JP7001408B2 - Solid oxide fuel cell device - Google Patents

Description

The present invention relates to a fuel cell device. In particular, the present invention relates to a solid oxide fuel cell device that generates power by reacting a fuel gas obtained by reforming a raw material gas with an oxidant gas.

The solid oxide fuel cell (Solid Oxide Fuel Cell: also referred to as "SOFC") uses an oxide ion conductive solid electrolyte as an electrolyte, and a fuel cell with electrodes on both sides thereof is placed in a multi-module container. By disposing and supplying fuel gas to one electrode (fuel electrode) of the fuel cell and supplying oxidizing agent gas (air, oxygen, etc.) to the other electrode (air electrode), power is generated by a power generation reaction. It is a device for extracting electric power, and operates at a relatively high temperature of, for example, about 700 to 1000 ° C., as compared with other fuel cell devices such as a polymer electrolyte fuel cell device.

Examples of the fuel cell used in such a solid oxide fuel cell device include a flat cylindrical cell described in Patent Document 1, a cylindrical single cell described in Patent Document 2, and a cylindrical horizontal stripe type described in Patent Document 3. It has been known.

By the way, as such a solid oxide fuel cell device, a high fuel utilization rate (Uf) in a fuel cell of the fuel gas to be supplied and a high power generation efficiency are required. Therefore, in order to improve the fuel utilization rate and power generation efficiency, the fuel cell arrangement as described in Patent Document 4 and Patent Document 5 is divided into two cell groups to promote the cascade utilization of fuel gas, which is a two-stage configuration. Cascade type fuel cells have been proposed.

Japanese Patent Application Laid-Open No. 2015-082389 Japanese Patent No. 5234554 Japanese Unexamined Patent Publication No. 7-130385 Japanese Unexamined Patent Publication No. 2016-100136 Japanese Unexamined Patent Publication No. 2016-100138

However, when an attempt is made to apply such a two-stage cascade type fuel cell to a fuel cell stack using a conventional tubular fuel cell and a fuel cell device, the device configuration becomes complicated and the fuel cell device becomes smaller. It is difficult to construct easily, such as being hindered.

In particular, the fuel gas has unevenness due to the difference in power generation efficiency due to the temperature unevenness of the fuel cell of the cell group on the primary side. Therefore, if the fuel gas discharged from the fuel cell of the primary side cell group is directly flowed into the fuel cell of the secondary side cell group, the power generation efficiency in the fuel cell of the secondary side cell group is improved. Will also make a difference.

The present invention has been made in view of the above problems, and has a simple configuration that can be applied to miniaturization by suppressing complication of the apparatus, and is a two-stage cascade type fuel cell using a columnar fuel cell. It is intended to provide a stacking device. In particular, it is an object of the present invention to provide a fuel cell stack device capable of reducing unevenness of fuel gas flowing into a cell group on the secondary side.

The fuel cell cell stack device of the present invention includes a first cell stack and a second cell stack in which a plurality of columnar fuel cell cells having a gas flow path extending in the longitudinal direction are juxtaposed in the first direction. A group of cells juxtaposed in the horizontal direction, a first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack, a first cell stack, and a first cell stack. A second cell that is connected to the second cell stack, recovers the fuel gas discharged from the first cell stack, and supplies the recovered fuel gas to each fuel cell of the second cell stack. A fuel cell cell stack device comprising a manifold, the second manifold being connected to a first connection to which the first cell stack is connected and a second connection to which the second cell stack is connected. A part is provided, and in the second manifold, a flow path resistance part that gives resistance to the flow of fuel gas from the part where the first connection part is provided to the part where the second connection part is provided is provided. The flow path resistance portion is composed of a gap formed in the second manifold so as to extend in the first direction, and the height of the gap is smaller than the height of the space in the first connection portion. It is characterized by that.
In the present invention, the height of the gap is preferably smaller than the height of the space in the second connection.

According to the present invention having the above configuration, the fuel gas used in the first cell stack flows into the second cell stack and is further consumed, so that the fuel utilization rate can be increased. Further, since the fuel gas can be consumed in two stages without significantly changing the cell arrangement, it is possible to provide a fuel cell stack having high power generation efficiency and easy to manufacture.

According to the present invention having the above configuration, since the flow path resistance portion is provided in the second manifold, the fuel gas discharged from the first cell stack is dispersed in the second manifold, and the second A uniform fuel gas is supplied to the cell stack.

In the fuel cell cell stack device of the present invention, a first cell stack and a second cell stack in which a plurality of columnar fuel cell stacks having a gas flow path extending in the longitudinal direction are juxtaposed are juxtaposed in the horizontal direction. A first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack, and a first cell stack and a second cell stack. It is provided with a second manifold for recovering the fuel gas discharged from the first cell stack and supplying the recovered fuel gas to each fuel cell of the second cell stack. In the fuel cell cell stack device, the second manifold is provided with a first connection portion to which the first cell stack is connected and a second connection portion to which the second cell stack is connected. In the second manifold, a flow path resistance portion that gives resistance to the flow of fuel gas from the portion provided with the first connection portion to the portion provided with the second connection portion is provided . The manifold 2 is configured so that the height of the second connection portion is lower than the height of the first connection portion.

According to the present invention of the above configuration, the height of the second connection portion connected to the second cell stack is lower than the height of the first connection portion connected to the first cell stack. Therefore, the flow path resistance portion can be easily formed in the second manifold.

In the present invention, preferably, the second manifold has a first frame body in which the first connection portion is formed and a second frame body in which the second connection portion is formed and has the same shape as the first frame body. A frame body and a housing member to which the first frame body and the second frame body are fixed to the upper surface are provided, and the second frame body is from the first frame body with respect to the upper surface of the housing member. Is fixed at a low position, and the flow path resistance portion is formed by a gap between the lower end of the second frame and the bottom surface of the housing member.
According to the present invention having the above configuration, by adjusting the height at which the first frame body and the second frame body are fixed to the housing member, the frame body having the same shape is used, and the second frame body is used. A flow path resistance portion can be easily formed in the manifold.

In the present invention, preferably, the second manifold has a first frame body on which the first connection portion is formed, a second frame body on which the second connection portion is formed, and a first frame body. And a housing member to which the second frame is fixed to the upper surface, and the upper surface of the housing member is a portion to which the second frame is fixed rather than a portion to which the first frame is fixed. The flow path resistance portion is configured to be low, and the flow path resistance portion is configured by a gap between the lower end of the second frame body and the bottom surface of the housing member.
According to the present invention having the above configuration, by changing the height of the portion where the first frame body and the second frame body are fixed on the upper surface of the housing member, the flow path can be easily flown into the second manifold. A resistance portion can be formed.

In the fuel cell cell stack device of the present invention, a first cell stack and a second cell stack in which a plurality of columnar fuel cell stacks having a gas flow path extending in the longitudinal direction are juxtaposed are juxtaposed in the horizontal direction. A first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack, and a first cell stack and a second cell stack. It is provided with a second manifold for recovering the fuel gas discharged from the first cell stack and supplying the recovered fuel gas to each fuel cell of the second cell stack. In the fuel cell cell stack device, the second manifold is provided with a first connection portion to which the first cell stack is connected and a second connection portion to which the second cell stack is connected. In the second manifold, a flow path resistance portion that gives resistance to the flow of fuel gas from the portion provided with the first connection portion to the portion provided with the second connection portion is provided, and further. Located above the second cell stack, it is equipped with a reformer that reforms the raw material gas into a fuel gas containing hydrogen and supplies the fuel gas to the first manifold, and the upper end of the first cell stack is , It is connected to the lower end of the first manifold, and the lower end of the first manifold and the lower end of the reformer are located at the same height.

The second manifold is configured such that the height of the second connection connected to the second cell stack is lower than the height of the first connection connected to the first cell stack. Therefore, the upper end of the second cell stack is located below the upper end of the first cell stack. Therefore, as in the present invention having the above configuration, even if the lower end of the first manifold and the lower end of the reformer are arranged at the same height, the lower portion of the reformer and the second connection portion are connected. It is possible to secure a space for providing a combustion part between the two.

According to the present invention, a two-stage cascade type fuel cell stack and a fuel cell device using a columnar fuel cell are provided with a simple configuration that can be applied to miniaturization by suppressing the complexity of the device. Can be done.

In particular, it is possible to provide a fuel cell stack device capable of reducing unevenness of the fuel gas flowing into the cell group on the secondary side.

It is a side view for demonstrating the basic structure of the fuel cell stack of this invention. It is a figure explaining the fuel consumption of the fuel cell stack of this invention. It is a perspective view which saw from the 1st cell stack side which shows the fuel cell cell stack apparatus by 1st Embodiment of this invention. It is a top view of the fuel cell stacking apparatus according to 1st Embodiment of this invention. It is a partial horizontal sectional view of the 1st cell stack which constitutes the fuel cell cell stack apparatus according to 1st Embodiment of this invention. It is a vertical sectional view of the fuel cell stacking apparatus according to 1st Embodiment of this invention. It is a vertical sectional view of the 1st manifold of the fuel cell stacking apparatus according to 1st Embodiment of this invention. It is an enlarged vertical sectional view of the 2nd manifold of the fuel cell stacking apparatus according to 1st Embodiment of this invention. It is a vertical sectional view which shows the modification of the 2nd manifold of the fuel cell stack device by 1st Embodiment of this invention. It is a figure which shows the fuel cell according to the 2nd Embodiment of this invention. It is a figure which shows the fuel cell according to the 2nd Embodiment of this invention. It is a side view which shows the fuel cell stack by 2nd Embodiment of this invention. It is a side view which shows the fuel cell stack by 2nd Embodiment of this invention.

Hereinafter, embodiments of the invention disclosed in the present specification will be described in detail with reference to the drawings. From the following description, many improvements and other embodiments of the present invention will be apparent to those skilled in the art. Therefore, the following description should be construed as an example only and is provided for the purpose of teaching those skilled in the art the best embodiments of the present invention. The details of its structure and / or function can be substantially modified without departing from the spirit of the present invention.

First, the basic configuration of the present invention will be described. FIG. 1 is a side view for explaining the basic configuration of the fuel cell stack 100 of the present invention. As shown in FIG. 1, the fuel cell stack 100 is composed of a plurality of columnar cells 1 having a gas flow path inside, a manifold 2b, and a manifold 2a. The cell 1 is supported and fixed with one end side (lower end side in FIG. 1) standing upright on one manifold 2b. Here, in the plurality of cells 1, a manifold 2a is installed on the other end side (upper end side in FIG. 1), and the cell group 10a fixed to the manifold 2a and the other end side are open without being connected to the manifold 2a. It is divided into the cell group 10b and the cell group 10b. The plurality of cells 1 are connected to each other so as to be electrically connected in series (not shown).

When the fuel gas is supplied to the inside of the manifold 2a, the fuel gas flows from the other end side to the one end side of the cell group 10a, and the fuel gas flowing into the manifold 2b is dispersed in the manifold 2b, and the cell group 10b After flowing from one end side to the other end side, the fuel cell group 10b is discharged to the outside of the fuel cell stack 100 from the other end side.

Here, fuel consumption will be described with reference to FIGS. 2 (A) and 2 (B).

As shown in FIG. 2A, when the fuel gas is consumed in two stages of the cell group 10a and the cell group 10b to generate power, the fuel gas including the reformed gas supplied to the manifold 2a is set to 100. Assuming that the amount consumed by the cell group 10a is 40, the fuel utilization rate (Uf) is 40% because the cell group 10a is calculated as 40 ÷ 100 = 0.4. Further, the unused fuel gas discharged from the cell group 10a is 60, which is supplied to the cell group 10b. Assuming that the amount consumed by the cell group 10b is 40, which is the same as the cell group 10a, the fuel utilization rate in the cell group 10b is 40 ÷ 60 = 0.667 ..., So the fuel utilization rate is about 67%. ..

On the other hand, when power is not generated in two stages, that is, when power is generated in one stage, the fuel is similarly 100, and the amount consumed by the cell group is consumed in one stage, so if it is 80, 80 ÷ 100 = 0. Calculated as 0.8, the fuel utilization rate Uf is 80%.

When the fuel utilization rate is 80% or more, the partial pressure of water vapor becomes too high and the electromotive force of the cell decreases. That is, because it is affected by Nernstros, the potential tends to decrease, and the power generation efficiency decreases. Further, if the fuel utilization rate becomes too high, the risk of oxidation of the electrode of the cell increases, and the durability of the cell deteriorates.

From the above points, by forming a plurality of cells into a cell group 10a and a cell group 10b so as to have two stages and causing a power generation reaction, the fuel utilization rate of each cell group is maintained low and the fuel cell stack is maintained. As a whole, the fuel utilization rate (that is, power generation efficiency) can be increased.

In the present specification, the cell group 10a on the upstream side of the cell group separated into two stages in order to realize the cascade use of fuel gas is referred to as "first stage cell group", "first cell stack", and "first cell stack". Alternatively, it may be called a "primary cell group", and the downstream cell group 10b may be called a "second stage cell group", a "second cell stack", or a "secondary cell group", but both of them may be called. It is synonymous.

As described above, a plurality of cells are configured by allowing fuel gas to flow in from the manifold on the other end side, collecting unused gas in the manifold on the one end side, and supplying it to the cell group on the open side. Conventional fuel by simply adjusting the number of cells on the upstream side and the downstream side without significantly restricting or hindering the arrangement of cells, the electrical series connection between cells, the flow of air for power generation, etc. It is possible to provide a fuel cell stack having a high fuel utilization rate to which the structure of the battery module can be applied as it is.

Further, by arranging the reformer or the evaporator in the combustion region where the off gas discharged from the fuel cell stack is burned, it is possible to apply the same arrangement configuration as the conventional fuel cell module. Therefore, it is possible to support a small fuel cell device having an output performance of about 1 kW, and to provide a highly efficient and highly durable fuel cell system.

Hereinafter, the fuel cell stacking device according to the first embodiment of the present invention will be described. FIG. 3 is a perspective view showing the fuel cell cell stack device according to the first embodiment of the present invention as viewed from the first cell stack side. FIG. 4 is a top view of the fuel cell stack device according to the first embodiment of the present invention. FIG. 5 is a partial horizontal sectional view of a first cell stack constituting the fuel cell cell stack device according to the first embodiment of the present invention. FIG. 6 is a vertical sectional view of the fuel cell stack device according to the first embodiment of the present invention. FIG. 7 is a vertical sectional view of a first manifold of the fuel cell stack device according to the first embodiment of the present invention. FIG. 8 is an enlarged vertical sectional view of a second manifold of the fuel cell stack device according to the first embodiment of the present invention. The partition plate is omitted in FIGS. 3 and 4.

As shown in FIGS. 3 to 6, the fuel cell stack device 100 includes a first cell stack 10a, a second cell stack 10b composed of a plurality of columnar fuel cell cells 1, and a first cell. A first manifold 2a provided above the stack 10a, a manifold 2b provided below the first cell stack 10a and the second cell stack 10b, and above the second cell stack 10b. It is composed of a reformer 12 having a reforming unit B filled with a reforming catalyst. The reformer 12 and the first manifold 2a are fluidly connected via a connecting portion 14. Further, a partition plate 60 is provided between the first cell stack 10a and the second cell stack 10b.

As shown in FIG. 6, the fuel cell stack device 100 is surrounded by the heat insulating material 90. An inner housing 92 is provided on the outer periphery of the heat insulating material 90, and an outer housing 94 is attached to the outer periphery of the inner housing 92. An exhaust gas flow path 96 is formed between the inner housing 92 and the heat insulating material 90. Further, an air flow path 98 is formed between the inner housing 92 and the outer housing 94. The upper end of the partition plate 60 is connected to the inner housing 92. An exhaust gas discharge hole 92a that communicates with the exhaust gas flow path 96 and extends to the outside of the outer housing 94 is formed on the lower surface of the inner housing 92. Further, on the lower surface of the outer housing 94, an air inflow hole (not shown) that communicates with the air flow path 98 and extends to the outside of the outer housing 94 is formed.

The first cell stack 10a is formed by arranging a plurality of columnar fuel cell cells 1a having a gas flow path extending in the axial direction inside in a row in the horizontal direction (horizontal direction). Further, in the second cell stack 10b, similarly to the first cell stack 10a, a plurality of columnar fuel cell cells 1b having a gas flow path extending in the axial direction inside are arranged in a horizontal direction (horizontal direction). It is arranged in.

The upper end of each fuel cell 1a constituting the first cell stack 10a is fluidly connected to the first manifold 2a. Further, the lower end of each fuel cell 1a constituting the first cell stack 10a is fluidly connected to one side in the short side direction of the second manifold 2b. The lower end of each fuel cell 1b constituting the second cell stack 10b is fluidly connected to the other side in the short side direction of the second manifold 2b. The upper end of each fuel cell 1b constituting the second cell stack 10b is open, and the upper end of the second cell stack 10 and the reformer 12 are separated from the second cell stack 10b. A combustion unit 18 is formed in which the released gas is burned.

Raw material gas and water (or steam) are supplied to the reformer 12. The reformer 12 reforms the fuel gas supplied by the heat of the combustion unit 18 into a fuel gas containing hydrogen. The fuel gas reformed by the reformer 12 is supplied to the first manifold 2a via the connecting portion 14. The fuel gas supplied to the first manifold 2a is sent to the fuel cell 1a constituting the first cell stack 10a and flows downward into the internal flow path of the fuel cell 1a. At this time, power is generated by the fuel cell 1a of the first cell stack 10a.

The fuel gas discharged from the fuel cell 1a of the first cell stack 10a is recovered by the second manifold 2b. The fuel gas recovered by the second manifold 2b is supplied to the internal flow path of the fuel cell 1b constituting the second cell stack 10b, and flows upward in the internal flow path. At this time, power is generated by the fuel cell 1b of the second cell stack 10b.

The fuel gas that has passed through the fuel cell 1b of the second cell stack 10b is discharged to the combustion unit 18 above the second cell stack 10b. Then, the fuel gas discharged to the combustion unit 18 and not used for power generation is ignited and burned. In this embodiment, the cell group includes only one first cell stack 10a and one second cell stack 10b. However, two or more first cell stacks may be provided, two or more second cell stacks may be provided, and a third cell stack may be provided downstream of the second cell stack.

As shown in FIG. 5, in the first cell stack 10a, a plurality of fuel cell cells 1a are arranged side by side at intervals in a row, and a current collector member 30 is arranged between adjacent fuel cell cells 1a. It is configured. As a result, the plurality of fuel cell cells 1a are electrically connected in series. Further, the end current collector member 30a is adhered to the fuel cell 1a located on the outermost side of the first cell stack 10a. Similarly to this, the end current collector member 30b is adhered to the fuel cell 1b located on the outermost side of the second cell stack 10b. On one side of the fuel cell cell stack device 100, the end current collector 30a of the first cell stack 10a is connected to the end current collector 30b of the second cell stack 10b via a connected current collector 32. Has been done. As a result, the fuel cell 1a constituting the first cell stack 10a and the fuel cell 1b constituting the second cell stack 10b are connected in series. Then, the current generated from the end current collecting member 30a of the first cell stack 10a on the other side of the fuel cell cell stack device 100 and the end current collecting member 30b of the second cell stack 10b is taken out. .. In the present embodiment, the fuel cell 1a constituting the first cell stack 10a and the fuel cell 1b constituting the second cell stack 10b are connected in series, but may be connected in parallel. It is possible.
Inside each fuel cell 1a, a gas flow path penetrating from one end to the other is formed.

The fuel cell 1a has a columnar conductive support substrate 34 having a pair of facing flat surfaces, a fuel side electrode layer 36 formed on one flat surface of the support substrate 34, and an outer surface of the fuel side electrode layer 36. It is composed of a solid electrolyte layer 38 formed in the solid electrolyte layer 38 and an air side electrode layer 40 formed on the outer surface of the solid electrolyte layer 38. Further, an interconnector 42 is provided on the other flat surface of the fuel cell 1a.

Inside the support substrate 34, a gas flow path 34A for flowing fuel gas in the axial direction is formed between both ends. A P-type semiconductor layer 44 is provided on the outer surface of the interconnector 42. The interconnector 42 is connected to the current collector member 30 via the P-type semiconductor layer 44.

The fuel side electrode layer 36 includes, for example, a mixture of Ni and zirconia doped with at least one selected from rare earth elements such as Ca, Y, and Sc, Ni, and ceria doped with at least one selected from rare earth elements. A mixture of Ni and a lanthanum garade doped with at least one selected from Sr, Mg, Co, Fe and Cu.

The solid electrolyte layer 38 is, for example, zirconia doped with at least one selected from rare earth elements such as Y and Sc, and lanthanum gallate doped with at least one selected from ceria, Sr, and Mg doped with at least one selected from rare earth elements. , Formed from at least one of.

The air-side electrode layer 40 is, for example, a lanthanum manganite doped with at least one selected from Sr and Ca, a lanthanum ferrite doped with at least one selected from Sr, Co, Ni and Cu, Sr, Fe and Ni. It is formed from at least one of lanthanum cobaltite, silver, etc. doped with at least one selected from Cu.

As the support substrate 34, conductive ceramics or cermet having a high aperture ratio can be used so that the fuel gas has gas permeability so as to penetrate to the fuel side electrode layer 36. The shape of the support substrate 34 may be columnar or cylindrical.

As the P-type semiconductor layer 44, for example, P-type semiconductor ceramics composed of at least one such as LaMnO3-based oxide, LaFeO3-based oxide, and LaCoO3-based oxide in which Mn, Fe, Co, etc. are present at the B site are used. Can be done.

As the interconnector 11, a lanthanum romite-based perovskite-type oxide (LaCrO3-based oxide), a lanthanum strontium titanium-based perovskite-type oxide (LaSrTiO3-based oxide), or the like can be used.

The configuration of the first cell stack 10a and the configuration of the second cell stack 10b are the same. As shown in FIG. 3, the first cell stack 10a and the second cell stack 10b are arranged so that the arrangement directions of the fuel cell cells 1a and 1b are parallel to each other. In the following description, the arrangement direction of the fuel cell cells 1a and 1b is simply referred to as the arrangement direction.

The upper part of the fuel cell 1b constituting the second cell stack 10b is open, and the combustion unit 18 is formed above the second cell stack 10b. In the combustion unit 18, fuel gas that has not been used for power generation is burned.

As shown in FIGS. 3 and 4, the reformer 12 includes an evaporation unit 12A and a reformer unit 12B. Raw material gas and water or steam are supplied to the reformer 12 from the outside through supply pipes 13A and 13B. The evaporation unit 12A heats water by the combustion heat of the combustion unit 18 to generate steam.

The reforming section 12B is filled with a reforming catalyst for reforming the mixed gas. As the reforming catalyst, a catalyst in which nickel is added to the surface of an alumina sphere or a catalyst in which ruthenium is added to the surface of an alumina sphere is appropriately used. The reforming unit 12B reforms the raw material gas supplied by the combustion heat of the combustion unit 18 with steam to reform it into a fuel gas containing hydrogen. As shown in FIGS. 3 and 6, the reforming unit 12B is not located above the first cell stack 10a, but is located only above the second cell stack 10b. Further, in the present embodiment, the entire reformer 12 is not located above the first cell stack 10a, but is positioned so as to cover only above the second cell stack 10b (that is, evaporation). The portion 12A, the peripheral flange, and the like are also located only above the second cell stack 10b). The reformer 12 is held so that the bottom surface is horizontal. The bottom surface (lower end portion) of the reformer 12 is located at the same height as the bottom surface (lower end portion) of the first manifold 2a.

As shown in FIG. 7, the first manifold 2a includes a housing 22, a frame body 24, and a distribution pipe 20. The housing 22 is hollow, and an opening 22A having substantially the same shape as the frame body 24 is formed on the lower end surface. The first manifold 2a is held so that the bottom surface of the housing 22 is horizontal.

The frame body 24 is formed with a plurality of openings 24A having substantially the same cross-sectional shape as the fuel cell 1a constituting the first cell stack 10a. The upper ends of all the fuel cell 1a constituting the first cell stack 10a are connected to the opening 24A formed in the frame body 24. The frame body 24 is attached to the opening 22A formed in the housing 22. The connection structure between the first manifold 2a including the connection structure between the housing 22 of the first manifold 2a and the frame body 24 and the upper end portion of the fuel cell 1a is the second manifold 2b and the fuel cell 1a. It is the same as the connection structure at the lower end of the above, and will be described in detail later.

The upstream end of the distribution pipe 20 is fluidly connected to the connection portion 14, and the reformed fuel gas is supplied. A plurality of openings 20A are formed in the distribution pipe 20 with a gap in the longitudinal direction. The opening area of the plurality of openings 20A is larger toward the upstream side. As a result, the fuel gas is evenly distributed to the downstream end of the first manifold 2a, and the fuel gas is evenly supplied to each fuel cell 1a constituting the first cell stack 10a. That is, the distribution pipe 20 functions as a distribution mechanism for evenly supplying the fuel gas to the first fuel cell 1a. The distribution mechanism is not limited to the configuration of the present embodiment. For example, a plurality of partition plates are provided in the first manifold 2a so as to block the internal flow path, and the plurality of partition plates are provided toward the tip thereof. It is also possible to adopt a configuration in which an opening is provided so as to be large.

The connecting portion 14 is seamlessly integrally configured with the reformer 12 and the first manifold 2a, and the internal flow paths of the reformer 12 and the first manifold 2a are fluidly connected to each other. Further, the connecting portion 14 has a shape curved from the reformer 12 toward the first manifold 2a.

As shown in FIG. 8, the second manifold 2b includes a housing member 50, a first frame body 52, and a second frame body 54 having the same shape as the first frame body 52. The housing member 50 includes a substantially rectangular bottom plate 50a, a side plate 50b erected around the bottom plate 50a, and a top plate 50c which is an upper surface of the housing member 50 and closes above the side plate 50b. The top plate 50c is formed in parallel so that the first opening 50d and the second opening 50e are aligned in the width direction so as to extend in the longitudinal direction on both sides in the width direction. The first frame 52 is attached to the first opening 50d of the housing member 50 by the glass seal 56b, and the second frame 54 is attached to the second opening 50e by the glass seal 57b. There is.

The first frame body 52 includes a top plate 52b and a side plate 52c extending downward from the periphery of the top plate 52b, and has a U-shaped cross-sectional shape such that the lower side is open. The top plate 52b of the first frame 52 is formed with a plurality of openings 52a having substantially the same cross-sectional shape as the fuel cell 1a constituting the first cell stack 10a. Therefore, the top plate 52b of the first frame body 52 constitutes a first connection portion to which the first cell stack 10a is connected. The lower ends of the plurality of fuel cell 1a constituting the first cell stack 10a are connected to the opening 52a formed in the first frame 52 by the glass seal 56a.

Further, the second frame body 54 includes a top plate 54b and a side plate 54c extending downward from the periphery of the top plate 54b, and has a U-shaped cross-sectional shape such that the lower side is open. The top plate 54b of the second frame body 54 is formed with a plurality of openings 54a having substantially the same cross-sectional shape as the fuel cell 1b constituting the second cell stack 10b. Therefore, the top plate 54b of the second frame body 54 constitutes a second connection portion to which the second cell stack 10b is connected. The lower ends of the plurality of fuel cell 1b constituting the second cell stack 10b are connected to the opening 54a formed in the second frame 54 by the glass seal 57a.

In the first frame body 52, the vicinity of the lower end portion of the side plate 52c is attached to the first opening 50d of the housing member 50. On the other hand, in the second frame body 54, the vicinity of the upper end portion of the side plate 54c is attached to the second opening 50e of the housing member 50. As a result, the first frame 52 is arranged at a higher position than the second frame 54. Further, the height of the second connection portion between the fuel cell stack 1b of the second cell stack 10b and the second frame 54 is such that the fuel cell stack 1a and the first cell stack 10a of the first cell stack 10a have different heights. It is lower than the height of the first connection between the frames 52.

As described above, in the present embodiment, in the second manifold 2b, the housing member 50 of the second frame body 54 has its top plate 54b lower than the top plate 52b of the first frame body 52. It is fixed to the top plate 50c of. With such a configuration, a narrow gap is formed between the lower end of the second frame 54 and the bottom surface of the housing member 50. This gap is the flow of fuel gas in the second manifold 2b from the first connection portion to which the first cell stack 10a is connected to the second connection portion to which the second cell stack 10b is connected. Acts as a flow path resistance part that gives resistance to.

The partition plate 60 is made of a hollow plate material having heat resistance such as stainless steel, and an air flow passage 60a is formed to supply air to the inside. The upper end of the partition plate 60 is connected to the upper surface of the inner housing 92, and the air flow passage 60a communicates with the air passage 98. As a result, power generation air is supplied to the air flow passage 60a from the upper end via the air flow passage 98. The lower end of the partition plate 60 extends in the vertical direction from a height position above the reformer 12 to the vicinity of the lower ends of the first cell stack 10a and the second cell stack 10b. As a result, the partition plate 60 can partition the connection portion between the first manifold 2a and the first cell stack 10a and the combustion portion 18 to reduce the influence of heat.

The partition plate 60 is formed with an upper through hole 60b penetrating between the facing surfaces 60A and 60B and a lower through hole 60c. The upper through hole 60b is formed at a height above the combustion portion 18. Further, the lower through hole 60c is formed below the combustion portion 18 and is formed at an intermediate height position between the first cell stack 10a and the second cell stack 10b. Through the upper through hole 60b and the lower through hole 60c, the space on the side of the first cell stack 10a and the space on the side of the second cell stack 10b communicate with each other.

Further, a lower end ejection hole 60d is formed at the lower end portion of the partition plate 60. A first air ejection hole 60e is formed on the surface 60A on the first cell stack 10a side of the partition plate 60, and a second air ejection hole 60e is formed on the surface 60B on the second cell stack 10b side of the partition plate 60. An air ejection hole 60f is formed. The first air ejection hole 60e is formed at a height position corresponding to the lower part of the first cell stack 10a. The second air ejection hole 60f is formed at a height position corresponding to the lower part of the second cell stack 10b. The first and second air ejection holes 60e and 60f may be a plurality of openings or a single opening. The total area of the second air ejection holes 60f formed on the surface 60B on the second cell stack 10b side is the total area of the first air ejection holes 60e formed on the surface 60A on the first cell stack 10a side. Is bigger than. A large amount of air supplied to the air flow passage 60a of the partition plate 60 is ejected toward the second cell stack 10b rather than the first cell stack 10a.

Further, a third air ejection hole 60g is formed on the surface 60B of the partition plate 60 on the second cell stack 10b side toward the combustion portion 18. The third air ejection hole 60 g is formed at a height position corresponding to the combustion portion 18. As a result, the air supplied to the air flow passage 60a of the partition plate 60 is ejected toward the combustion portion 18 through the third air ejection hole 60g.

In the present embodiment, the air ejection holes 60e and 60f are provided on both the facing surfaces 60A and 60B of the partition plate 60, but the present invention is not limited to this, and the air ejection holes 60e and 60f are provided only on the surface 60B on the second cell stack 10b side. You may.

Hereinafter, the fuel gas and water (steam) in the fuel cell stack device 100 of the present embodiment and the flow of air for power generation will be described.
The raw material gas and water (steam) are supplied to the fuel cell stack device 100 from the outside through the supply pipes 13A and 13B to the reformer 12. The water supplied to the reformer 12 is evaporated by the heat of the combustion unit 18 in the evaporation unit 12A of the reformer 12. Then, the raw material gas and steam are sent to the reforming unit 12B. The raw material gas and steam are reformed into a fuel gas containing hydrogen by the heat of the combustion unit 18 in the reforming unit 12B.

The reformed fuel gas in the reformer 12 is supplied to the distribution pipe 20 of the first manifold 2a via the connecting portion 14. The fuel gas supplied to the distribution pipe 20 is ejected into the housing 22 through the opening 20A. Here, since the opening area of the opening 20A is larger toward the upstream side, the fuel gas is uniformly ejected into the housing 22. Then, the fuel gas ejected into the housing 22 is sent from the upper end to the internal flow path of each fuel cell 1a constituting the first cell stack 10a. The fuel gas flows from the upper end to the lower end of the fuel cell 1a and is discharged from the lower end into the second manifold 2b. At this time, each fuel cell 1a generates electricity.

As described above, the second frame body 54 of the second manifold 2b is attached to the top plate 50c of the housing member 50 so that the top plate 54b thereof is lower than the top plate 52b of the first frame body 52. It is fixed. Therefore, a narrow gap is formed between the lower end of the second frame 54 and the bottom surface of the housing member 50, and the second cell stack is connected to the first cell stack 10a from the first connection portion. Resistance is given to the flow of fuel gas to the second connection to which 10b is connected. As a result, the fuel gas released to the second manifold 2b is dispersed in the room 2b1 on the upstream side of the second manifold 2b where the first connection portion is provided, and then the second connection portion is provided. It flows into the room 2b2 on the downstream side.

The fuel gas that has flowed into the chamber 2b2 is sent from the lower end to the internal flow path of the fuel cell 1b constituting the second cell stack 10b. The fuel gas sent to the fuel cell 1b flows in the internal flow path from the lower end to the upper end. At this time, each fuel cell 1b generates electricity.

The fuel gas that has passed through the fuel cell 1b constituting the second cell stack 10b and has not been used for power generation is discharged from the upper end of the fuel cell 1b to the combustion unit 18. The fuel gas released to the combustion unit 18 is burned, and the heat generated at that time is used to heat the reformer 12.

The exhaust gas generated by burning the fuel gas in the combustion unit 18 rises upward. At this time, since the upper through hole 60b is formed in the partition plate 60, the exhaust gas is diffused between the first cell stack 10a side and the second cell stack 10b side, and the first cell stack 10a side and the first cell stack 10a side. The temperature difference of the exhaust gas from the cell stack 10b side of 2 becomes small. Then, the exhaust gas flows downward in the exhaust gas flow path 96. At this time, heat exchange is performed between the exhaust gas flowing through the exhaust gas flow path 96 and the power generation air flowing through the air flow path 98, and the power generation air can be heated. Then, the exhaust gas is discharged to the outside of the outer housing 94 from the exhaust gas discharge hole 92a.

Next, the power generation air is sent from the outside to the air flow path 98 through the air inflow hole. The air sent into the air flow path 98 flows upward in the air flow path 98. At this time, heat exchange is performed with the exhaust gas flowing through the exhaust gas flow path 96, and the air is heated. The air that has reached the upper part of the air flow path 98 is sent from the upper end of the partition plate 60 to the air flow passage 60a.

The power generation air sent into the air flow passage 60a is ejected toward the first cell stack 10a and the second cell stack 10b through the first and second air ejection holes 60e and 60f and the lower end ejection holes 60d. To. At this time, the total area of the second air ejection holes 60f formed on the surface 60B on the second cell stack 10b side is the first air ejection holes 60e formed on the surface 60A on the first cell stack 10a side. Since it is larger than the total area of the cell stack 10b, a larger amount of air is ejected toward the second cell stack 10b than in the first cell stack 10a.

Here, since the lower through hole 60c is formed in the partition plate 60, the air on the first cell stack 10a side and the air on the second cell stack 10b side are mixed. As a result, it is possible to suppress the occurrence of temperature unevenness in the air for power generation.

Further, the power generation air sent into the air flow passage 60a is ejected from the third air ejection hole 60g toward the combustion portion 18. As a result, the fuel gas that has not been used for power generation can be completely burned in the combustion unit 18.

As described above, according to the present embodiment, the following effects are exhibited.
According to the present embodiment, the fuel gas used in the first cell stack 10a flows into the second cell stack 10b and is further consumed, so that the fuel utilization rate can be increased. Further, since the fuel gas can be consumed in two stages without significantly changing the arrangement of the fuel cell cells 1a and 1b, it is possible to provide a fuel cell stack device having high power generation efficiency and easy to manufacture. can.

Further, according to the present embodiment, since the flow path resistance portion is provided in the second manifold 2b, the fuel gas discharged from the first cell stack 10a into the second manifold 2b is dispersed. A uniform fuel gas is supplied to the second cell stack 10b.

The configuration of the second manifold 2b is not limited to the configuration described above. FIG. 9 is a vertical sectional view showing a modified example of the second manifold of the fuel cell stack device according to the first embodiment of the present invention. The same components as those in the embodiment described with reference to FIG. 8 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 9, the second manifold 102b includes a housing member 150, a first frame body 52, and a second frame body 54. The housing member 150 includes a substantially rectangular bottom plate 150a, a side plate 150b erected around the bottom plate 150a, and a top plate 150c which is an upper surface of the housing member 150 that closes the upper side of the side plate 150b. The top plate 150c has a first top plate portion 150c1 extending horizontally on the connected side of the first cell stack 10a and a second top plate portion 150c extending horizontally on the connected side of the second cell stack 10b. It includes 150c2 and a vertically extending connecting portion 150c3 that connects between the first top plate portion 150c1 and the second top plate portion 150c2. The first top plate portion 150c1 is provided at a position higher than the second top plate portion 150c2.

The first top plate portion 150c1 of the top plate 150c is formed with a first opening 150d so as to extend in the longitudinal direction on both sides in the width direction. A second opening 50e is formed in the second top plate portion 150c2 of the top plate 150c. The first frame 52 is attached to the first opening 150d of the housing member 150 by the glass seal 56b, and the second frame 54 is attached to the second opening 150e by the glass seal 57b. There is.

In the first frame body 52, the vicinity of the lower end portion of the side plate 52c is attached to the first opening 150d of the housing member 150. Further, in the second frame body 54, the vicinity of the lower end portion of the side plate 54c is attached to the second opening 150e of the housing member 150.

Since the first top plate portion 150c1 is provided at a position higher than the second top plate portion 150c2, the first frame body 52 is arranged at a higher position than the second frame body 54. .. Further, the height of the second connection portion between the fuel cell stack 1b of the second cell stack 10b and the second frame 54 is such that the fuel cell stack 1a and the first cell stack 10a of the first cell stack 10a have a height of the second connection portion. It is lower than the height of the first connection portion with the frame body 52 of.

As described above, in the present embodiment, in the second manifold 102b, the housing member 150 of the second frame body 54 has its top plate 54b lower than the top plate 52b of the first frame body 52. It is fixed to the top plate 150c of. With such a configuration, a narrow gap is formed between the lower end of the second frame 54 and the bottom surface of the housing member 150. This gap is the flow of fuel gas in the second manifold 2b from the first connection portion to which the first cell stack 10a is connected to the second connection portion to which the second cell stack 10b is connected. Acts as a flow path resistance part that gives resistance to.

Further, in the embodiment described with reference to FIGS. 8 and 9, a flow path resistance portion is formed by forming a narrow gap between the bottom plate of the second manifold and the lower end of the second frame body 54. However, the present invention is not limited to this, and for example, a convex portion or the like may be formed on the bottom plate of the second manifold to provide a portion having a narrow flow path area, and this may be used as the flow path resistance portion.

As described above, according to the present embodiment, the following effects are exhibited.
According to the present embodiment, the fuel gas used in the first cell stack 10a flows into the second cell stack 10b and is further consumed, so that the fuel utilization rate can be increased. Further, since the fuel gas can be consumed in two stages without significantly changing the arrangement of the fuel cell cells 1a and 1b, it is possible to provide a fuel cell stack device having high power generation efficiency and easy to manufacture. can.

Further, according to the present embodiment, since the flow path resistance portion is provided in the second manifold 2b, the fuel gas discharged from the first cell stack 10a is dispersed in the second manifold 2b. A uniform fuel gas is supplied to the second cell stack 10b.

Further, according to the present embodiment, the height of the second connection portion to which the second cell stack 10b is connected is lower than the height of the first connection portion to which the first cell stack 10a is connected. Based on this difference in height, a flow path resistance portion having a narrow flow path area can be formed in the second manifold 2b.

Further, in the embodiment shown in FIG. 8 of the present embodiment, the height of the second frame body 54 is higher than the height of the first frame body 52 in the first frame body 52 and the second frame body 54. It is fixed to the housing member 50 so as to be low. In this way, by adjusting the height at which the first frame body 52 and the second frame body 54 are fixed to the housing member 50, the flow path resistance portion can be formed in the second manifold 2b. can.

Further, in the embodiment shown in FIG. 9 of the present embodiment, the housing member 150 is the housing member rather than the height of the first top plate portion 150c1 to which the first frame body 52 of the housing member 150 is fixed. The height of the second top plate portion 150c2 to which the second frame body 54 of the 150 is fixed is set to be low. In this way, by changing the height of the portion where the first frame body 52 and the second frame body 54 of the housing member 150 are fixed, the flow path resistance portion is formed in the second manifold 102b. be able to.

Further, as described above, in the present embodiment, the second manifold 2b is the height of the connection portion connected to the second cell stack 10b rather than the height of the connection portion connected to the first cell stack 10a. Is configured to be low, so that the upper end of the second cell stack 10b is located below the upper end of the first cell stack 10a. Therefore, even if the lower end portion of the first manifold 2a and the lower end portion of the reformer 12 are arranged at the same height as in the present embodiment, the lower portion of the reformer 12 and the second connection portion are connected. It is possible to secure a space for providing the combustion unit 18 between the and.

Next, the fuel cell stack device according to the second embodiment of the present invention will be described.
First, the fuel cell used in the second embodiment of the present invention will be described with reference to FIGS. 10 and 11.

(Fuel cell)
FIG. 10 is a diagram showing cells constituting the cell stack according to the second embodiment of the present invention. FIG. 11 is an enlarged cross-sectional view of the end of the cell.

As shown in FIG. 10, the cell 1001 includes a cell main body 1101 and a cap 1102 (also referred to as a metal cap) which is a connection electrode portion connected to both ends of the cell main body 1101.

As shown in FIG. 11, the cell body 1101 having a conductive support as a support is a tubular structure extending in the vertical direction, and is a fuel gas flow path 1103 (also referred to as an internal flow path) which is a gas passage inside. The inner electrode layer 1104, which is a cylindrical fuel electrode layer, the electrolyte layer 1105, which is a cylindrical solid electrolyte layer provided on the outer periphery of the inner electrode layer 1104, and the cylinder provided on the outer periphery of the electrolyte layer 1105. It includes an outer electrode layer 1106, which is an air electrode (oxidant gas electrode) layer of the shape. The inner electrode layer 1104 is a porous body that functions as a support constituting the cell body 1101 and also constitutes a gas passage through which fuel gas flows. The inner electrode layer 1104 is a fuel electrode and has a (−) pole, while the outer electrode layer 1106 is an air electrode in contact with air and has a (+) pole.

The inner electrode layer 1104 is composed of, for example, a mixture of Ni and zirconia doped with at least one selected from rare earth elements such as Ca, Y, and Sc, and Ni and ceria doped with at least one selected from rare earth elements. It is formed from at least one of a mixture of Ni and a lanthanum garade doped with at least one selected from Sr, Mg, Co, Fe and Cu. In this embodiment, the inner electrode layer 1104 is made of Ni / YSZ.
A porous insulating support can also be used as the support, and in this case, a fuel electrode layer is formed as an inner electrode layer on the outer side of the insulating support.

The electrolyte layer 1105 is formed over the entire circumference along the outer peripheral surface of the inner electrode layer 1104, the lower end is terminated above the lower end of the inner electrode layer 1104, and the upper end is below the upper end of the inner electrode layer 1104. It is terminated. The electrolyte layer 1105 is, for example, zirconia doped with at least one selected from rare earth elements such as Y and Sc, ceria doped with at least one selected from rare earth elements, and lanthanum gallate doped with at least one selected from Sr and Mg. Formed from at least one of the.

The outer electrode layer 1106 is formed over the entire circumference along the outer peripheral surface of the electrolyte layer 1105, and the lower end is terminated above the lower end of the electrolyte layer 1105 and the upper end is terminated below the upper end of the electrolyte layer 1105. ing. The outer electrode layer 1106 is, for example, a lanthanum manganite doped with at least one selected from Sr and Ca, and a lanthanum ferrite doped with at least one selected from Sr, Co, Ni and Cu, Sr, Fe, Ni and Cu. It is formed from at least one of lantern cobaltite, silver, etc. doped with at least one selected from.

Next, the cap 1102 will be described. Since the cap 1102 attached to the upper end side and the lower end side of the cell body 1101 has the same structure, the cap 1102 attached to the lower end side of the cell body 1101 is specifically described here. To explain.

The cap 1102 (metal cap) is provided so as to surround the upper and lower ends of the cell body 1101, and is electrically connected to the inner electrode layer 1104 of the cell body 1101 as a connection electrode for pulling out the inner electrode layer 1104 to the outside. Function. As shown in FIG. 11, the cap 1102 provided at the lower end of the cell body 1101 has a cylindrical first cylindrical portion 1102a and an annular ring extending outward from the upper end of the first cylindrical portion 1102a. It has a portion 1102b and a second cylindrical portion 1102c extending upward from the outer periphery of the annular portion 1102b. At the center of the first cylindrical portion 1102a of the cap 1102, a fuel gas flow path 1107 communicating with the fuel gas flow path 1103 of the inner electrode layer 1104 is formed. The fuel gas flow path 1107 is an elongated pipeline provided so as to extend in the axial direction of the cell body 1101 from the center of the cap 1102.

The cap 1102 is coated with chromium oxide (Cr ₂ O ₃ in this embodiment) on the inner peripheral surface and the outer peripheral surface of the main body made of ferritic stainless steel or austenitic stainless steel, and further, the outer peripheral surface is MnCo ₂ O. ₄ is coated. In addition, an Ag current collector film is provided on the outer peripheral surface of the coated MnCo ₂ O ₄ layer. In the present embodiment, the Ag current collector film is provided over the entire outer peripheral surface of the cap 1102, but it may be provided only on a part of the outer peripheral surface.

The silver paste 1108 is arranged in the space between the inside of the second cylindrical portion 1102c of the cap 1102 and the outer peripheral surface of the end portion of the inner electrode layer 1104 of the cell body 1101. By firing after assembling the cell 1100, the silver paste 1108 is sintered and the inner electrode layer 1104 and the cap 1102 are electrically and mechanically bonded. Further, a glass seal 1109 made of a glass material is provided between the inner peripheral surface of the second cylindrical portion 1102c of the cap 1102 and the outer peripheral surface of the lower end portion of the electrolyte layer 1105. By this glass seal 1109, the space between the cap 1102 and the inner electrode layer 1104 is airtightly sealed with respect to the space outside the cell 1100.

(Fuel cell stack)
12 (A) and 12 (B) show the fuel cell stack in this embodiment. Regarding the configuration of the cell group arrangement of the fuel cell stack 1100 in FIG. 1 described above, the cell group 1010a, the cell group 1010b, and the cell group 1010a are arranged in this order in the width direction (short side direction) of the fuel cell stack 1100. In FIG. 12A, the cell group 1010a on the right side and the cell group 1010a on the left side are connected to each other in the back of the paper in FIG. Therefore, the manifold 1002b to which the plurality of cells 1001 arranged in the cell group 1010a are connected and fixed has a "U" shape in the top view (FIG. 12 (B)).

The cell 1001 has a cylindrical shape and includes metal caps 1004 electrically connected to both ends of the fuel electrode 1003, and the metal cap 1004 is sealed by the cell 1001 and the glass material 1005 (not shown in FIGS. 11 to 13). ing. The cell 1001 is erected on the manifold 1002b via the insulating support member 1006 (also referred to as a bush), and is airtightly fixed by the glass ring 1007. A part of the cell 1001 is arranged on the other end side of the cell 1001 below the "U" -shaped manifold 1002a via the insulating support member 1006, and is airtightly joined by a glass ring 1007.

The electrical connection between the plurality of cells 1001 is such that the metal cap 1004 and the end of the air electrode 1008 are electrically connected in series via the current collector 1009. Here, considering the current distribution in the cell 1001, it is desirable to install the current collector on the downstream side of the cell 1001 with respect to the flow direction of the fuel gas. Therefore, in the cell group 1010a in which the fuel gas flows from the other end side to the one end side (from the upper end side to the lower end side in FIG. 12A), the current collector 1009 may be provided on the one end side (lower end side). preferable. On the other hand, in the cell group 1010b in which the fuel gas flows in the direction from one end side to the other end side (direction from the lower end side to the upper end side in FIG. 12A), it is preferable to provide the current collector 1009 on the other end side. .. Further, the electrical connection between the cell group 1010a and the cell group 1010b requires a connection between one end side of the cell 1001 arranged in the cell group 1010a and the other end side of the cell 1001 arranged in the cell group 1010b. Since it is necessary to connect by a long-distance current collector extending from the other end to the other end, it is preferable to separate the cells of the cell group 1010a and the cell group 1010b from the viewpoint of preventing a short circuit to the cell 1001.

As shown in FIG. 12B, the fuel gas reformed by the reformer 1011 is supplied from the fuel gas supply pipe 1020 of the “U” -shaped manifold 1002a in the top view, and the “U” -shaped manifold is supplied. The gas flow path of the cell group 1010a on the upstream side, which is dispersed inside the 1002a and is connected so as to communicate with the "U" -shaped manifold 1002a, flows from the other end side to one end side. The fuel gas discharged from the cell group 1010a and unused for power generation is collected in the manifold 1002b and flows through the gas flow path of the cell group 1010b on the downstream side where the other end side is open from one end side to the other end side. It is discharged from the upper end of the cell group 1010b.

Further, as shown in FIG. 12C, the rectangular parallelepiped shape manifold 1002a may be divided into two and arranged on the other end side. By distributing the fuel gas derived from the reformer 1011 and supplying it to the fuel gas supply pipe 1020 of the manifold 2b, the fuel gas can be sequentially supplied from the cell group 1010a to the cell group 1010b on the downstream side. can.

On the other hand, the air for power generation is supplied from below the cell 1001 to the side surface of the plurality of cylindrical cells 1001 erected as the cell group 1010a or the cell group 1010b (dotted line arrow in FIG. 12A). The supplied air for power generation flows from one end side to the other end side of the cell 1001, mixes with the unused gas at the upper end portion of the cell group 1010b on the downstream side where the other end side is open, and is burned.

Here, since it becomes difficult for air for power generation to flow in the gaps between the plurality of cells 1001 constituting the cell group 1010a on the upstream side where the manifold 1002a is installed on the other end side, the air flow on the upstream side is taken into consideration. It is preferable that the cell group 1010a on the downstream side and the cell group 1010b on the downstream side are separated by a predetermined distance.

Further, in the top view, as shown by the dotted arrow in FIG. 12 (D), since it is difficult for air for power generation to flow directly under the region extending in the short side direction of the fuel cell stack in the “U” -shaped manifold 2b, a plurality of them. It is preferable that the air supply hole for supplying the air for power generation to the cell 1001 is installed not only on the long side side of the fuel cell stack but also on the short side side to supply the air for power generation.

The fuel gas passes through the manifold 1002a and is consumed for the power generation reaction in the cell group 1010a on the upstream side. The unused gas that remains unconsumed by the power generation reaction is supplied to the downstream cell group 1010b through the manifold 1002b, and is further consumed by the power generation reaction in the downstream cell group 1010b.

Further, as shown in FIG. 13, a rectangular parallelepiped shape manifold 1002a may be arranged on the other end side of the center of the top view. By distributing the fuel gas derived from the reformer 1011 and supplying the fuel gas to the fuel gas supply pipe 1020 of the manifold 1002a, the fuel gas can be sequentially supplied from the cell group 1010a to the cell group 1010b on the downstream side. can.

As described above, a plurality of cells are configured by allowing fuel gas to flow in from the manifold on the other end side, collecting unused gas in the manifold on the one end side, and supplying it to the cell group on the open side. Conventional fuel by simply adjusting the number of cells on the upstream side and the downstream side without significantly restricting or hindering the arrangement of cells, the electrical series connection between cells, the flow of air for power generation, etc. It is possible to provide a fuel cell stack having a high fuel utilization rate to which the structure of the battery module can be applied as it is.

Further, by arranging the reformer or the evaporator in the combustion region where the off gas discharged from the fuel cell stack is burned, it is possible to apply the same arrangement configuration as the conventional fuel cell module. Therefore, it is possible to support a small fuel cell device having an output performance of about 1 kW, and to provide a highly efficient and highly durable fuel cell system.

1 Fuel cell (cell)
1a Fuel cell 1b Fuel cell 2a (1st) Manifold 2b (2nd) Manifold 2b1 Room 2b2 Room 10a 1st cell stack (cell group)
10b Second cell stack (cell group)
12 Reformer 12A Evaporation part 12B Remodeling part 13A Supply pipe 13B Supply pipe 14 Connection part 18 Burning part 20 minutes Piping 20A Opening 22 Housing 22A Opening 24 Frame body 24A Opening 30 Current collecting member 30a End part Current collecting member 30b End Part Current collecting member 32 Connecting current collecting member 34 Conductive support substrate 34A Gas flow path 36 Fuel side electrode layer 38 Solid electrolyte layer 40 Air side electrode layer 42 Interconnector 44 P-type semiconductor layer 46 Insulation material 50 Housing member 50a Bottom plate 50b Side plate 50c Top plate 50d First opening 50e Second opening 52 First frame 52a Opening 52b Top plate 52c Side plate 54 Second frame 54a Opening 54b Top plate 54c Side plate 56a Glass seal 56b Glass seal 57a Glass seal 57b Glass seal 60 Partition plate 60A Surface 60B Surface 60a Air flow passage 60b Upper through hole 60c Lower through hole 60d Lower end ejection hole 60e First air ejection hole 60f Second air ejection hole 90 Insulation material 92 Inner housing 92a Exhaust exhaust hole 94 Outer housing 96 Exhaust flow path 98 Air flow path 100 Fuel cell cell stack (device)
150 Housing member 150a Bottom plate 150b Side plate 150c Top plate 150c1 First top plate part 150c2 Second top plate part 150c3 Connecting part 150d Opening 150e Opening 1001 Cell 1002a Manifold 1002b Manifold 1003 Fuel pole 1004 Metal cap 1005 Glass material 1006 Insulation Support member 1007 Glass ring 1008 Air electrode 1009 Current collector 1010a Cell group 1010b Cell group 1011 Reformer 1020 Fuel gas supply pipe 1100 Fuel cell cell stack 1101 Cell body 1102 Cap 1102b Circular portion 1103 Fuel gas flow path 1104 Inner electrode layer 1105 Electrolyte layer 1106 Outer electrode layer 1107 Fuel gas flow path 1108 Silver paste 1109 Glass seal

Claims (6)

A first cell stack in which a plurality of columnar fuel cell cells having a gas flow path extending in the longitudinal direction are juxtaposed in the first direction, a cell group in which the second cell stack is juxtaposed in the horizontal direction, and a cell group.
A first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack.
The fuel gas connected to the first cell stack and the second cell stack and discharged from the first cell stack is recovered, and the recovered fuel gas is used as the fuel for each of the second cell stacks. A fuel cell stacking device comprising a second manifold for supplying a battery cell.
The second manifold is provided with a first connection portion to which the first cell stack is connected and a second connection portion to which the second cell stack is connected, and is provided in the second manifold. Is provided with a flow path resistance portion that gives resistance to the flow of fuel gas from the portion provided with the first connection portion to the portion provided with the second connection portion .
The flow path resistance portion is composed of a gap formed in the second manifold so as to extend in the first direction, and the height of the gap is smaller than the height of the space in the first connection portion. , A fuel cell stacking device characterized by that. The height of the gap is smaller than the height of the space in the second connection.
The fuel cell stack device according to claim 1. A first cell stack in which a plurality of columnar fuel cell cells having a gas flow path extending in the longitudinal direction are juxtaposed inside, a cell group in which a second cell stack is juxtaposed in the horizontal direction, and a cell group.
A first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack.
The fuel gas connected to the first cell stack and the second cell stack and discharged from the first cell stack is recovered, and the recovered fuel gas is used as the fuel for each of the second cell stacks. A fuel cell stacking device comprising a second manifold for supplying a battery cell.
The second manifold is provided with a first connection portion to which the first cell stack is connected and a second connection portion to which the second cell stack is connected, and is provided in the second manifold. Is provided with a flow path resistance portion that gives resistance to the flow of fuel gas from the portion provided with the first connection portion to the portion provided with the second connection portion.
The fuel cell stack device is characterized in that the second manifold is configured so that the height of the second connection portion is lower than the height of the first connection portion. The second manifold is
With the first frame body on which the first connection portion is formed,
The second frame body having the same shape as the first frame body and the second frame body in which the second connection portion is formed
The first frame body and the housing member to which the second frame body is fixed to the upper surface are provided.
The second frame is fixed at a position lower than the first frame with respect to the upper surface of the housing member, and the flow path resistance portion is the lower end of the second frame and the housing. The fuel cell stack device according to claim 3 , which is composed of a gap between the bottom surface of the body member and the body member. The second manifold is
With the first frame body on which the first connection portion is formed,
With the second frame body in which the second connection portion was formed,
The first frame body and the housing member to which the second frame body is fixed to the upper surface are provided.
The upper surface of the housing member is configured such that the portion where the second frame is fixed is lower than the portion where the first frame is fixed, and the flow path resistance portion is the portion. The fuel cell stack device according to claim 3 , further comprising a gap between the lower end of the second frame and the bottom surface of the housing member. A first cell stack in which a plurality of columnar fuel cell cells having a gas flow path extending in the longitudinal direction are juxtaposed inside, a cell group in which a second cell stack is juxtaposed in the horizontal direction, and a cell group.
A first manifold connected to the first cell stack and for supplying fuel gas to each fuel cell of the first cell stack.
The fuel gas connected to the first cell stack and the second cell stack and discharged from the first cell stack is recovered, and the recovered fuel gas is used as the fuel for each of the second cell stacks. A fuel cell stacking device comprising a second manifold for supplying a battery cell.
The second manifold is provided with a first connection portion to which the first cell stack is connected and a second connection portion to which the second cell stack is connected, and is provided in the second manifold. Is provided with a flow path resistance portion that gives resistance to the flow of fuel gas from the portion provided with the first connection portion to the portion provided with the second connection portion.
Moreover,
A reformer, which is arranged above the second cell stack, reforms the raw material gas into a fuel gas containing hydrogen, and supplies the fuel gas to the first manifold.
The upper end of the first cell stack is connected to the lower end of the first manifold.
A fuel cell stack device, characterized in that the lower end of the first manifold and the lower end of the reformer are located at the same height.

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