WO2020129372A1 - Fuel cell module - Google Patents

Abstract

The fuel cell module (1) according to the present invention has: a sealed fuel cell stack (2) formed by stacking a plurality of flat-plate fuel cells (2a) on one another; a reformer (36); a combustor (38); and conductive bus bars (B1, B2) for extracting electric power generated in the fuel cells, wherein the fuel cell module has no outer vessel member provided thereto for accommodating the fuel cell stack, and the bus bars each have the base end side thereof disposed at an end of the fuel cell stack while the distal end side thereof is configured to protrude, without penetrating an outer vessel member, so as to enable direct extraction outside the fuel cell module.

Description

Fuel cell module

The present invention relates to a fuel cell module, and more particularly to a fuel cell module that generates electricity by reacting a supplied fuel gas with an oxidant gas.

BACKGROUND ART Conventionally, as a fuel cell module that generates electric power by reacting a supplied fuel gas with an 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, and these are housed in a housing.
Further, in the above-described conventional fuel cell module, the fuel cell cell stack is a stacked fuel cell cell stack in which a plurality of fuel cell cells are laminated, and each fuel cell cell is composed of an oxide ion conductor. It is configured by providing a cathode electrode and an anode electrode on both surfaces of the formed flat plate-shaped electrolyte, respectively. Further, a cathode separator and an anode separator are arranged between the fuel cells, respectively. Further, the cathode separator is provided with an oxidant gas flow passage for supplying an oxidant gas to the cathode electrode, and the anode separator is provided with a fuel gas flow passage for supplying a fuel gas to the anode electrode.

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

Residual fuel gas flowing out from the fuel gas outlet and residual oxidant gas flowing out from the oxidant gas outlet are guided to a combustor arranged in the housing and burned there. The combustion heat generated in the combustor exchanges heat with the oxidant gas flowing in the oxidant gas passages arranged on both side surfaces of the casing. The oxidant gas whose temperature has been raised by heat exchange is introduced into the fuel cell stack through the oxidant gas inlet. As a result, the temperature of the fuel cell stack is raised to a temperature at which the power generation reaction is possible. As described above, in the fuel cell module described in Patent Document 1, in the combustor arranged in the housing, the residual fuel gas is burned by the residual oxidant gas, and the fuel cell stack is formed by the generated combustion gas. The fuel cell stack is indirectly heated to efficiently raise the temperature of the fuel cell stack to a temperature at which the power generation reaction is possible, and the temperature is maintained.

In addition, in the above-described conventional fuel cell module, it is general that a stacked fuel cell stack is housed inside an outer container member such as a housing, and electric power generated in the fuel cell is taken out. The conductive bus bar penetrates the outer container member and is taken out to the outside.

JP, 2017-50192, A

However, in the conventional fuel cell module described in Patent Document 1 described above, the outer container member that accommodates the fuel cell stack is provided, and the bus bar penetrates the outer container member. A structure that electrically insulates between the outer container member and the outer container member is required.
Further, in order to house the fuel cell stack in the outer container member, a structure that takes into account design error and thermal expansion difference between the two is required.
Therefore, in order to secure these necessary structures, there are problems that the number of parts increases, the processing cost and the like increase, and the size and weight increase, so that the manufacturing cost increases.
Further, if the number of parts is increased, there is a problem that the electric resistance may be increased accordingly.

Therefore, the present invention has been made in order to solve the above-mentioned problems of the prior art, and an object thereof is to provide a fuel cell module capable of suppressing the manufacturing cost and suppressing the electric resistance. I am trying.

In order to solve the above-mentioned problems, the present invention is a fuel cell module that generates electricity by reacting a supplied fuel gas with an oxidant gas, and the flow paths of the fuel gas and the oxidant gas are defined respectively. A closed fuel cell stack, a reformer that reforms raw fuel gas to generate fuel gas containing hydrogen, and supplies the fuel gas to the fuel cell stack, and a reformer used for power generation in the fuel cell stack. The combustor that burns the residual fuel gas remaining without heating to heat the reformer, and a conductive bus bar that takes out the electric power generated in the fuel cell, the fuel cell module, The outer peripheral container member for accommodating the fuel cell stack is not provided, and the bus bar has the base end side thereof provided in the fuel cell stack and the front end side of the fuel cell without penetrating the outer container member. It is characterized in that it protrudes directly to the outside of the module so that it can be taken out.
In the present invention thus configured, first, since the 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. ..
In addition, a structure in which the fuel cell stack is accommodated in the outer container member in consideration of design error and thermal expansion difference between the two can be omitted by eliminating the outer container member.
Further, since the tip end side of the busbar can be directly and externally protruded outside the fuel cell module without penetrating the outer container member, a structure electrically insulating between the outer container member and the busbar. The parts and parts can also be omitted.
As a result, by suppressing the number of parts, it is possible to suppress the manufacturing cost and also the electric resistance.

In the present invention, preferably, a housing in which a space for accommodating the reformer and the combustor is formed, and heat insulation arranged to thermally isolate the fuel cell stack from the housing. The busbar is constrained at its proximal end side by the heat insulating material.
In the present invention thus configured, 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 the layout change of the reformer and the combustor in the housing on the temperature distribution of the fuel cell stack.
Further, since the heat insulating material can restrain the base end side of the bus bar provided at the end portion of the fuel cell stack, the bus bar can be stably held without penetrating the outer container member.

In the present invention, preferably, the fuel cell stack is surrounded by the heat insulating material.
In the present invention thus configured, it is possible to more effectively reduce the influence of the layout change of the reformer, the combustor and the like 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 portion of the bus bar is covered with the heat insulating material and fixed to the end portion of the fuel cell stack. The end portion of the bus bar is a free end portion that protrudes to the outside of the heat insulating material and is not constrained by the heat insulating material.
In the present invention thus configured, the base end portion of the bus bar is a fixed end portion that is fixed to the end portion of the fuel cell stack and directly or indirectly constrained by the heat insulating material. The heat transfer between the fixed end portion and its peripheral portion can be suppressed by the heat insulating material.
Further, 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.
Further, since the outer container member is not provided and the tip end portion of the bus bar projects to the outside of the heat insulating material, the free end portion is not restricted by the heat insulating material. Thus, the position of the free end portion of the bus bar can be changed according to the position of the fixed end portion of the bus bar fixed to the end portion of the fuel cell stack, so that the degree of freedom in design can be increased.
Therefore, when the electric power generated in the fuel cell unit is directly taken out of the fuel cell module by the bus bar, the position and direction for taking out electric power can be freely set according to the position of the free end of the bus bar. it can.

In the present invention, preferably, the free end portion of the bus bar is provided with an electric wire connecting portion to which an electric wire is connected, and the heat insulating material is a deformation of the bus bar in a state where the electric wire is connected to the electric wire connecting portion. It is a cushioning material that suppresses
In the present invention thus configured, the heat insulating material can function as a cushioning material that suppresses the deformation of the bus bar when the electric wire is connected to the electric wire connecting portion at the free end of the bus bar.
That is, even if a deformation load is applied to the free end portion of the bus bar due to its own weight and elastic force of the electric wire, and the bus bar itself is slightly deformed, the heat insulating material serves as a cushioning material that suppresses the deformation of the bus bar. , It is possible to protect the bus bar and the fuel cell stack from damage.

In the present invention, preferably, the bus bar is such that the front surface or the back surface is parallel to a stacking surface on which each of the plurality of flat plate-type fuel battery cells of the sealed fuel battery cell stack is stacked, It is arranged on the outer surface of the outermost flat type fuel cell of the fuel cell stack.
In the present invention thus configured, in the bus bar, among the fuel cell stacks, the front surface or the back surface is parallel to the stacking surface on which each of the plurality of flat plate type fuel battery cells is stacked. Can be arranged on the outer surface of the outermost flat 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 shape from the base end portion to the tip end portion in the longitudinal direction, and is arranged such that the front surface or the back surface thereof is a vertical plane.
If the bus bar formed in a plate shape from the base end to the distal end in the longitudinal direction is arranged so that the front surface or the back surface is a horizontal surface, the electric wire was connected to the electric wire connection portion of the free end of the bus bar. In this state, a downward deformation load (a bending load, a bending load, etc.) acts on the free end portion of the bus bar due to the weight of the electric wire or the like, so that the bus bar itself is easily deformed.
On the other hand, in the present invention, in the state in which the electric wire is connected to the electric wire connecting portion of the free end portion of the bus bar, downward load (bending load, bending load, etc.) is applied to the free end portion of the bus bar due to its own weight or the like. ) Occurs, the front surface or the back surface of the bus bar can be arranged so as to be vertical.
As a result, the rigidity (bending rigidity, bending rigidity, etc.) of the bus bar with respect to downward deformation load (bending load, bending load, etc.) can be increased compared to the case where the front surface or the back surface of the bus bar is arranged in a horizontal plane.
Therefore, it is possible to suppress the deformation (bending deformation, bending deformation, etc.) of the busbar when the electric wire is connected to the electric wire connecting portion at the free end of the busbar, and thus the risk of damaging the busbar due to excessive deformation is reduced. can do.

In the present invention, preferably, each of the plurality of flat plate type fuel cell units is horizontally stacked such that the stacking surface thereof is a vertical plane.
In the present invention configured as described above, since each of the plurality of flat plate-type fuel cells is stacked in the horizontal direction so that the stacking surface becomes a vertical plane, the outermost flat plate-type fuel By simply assembling the front surface or the back surface of the bus bar to the outer surface of the battery cell, these can be arranged in the vertical plane.
Therefore, the bus bar can be easily attached to the end of the fuel cell stack. Further, by rotating and positioning the bus bar in the vertical plane, it is possible to freely set the position and the direction in which electric power is taken out from the bus bar.

In the present invention, preferably, further, a cover member provided outside the heat insulating material is provided, and the cover member is configured to hold the heat insulating material.
In the present invention thus configured, the heat insulating material can be reliably held by the cover member, so that the bus bar and the fuel cell stack can be surely protected from being damaged.

According to the fuel cell module of the present invention, it is possible to suppress the manufacturing cost and the electric resistance.

FIG. 1 is a schematic configuration diagram of an entire fuel cell module according to a first embodiment of the present invention. FIG. 3 is a perspective view of the fuel cell module according to the first embodiment of the present invention. FIG. 3 is a front sectional view of the fuel cell module according to the first embodiment of the present invention. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a sectional view taken along line VV of FIG. 3. FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 3. FIG. 11 is a schematic front view of the entire fuel cell module according to the second embodiment of the present invention with a heat insulating material and an 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.

Next, the fuel cell module according to the first embodiment of the present invention will 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 a first embodiment of the present invention includes a fuel cell stack 2 that performs a power generation reaction, and a fuel gas obtained by reforming the raw fuel gas in the fuel cell stack 2. And a fluid supply device 4 for supplying air that is a heated oxidant gas.
First, the fuel cell stack 2 is a so-called "stacked fuel cell stack", which is configured by vertically stacking a plurality of flat-plate fuel cell 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 the closed chamber.

Further, the fluid supply device 4 includes a housing 6, and the housing 6 is arranged above the fuel cell stack 2 in the vertical direction. The fuel cell stack 2 and the housing 6 are surrounded by the heat insulating material 8 and also provided between the fuel cell stack 2 and the housing 6.
As a result, 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.
Here, in this specification, a hermetically-sealed container that allows inflow and outflow of air, water, fuel gas, and the like is defined as an “outer shell member”.
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, the outer container member, which is a closed container, is not provided.

Further, the reformer 36 and the combustor 38 are housed in the space sealed by the housing 6.
In addition, in FIG. 1, the heat insulating material 8 is described as one continuous piece, but may be composed of a plurality of heat insulating materials. For example, the heat insulating material that surrounds the fuel cell stack 2 and the housing 6 and the heat insulating material that is provided between the fuel cell stack 2 and the housing 6 may be different heat insulating materials.
Further, as the heat insulating material, a plurality of members having different heat insulating performances may be used in combination, and the superposing and arranging methods can be designed according to the required specifications.
Further, 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 as needed. By arranging it, the effect is achieved.

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 fuel gas rich in hydrogen.
The fuel gas generated in the reformer 36 is sent to the fuel cell stack 2, and is used for power generation in the fuel cell stack 2. The 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.
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 penetrates the heat insulating material 8 and extends to the fuel cell stack 2.

The combustor 38 is configured to burn the residual fuel that remains in the fuel cell stack 2 without being used for power generation.
The fuel not used for power generation in the fuel cell stack 2 is discharged to the housing 6 side through a fuel discharge passage 14 extending between the housing 6 of the fluid supply device 4 and the fuel cell stack 2. Has become. 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 that surrounds the housing 6 of the fluid supply device 4.
The residual fuel discharged to the housing 6 side is combusted by the combustor 38 housed in the housing 6 and heats the reformer 36 arranged above the combustor 38. As a result, the 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 from the outside to the fluid supply device 4. Then, this air is heated by the combustion heat of the combustor 38 and is supplied to the fuel cell stack 2 in a high temperature state.
The fuel cell stack 2 is mainly heated by the heat of the power generation air heated to a high temperature to a temperature at which a power generation reaction is possible.
The power generation air heated in the fluid supply device 4 is supplied to the fuel cell stack 2 through the oxidant gas supply passage 16 extending from the housing 6. This oxidant gas supply passage 16 also extends from the fluid supply device 4 to the fuel cell stack 2 through the heat insulating material 8 surrounding the housing 6 of the fluid supply device 4.

Further, the residual air supplied to the fuel cell stack 2 and not used for power generation and remaining is discharged to the housing 6 side through the oxidant gas discharge passage 18.
The oxidant 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 in the housing 6. The combustion gas generated by the combustion is exhausted from the fluid supply device 4 as exhaust gas.

As described above, in the fuel cell module 1 according to the embodiment of the present invention, the residual fuel gas is burned by the residual air in the combustor 38 of the fluid supply device 4, and the reformer 36 is heated by the combustion heat. It has become.
On the other hand, the reformer 36 and the combustor 38 are housed in 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 not substantially 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 or the like is used. Therefore, the fuel cell stack 2 is not directly heated.
Therefore, the temperature of the fuel cell stack 2 can be substantially regulated only by the flow rate and the temperature of the fluid supplied thereto.

As an apparatus used with the fuel cell module, an evaporator that produces steam for steam reforming, a desulfurizer that removes the sulfur component contained in the raw fuel gas, a combustion that removes carbon monoxide, etc. in the exhaust gas There are a catalyst device and the like, but these may be housed in a housing.
Alternatively, these devices can be placed outside the housing and covered with a heat insulating material so that they are heated by the heat of the exhaust gas discharged from 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.
First, FIG. 2 is a perspective view of the fuel cell module according to the first embodiment of the present invention. Next, FIG. 3 is a front sectional view of the fuel cell module according to the first embodiment of the present invention. FIG. 4 is a sectional view taken along the line IV-IV in FIG. Further, FIG. 5 is a sectional view taken along line VV of FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG.
In FIG. 2, the heat insulating material surrounding the fuel cell stack and the like is omitted.

<Overall structure of fuel cell module>
As shown in FIG. 2, the fuel cell module 1 according to the present embodiment includes a fuel cell stack 2 that performs a power generation reaction, a fuel gas obtained by reforming the fuel cell stack 2 from a raw fuel gas, and a heated oxidizer. A fluid supply device 4 for supplying air that is gas. Further, the fluid supply device 4 is composed of an evaporator 4a and a reforming/heating device 4b. The evaporator 4a is configured to evaporate the supplied water to generate water vapor and mix the water vapor with the raw fuel gas. The reforming/heating device 4b is mixed with the mixture supplied from the evaporator 4a. The gas is steam-reformed to generate a fuel gas containing hydrogen, and the fuel gas is supplied to the fuel cell stack 2.

Further, the reforming/heating device 4b is covered with a substantially rectangular parallelepiped metal housing 6, and the fuel cell stack 2, the housing 6 of the reforming/heating device 4b arranged above the fuel cell stack 2, and the evaporator 4a. Are arranged side by side in the vertical direction. The fuel cell stack 2, the housing 6, and the evaporator 4a are surrounded by the heat insulating material 8, and the fuel cell stack 2 is thermally isolated from the housing 6 and the evaporator 4a.

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

Next, as shown in FIGS. 2 and 3, these busbars B1, B2 are composed of a pair of upper and lower upper busbars B1 and lower busbars B2 in which a conductive member such as metal is formed into a long plate shape.
The base end of the upper bus bar B1 is provided between the upper end surface of the uppermost fuel cell 2a 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 lowermost fuel cell 2a of the fuel cell stack 2 and the upper surface of the bottom end plate 10b.
That is, each of the bus bars B1 and B2 includes the outer surface (the upper surface (uppermost end surface E1) of the uppermost fuel cell 2a) and the lowermost fuel cell of the outermost flat plate-type fuel cell 2a in the fuel cell stack 2. It is arranged on the bottom surface (the lowermost 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, with respect to the stacking surface Ln on which the plurality of flat plate-type fuel battery cells 2a are stacked, the respective surfaces (upper surface S1 , S3) and the back surfaces (lower surfaces S2, S4) are parallel to each other.
Further, the tip end portions of the bus bars B1 and B2 are horizontally (to be more specific, shown in FIGS. 2 and 3) so that they can be directly taken out of the fuel cell module 1 without penetrating the outer container member. The bus bars B1 and B2 are projected to the right side when viewed from the front side).

Next, as shown in FIG. 3, the heat insulating material 8 is a non-conductive insulator, and the bus bars B1 and B2 are surrounded by the heat insulating material 8 from the base end side to the vicinity of the intermediate portion in the longitudinal direction. Have been restrained directly or indirectly.
Thereby, the base end portions of the bus bars B1 and B2 are fixed to the uppermost end portion and the lowermost end portion of the fuel cell 2a of the fuel cell stack 2, respectively, and directly or indirectly by the heat insulating material 8. It has a fixed fixed end.
On the other hand, the tip ends of the bus bars B1 and B2 project to the outside of the heat insulating material 8 and are free end portions that are not restrained by the heat insulating material 8.

Next, as shown in FIGS. 2 and 3, electric wire connection portions (terminal holes C1 and C2) are provided at the tip end portions (free end portions) of the bus bars B1 and B2.
Electric wires from a harness (not shown) in which a plurality of electric wires or cables are bundled are connected to the tip ends (free ends) of the bus bars B1 and B2 including the electric wire connecting portions (terminal holes C1 and C2). Connection terminal.
Further, in a state in which the electric wires are connected to the electric wire connecting portions (terminal holes C1, C2) of the bus bars B1, B2, the self-weight of the harness (not shown) or the like causes the tip portions (free end portions) of the bus bars B1, B2. Although a bending load or a bending load is generated that tries to deform the shaft downward, the heat insulating material 8 functions as a cushioning material that suppresses such deformation (bending deformation or bending deformation) of the bus bars B1 and B2. It is also becoming.

Further, 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.
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 arranged 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 penetrate the heat insulating material 8 arranged between the fuel cell stack 2 and the housing 6. It is extended.
The housing 6 of the reformer/heater 4b has four passages (a fuel supply passage 12, a fuel discharge passage 14, an oxidant gas supply passage 16 and an oxidant gas discharge passage) for the fuel cell stack 2. 18) only connected and supported.

The fuel supply passage 12 and the fuel discharge passage 14 are attached side by side in the vicinity of one short side of the top end plate 10a, and linearly extend 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 adapted to be distributed to each fuel cell 2a.
Residual fuel gas remaining without being used for power generation in each fuel cell 2a is 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 to the reformer/heater 4b through the fuel discharge passage 14.

As shown in FIGS. 3 and 4, the oxidant gas supply passage 16 and the oxidant gas discharge passage 18 are attached side by side in the vicinity of one long side of the top end plate 10a, and extend vertically upward, respectively, and then, inside. It bends 90 degrees toward and extends in the horizontal direction, and further bends 90 degrees and extends vertically upward.
The upper ends of the oxidant gas supply passage 16 and the oxidant gas discharge passage 18 are connected to the bottom surface of the housing 6 of the reforming/heating device 4b side by side on the central axis line in the longitudinal direction.

The air heated in the reformer/heater 4b is supplied to the fuel cell stack 2 through the oxidant gas supply passage 16 and passes through the oxidant gas supply passage (not shown) in the fuel cell stack 2. Are distributed to each fuel cell 2a.
Residual air remaining without being used for power generation in each fuel cell 2a is collected through an oxidant gas discharge passage (not shown) in the fuel cell stack 2 and attached to the top end plate 10a. It is adapted to be discharged to the reforming/heating device 4b through the oxidizing gas discharge passage 18.

Further, as described above, the positions 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 positions where these passages are connected to the fuel cell stack 2 are viewed from above. Are different 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 the single housing 6 (fluid supply device 4) by appropriately changing the connecting passages.
Further, 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, the oxidant gas supply can be provided without increasing the occupied floor area. A passage 16 and an oxidant gas discharge passage 18 can be provided.

Further, the fuel supply passage 12, the fuel discharge passage 14, the oxidant gas supply passage 16 and the oxidant gas discharge passage 18 each have a connection structure using piping screws. Therefore, it can be separated by loosening the connecting nut. As described above, 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 the housing 6, and these passages may be detachably connected to the fuel cell stack 2.

<Structure of evaporator>
Next, the structure of the evaporator 4a will be described with reference to FIGS. 2 and 3. 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 exhausting exhaust gas. The discharge pipe 24 is connected.
Further, the housing 6 of the reforming/heating device 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 for supplying exhaust gas from the reforming/heating device 4b to the evaporator 4a and a mixed gas conduit 28 arranged inside this (FIG. 3).
The mixed gas conduit 28 is configured to introduce, into the reforming/heating device 4b, a mixed gas obtained by mixing the water vapor 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 of the evaporator 4a.

As shown in FIG. 3, the evaporator 4a is formed of a metal plate into a rectangular parallelepiped box shape, and inside thereof, an evaporation chamber 30a, a mixing chamber 30b, and an exhaust gas chamber 30c are formed.
The evaporation chamber 30a is a thin space formed immediately below the ceiling surface of the evaporator 4a, and is supplied from a water supply pipe 20 and a 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 communicating with the downstream side of the evaporation chamber 30a via a narrow passage 30d.
The water vapor generated in the evaporation chamber 30a and the raw fuel gas supplied into the evaporation chamber 30a are mixed by flowing into the mixing chamber 30b through the narrow passage 30d.
The mixed gas conduit 28 is connected to the bottom surface of the mixing chamber 30b. As a result, the steam and the raw fuel gas mixed in the mixing chamber 30b are introduced into the reforming/heating device 4b through the mixed gas conduit 28.

The exhaust gas chamber 30c is a space provided in the lower portion of the evaporator 4a, and is configured so that exhaust gas flows in via an exhaust gas pipe 26 connected to the bottom surface of the evaporator 4a.
The exhaust gas flowing 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 supposed to be done.
The water supplied to the evaporation chamber 30a is evaporated when the floor surface of the evaporation chamber 30a is heated 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).
In this thin space, heat transfer fins 30e are arranged so that the heat of the exhaust gas flowing through the exhaust gas chamber 30c can be 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 exhaust gas discharge pipe 24 side is being evaporated in the evaporation chamber 30a, and toward the other end (FIG. 3). From right to left). In this way, the water vapor and the exhaust gas flowing in the evaporator 4a flow in the opposite directions, so that counterflow type heat exchange is performed between them and the heat exchange is performed efficiently.

<Structure of reformer/heater>
Next, the structure of the reforming/heating unit 4b will be described with reference to FIGS.
As shown in FIG. 2, the reforming/heating device 4b is formed in a rectangular parallelepiped box shape surrounded by a metal housing 6, and its upper surface is supplied with air which is an oxidant gas for power generation. An air supply pipe 32 for connecting is connected. As described above, the upper surface of the housing 6 is a double pipe of the exhaust gas pipe 26 and the mixed gas conduit 28 (FIG. 3), and the bottom surface is the fuel supply passage 12, the fuel discharge passage 14, and the oxidant gas supply passage. 16 and the 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, which is supplied to the fuel cell stack 2 through the fuel supply passage 12 and an air supply pipe. The air introduced via 32 is heated and supplied to the fuel cell stack 2 via the oxidant gas supply passage 16.
Further, the residual fuel gas and the residual air (residual oxidant gas) remaining without being used for power generation in the fuel cell stack 2 are reformed/heated through the fuel discharge passage 14 and the oxidant gas discharge passage 18, respectively. It is designed to be discharged to the container 4b.
The residual fuel gas and residual air discharged through the fuel discharge passage 14 and the oxidant gas discharge passage 18 are combusted in the reformer/heater 4b, and the air introduced from the air supply pipe 32 by this combustion heat. Is designed to be heated. The combustion gas generated by the combustion is introduced into the evaporator 4a as exhaust gas through the exhaust gas pipe 26.

Next, the internal structure of the reforming/heating device 4b will be described with reference to FIGS.
As shown in FIG. 3, a sealed space for housing the reformer 36 and the combustor 38 is formed inside the housing 6 forming the reformer/heater 4b.

The reformer 36 is a metal annular container having a rectangular cross section in a top view and having a rectangular opening in the center, and a mixed gas conduit 28 for introducing a mixed gas is provided at one end thereof. It is connected.
Further, the fuel supply passage 12 for flowing out the reformed fuel gas is connected to the other end of the reformer 36 (FIG. 5).
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 90 degrees vertically downward 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, penetrates the bottom surface of the housing 6 and extends vertically downward, and is connected to the fuel cell stack 2. ing.
The inside of the reformer 36 is filled with a reforming catalyst 36a. The mixed gas of the raw fuel gas and steam flowing from the mixed gas conduit 28 is steam-reformed by coming into contact with the reforming catalyst 36a, and a fuel gas rich in hydrogen gas is generated. 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 burned by the residual air discharged through the oxidant gas discharge passage 18.

As shown in FIG. 6, the combustor 38 includes a residual fuel gas manifold 38a, a residual fuel gas distribution pipe 38b connected to the residual fuel gas manifold 38a, and a residual air distribution plate 38c for dispersing the residual air in 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, and allows the residual fuel gas from the fuel discharge passage 14 connected to the bottom wall surface of the housing 6 to flow into the inside. Is configured.

The residual fuel gas distribution pipe 38b is composed of a pipe having a circular cross section. These pipes extend from the residual fuel gas manifold 38a in parallel in the longitudinal direction of the housing 6, and are joined together by pipes extending in the lateral direction at the other end of the housing 6.
A large number of pores are provided on the upper surface of the pipe forming the residual fuel gas distribution pipe 38b. As a result, the residual fuel gas flowing 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 into 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 oxidant gas discharge passage 18 connected to the bottom wall surface of the housing 6 communicates with the trapezoidal cross section space surrounded by the residual air distribution plate 38c and the bottom wall surface of the housing 6.
Further, a large number of pores are formed on the slopes on both sides of the residual air dispersion plate 38c, and the residual air that has flowed in from the oxidant gas discharge passage 18 is injected into the housing 6 through these pores and dispersed. It is supposed to be done.

As shown in FIGS. 3 and 6, a ceramic heater 34 is attached to the side wall surface of the housing 6, and its tip portion extends to the center of the confluent portion of the residual fuel gas distribution pipe 38b.
When the fuel cell module 1 is started up, the residual fuel gas is ejected from the respective pores of the residual fuel gas distribution pipe 38b, and the residual air is ejected from the respective pores of the residual air distribution plate 38c to the ceramic heater 34. By energizing, it is possible to ignite the residual fuel gas that is being ejected. As a result, the reformer 36 arranged above the combustor 38 in the housing 6 can be heated.
Since the reformer 36 is not heated in the initial stage of starting the fuel cell module 1, the reforming reaction does not occur in the reformer 36 and the fuel cell stack 2 does not generate power. ..

<Structure of oxidant gas heat exchanger>
Next, the oxidant gas heat exchanger provided in the reforming/heating device 4b will be described with reference to FIGS. 3 and 4.
As shown in FIG. 3 and FIG. 4, a part 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 combustion gas is used to heat the air flowing inside.
That is, a part of the upper surface, a part of the side wall surface in the longitudinal direction, and a part 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. The fins 40 for heat transfer 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 oxidant gas, air, 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 forming the upper wall surface of the housing 6 (see FIG. 3), and spreads from here in the lateral direction of the housing 6. , Flows into the space between the inner wall plate 6a and the outer wall plate 6b forming the side wall surface 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 forms the bottom wall surface of the housing 6.
The air flowing into the bottom wall surface of the housing 6 is supplied to the fuel cell stack 2 through the oxidant gas supply passage 16 (FIG. 3) connected to the center of the bottom wall surface of the housing 6 in the lateral direction. It has become.
Therefore, the upper wall surface, the side wall surface, and a part of the bottom wall surface of the housing 6 function as an oxidant gas heat exchanger, and the oxidant gas heat exchanger is provided on these wall surfaces.

<Operation of fuel cell module>
Next, the operation of the fuel cell module 1 according to the first embodiment of the present invention will be described.
First, when the fuel cell module 1 is started, the raw fuel gas is supplied to the evaporator 4 a of the fluid supply device 4 via the raw fuel gas supply pipe 22, and the power generation air is supplied via the air supply pipe 32. Is supplied to the reforming/heating device 4b of the fluid supply device 4.
As shown in FIG. 3, the supplied raw fuel gas flows into the mixed gas conduit 28 through the evaporation chamber 30a and the mixing chamber 30b of the evaporator 4a, and further, the reformer 36 of the reforming/heating device 4b. Flows into.
In the initial stage of starting the fuel cell module 1, since the temperature of the reformer 36 is low, the reaction for reforming the raw fuel gas does not occur. The raw fuel gas flowing 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 reforming/heating unit 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 passes through the oxidant gas supply passage 16 (FIG. 5). It flows through 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 the internal passages and are discharged to the reforming/heating unit 4b via the fuel discharge passage 14 and the oxidant gas discharge passage 18, respectively.
In the initial stage of starting the fuel cell module 1, since the temperature of the fuel cell stack 2 is low, the power generation reaction does not occur in the fuel cell stack 2.

The raw fuel gas flowing into the reformer/heater 4b through the fuel discharge passage 14 flows into the residual fuel gas distribution pipe 38b through the residual fuel gas manifold 38a of the combustor 38, and is ejected from the pores thereof.
On the other hand, the air discharged to the reformer/heater 4b through the oxidant gas discharge passage 18 flows into the inside of the residual air dispersion plate 38c and is ejected from the pores thereof.
When the fuel cell module 1 is activated, 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 the combustor 38 to generate heat of combustion.

When the combustor 38 is ignited, the reformer 36 arranged above the combustor 38 is heated, and the temperature of the internal reforming catalyst 36a rises.
Further, the oxidant gas heat exchanger constituted by the inner wall plate 6a and the outer wall plate 6b of the housing 6 is heated by the combustion gas generated by the combustion, and the air flowing inside is heated.
Since the heated air flows into the fuel cell stack 2, this 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, there is almost no heating of the fuel cell stack 2 due to radiation heat 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.

Further, the combustion gas generated in the housing 6 flows into the evaporator 4a as exhaust gas through the exhaust gas pipe 26.
The exhaust gas flowing 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.
In this way, the water supplied to the evaporator 4 a is heated by the combustion gas generated by the combustor 38 and supplied by the exhaust gas pipe 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.
When the fuel cell module 1 is activated, the electric heater 29 may be energized to assist in heating the evaporation chamber 30a.

When steam is generated in the evaporation chamber 30a, a mixed gas of the raw fuel gas and steam is supplied to the reformer 36.
Further, when the temperature of the reformer 36 is sufficiently increased, the steam reforming reaction is induced by the reforming catalyst 36a, and a fuel gas rich in hydrogen gas is generated 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 is sufficiently increased, the fuel gas and the air heated in the reforming/heating unit 4b cause a power generation reaction. In a state where the temperature of the fuel cell stack 2 has risen to a temperature at which power can be generated, electric power is taken out from the fuel cell stack 2 via the bus bar B1 and power generation is started.

<Effects of the fuel cell module according to 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 for accommodating a laminated fuel cell stack 2 configured by laminating a plurality of flat plate type fuel cell cells 2a is provided. Has not been done. Thereby, the base end side of each bus bar B1, B2 is located 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). Further, it can be easily provided on each of the lower end portions of the fuel cell stack 2 (more specifically, between the lower end surface of the lowermost fuel cell 2a and the upper surface of the bottom end plate 10b).
Further, the structure in which the fuel cell stack 2 is accommodated in the outer container member in consideration of design error and thermal expansion difference between the both can be omitted by eliminating the outer container member.
Furthermore, since the tip ends of the busbars B1 and B2 can be directly and externally protruded outside the fuel cell module 1 without penetrating the outer container member, the outer container member and the busbars B1 and B2 are not connected to each other. It is also possible to omit the structure and components for electrically insulating the spaces.
As a result, by suppressing the number of parts, the manufacturing cost, the product weight, and the product size can be suppressed, and the electric resistance can also be suppressed.

Further, according to the fuel cell module 1 of the present embodiment, the heat insulating material 8 can reduce the 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 the layout change of the reformer 36, the combustor 38 and the like in the housing 6 on the temperature distribution of the fuel cell stack 2.
Further, since the heat insulating material 8 can directly or indirectly restrain 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 container member.

Furthermore, according to the fuel cell module 1 of the present embodiment, the base end portions of the bus bars B1 and B2 are fixed to the upper end portion and the lower end portion of the fuel cell stack 2, respectively, and are directly or indirectly connected by the heat insulating material 8. Since the fixed end portion is constrained, the heat insulating material 8 can suppress heat transfer between the fixed end portion of each of the bus bars B1 and B2 and its peripheral portion.
Further, since the heat insulating material 8 is a non-conductive insulator, it is possible to electrically insulate the fixed end portions of the bus bars B1 and B2 from the peripheral portions thereof.
Furthermore, in addition to the fact that the outer container member that accommodates the fuel cell stack 2 is not provided, the tips of the bus bars B1 and B2 project to the outside of the heat insulating material 8, so that the heat insulating material directly It is a free end that is neither restrained nor indirectly bound. Thereby, the positions of the free ends of the bus bars B1 and B2 are changed according to the positions of the fixed ends of the bus bars B1 and B2 fixed to the upper end and the lower end of the fuel cell stack 2, respectively. Therefore, the degree of freedom in design can be increased.
Therefore, when the electric power generated in the fuel cell 2a is directly taken out of the fuel cell module 1 by the busbars B1, B2, the electric power is taken out according to the position of the free end of each busbar B1, B2. The position and direction can be set freely.

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

Further, according to the fuel cell module 1 of the present embodiment, for each of the bus bars B1 and B2, a surface (upper surface S1 or S3) is formed with respect to a stacking surface Ln on which the plurality of flat plate type fuel battery cells 2a are stacked. ) And the back surface (lower surfaces S2, S4) are parallel to each other, the outer surface of the outermost flat plate-type fuel cell of the fuel cell stack 2 (upper surface of the uppermost fuel cell 2a (uppermost end surface E1)) And the bottom surface (the bottom end surface E2) of the fuel cell 2a in the lowermost stage.
Thereby, the bus bars B1 and B2 can be easily assembled to the upper end portion and the lower end portion 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 reliably hold the heat insulating material 8.
Therefore, the heat insulating material 8 held by the cover member A1 can surely protect the bus bars B1 and B2 and the fuel cell stack 2 from being damaged.

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. 7 is a schematic front view of the entire fuel cell module according to the second embodiment of the present invention with the front heat insulating material and the end plate removed. 8 is an enlarged perspective view of the bus bar portion in the fuel cell module according to the second embodiment of the present invention shown in FIG.
Here, in the fuel cell module according to the second embodiment of the present 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 present invention described above are denoted by the same reference numerals, and The description of 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-shaped 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 in that the fuel cells 2a are arranged so as to be vertical so as to be stacked in the horizontal front-rear direction. 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 busbars B101 and B102 are formed in a long plate shape from a front and rear pair of front and rear busbars B101 and B102. In this respect, the fuel cell module 1 differs from the fuel cell module 1 according to the first embodiment of the present invention described above.
That is, the bus bars B101 and B102 are arranged such that their front surfaces (front surfaces S101 and S103) and back surfaces (rear surfaces S102 and S104) are vertical surfaces, and are also parallel to the stacking surface Ln of each fuel cell 2a. ing.
Further, the tip end portions of the bus bars B101 and B102 can be directly taken out of the fuel cell module 100 without penetrating the outer container member in the horizontal direction (more specifically, in each of the cases shown in FIGS. 7 and 8). The bus bars B101 and B102 are projected to the right side when viewed from the front side).
However, as a modified example of the fuel cell module 100 of the present embodiment, for example, when the lower space can be secured in an installation state other than floor-standing, the front surface (front surface S101, S103) and the rear surface (front surface S101, S103) of each bus bar B101, B102. The rear ends S102, S104) may be arranged such that the front end portions of the bus bars B101, B102 project outward in the vertical direction (downward) in a state where the rear surfaces S102, S104) are vertical surfaces.

<Effects of Fuel Cell Module of Second Embodiment of the Present Invention>
If the front and back surfaces of the busbar are arranged so as to be horizontal, the electric wires from the harness (not shown) are connected to the electric wire connecting portions (terminal holes C1 and C2) at the free end of the busbar. In this state, a downward deformation load (bending load, bending load, etc.) acts on the free ends of the bus bars due to the weight of the electric wires, etc., so that the bus bar itself is easily deformed.
On the other hand, in the fuel cell module 100 of the present embodiment, the electric wires are connected to the electric wire connecting portions (terminal holes C1 and C2) at the free ends of the bus bars B101 and B102, and the electric wires are attached to each other by their own weight or the like. Even if a downward deformation load (bending load, bending load, etc.) is generated at the free ends of the bus bars B101, B102, the front surface (front surface S101, S103) and the back surface (rear surface S102, S104) of each bus bar B101, B102 are It can be arranged to be vertical.
As a result, as compared with the case where the front and back surfaces of each bus bar B101, B102 are arranged in a horizontal plane, a downward deformation load (bending load, bending load, etc.) due to electric wires from a harness (not shown), etc. It is possible to increase the rigidity (bending rigidity, flexural rigidity, etc.) of each bus bar B101, B102 with respect to.
Therefore, in the state where the electric wire from the harness (not shown) is connected to the electric wire connecting portions (terminal holes C1 and C2) of the free ends of the bus bars B101 and B102, the deformation (bending deformation, bending deformation, etc.) of the bus bars B101 and B102 is performed. Since flexural deformation and the like) can be suppressed, it is possible to reduce the risk that the bus bars B101 and B102 and the fuel cell stack 102 are damaged 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 cell units 2a is horizontally stacked so that the stacking surface Ln thereof is a vertical plane, and thus the outermost surface is formed. By assembling the front surface (front surface S101, S103) or the back surface (rear surface S102, S104) of each bus bar B101, B102 to the outer surface (the front surface and the back surface) of the flat type fuel cell 2a, Can be placed.
Therefore, the bus bars B101 and B102 can be easily assembled to the front end portion and the rear end portion of the fuel cell stack 2. Further, by rotating and positioning each bus bar B101, B102 in the vertical plane, it is possible to freely set the position and direction in which electric power is taken out from each bus bar B101, 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 above-described first and second embodiments. Particularly, in the fuel cell modules 1 and 100 of the first and second embodiments described above, the reformer and the combustor are housed in the housing, and the evaporator is arranged outside the housing. The present invention can also be configured to be housed within a housing.
Further, the present invention can be configured such that a desulfurizer that removes a sulfur component contained in the raw fuel gas and a combustion catalyst that removes carbon monoxide and the like in the exhaust gas are housed in the housing.
Further, in the fuel cell modules 1 and 100 of the first and second embodiments described above, the oxidant gas heat exchanger is formed integrally with the outer wall surface of the housing, but the oxidant gas heat exchanger is The present invention can also be configured to be housed inside.
Further, in the above-described fuel cell modules 1 and 100 of the first and second embodiments, the housings are arranged side by side above the fuel cell stack, but the housings may be arranged below the fuel cell stack. The housings may be arranged side by side on the side of the fuel cell stack.

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 Reforming/heater 6 Housing 6a Inner wall plate 6b Outer wall plate 8 Insulation 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 conduit 29 Electric heater 30a Evaporating chamber 30b Mixing chamber 30c Exhaust gas chamber 30d Passage 30e Fin 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 dispersion plate 40 Fin 100 Fuel Cell Module According to Second Embodiment of the Present Invention A1 Cover Member B1 Upper Bus Bar (Bus Bar)
B2 Lower bus bar (bus bar)
B101 Front side bus bar B102 Rear side bus bar C1 Terminal hole (electric wire connection part)
C2 terminal hole (electric wire connection part)
E1 Uppermost end surface of fuel cell E2 Lowermost end surface of fuel cell Ln Laminated surface of fuel cell S1 Upper surface of upper bus bar (surface of bus bar)
S2 Lower surface of upper bus bar (back surface of bus bar)
S3 Upper surface of lower bus bar (surface of bus bar)
S4 Lower bus bar bottom surface (back surface of bus bar)
S101 Front side of front busbar (front of busbar)
S102 Rear side of the front bus bar (back side of the bus bar)
S103 Front of rear busbar (front of busbar)
S104 Rear side of rear side bus bar (back side of bus bar)

Claims (9)

1. A fuel cell module for generating power by reacting a supplied fuel gas with an oxidant gas,
   A sealed fuel cell stack in which the flow paths of the fuel gas and the oxidant gas are defined,
   A reformer that reforms the raw fuel gas to generate a fuel gas containing hydrogen and supplies the fuel gas to the fuel cell stack,
   A combustor that burns the residual fuel gas that is not used for power generation in the fuel cell stack and that heats the reformer,
   A conductive bus bar for extracting electric power generated in the fuel cell,
   The fuel cell module does not include an outer container member that houses the fuel cell stack,
   The bus bar is characterized in that the base end side thereof is provided in the fuel cell stack, and the tip end side thereof directly protrudes outside the fuel cell module without penetrating the outer container member. And a fuel cell module.
2. Furthermore, a housing in which a space for housing the reformer and the combustor is formed, and a heat insulating material arranged to thermally isolate the fuel cell stack from the housing,
   The fuel cell module according to claim 1, wherein the bus bar has its base end side restrained by the heat insulating material.
3. The fuel cell module according to claim 2, wherein the fuel cell stack is surrounded by the heat insulating material.
4. The heat insulating material is a non-conductive insulator, 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 fuel cell module according to claim 2 or 3, wherein the tip portion is a free end portion that protrudes to the outside of the heat insulating material and is not constrained by the heat insulating material.
5. The free end portion of the bus bar includes an electric wire connecting portion to which an electric wire is connected, and the heat insulating material is a cushioning material that suppresses deformation of the bus bar in a state where the electric wire is connected to the electric wire connecting portion. The fuel cell module according to any one of claims 2 to 4.
6. The bus bar is one of the fuel cell stacks so that the front surface or the back surface is parallel to a stacking surface on which the plurality of flat plate fuel battery cells of the sealed fuel cell stack are stacked. 6. The fuel cell module according to claim 1, wherein the fuel cell module is disposed on the outer surface of the outermost flat fuel cell unit.
7. The fuel cell module according to claim 6, wherein the bus bar is formed in a plate shape from the base end portion to the tip end portion in the longitudinal direction, and is arranged such that the front surface or the back surface thereof becomes a vertical plane.
8. 7. The fuel cell module according to claim 6, wherein each of the plurality of flat plate type fuel battery cells is stacked in a horizontal direction so that the stacking surface is a vertical plane.
9. The fuel cell module according to claim 2, further comprising a cover member provided outside the heat insulating material, the cover member configured to hold the heat insulating material. ..

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