JP7137459B2 - fuel cell module - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fuel cell module, and more particularly to a fuel cell module that generates power by reacting supplied fuel gas and oxidant gas.

2. Description of the Related Art Conventionally, as a fuel cell module that generates power by reacting supplied fuel gas and oxidant gas, for example, one described in Patent Document 1 is known.
The conventional fuel cell module described in Patent Document 1 includes a fuel cell stack, a combustor, and a reformer, which are housed in a housing.
Further, in the conventional fuel cell module described above, the fuel cell stack is a laminated fuel cell stack formed by stacking a plurality of fuel cells, and each fuel cell is composed of an oxide ion conductor. A cathode electrode and an anode electrode are provided on both sides of a flat plate-like electrolyte. Furthermore, a cathode separator and an anode separator are arranged between each fuel cell. Furthermore, the cathode separator is formed with an oxidant gas channel for supplying the oxidant gas to the cathode electrode, and the anode separator is formed with a fuel gas channel for supplying the fuel gas to the anode electrode.

A plurality of fuel cells, cathode separators, and anode separators stacked in this way are sandwiched between the upper end plate and the lower end plate from both ends, and are pressed and fixed in the stacking direction. Further, the lower end plate is provided with an oxidizing gas inlet for supplying oxidizing gas to each fuel cell and a fuel gas inlet for supplying fuel gas to each fuel cell. The lower end plate further includes an oxidant gas outlet for discharging the remaining oxidant gas that is supplied to the cathode electrode of each fuel cell and not used for power generation, and an oxidant gas outlet that is supplied to the anode electrode of each fuel cell, A fuel gas outlet is provided for discharging the remaining fuel gas that has not been used for power generation.

The remaining fuel gas that has flowed out from the fuel gas outlet and the remaining oxidant gas that has flowed out from the oxidant gas outlet are guided to a combustor disposed within the housing, where they are burned. Combustion heat generated in the combustor exchanges heat with the oxidizing gas flowing through the oxidizing gas passages arranged on both side surfaces of the housing. The oxidant gas whose temperature is raised by heat exchange is introduced into the fuel cell stack through the oxidant gas introduction port. As a result, the temperature of the fuel cell stack is raised to a temperature at which power generation reaction is possible. As described above, in the fuel cell module described in Patent Document 1, the remaining fuel gas is burned with the remaining oxidant gas in the combustor arranged in the housing, and the fuel cell stack is driven by the generated combustion gas. By indirectly heating the fuel cell stack, the fuel cell stack is efficiently heated to a temperature at which power generation reaction is possible, and that temperature is maintained.

Further, in the above-described conventional fuel cell module, the stacked fuel cell stack is generally housed inside an outer container member such as a housing, and the power generated in the fuel cell is taken out. A conductive bus bar penetrates the outer shell member and is taken out to the outside.

JP 2017-50192 A

However, the conventional fuel cell module described in the above-mentioned Patent Document 1 includes an outer container member that accommodates the fuel cell stack, and has a structure in which the bus bar passes through the outer container member. A structure is required to electrically insulate between the outer shell member and the outer shell member.
Also, in order to accommodate the fuel cell stack in the outer shell member, a structure that takes into account design errors and thermal expansion differences between the two is required.
Therefore, in order to secure these necessary structures, there is a problem that the number of parts increases, the processing cost increases, and the size and weight increase, resulting in an increase in manufacturing cost.
In addition, there is also the problem that an increase in the number of parts may result in an increase in electrical resistance.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a fuel cell module capable of suppressing manufacturing costs and suppressing electrical resistance. and

In order to solve the above-described problems, the present invention provides a fuel cell module that generates power by reacting supplied fuel gas and oxidant gas, wherein flow paths for the fuel gas and oxidant gas are defined respectively. A closed-type fuel cell stack, a reformer that reforms a raw fuel gas to generate a hydrogen-containing fuel gas and supplies the fuel gas to the fuel cell stack, and a fuel cell stack that is used for power generation in the fuel cell stack. The fuel cell module has a combustor that burns the residual fuel gas left without the The base end side of the bus bar is provided in the fuel cell stack, and the front end side of the bus bar does not pass through the outer shell container member. It is characterized by protruding to the outside of the module so that it can be taken out directly.
In the present invention configured as described above, first, since an outer container member for housing the closed-type fuel cell stack is not provided, the base end side of the bus bar can be easily provided in the fuel cell stack. .
Further, when the fuel cell stack is accommodated in the outer container member, the structure that takes into account design errors and thermal expansion differences between the two can be omitted by eliminating the outer container member.
Furthermore, since the front ends of the busbars can protrude so as to be directly removable from the outside of the fuel cell module without penetrating the outer shell member, the structure electrically insulates between the outer shell member and the busbars. and parts can be omitted.
As a result, by suppressing the number of parts, the manufacturing cost can be suppressed and the electrical resistance can also be suppressed.

In the present invention, preferably, furthermore, a housing having a space for accommodating the reformer and the combustor formed therein, and a heat insulator disposed so as to thermally isolate the fuel cell stack from the housing. and a base end side of the bus bar is restrained by the heat insulating material.
In the present invention configured as described above, the heat insulating material can reduce the heat directly transmitted between the fuel cell stack and the housing. As a result, it is possible to further reduce the influence of changes in the arrangement of the reformer, combustor, etc. in the housing on the temperature distribution of the fuel cell stack.
In addition, since the base end side of the busbar provided at the end of the fuel cell stack can be restrained by the heat insulating material, the busbar can be stably held without penetrating the outer shell member.

In the present invention, preferably, the fuel cell stack is surrounded by the heat insulating material.
In the present invention configured as described above, it is possible to further effectively reduce the influence of changes in the arrangement of the reformer, combustor, etc. in the housing on the temperature distribution of the fuel cell stack.

In the present invention, preferably, the heat insulating material is a non-conductive insulator, and the base end of the bus bar is a fixed end covered with the heat insulating material and fixed to the end of the fuel cell stack. The tip of the bus bar is a free end that protrudes to the outside of the heat insulating material and is not restrained by the heat insulating material.
In the present invention configured as described above, the base end portion of the bus bar is a fixed end portion fixed to the end portion of the fuel cell stack and directly or indirectly restrained by the heat insulating material. Heat transfer between the fixed end and its surrounding portion can be suppressed by the heat insulating material.
Moreover, since the heat insulating material is a non-conductive insulator, it is possible to electrically insulate between the fixed end portion of the bus bar and its peripheral portion.
Furthermore, in addition to the fact that the outer shell member is not provided, the tip of the bus bar protrudes to the outside of the heat insulating material, so that it becomes a free end that is not restrained by the heat insulating material. As a result, the position of the free end of the busbar can be changed according to the position of the fixed end of the busbar fixed to the end of the fuel cell stack, thereby increasing the degree of freedom in design.
Therefore, when the power generated in the fuel cell is directly taken out of the fuel cell module by the busbar, the position and direction of power takeout can be freely set according to the position of the free end of the busbar. can.

In the present invention, preferably, the free end of the bus bar includes a wire connection portion to which an electric wire is connected, and the heat insulating material prevents deformation of the bus bar while the electric wire is connected to the wire connection portion. It is a cushioning material that suppresses
In the present invention configured as described above, the heat insulating material can function as a cushioning material that suppresses deformation of the bus bar in a state where the electric wire is connected to the electric wire connection portion of the free end of the bus bar.
In other words, even if a deformation load or the like is applied to the free end of the busbar due to the weight and elastic force of the electric wire, and the busbar itself is slightly deformed, the heat insulating material acts as a cushioning material that suppresses the deformation of the busbar. , busbars and fuel cell stacks can be protected from damage.

In the present invention, preferably, the bus bar has a front surface or a back surface parallel to a stacking surface on which the plurality of flat fuel cells of the closed fuel cell stack are stacked. It is arranged on the outer surface of the outermost flat plate type fuel cell in the fuel cell stack.
In the present invention configured as described above, the bus bar is arranged such that the front surface or the rear surface of the fuel cell stack is parallel to the stacking surface on which the plurality of flat fuel cells are stacked. can be arranged on the outer surface of the outermost flat plate type fuel cell.
Thereby, the bus bar can be easily assembled to the end portion of the fuel cell stack, and the structure can be simplified.

In the present invention, preferably, the bus bar is formed in a plate-like shape from its base end portion to its longitudinal tip portion, and is arranged such that its front surface or rear surface is a vertical plane.
If the front or back surface of the busbar formed in a plate shape from the base end to the tip in the longitudinal direction is arranged so as to be horizontal, the electric wire is connected to the electric wire connection portion of the free end of the busbar. In this state, a downward deformation load (bending load, bending load, etc.) acts on the free end of the busbar due to the weight of the electric wire or the like, so that the busbar itself is likely to be deformed.
On the other hand, in the present invention, a downward deformation load (bending load, deflection load, etc.) is applied to the free end of the busbar due to the weight of the wire, etc., in a state where the wire is connected to the wire connection portion of the free end of the busbar. ), the front or rear surface of the bus bar can be arranged in a vertical plane.
This makes it possible to increase the rigidity (bending rigidity, deflection rigidity, etc.) of the busbar against downward deformation load (bending load, deflection load, etc.) compared to the case where the front surface or back surface of the busbar is arranged in a horizontal plane.
Therefore, deformation (bending deformation, bending deformation, etc.) of the busbar can be suppressed when the electric wire is connected to the electric wire connection portion of the free end of the busbar, reducing the risk of damage to the busbar due to excessive deformation. can do.

In the present invention, preferably, each of the plurality of flat plate-type fuel cells is horizontally stacked with each other such that the stacking surfaces are vertical surfaces.
In the present invention configured as described above, each of the plurality of flat-plate-type fuel cells is stacked horizontally so that the stacking surfaces of the flat-plate-type fuel cells are vertical surfaces. Simply assembling the front or rear surface of the busbar to the outer surface of the battery cell allows them to be placed in the vertical plane.
Therefore, the busbar can be easily assembled to the end of the fuel cell stack. Further, by rotating and positioning the busbar in the vertical plane, it is possible to freely set the position and direction of power extraction from the busbar.

Preferably, the present invention further includes a cover member provided outside the heat insulating material, and the cover member is configured to hold the heat insulating material.
In the present invention configured as described above, the heat insulating material can be reliably held by the cover member, so that the bus bar and the fuel cell stack can be reliably protected from damage.

Advantageous Effects of Invention According to the fuel cell module of the present invention, it is possible to reduce manufacturing costs and electric resistance.

1 is a schematic configuration diagram of an entire fuel cell module according to a first embodiment of the present invention; FIG. 1 is a perspective view of a fuel cell module according to a first embodiment of the invention; FIG. 1 is a front sectional view of a fuel cell module according to a first embodiment of the invention; FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3; FIG. FIG. 4 is a cross-sectional view taken along line VV of FIG. 3; 4 is a cross-sectional view taken along line VI-VI of FIG. 3; FIG. FIG. 8 is a schematic front view of the entire fuel cell module according to the second embodiment of the present invention, with the heat insulating material and the end plate on the front side removed. FIG. 8 is an enlarged perspective view of a bus bar portion in the fuel cell module according to the second embodiment of the present invention shown in FIG. 7;

A fuel cell module according to a first embodiment of the present invention will now be described with reference to the accompanying drawings.
FIG. 1 is a schematic configuration diagram of the entire fuel cell module according to the first embodiment of the present invention.

<Schematic configuration and operation of fuel cell module>
As shown in FIG. 1, a fuel cell module 1 according to the first embodiment of the present invention includes a fuel cell stack 2 that performs a power generation reaction, a fuel gas obtained by reforming raw fuel gas, and a fluid supply device 4 for supplying air, which is a heated oxidant gas.
First, the fuel cell stack 2 is a so-called "stacked fuel cell stack" configured by vertically stacking a plurality of flat fuel cells 2a.
The fuel cell stack 2 is also a so-called "sealed fuel cell stack" in which a fuel gas flow path and an oxidant gas flow path are defined in a sealed chamber.

The fluid supply device 4 also includes a housing 6 , which is vertically arranged above the fuel cell stack 2 . The fuel cell stack 2 and the housing 6 are surrounded by a heat insulating material 8 , which is also provided between the fuel cell stack 2 and the housing 6 .
Thereby, the fuel cell stack 2 is thermally isolated from the housing 6 (fluid supply device 4).
A cover member A1 (see FIG. 1) is provided outside the heat insulating material 8 surrounding the fuel cell stack 2 and the housing 6. As shown in FIG.
Here, in this specification, a closed container that allows the inflow and outflow of air, water, fuel gas, etc. is defined as an "outer container member".
Note that the cover member A1 merely holds the heat insulating material 8 from the outside, and is not an outer container member.
Therefore, in the fuel cell module 1 of this embodiment, an outer container member, which is a closed container, is not provided.

A reformer 36 and a combustor 38 are housed in a space sealed by the housing 6 .
In addition, in FIG. 1, the heat insulating material 8 is described as a continuous material, but it may be composed of a plurality of heat insulating materials. For example, the heat insulating material surrounding the fuel cell stack 2 and the housing 6 and the heat insulating material provided between the fuel cell stack 2 and the housing 6 may be different heat insulating materials.
Furthermore, the heat insulating material may be used by combining a plurality of members having different heat insulating performances, and the method of stacking and arranging the members can be appropriately designed according to the required specifications.
Moreover, the heat insulating material provided between the fuel cell stack 2 and the housing 6 does not necessarily have to completely cover the space between the fuel cell stack 2 and the housing 6, and at least partially It is effective by arranging it.

The reformer 36 is configured to steam-reform the raw fuel gas supplied from the outside of the fluid supply device 4 to generate a hydrogen-rich fuel gas.
The fuel gas produced in the reformer 36 is sent to the fuel cell stack 2 and used in the fuel cell stack 2 for power generation. This fuel gas is supplied to the fuel cell stack 2 through a fuel supply passage 12 extending between the housing 6 of the fluid supply device 4 and the fuel cell stack 2 .
Here, since the housing 6 of the fluid supply device 4 is surrounded by the heat insulating material 8 , the fuel supply passage 12 for supplying the fuel gas extends through the heat insulating material 8 to the fuel cell stack 2 .

The combustor 38 is configured to burn residual fuel that remains in the fuel cell stack 2 without being used for power generation.
The fuel remaining in the fuel cell stack 2 without being used for power generation is discharged to the housing 6 side through the fuel discharge passage 14 extending between the housing 6 of the fluid supply device 4 and the fuel cell stack 2 . It's becoming This fuel discharge passage 14 also extends from the fuel cell stack 2 to the fluid supply device 4 through the heat insulating material 8 surrounding the housing 6 of the fluid supply device 4 .
The residual fuel discharged to the housing 6 side is combusted by the combustor 38 accommodated in the housing 6 to heat the reformer 36 arranged above the combustor 38 . As a result, a reforming catalyst (not shown) in the reformer 36 is heated to a temperature at which steam reforming is possible.

On the other hand, air, which is an oxidant gas for power generation, is also supplied to the fluid supply device 4 from the outside. Then, this air is heated by the combustion heat of the combustor 38 and supplied to the fuel cell stack 2 in a high temperature state.
The fuel cell stack 2 is heated to a temperature at which power generation reaction is possible mainly by the heat of the air for power generation heated to a high temperature.
The air for power generation heated in the fluid supply device 4 is supplied to the fuel cell stack 2 through an oxidant gas supply passage 16 extending from the housing 6 . This oxygen-containing gas supply passage 16 also penetrates the heat insulating material 8 surrounding the housing 6 of the fluid supply device 4 and extends from the fluid supply device 4 to the fuel cell stack 2 .

Also, the remaining air that has been supplied to the fuel cell stack 2 and has not been used for power generation is discharged to the housing 6 side through the oxidant gas discharge passage 18 .
This oxygen-containing gas discharge passage 18 also extends from the fuel cell stack 2 to the fluid supply device 4 through the heat insulating material 8 surrounding the housing 6 of the fluid supply device 4 .
The residual air discharged to the housing 6 side is used for combustion in the combustor 38 inside the housing 6 . Combustion gas generated by combustion is discharged from the fluid supply device 4 as exhaust gas.

Thus, in the fuel cell module 1 of the embodiment of the present invention, the residual fuel gas is combusted by the residual air in the combustor 38 of the fluid supply device 4, and the combustion heat heats the reformer 36. It has become.
On the other hand, the reformer 36 and the combustor 38 are accommodated within the housing 6 of the fluid supply device 4 , and the housing 6 is thermally separated from the fuel cell stack 2 by the heat insulating material 8 .
As a result, the fuel cell stack 2 is substantially not directly heated by the combustion heat of the residual fuel. That is, the heat transfer between the fluid supply device 4 (housing 6) side and the fuel cell stack 2 is substantially performed only by the fluid flowing between them, and the radiant heat radiated from the combustor 38 etc. For example, the fuel cell stack 2 is not directly heated.
Therefore, the temperature of the fuel cell stack 2 can be substantially defined only by the flow rate and temperature of the fluid supplied thereto.

The devices used together with the fuel cell module include an evaporator that generates steam for steam reforming, a desulfurizer that removes the sulfur component contained in the raw fuel gas, and a combustor that removes carbon monoxide from the exhaust gas. Catalytic devices, etc., can also be accommodated within the housing.
Alternatively, these devices can be placed outside the housing and covered with thermal insulation and heated by the heat of the exhaust gases exiting the housing.

Next, the configuration of the fuel cell module according to the first embodiment of the present invention will be described in detail with reference to FIGS. 2 to 6. FIG.
First, FIG. 2 is a perspective view of a fuel cell module according to a first embodiment of the invention. Next, FIG. 3 is a front sectional view of the fuel cell module according to the first embodiment of the present invention. 4 is a cross-sectional view taken along line IV-IV of FIG. 3. FIG. Further, FIG. 5 is a cross-sectional view taken along line VV of FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 3. FIG.
In FIG. 2, a heat insulating material surrounding the fuel cell stack and the like is omitted.

<Overall Configuration of Fuel Cell Module>
As shown in FIG. 2, the fuel cell module 1 according to this embodiment includes a fuel cell stack 2 that performs a power generation reaction, a fuel gas obtained by reforming raw fuel gas, and a heated oxidant. and a fluid supply device 4 for supplying air, which is a gas. The fluid supply device 4 is composed of an evaporator 4a and a reformer/heater 4b. The evaporator 4a is configured to evaporate the supplied water to generate steam and to mix the steam with the raw fuel gas. The gas is steam-reformed to generate a hydrogen-containing fuel gas, which is supplied to the fuel cell stack 2 .

Further, the reformer/heater 4b is covered with a substantially rectangular parallelepiped metal housing 6, and the fuel cell stack 2, the housing 6 of the reformer/heater 4b arranged above it, and the evaporator 4a. are arranged vertically. The fuel cell stack 2, the housing 6, and the evaporator 4a are each surrounded by a heat insulating material 8, so that the fuel cell stack 2 is thermally isolated from the housing 6 and the evaporator 4a.

<Structure of fuel cell stack>
As shown in FIGS. 2 and 3, in this embodiment, the fuel cell stack 2 is a flat plate cell stack, and is configured by stacking a plurality of rectangular flat plate fuel cells 2a.
That is, each fuel cell 2a is configured by providing a fuel electrode and an air electrode (oxidant gas electrode) on both sides of a flat electrolyte made of an oxide ion conductor. Separators are arranged between the cells 2a (not shown).
A top end plate 10a is arranged at the upper end of the plurality of stacked fuel cells 2a, and a bottom end plate 10b is arranged at the lower end. Inside the fuel cell stack 2 obtained by stacking a plurality of fuel cells 2a in this way, a fuel gas supply passage (not shown) for supplying fuel gas to each fuel cell 2a, An oxidizing gas supply passage (not shown) is formed for supplying air, which is an oxidizing gas.
Furthermore, two bus bars B1 and B2 extend from the top and bottom of the fuel cell stack 2 for taking out the generated electric power.

Next, as shown in FIGS. 2 and 3, these busbars B1 and B2 are composed of a pair of upper and lower busbars B1 and B2, each of which is made of a long plate-like conductive member such as metal.
In addition, the base end portion of the upper bus bar B1 is provided between the upper end surface of the fuel cell 2a at the top of the fuel cell stack 2 and the bottom surface of the top end plate 10a.
On the other hand, the base end portion of the lower bus bar B2 is provided between the lower end surface of the lowest fuel cell 2a of the fuel cell stack 2 and the upper surface of the bottom end plate 10b.
That is, each bus bar B1, B2 is connected to the outer surface of the outermost flat plate-type fuel cell 2a in the fuel cell stack 2 (the upper surface of the uppermost fuel cell 2a (uppermost end surface E1) and the lowermost fuel cell). It is arranged on the bottom surface (bottom end surface E2) of the cell 2a.
As a result, as shown in FIGS. 2 and 3, in each of the bus bars B1 and B2, each surface (upper surface S1 , S3) and the rear surface (lower surfaces S2, S4) are arranged in parallel.
Further, the ends of the busbars B1 and B2 are arranged in a horizontal direction (more specifically, each shown in FIG. 2 and FIG. The busbars B1 and B2 protrude rightward when viewed from the front side.

Next, as shown in FIG. 3, the heat insulating material 8 is a non-conductive insulator, and each of the bus bars B1 and B2 is surrounded by the heat insulating material 8 from the base end side to the vicinity of the longitudinal middle portion. is directly or indirectly bound by
As a result, the base ends of the bus bars B1 and B2 are fixed respectively to the top end and bottom end of the fuel cell 2a of the fuel cell stack 2, and are directly or indirectly It has a constrained fixed end.
On the other hand, the ends of the busbars B1 and B2 protrude to the outside of the heat insulating material 8 and are free ends that are not restrained by the heat insulating material 8. As shown in FIG.

Next, as shown in FIGS. 2 and 3, wire connection portions (terminal holes C1 and C2) are provided at the distal end portions (free end portions) of the bus bars B1 and B2.
Wires from a harness (not shown) in which a plurality of wires or cables are bundled are connected to the tip portions (free ends) of the bus bars B1 and B2 including the wire connection portions (terminal holes C1 and C2). connection terminal.
Further, in a state in which the electric wires are connected to the electric wire connection portions (terminal holes C1 and C2) of the bus bars B1 and B2, the weight of the harness (not shown) and the like is applied to the tips (free ends) of the bus bars B1 and B2. However, the heat insulating material 8 functions as a cushioning material that suppresses such deformation (bending deformation or deflection deformation) of the busbars B1 and B2. is also

Furthermore, a fuel supply passage 12, a fuel discharge passage 14, an oxidant gas supply passage 16, and an oxidant gas discharge passage 18 are connected to the top end plate 10a of the fuel cell stack 2, respectively.
These four passages extend into the space sandwiched between the fuel cell stack 2 and the housing 6 of the reformer/heater 4b.
That is, these passages extend upward from the upper surface of the top end plate 10a of the fuel cell stack 2 and are connected to the bottom surface, which is a single surface, of the housing 6 disposed above the fuel cell stack 2. .
Therefore, the fuel supply passage 12, the fuel discharge passage 14, the oxidant gas supply passage 16, and the oxidant gas discharge passage 18 pass through the heat insulating material 8 arranged between the fuel cell stack 2 and the housing 6. extended.
The housing 6 of the reformer/heater 4b is connected to the fuel cell stack 2 by these four passages (the fuel supply passage 12, the fuel discharge passage 14, the oxidant gas supply passage 16, and the oxidant gas discharge passage). 18) is connected and supported only by

The fuel supply passage 12 and the fuel discharge passage 14 are arranged side by side in the vicinity of one short side of the top end plate 10a and extend linearly vertically upward.
The fuel gas reformed in the reformer/heater 4b is supplied to the fuel cell stack 2 through the fuel supply passage 12, and passes through the fuel gas supply passage (not shown) in the fuel cell stack 2. It is distributed to each fuel cell 2a.
Residual fuel gas not used for power generation in each fuel cell 2a was collected through a fuel gas discharge passage (not shown) in the fuel cell stack 2 and attached to the top end plate 10a. The fuel is discharged through the fuel discharge passage 14 to the reformer/heater 4b.

As shown in FIGS. 3 and 4, the oxidizing gas supply passage 16 and the oxidizing gas discharge passage 18 are arranged side by side near one long side of the top end plate 10a, extend vertically upward, and then extend inward. It bends 90 degrees toward and extends horizontally, and further bends 90 degrees and extends vertically upward.
The upper ends of the oxidizing gas supply passage 16 and the oxidizing gas discharge passage 18 are connected to the bottom surface of the housing 6 of the reformer/heater 4b so as to be aligned along the longitudinal central axis thereof.

The air heated in the reformer/heater 4b is supplied to the fuel cell stack 2 through the oxidizing gas supply passage 16, and passes through the oxidizing gas supply passage (not shown) in the fuel cell stack 2. is distributed to each fuel cell 2a.
Residual air not used for power generation in each fuel cell 2a was collected through an oxidant gas discharge passage (not shown) in the fuel cell stack 2 and attached to the top end plate 10a. The oxidant gas is discharged to the reformer/heater 4b through the oxidant gas discharge passage 18. As shown in FIG.

Further, as described above, the position where the oxidant gas supply passage 16 and the oxidant gas discharge passage 18 are connected to the bottom surface of the housing 6 and the position where these passages are connected to the fuel cell stack 2 are shown in top view. differ in However, by curving those passages in the space between the housing 6 and the fuel cell stack 2, the fuel cell stack 2 side and the housing 6 side can be connected.
Therefore, various fuel cell stacks 2 can be connected to a single housing 6 (fluid supply device 4) by appropriately changing the connecting passages.
In addition, since each passage extends into the space sandwiched between the housing 6 and the fuel cell stack 2, the fuel supply passage 12, the fuel discharge passage 14, and the oxidant gas supply can be realized without increasing the occupied floor space. A passageway 16 and an oxidizing gas discharge passageway 18 can be provided.

Furthermore, the fuel supply passage 12, the fuel discharge passage 14, the oxidizing gas supply passage 16, and the oxidizing gas discharge passage 18 each have a connecting structure using a piping screw. Therefore, it is configured to be separable by loosening the connecting nut. Thus, the fuel supply passage 12, the fuel discharge passage 14, the oxidant gas supply passage 16, and the oxidant gas discharge passage 18 are detachably connected to the housing 6 of the reformer/heater 4b.
Alternatively, some or all of these four passages may be configured to extend from the bottom surface of housing 6 and these passages may be detachably connected to fuel cell stack 2 .

<Configuration of evaporator>
Next, the structure of the evaporator 4a will be described with reference to FIGS. 2 and 3. FIG. As shown in FIG. 2, the evaporator 4a includes a water supply pipe 20 for supplying water, a raw fuel gas supply pipe 22 for supplying raw fuel gas, and an exhaust gas for discharging exhaust gas. A discharge pipe 24 is connected.
Further, the housing 6 of the reformer/heater 4b and the evaporator 4a outside thereof are connected by a pipe. As a result, this pipe has a double-pipe structure of an exhaust gas pipe 26 that supplies exhaust gas from the reformer/heater 4b to the evaporator 4a and a mixed gas pipe 28 that is arranged inside (Fig. 3).
The mixed gas conduit 28 is configured to introduce into the reformer/heater 4b a mixture of the steam generated in the evaporator 4a and the raw fuel gas supplied to the evaporator 4a.
An electric heater 29 for auxiliary heating of the evaporator 4a is wound around three sides around the evaporator 4a.

As shown in FIG. 3, the evaporator 4a is formed of a metal plate in the shape of a rectangular parallelepiped box, and has therein an evaporating chamber 30a, a mixing chamber 30b, and an exhaust gas chamber 30c.
The evaporation chamber 30a is a thin space formed directly below the ceiling surface of the evaporator 4a, and the water is supplied from the water supply pipe 20 and the raw fuel gas supply pipe 22 connected to the ceiling surface of the evaporator 4a. Water and raw fuel gas are configured to flow into the evaporation chamber 30a.

The mixing chamber 30b is formed as a space that communicates with the downstream side of the evaporation chamber 30a via a narrow passage 30d.
The steam generated in the evaporation chamber 30a and the raw fuel gas supplied into the evaporation chamber 30a flow through the thin passage 30d into the mixing chamber 30b and are mixed.
A mixed gas conduit 28 is connected to the bottom surface of the mixing chamber 30b. As a result, the steam and raw fuel gas mixed in the mixing chamber 30b are introduced into the reformer/heater 4b through the mixed gas conduit 28. As shown in FIG.

The exhaust gas chamber 30c is a space provided under the evaporator 4a, and is configured such that the exhaust gas flows through the exhaust gas pipe 26 connected to the bottom surface of the evaporator 4a.
The exhaust gas that has flowed into the exhaust gas chamber 30c heats the floor surface of the evaporation chamber 30a provided above the exhaust gas chamber 30c and is discharged from the exhaust gas discharge pipe 24 connected to the side end of the evaporator 4a. It is designed to be
The water supplied to the evaporation chamber 30a is evaporated by heating the floor surface of the evaporation chamber 30a by the exhaust gas flowing in the exhaust gas chamber 30c.

The downstream side of the exhaust gas chamber 30c is made thin so that the inflowing exhaust gas flows along the floor surface of the evaporation chamber 30a (the ceiling surface of the exhaust gas chamber 30c).
Heat transfer fins 30e are arranged in this thin space so that the heat of the exhaust gas flowing through the exhaust gas chamber 30c is efficiently transferred to the floor surface of the evaporation chamber 30a. In this way, the exhaust gas flowing from the exhaust gas pipe 26 connected to one end of the exhaust gas chamber 30c flows toward the exhaust gas discharge pipe 24 connected to the other end (from left to right in FIG. 3). It has become. On the other hand, the water supplied from the water supply pipe 20 connected to the end of the evaporation chamber 30a on the side of the exhaust gas discharge pipe 24 is evaporated in the evaporation chamber 30a toward the other end (Fig. 3 from right to left). In this manner, since the water vapor and the exhaust gas flowing in the evaporator 4a flow in opposite directions, counter-flow type heat exchange is performed between them, and heat exchange is efficiently performed.

<Structure of reformer/heater>
Next, the structure of the reformer/heater 4b will be described with reference to FIGS. 2 to 6. FIG.
As shown in FIG. 2, the reformer/heater 4b is formed in a rectangular parallelepiped box shape surrounded by a metal housing 6, and air, which is an oxidizing gas for power generation, is supplied to the upper surface of the reformer/heater 4b. An air supply pipe 32 is connected for As described above, the upper surface of the housing 6 has a double pipe of the exhaust gas pipe 26 and the mixed gas pipe 28 (FIG. 3), and the bottom has the fuel supply passage 12, the fuel discharge passage 14, and the oxidant gas supply passage. 16, and an oxidant gas discharge passage 18 are connected. A ceramic heater 34 for ignition is attached to one side surface of the housing 6 .

The reformer/heater 4b steam-reforms the mixed gas introduced from the mixed gas conduit 28 to generate a fuel gas, supplies the fuel gas to the fuel cell stack 2 through the fuel supply passage 12, and supplies the fuel gas to the air supply pipe. The air introduced through 32 is heated and supplied to the fuel cell stack 2 through the oxidant gas supply passage 16 .
In addition, the residual fuel gas and residual air (residual oxidant gas) that have not been used for power generation in the fuel cell stack 2 are reformed and heated through the fuel discharge passage 14 and the oxidant gas discharge passage 18, respectively. It is designed to be discharged to the vessel 4b.
The residual fuel gas and residual air discharged through the fuel discharge passage 14 and the oxygen-containing gas discharge passage 18 are combusted in the reformer/heater 4b, and the combustion heat converts the air introduced from the air supply pipe 32 into is designed to heat the Combustion gas generated by combustion is introduced into the evaporator 4a as exhaust gas via an exhaust gas pipe 26. As shown in FIG.

Next, the internal structure of the reformer/heater 4b will be described with reference to FIGS. 3 to 6. FIG.
As shown in FIG. 3, inside the housing 6 that forms the reformer/heater 4b, a closed space that accommodates the reformer 36 and the combustor 38 is formed.

The reformer 36 is a metal annular container having a rectangular cross section when viewed from the top and a rectangular opening in the center. It is connected.
The other end of the reformer 36 is connected to the fuel supply passage 12 (FIG. 5) through which the reformed fuel gas flows out.
The mixed gas conduit 28 extending from the evaporator 4a into the housing 6 is bent 90 degrees in the housing 6, extends horizontally, and then bends vertically downward by 90 degrees to reach the ceiling surface of the reformer 36. It is connected.
The fuel supply passage 12 is connected to the bottom surface of the reformer 36 at the end opposite to the mixed gas conduit 28, extends vertically downward through the bottom surface of the housing 6, and is connected to the fuel cell stack 2. ing.
The reformer 36 is filled with a reforming catalyst 36a. The mixed gas of raw fuel gas and steam flowing from the mixed gas conduit 28 is steam-reformed by coming into contact with the reforming catalyst 36a to generate fuel gas rich in hydrogen gas. The fuel gas steam-reformed in the reformer 36 flows into the fuel supply passage 12 and is supplied to the fuel cell stack 2 .

The combustor 38 is provided inside the bottom wall surface of the housing 6 adjacent to the fuel cell stack 2 . As a result, the residual fuel gas discharged through the fuel discharge passage 14 is combusted by the residual air discharged through the oxygen-containing gas discharge passage 18 .

As shown in FIG. 6, the combustor 38 has a residual fuel gas manifold 38a, a residual fuel gas distribution pipe 38b connected thereto, and a residual air distribution plate 38c for distributing the residual air within the housing 6. .
The residual fuel gas manifold 38a is a box-shaped member attached to the bottom wall surface of one end of the housing 6 so that the residual fuel gas from the fuel discharge passage 14 connected to the bottom wall surface of the housing 6 flows into the interior. is configured to

Residual fuel gas distribution pipe 38b consists of a pipe of circular cross-section. Four of these pipes extend parallel to the longitudinal direction of the housing 6 from the residual fuel gas manifold 38a and are joined at the other end of the housing 6 by a pipe extending in the lateral direction.
A large number of pores are provided on the upper surface of the pipe that constitutes the residual fuel gas distribution pipe 38b. As a result, the residual fuel gas that has flowed from the residual fuel gas manifold 38a into the residual fuel gas distribution pipe 38b is ejected from these pores.

The residual air distribution plate 38c is composed of an elongated metal plate bent to have a trapezoidal cross section (see FIG. 4), and is attached to the center of the bottom wall surface of the housing 6 so as to extend in the longitudinal direction.
The oxygen-containing gas discharge passage 18 connected to the bottom wall surface of the housing 6 communicates with the trapezoidal cross-sectional space surrounded by the residual air dispersion plate 38 c and the bottom wall surface of the housing 6 .
In addition, a large number of pores are formed on the slopes on both sides of the residual air distribution plate 38c, and the residual air that has flowed in from the oxidizing gas discharge passage 18 is injected into the housing 6 through these pores and dispersed. It is designed to be

As shown in FIGS. 3 and 6, a ceramic heater 34 is attached to the side wall of the housing 6, and its tip extends to the center of the confluence of the residual fuel gas distribution pipe 38b.
When the fuel cell module 1 is started, the residual fuel gas is blown out from the pores of the residual fuel gas distribution pipe 38b, and the residual air is blown out from the pores of the residual air distribution plate 38c. By energizing, it is possible to ignite the ejected residual fuel gas. Thereby, the reformer 36 arranged above the combustor 38 within the housing 6 can be heated.
It should be noted that, at the initial stage of startup of the fuel cell module 1, the temperature of the reformer 36 is not raised, so no reforming reaction occurs in the reformer 36, and power generation by the fuel cell stack 2 is not performed. .

<Configuration of oxidant gas heat exchanger>
Next, the oxidant gas heat exchanger provided in the reformer/heater 4b will be described with reference to FIGS. 3 and 4. FIG.
As shown in FIGS. 3 and 4, a portion of the wall surface of the housing 6 has a double wall structure, and the combustor 38 is generated by flowing air for power generation inside the double wall. The heated combustion gas heats the air flowing inside.
That is, a portion of the upper surface, a portion of the longitudinal side wall surface, and a portion of the bottom wall surface of the housing 6 are formed of two metal plates, an inner wall plate 6a and an outer wall plate 6b. Heat transfer fins 40 are arranged between the inner wall plate 6a and the outer wall plate 6b so that the heat of the inner wall plate 6a is efficiently transferred to the space between the inner wall plate 6a and the outer wall plate 6b. there is
Therefore, the inner wall plate 6a, the outer wall plate 6b, and the heat transfer fins 40 heat the supplied air, which is the oxidant gas, by the combustion gas generated by the combustor 38, and supply the air to the fuel cell stack 2. It functions as an oxidant gas heat exchanger.

The air supplied from the air supply pipe 32 flows into the space between the inner wall plate 6a and the outer wall plate 6b that constitute the upper wall surface of the housing 6 (see FIG. 3), and spreads in the lateral direction of the housing 6 from there. , flows into the space between the inner wall plate 6a and the outer wall plate 6b, which form the side walls of the housing 6 (see FIG. 4).
The air that has flowed into the side wall surface of the housing 6 descends downward and flows into the space between the inner wall plate 6a and the outer wall plate 6b that form the bottom wall surface of the housing 6. As shown in FIG.
The air that has flowed into the bottom wall surface of the housing 6 is supplied to the fuel cell stack 2 through an oxidant gas supply passage 16 (FIG. 3) connected to the center of the bottom wall surface of the housing 6 in the width direction. It has become.
Therefore, part of the upper wall surface, the side wall surface, and the bottom wall surface of the housing 6 function as oxidant gas heat exchangers, and the oxidant gas heat exchangers are provided on these wall surfaces.

<Action of fuel cell module>
Next, the operation of the fuel cell module 1 according to the first embodiment of the invention will be described.
First, when the fuel cell module 1 is started, raw fuel gas is supplied to the evaporator 4a of the fluid supply device 4 through the raw fuel gas supply pipe 22, and air for power generation is supplied through the air supply pipe 32. is supplied to the reformer/heater 4 b of the fluid supply device 4 .
As shown in FIG. 3, the supplied raw fuel gas passes through the evaporation chamber 30a and the mixing chamber 30b of the evaporator 4a and flows into the mixed gas conduit 28, and then into the reformer 36 of the reformer/heater 4b. flow into.
In addition, since the temperature of the reformer 36 is low at the initial stage of startup of the fuel cell module 1, the reaction for reforming the raw fuel gas does not occur. The raw fuel gas that has flowed into the reformer 36 flows into the fuel cell stack 2 through the fuel supply passage 12 (see FIG. 5).

On the other hand, the air supplied to the reformer/heater 4b through the air supply pipe 32 passes through the space between the inner wall plate 6a and the outer wall plate 6b of the housing 6 and the oxidant gas supply passage 16 (FIG. 5). and flows into the fuel cell stack 2.
The raw fuel gas and air that have flowed into the fuel cell stack 2 pass through internal passages and are discharged to the reformer/heater 4b via the fuel discharge passage 14 and the oxidant gas discharge passage 18, respectively.
It should be noted that, at the initial stage of startup of the fuel cell module 1, the temperature of the fuel cell stack 2 is low, so that the power generation reaction does not occur in the fuel cell stack 2. FIG.

The raw fuel gas that has flowed into the reformer/heater 4b through the fuel discharge passage 14 passes through the residual fuel gas manifold 38a of the combustor 38, flows into the residual fuel gas distribution pipe 38b, and is ejected from the pores.
On the other hand, the air discharged to the reformer/heater 4b through the oxidant gas discharge passage 18 flows into the residual air distribution plate 38c and is jetted out from the pores.
When the fuel cell module 1 is started, the ceramic heater 34 is energized, and the heat of the ceramic heater 34 ignites the raw fuel gas ejected from the pores of the residual fuel gas distribution pipe 38b. This causes combustor 38 to generate combustion heat.

When the combustor 38 is ignited, the reformer 36 arranged above it is heated, and the temperature of the reforming catalyst 36a inside rises.
In addition, the combustion gas generated by the combustion heats the oxidizing gas heat exchanger constituted by the inner wall plate 6a and the outer wall plate 6b of the housing 6, thereby heating the air flowing inside.
Since the heated air flows into the fuel cell stack 2 , the heat heats the fuel cell stack 2 .
Here, since the housing 6 of the fluid supply device 4 is surrounded by the heat insulating material 8, the fuel cell stack 2 is hardly heated by radiant heat or the like from the housing 6, and the fuel cell stack 2 is substantially It is heated only by the fluid (air and fuel gas) supplied from the fluid supply device 4 .

Combustion gas generated in the housing 6 flows through the exhaust gas pipe 26 into the evaporator 4a as exhaust gas.
The exhaust gas that has flowed into the evaporator 4a is discharged from the exhaust gas discharge pipe 24 through the exhaust gas chamber 30c.
At this time, the evaporation chamber 30a provided above the exhaust gas chamber 30c is heated.
Thus, the water supplied to the evaporator 4 a is heated by the combustion gases produced by the combustor 38 and supplied by the exhaust gas line 26 .
After the temperature of the evaporation chamber 30a rises, the supply of water from the water supply pipe 20 is started, and steam is generated in the evaporation chamber 30a.
Incidentally, when the fuel cell module 1 is activated, the electric heater 29 may be energized in order to assist the heating of the evaporation chamber 30a.

When steam is generated in the evaporation chamber 30 a , a mixed gas of raw fuel gas and steam is supplied to the reformer 36 .
When the temperature of the reformer 36 rises sufficiently, the steam reforming reaction is induced by the reforming catalyst 36a, and fuel gas rich in hydrogen gas is produced from the raw fuel gas.
The generated fuel gas is supplied to the fuel cell stack 2 . When the temperature of the fuel cell stack 2 rises sufficiently, the fuel gas and the air heated in the reformer/heater 4b generate power generation reaction. In a state where the temperature of the fuel cell stack 2 has risen to a temperature at which power generation is possible, power is extracted from the fuel cell stack 2 via the bus bar B1 to start power generation.

<Effects of the fuel cell module of the first embodiment of the present invention>
According to the fuel cell module 1 of the first embodiment of the present invention, first, an outer container member is provided to accommodate the stacked fuel cell stack 2 configured by stacking a plurality of flat plate fuel cells 2a. Not done. As a result, the base end sides of the bus bars B1 and B2 are positioned at the upper end portion of the fuel cell stack 2 (more specifically, between the upper end surface of the uppermost fuel cell 2a and the bottom surface of the top end plate 10a), And, it can be easily provided at each of the lower end portions of the fuel cell stack 2 (more specifically, between the lower end surface of the lowest fuel cell 2a and the upper surface of the bottom end plate 10b).
Further, when the fuel cell stack 2 is accommodated in the outer shell member, the structure that takes into account design errors and thermal expansion differences between the two can be omitted by eliminating the need for the outer shell member.
Furthermore, since the front ends of the busbars B1 and B2 can protrude from the outside of the fuel cell module 1 without penetrating the outer shell member, the outer shell member and the busbars B1 and B2 are connected to each other. It is also possible to omit the structure and parts that electrically insulate between.
As a result, by suppressing the number of parts, it is possible to suppress the manufacturing cost, the product weight, and the product size, and also to suppress the electrical resistance.

Further, according to the fuel cell module 1 of the present embodiment, the heat insulating material 8 can reduce heat directly transmitted between the fuel cell stack 2 and the housing 6 . As a result, it is possible to further reduce the influence of changes in the arrangement of the reformer 36 and the combustor 38 in the housing 6 on the temperature distribution of the fuel cell stack 2 .
In addition, the heat insulating material 8 can directly or indirectly constrain the base end sides of the bus bars B1 and B2 provided at the upper end portion and the lower end portion of the fuel cell stack 2, respectively. B2 can be stably held without penetrating the outer shell member.

Furthermore, according to the fuel cell module 1 of the present embodiment, the base ends of the bus bars B1 and B2 are fixed to the upper end and the lower end of the fuel cell stack 2, respectively, directly or indirectly by the heat insulating material 8. Since the fixed ends are physically restrained, the heat transfer between the fixed ends of the bus bars B1 and B2 and their peripheral portions can be suppressed by the heat insulating material 8 .
In addition, since the heat insulating material 8 is a non-conductive insulator, it is possible to electrically insulate between the fixed end portions of the bus bars B1 and B2 and their peripheral portions.
Furthermore, in addition to the fact that an outer shell member for housing the fuel cell stack 2 is not provided, the tips of the bus bars B1 and B2 protrude to the outside of the heat insulating material 8, so that the heat insulating material directly It becomes a free end that is neither constrained nor indirectly constrained. As a result, the positions of the free ends of the busbars B1 and B2 can be changed according to the positions of the fixed ends of the busbars B1 and B2 fixed to the upper and lower ends of the fuel cell stack 2, respectively. Therefore, the degree of freedom in design can be increased.
Therefore, when the power generated in the fuel cell 2a is directly taken out of the fuel cell module 1 by the bus bars B1 and B2, the power is taken out according to the positions of the free ends of the bus bars B1 and B2. The position and direction can be freely set.

Further, according to the fuel cell module 1 of the present embodiment, in a state in which the wires from the harness (not shown) are connected to the wire connection portions (terminal holes C1, C2) at the free ends of the bus bars B1, B2, , the heat insulating material 8 can function as a cushioning material for suppressing deformation of the busbars B1 and B2.
That is, a deformation load or the like (bending load or deflection load) acts on the free ends of the busbars B1 and B2 due to the weight of the wires and harnesses (not shown), and the busbars B1 and B2 themselves are slightly deformed. Even if (bending deformation, deflection deformation, or the like) occurs, the heat insulating material 8 acts as a cushioning material that suppresses deformation of the busbars, so that the busbars B1 and B2 can be protected from damage.

Furthermore, according to the fuel cell module 1 of the present embodiment, the surfaces (upper surfaces S1, S3 ) and back surfaces (lower surfaces S2, S4) are parallel to each other, the outer surface of the outermost flat plate-type fuel cell in the fuel cell stack 2 (the upper surface of the uppermost fuel cell 2a (uppermost end surface E1) and the bottom surface (lowermost end surface E2) of the lowermost fuel cell 2a.
As a result, the busbars B1 and B2 can be easily assembled to the upper and lower ends of the fuel cell stack 2, and the structure can be simplified.

Further, according to the fuel cell module 1 of the present embodiment, the cover member A1 is provided outside the heat insulating material 8, and the cover member A1 can hold the heat insulating material 8 securely.
Therefore, the heat insulating material 8 held by the cover member A1 can reliably protect the bus bars B1, B2 and the fuel cell stack 2 from damage.

Next, a fuel cell module according to a second embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG.
FIG. 7 is a schematic front view of the entire fuel cell module according to the second embodiment of the present invention, with the heat insulating material and the end plate on the front side removed. 8 is an enlarged perspective view of a busbar portion in the fuel cell module according to the second embodiment of the present invention shown in FIG. 7. FIG.
Here, in the fuel cell module according to the second embodiment of the invention shown in FIGS. 7 and 8, the same parts as those of the fuel cell module 1 according to the first embodiment of the invention described above are denoted by the same reference numerals. is omitted.

First, as shown in FIGS. 7 and 8, in the stacked fuel cell stack 102 of the fuel cell module 100 according to the second embodiment of the present invention, the stacking surface Ln of the plurality of flat plate fuel cells 2a is The stacked fuel cell stack 2 of the fuel cell module 1 according to the first embodiment of the present invention described above is characterized in that the fuel cells 2a are stacked in the horizontal front-rear direction so as to form a vertical plane. is different from the stacking direction of the fuel cells 2a stacked in the vertical direction.
Further, as shown in FIGS. 7 and 8, in the fuel cell module 100 of the present embodiment, two bus bars B101 and B102 are formed in the shape of a long plate. This is different from the fuel cell module 1 according to the first embodiment of the present invention described above.
That is, the busbars B101 and B102 are arranged such that their front surfaces (front surfaces S101 and S103) and rear surfaces (rear surfaces S102 and S104) are vertical surfaces, and are parallel to the stacking surface Ln of each fuel cell 2a. ing.
Further, the distal end portions of the bus bars B101 and B102 are arranged in a horizontal direction (more specifically, each shown in FIGS. The busbars B101 and B102 protrude to the right when viewed from the front side.
However, as a modification of the fuel cell module 100 of the present embodiment, for example, when a lower space can be secured in an installation state other than the floor placement, the front surfaces (front surfaces S101 and S103) and the rear surfaces (front surfaces S101 and S103) of the bus bars B101 and B102 can be arranged. The rear surfaces S102, S104) may be arranged so that the front end portions of the bus bars B101, B102 protrude outward in the vertical direction (downward).

<Effects of the fuel cell module of the second embodiment of the present invention>
If the front and back surfaces of the busbar are arranged so as to be horizontal, wires from a harness (not shown) are connected to the wire connection portions (terminal holes C1 and C2) at the free ends of the busbar. In this state, a downward deformation load (bending load, bending load, etc.) acts on the free end of each busbar due to the weight of the electric wire or the like, so that the busbar itself is likely to be deformed.
On the other hand, in the fuel cell module 100 of the present embodiment, when the electric wires are connected to the electric wire connection portions (terminal holes C1 and C2) at the free ends of the bus bars B101 and B102, the dead weight of the electric wires and the like cause Even if a downward deformation load (bending load, deflection load, etc.) is applied to the free ends of the busbars B101 and B102, the front surfaces (front surfaces S101 and S103) and the rear surfaces (rear surfaces S102 and S104) of the busbars B101 and B102 It can be placed in a vertical plane.
As a result, compared to the case where the front and back surfaces of the busbars B101 and B102 are arranged in a horizontal plane, downward deformation load (bending load, deflection load, etc.) due to electric wires or the like from a harness (not shown) can be applied. It is possible to increase the rigidity (bending rigidity, deflection rigidity, etc.) of each bus bar B101, B102.
Therefore, in a state where wires from a harness (not shown) are connected to the wire connecting portions (terminal holes C1 and C2) at the free ends of the bus bars B101 and B102, the bus bars B101 and B102 are deformed (bending deformation, bending deformation, etc.), it is possible to reduce the risk of damage to the bus bars B101, B102 and the fuel cell stack 102 due to excessive deformation.

Further, according to the fuel cell module 100 of the present embodiment, each of the plurality of flat plate-type fuel cells 2a is horizontally stacked so that the stacking surface Ln thereof becomes a vertical surface. By simply assembling the front surface (front surface S101, S103) or the rear surface (rear surface S102, S104) of each bus bar B101, B102 to the outer surface (front surface and rear surface) of the flat plate type fuel cell 2a, these can be mounted in a vertical plane. can be placed.
Therefore, the busbars B101 and B102 can be easily assembled to the front and rear ends of the fuel cell stack 2, respectively. Further, by rotating and positioning the busbars B101 and B102 in the vertical plane, it is possible to freely set the position and direction of power extraction from the busbars B101 and B102.

Although the fuel cell modules 1 and 100 of the first and second embodiments of the present invention have been described above, various modifications can be made to the first and second embodiments described above. In particular, in the fuel cell modules 1 and 100 of the first and second embodiments described above, the reformer and the combustor are accommodated in the housing, and the evaporator is arranged outside the housing. The present invention can also be configured to be contained within a housing.
Furthermore, the present invention can be constructed such that a desulfurizer for removing sulfur components contained in the raw fuel gas and a combustion catalyst for removing carbon monoxide and the like in the exhaust gas are accommodated in the housing.
In addition, in the fuel cell modules 1 and 100 of the first and second embodiments described above, the oxidant gas heat exchanger is integrally formed with the outer wall surface of the housing. The invention can also be configured to be housed internally.
Furthermore, in the fuel cell modules 1 and 100 of the first and second embodiments described above, the housings are arranged side by side above the fuel cell stack. Alternatively, the housings can be arranged side by side on the side of the fuel cell stack.

REFERENCE SIGNS LIST 1 fuel cell module according to the first embodiment of the present invention 2 fuel cell stack 2a fuel cell 4 fluid supply device 4a evaporator 4b reformer/heater 6 housing 6a inner wall plate 6b outer wall plate 8 heat insulating material 10a top end plate 10b Bottom end plate 12 fuel supply passage 14 fuel discharge passage 16 oxidant gas supply passage 18 oxidant gas discharge passage 20 water supply pipe 22 raw fuel gas supply pipe 24 exhaust gas discharge pipe 26 exhaust gas pipe 28 mixed gas pipe 29 electric heater 30a evaporation chamber 30b mixing chamber 30c exhaust gas chamber 30d passage 30e fins 32 air supply pipe 34 ceramic heater 36 reformer 36a reforming catalyst 38 combustor 38a residual fuel gas manifold 38b residual fuel gas distribution pipe 38c residual air distribution plate 40 fins 100 fuel cell module according to the second embodiment of the present invention A1 cover member B1 upper bus bar (bus bar)
B2 lower busbar (busbar)
B101 Front bus bar B102 Rear bus bar C1 Terminal hole (wire connection part)
C2 terminal hole (wire connection part)
E1 Uppermost surface of fuel cell E2 Lowermost surface of fuel cell Ln Layered surface of fuel cell S1 Upper surface of upper bus bar (surface of bus bar)
S2 Lower surface of upper busbar (back surface of busbar)
S3 Upper surface of lower busbar (surface of busbar)
S4 Lower surface of lower busbar (back surface of busbar)
S101 Front side of front busbar (surface of busbar)
S102 Rear surface of front busbar (back surface of busbar)
S103 Front side of rear busbar (surface of busbar)
S104 Rear surface of rear busbar (back surface of busbar)

Claims (9)

A fuel cell module that generates power by reacting supplied fuel gas and oxidant gas,
a closed fuel cell stack in which flow paths for fuel gas and oxidant gas are respectively defined;
a reformer that reforms the raw fuel gas to generate a fuel gas containing hydrogen and supplies the hydrogen-containing fuel gas to the fuel cell stack;
a combustor that burns residual fuel gas remaining in the fuel cell stack without being used for power generation to heat the reformer;
an outer container member having a space for housing the reformer and the combustor formed therein;
a conductive bus bar for extracting power generated in the fuel cell that is part of the fuel cell stack ,
The outer container member does not accommodate the fuel cell stack,
The base end of the bus bar is provided in the fuel cell stack, and the front end of the bus bar protrudes directly to the outside of the fuel cell module without penetrating through the outer container member. and fuel cell module. further comprising a heat insulating material arranged to thermally isolate the fuel cell stack from the outer shell member ;
2. The fuel cell module according to claim 1, wherein the base end of the bus bar is restrained by the heat insulating material. 3. The fuel cell module according to claim 2, wherein said fuel cell stack is surrounded by said heat insulating material. The heat insulating material is a non-conductive insulator, and the base end of the bus bar is a fixed end covered with the heat insulating material and fixed to the end of the fuel cell stack. 4. The fuel cell module according to claim 2, wherein the tip protrudes to the outside of the heat insulating material and is a free end that is not restrained by the heat insulating material. The free end portion of the bus bar includes a wire connection portion to which a wire is connected, and the heat insulating material is a cushioning material that suppresses deformation of the bus bar while the wire is connected to the wire connection portion. 5. The fuel cell module according to claim 2. The bus bar is arranged in the fuel cell stack such that the front surface or the back surface thereof is parallel to the stacking surface on which the plurality of flat fuel cells of the closed fuel cell stack are stacked. 6. The fuel cell module according to any one of claims 1 to 5, which is disposed on the outer surface of the outermost flat plate type fuel cell. 7. The fuel cell module according to claim 6, wherein the bus bar is formed in a plate-like shape from its base end to its longitudinal tip, and is arranged such that its front surface or rear surface is a vertical plane. 7. The fuel cell module according to claim 6, wherein each of said plurality of flat plate-type fuel cells are stacked horizontally so that their stacking surfaces are vertical surfaces. 6. The fuel cell module according to any one of claims 2 to 5, further comprising a cover member provided outside said heat insulating material, said cover member being configured to hold said heat insulating material. .

Images