied. The reforming air is sent into each fuel cell unit 16 from each through hole 69 via the reformer 20, the fuel gas supply pipe 64, the internal gas supply pipe 63, and the gas manifold 66. The reformed gas and reforming air sent into each fuel cell unit 16 pass through the fuel gas channel 88 from the fuel gas channel 98 formed at the lower end of each fuel cell unit 16, The fuel gas flows out from the fuel gas passage 98 formed at the upper end. Thereafter, the gas to be reformed that has flowed out from the upper end of the fuel gas flow path 98 is ignited by the ignition device 83 to perform the combustion operation. As a result, the gas to be reformed is combusted in the combustion chamber 18, and the partial oxidation reforming reaction (POX) described above is generated.

  Thereafter, on the condition that the temperature of the reformer 20 is about 600 ° C. or higher and the temperature of the fuel cell assembly 12 exceeds about 250 ° C., the first autothermal reforming reaction (ATR1) described above is performed. And the transition to the second autothermal reforming reaction (ATR2) is performed on the condition that the temperature of the fuel cell assembly 12 exceeds about 400 ° C. At this time, the water flow rate adjusting unit 28, the fuel flow rate adjusting unit 38, and the reforming air flow rate adjusting unit 44 supply the reformer 20 with a gas in which the gas to be reformed, the reforming air, and the steam are previously mixed. . Next, the steam reforming reaction (SR) is performed on the condition that the temperature of the reformer 20 becomes 650 ° C. or higher and the temperature of the fuel cell assembly 12 exceeds about 600 ° C.

  As described above, the temperature in the power generation chamber 10 gradually increases by switching the reforming process in accordance with the progress of the combustion process from ignition. When the temperature of the power generation chamber 10 reaches a predetermined power generation temperature lower than the rated temperature (about 700 ° C.) at which the fuel cell module 2 is stably operated, the electric circuit including the fuel cell module 2 is closed. As a result, the fuel cell module 2 can start power generation, and current can flow through the circuit to supply power to the outside. Due to the power generation of the fuel cell 84, the fuel cell 84 itself also generates heat, and the temperature of the fuel cell 84 rises, so that the rated temperature for operating the fuel cell module 2, for example, 700 to 800 ° C. is reached.

  In this ignition to combustion process, the gas to be reformed and the reformed gas (fuel gas) supplied to the internal gas supply pipe 63 through the fuel gas supply pipe 64 are introduced into the gas manifold 66 from the respective ejection holes 65. Erupted. At this time, the internal gas supply pipe 63 is disposed inside the gas manifold 66, and the inside of the gas manifold 66 is hotter than the outside, so the gas supply pipe is disposed outside the gas manifold. Compared to the case, the heat radiation of the fuel gas can be reduced. Therefore, the heat radiation of the reaction gas when supplying the reaction gas to the gas manifold can be reduced. For this reason, high-temperature fuel gas can be supplied to the fuel battery cell 84 and the temperature rise of the fuel battery cell 84 can be promoted or the temperature drop can be suppressed, so that power generation can be performed efficiently. it can.

  Furthermore, in the present embodiment, the case where the fuel cell 84 in which the inner electrode layer 90 is a fuel electrode (anode electrode) and the outer electrode layer 92 is an air electrode (cathode electrode) is disposed has been described. Not limited to this, a fuel cell in which the inner electrode layer 90 is an air electrode (cathode electrode) and the outer electrode layer 92 is a fuel electrode (anode electrode) may be disposed as desired. In this case, air (oxidant gas) may be supplied to the internal gas supply pipe 63.

  DESCRIPTION OF SYMBOLS 1 ... Fuel cell, 2 ... Fuel cell module, 10 ... Power generation chamber, 16 ... Fuel cell unit, 20 ... Reformer, 63 ... Internal gas supply piping, 65, 165 ... Injection hole, 66 ... Gas manifold, 67 ... Bottom surface 68 ... Support member 69 ... Through hole 88 ... Fuel gas flow path 163 ... Branch pipe FCS ... Fuel cell system 201 ... Partition wall 202 ... Space 301, 302 ... Crystallized glass sealant

Claims (4)

A plurality of electrically connected fuel cells that operate when the fuel gas and the oxidant gas flow from one end side to the other end side; and
A plurality of fuel cells standing upright, and a gas manifold for supplying the fuel gas to the fuel cells,
A fuel cell assembly comprising:
The support portion of the gas manifold in the portion where the plurality of fuel cells are erected is an insulating support portion that is an insulating member,
A seal portion that seals the insulating support portion and a metal placement portion on which the insulating support portion is disposed;
The sealing portion is a crystallized glass sealing material;
A fuel cell assembly comprising a pressing portion for pressing the crystallized glass sealing material. A flat plate portion of the insulating support portion is provided on the upper side of the arrangement portion via the crystallized glass sealing material, and an insulating pipe portion protruding from the flat plate portion toward the inside of the gas manifold is provided. The fuel ionization cell assembly according to claim 1, wherein 3. The fuel cell assembly according to claim 2, wherein the pressing portion is a pressing portion that presses the crystallized glass sealing material using a surface of the flat plate portion of the insulating support portion on the gas manifold side. body. The fuel cell assembly according to claim 3, wherein the insulating support portion is provided for each fuel cell.

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