JP2011210411A - Cell stack device, fuel cell module, and fuel cell device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cell stack device improved in current collection efficiency.SOLUTION: In the cell stack device, a current collection member 4 has a plurality of first current collection members 4a of belt shape which are connected to fuel battery cells on one side and extend along the width direction of the fuel battery cell and second current collection members 4b of belt shape which are connected to fuel battery cells on the another side and extend along the width direction of the fuel battery cell in the longitudinal direction of the fuel battery cell, and has a connection part to connect the first current collection members 4a and the second current collection members 4b. The cross-sectional area along the longitudinal direction of the fuel battery cell of the first current collection member 4a and the second current collection member 4b located at the other end part side in the longitudinal direction of the fuel battery cell is larger than the cross-sectional area along the longitudinal direction of the fuel battery cell of the first current collection member 4a and the second current collection member 4b located at one end part side in the longitudinal direction of the fuel battery cell, thereby, the current generated in the cell stack can be collected efficiently and the power generation output performance is improved.

Description

  The present invention relates to a cell stack device, a fuel cell module, and a fuel cell device each including a cell stack in which a plurality of columnar fuel cells are arranged upright and electrically connected.

  In recent years, as next-generation energy, a plurality of columnar fuel cells that can obtain electric power using a reaction gas (fuel gas) and an oxygen-containing gas (usually air) are arranged upright, There have been proposed a fuel cell module in which cell stack devices electrically connected in series are housed in a storage container, and a fuel cell device having a fuel cell module (see, for example, Patent Document 1). .

  The cell stack apparatus includes a plurality of fuel cells each having a gas flow path for flowing a reaction gas therein, one end portion serving as a reaction gas introduction port, and the other end portion serving as a reaction gas discharge port. The cell stack is arranged in a state of being erected via a current collecting member and electrically connected in series.

  Further, as the current collecting member, a plurality of first current collecting pieces connected to one fuel battery cell, a plurality of second current collecting pieces connected to the other fuel battery cell, one end of the first current collecting piece, The first conductive piece for connecting the other end of the second current collecting piece, and the second conductive piece for connecting one end of the second current collecting piece and the other end of the other first current collecting piece, as a basic configuration, There has been proposed a current collecting member configured to be continuously connected in the longitudinal direction of the fuel cell (see, for example, Patent Document 2).

JP 2003-308857 A JP 2009-231168 A

  By the way, when a reaction gas is supplied to one end of the fuel cell to generate power, the fuel cell generates heat when generating power, so that the reaction gas flowing through the gas channel of the fuel cell passes through the gas channel. It is heated while flowing, and the other end side of the fuel cell is heated. Therefore, the temperature on the other end side of the fuel cell becomes higher than the temperature on one end side of the fuel cell, and accordingly, the temperature on the other end side of the current collecting member connected to the fuel cell increases. As a result, the electrical conductivity on the other end side of the current collecting member decreases. Thereby, there exists a possibility that the current collection efficiency by the other end part side of a current collection member may fall.

  Therefore, the present invention provides a cell stack device, a fuel cell module, and a fuel cell device that have improved power generation output performance by including a current collecting member that can suppress a decrease in current collecting efficiency on the other end side of the current collecting member. The purpose is to provide.

The cell stack device of the present invention has a gas flow path for flowing a reaction gas therein, one end of which serves as an introduction port for the reaction gas, and the other end serves as a discharge port for the reaction gas. A cell stack device comprising a cell stack in which a plurality are arranged in a standing state via a current collecting member and electrically connected in series, wherein the current collecting member is one of the fuel cells A band-shaped first current collecting piece connected to the cell and extending along the width direction of the fuel cell, and a band-shaped second current collector connected to the other fuel cell and extending along the width direction of the fuel cell. A plurality of current collecting pieces are provided in the longitudinal direction of the fuel battery cell, and a connecting portion for connecting the first current collecting piece and the second current collecting piece is provided, and the other in the longitudinal direction of the fuel battery cell. The first current collector piece and the second current collector located on the end side The cross-sectional area of the cross section along the arrangement direction of the fuel cells of the piece and from one end to the other end of the fuel cells is located on the one end side in the longitudinal direction of the fuel cells. It is characterized by being larger than the cross-sectional area of the cross section along the arrangement direction of the fuel battery cells of the electric piece and the second current collecting piece and from one end to the other end of the fuel battery cell.

  In such a cell stack device, the current collecting member is connected to one fuel cell, and is connected to the first strip-shaped current collecting piece extending along the width direction of the fuel cell and the other fuel cell. A plurality of strip-shaped second current collecting pieces extending in the width direction of the fuel battery cells in the longitudinal direction of the fuel battery cells, and a connecting portion for connecting the first current collecting pieces and the second current collecting pieces Along the arrangement direction of the fuel cells of the first current collector piece and the second current collector piece located on the other end side in the longitudinal direction of the fuel cell and from one end of the fuel cell to the other end The cross-sectional area of the cross section is along the arrangement direction of the fuel battery cells of the first current collector piece and the second current collector piece located on one end side in the longitudinal direction of the fuel battery cell and from one end of the fuel battery cell Larger than the cross-sectional area of the cross section along the other end Therefore, even when the temperature on the other end side of the current collecting member rises and the conductivity decreases, the generated current can be collected efficiently, and the current collecting on the other end side of the current collecting member Since it can suppress that efficiency falls, it can be set as the cell stack apparatus which the power generation output performance improved.

  In the cell stack device of the present invention, the length of each of the first current collection piece and the second current collection piece in the longitudinal direction of the fuel cell is the same, and each of the first current collection pieces And the width of the second current collecting piece in the arrangement direction of the fuel cells is that the first current collecting piece and the second current collecting piece located on the other end side in the longitudinal direction of the fuel cells. It is preferable that the fuel cell is wider than the first current collection piece and the second current collection piece located on one end side in the longitudinal direction of the fuel cell.

  In such a cell stack device, the lengths of the first current collecting piece and the second current collecting piece in the longitudinal direction of the fuel cells are the same, and the first current collecting piece and the second current collecting piece are the same. The width of the fuel cells in the arrangement direction of the fuel cells is such that the first current collecting piece and the second current collecting piece located on the other end side in the longitudinal direction of the fuel cells are on the one end side in the longitudinal direction of the fuel cells. Since it is wider than the first current collecting piece and the second current collecting piece located at the same position, even when the temperature on the other end side of the current collecting member rises, the generated current can be collected efficiently. It can suppress that the current collection efficiency by the other end part side of a current collection member falls.

  In the cell stack device of the present invention, the connection portion includes a first connection portion in a band shape that connects one end of the first current collection piece and the other end of the second current collection piece, and the first current collection device. A strip-shaped second connecting portion that connects the other end of the piece and one end of the second current collecting piece, and the current collecting member includes the first current collecting piece, the first connecting portion, and the second current collecting member. A plurality of electrical pieces and the second connection portion are arranged in this order in the longitudinal direction of the fuel cell, and the lengths of the connection portions in the longitudinal direction of the fuel cell are the same, and The width of the connecting portion in the arrangement direction of the fuel cells is located on the other end side in the longitudinal direction of the fuel cells, and the connecting portion is located on one end portion in the longitudinal direction of the fuel cells. It is preferable that it is wider than the said connection part.

In such a cell stack device, the current collecting member is formed by arranging a plurality of first current collecting pieces, first connecting portions, second current collecting pieces and second connecting portions in this order in the longitudinal direction of the fuel cell. In addition, the lengths of the fuel cells in the longitudinal direction of each connection portion are the same, and the width in the arrangement direction of the fuel cells of each connection portion is located on the other end side in the longitudinal direction of the fuel cells. Since the connecting portion is wider than the connecting portion located on one end side in the longitudinal direction of the fuel cell, the temperature of the connecting portion located on the other end side in the longitudinal direction of the fuel cell rises and the conductivity Even when the voltage drops, the connecting part can efficiently flow current, and the current collecting efficiency on the other end side of the current collecting member can be prevented from being lowered.

  Further, in the cell stack device of the present invention, the connection portion includes a strip-shaped first connection portion that connects one end of the plurality of first current collection pieces and one end of the plurality of second current collection pieces, A belt-like second connecting portion that connects the other end of the first current collecting piece and the other end of the plurality of second current collecting pieces, and the current collecting member serves as one unit for the fuel cell. A plurality of adjacent units are joined to each other in the longitudinal direction of the cell via conductive connecting pieces, and the length of each of the connecting portions in the longitudinal direction of the fuel cell is the same. The length of each of the connecting portions in the arrangement direction of the fuel cells is such that the connecting portion located on the other end side in the longitudinal direction of the fuel cells is on one end side in the longitudinal direction of the fuel cells. It is preferable that it is longer than the said connection part located in

  In such a cell stack device, the connecting portion includes a first connecting portion that connects one end of the plurality of first current collecting pieces and one end of the plurality of second current collecting pieces, and a plurality of first current collecting pieces. A second connecting portion that connects the other end and the other ends of the plurality of second current collecting pieces, and the current collecting member includes a plurality of the current collecting members in the longitudinal direction of the fuel cell as one unit. And the length of each connecting portion in the longitudinal direction of the fuel cells, and the length of each connecting portion in the arrangement direction of the fuel cells, Since the connecting portion located on the other end side in the longitudinal direction of the fuel cell is thicker than the connecting portion located on one end side in the longitudinal direction of the fuel cell, the other end side in the longitudinal direction of the fuel cell The temperature of the connection located at Even when the connecting portion is able to flow efficiently current collecting efficiency of the other end of the current collecting member it can be prevented from being lowered.

  The fuel cell module of the present invention is characterized in that the above-described cell stack device is housed in a housing container, so that a fuel cell module with improved power generation output performance can be obtained.

  The fuel cell device according to the present invention is characterized in that the fuel cell module and an auxiliary machine for operating the fuel cell module are housed in an outer case, so that the fuel cell device with improved power generation output performance is provided. It can be.

In the cell stack device of the present invention, the current collecting member is connected to one of the fuel cells, and is connected to the first current collecting strip in the belt shape extending along the width direction of the fuel cells, and the other fuel cell. A plurality of strip-shaped second current collecting pieces extending in the width direction of the fuel battery cell are provided in the longitudinal direction of the fuel battery cell, and a connecting portion for connecting the first current collecting piece and the second current collecting piece is provided. And along the arrangement direction of the fuel cells of the first current collector piece and the second current collector piece located on the other end side in the longitudinal direction of the fuel cell, and from one end of the fuel cell to the other end The cross-sectional area of the cross section is different from one end of the fuel cell along the arrangement direction of the fuel cell of the first current collector piece and the second current collector piece located on one end side in the longitudinal direction of the fuel cell. Because it is larger than the cross-sectional area of the cross section along the edge Even when the temperature on the other end side of the current collecting member rises and the conductivity decreases, the generated current can be collected efficiently, and the current collecting efficiency on the other end side of the current collecting member decreases. Therefore, the cell stack device with improved power generation output performance can be obtained. Further, by storing the cell stack device in the storage container, a fuel cell module with improved power generation output performance can be obtained, and further, the fuel cell module and an auxiliary device for operating the fuel cell module are installed on the exterior. By storing in the case, a fuel cell device with improved power generation output performance can be obtained.

1 shows an example of a cell stack device of the present invention, (a) is a side view schematically showing the cell stack device, and (b) is an enlarged view of a part surrounded by a dotted frame of the cell stack device of (a). FIG. The current collecting member in FIG. 1 is shown, (a) is a perspective view, (b) is a plan view showing an enlarged part of a portion surrounded by a dotted frame on the other end side of the current collecting member in (a), (C) is a top view which expands and shows a part of part enclosed with the dotted-line frame in the other end part side of the current collection member of (a). The current collection member which constitutes another example of the cell stack device of the present invention is shown, (a) is a perspective view, (b) is the part enclosed with the dotted line frame in the other end side of the current collection member of (a). The top view which expands and shows a part, (c) is a top view which expands and shows a part of part enclosed with the dotted-line frame in the one end part side of the current collection member of (a). (A) is a top view by the side of the other end part of the current collection member which comprises further another example of the cell stack apparatus of this invention, (b) is another example of the cell stack apparatus of this invention. It is a top view of the other end part side of the current collection member which constitutes. It is an external appearance perspective view which shows an example of the fuel cell module of this invention. It is a disassembled perspective view which shows an example of the fuel cell apparatus of this invention.

  1A and 1B show an example of a cell stack device 1 according to the present invention. FIG. 1A is a side view schematically showing the cell stack device 1, and FIG. 1B is a diagram of the cell stack device 1 of FIG. It is the top view which expanded the part, and has shown and extracted the part enclosed with the dotted-line frame shown to (a). The same members are assigned the same numbers, and so on. In addition, in (b), in order to clarify, the part corresponding to the part enclosed with the dotted-line frame shown by (a) is shown with the arrow.

  Here, the cell stack device 1 is provided as an inner electrode layer on a flat surface on one side of a columnar conductive support 12 having a pair of opposed flat surfaces (hereinafter sometimes abbreviated as support 12). A plurality of columnar (hollow flat plate) fuel cells 3 formed by sequentially stacking a fuel electrode layer 8, a solid electrolyte layer 9, and an air electrode layer 10 as an outer electrode layer are connected to each fuel cell 3. The cell stacks 2 are arranged in a state where they are erected via the current collecting members 4 and are electrically connected in series to form the cell stack 2. The cell stack 2 is arranged in the arrangement direction of the fuel cells 3 (hereinafter referred to as cell arrangement). A manifold 7 that supplies fuel gas to the fuel cell 3 at one end (lower end) of the fuel cell 3. It is fixed and configured.

  Further, an interconnector 11 is provided on the other flat surface of the fuel cell 3 and penetrates from one end (lower end) to the other end (upper end) of the fuel cell 3 in the support 12. A plurality of gas flow paths 13 for flowing fuel gas (reactive gas) are provided at predetermined intervals. The fuel cell 3 generates electric power by flowing fuel gas through the fuel cell 3 (gas flow path 13) and flowing oxygen-containing gas (air) outside the fuel cell 3. In addition, by burning the fuel gas that has not been used for power generation on the other end side (upper end side) of the fuel battery cell 3, the cell stack device 1 can be warmed, and an efficient operation can be performed. it can.

In addition, the fuel cell 3 generates electric power at a portion where the fuel electrode layer 8, the solid electrolyte layer 9, and the air electrode layer 10 are laminated in this order. In the following description, unless otherwise specified, the inner electrode layer will be described as the fuel electrode layer 8 and the outer electrode layer will be described as the air electrode layer 10, and the cell stack device 1 is connected to the upper end side of the fuel cell 3 ( In the upper part, the fuel gas that has not been used for power generation is burned.

  Further, the P-type semiconductor layer 14 can be provided on the outer surface (upper surface) of the interconnector 11, and FIG. 1 shows an example in which the P-type semiconductor layer 14 is provided. By connecting the current collecting member 4 to the interconnector 11 via the P-type semiconductor layer 14, the connection between the two becomes an ohmic connection, the potential drop can be reduced, and a reduction in current collecting efficiency can be effectively avoided. Become.

  Alternatively, the fuel cell 3 may be configured by using the support 12 also as the fuel electrode layer 8 and sequentially laminating the solid electrolyte layer 9 and the air electrode layer 10 on one surface thereof.

  Various fuel cells are known as the fuel cell 3 in the present invention. However, in order to obtain a fuel cell 3 with good power generation performance, the fuel cell 3 can be a solid oxide fuel cell 3. Accordingly, the fuel cell device can be reduced in size with respect to unit power, and a load following operation that follows a fluctuating load required for a household fuel cell can be performed.

  Below, each member which comprises the cell stack apparatus 1 shown in FIG. 1 is demonstrated.

As the fuel electrode layer (inner electrode layer) 8, generally known ones can be used, and porous conductive ceramics, for example, ZrO ₂ (stabilized) in which rare earth elements such as Y and Yb are dissolved. Zirconia) and Ni and / or NiO.

In the fuel electrode layer 8, at least one of Ni and NiO and the content of ZrO ₂ in which the rare earth element is in solid solution are such that the volume ratio after calcination-reduction is ZrO in which NiO: rare earth element is in solid solution. ₂ (for example, NiO: YSZ) is preferably in the range of 35:65 to 65:35. Further, the porosity of the fuel electrode layer 8 is preferably 15% or more, particularly preferably in the range of 20 to 40%, and the thickness thereof is preferably 1 to 30 μm.

The solid electrolyte layer 9 has a function as an electrolyte that bridges electrons between the electrodes and is required to have a gas barrier property in order to prevent leakage between the fuel gas and the oxygen-containing gas. It is formed from ZrO ₂ in which ₃ to 15 mol% of a rare earth element is dissolved. In addition, as long as it has the said characteristic, you may form using another material etc.

  Further, the solid electrolyte layer 9 is desirably a dense material having a relative density (according to Archimedes method) of 93% or more, particularly 95% or more in terms of preventing gas permeation, and a thickness of 5 to 50 μm. Preferably there is.

The air electrode layer (outer electrode layer) 10 can be formed from conductive ceramics (for example, ABO ₃ type perovskite oxide) and needs to have gas permeability, so the porosity is 20% or more. In particular, it is preferably in the range of 30 to 50%. Furthermore, the thickness of the air electrode layer 10 is preferably 30 to 100 μm from the viewpoint of current collection.

Although the interconnector 11 can be formed from conductive ceramics, it needs to have reduction resistance and oxidation resistance because it comes in contact with a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air, etc.). Therefore, a lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) is preferably used. The interconnector 11 is dense in order to prevent leakage of the fuel gas flowing through the plurality of fuel gas passages 13 formed in the conductive support 12 and the oxygen-containing gas flowing outside the conductive support 12. It has to have a relative density of 93% or more, in particular 95% or more.

  Further, the thickness of the interconnector 11 is preferably 10 to 50 μm for the purpose of preventing gas leakage and suppressing an increase in electrical resistance. If the thickness is smaller than this range, gas leakage is liable to occur. If the thickness is larger than this range, the electric resistance is large, and the current collecting function may be lowered due to a potential drop.

  The support 12 is required to be gas permeable in order to allow the fuel gas to permeate to the fuel electrode layer 8 and to be conductive in order to collect current via the interconnector 11. Therefore, as the support 12, it is necessary to adopt a material satisfying such a requirement as a material, and for example, conductive ceramics, cermet, or the like can be used.

  In addition, the support 12 preferably has an open porosity of 30% or more, particularly 35 to 50% in order to have the required gas permeability, and its conductivity is 50 S / cm or more, more It is preferably 300 S / cm or more, particularly preferably 440 S / cm or more.

An example of the P-type semiconductor layer 14 is a layer made of a transition metal perovskite oxide. Specifically, a material having higher electron conductivity than a lanthanum chromite-based perovskite oxide (LaCrO ₃ -based oxide) constituting the interconnector 11, for example, LaMnO in which Mn, Fe, Co, etc. are present at the B site. P-type semiconductor ceramics made of at least one of _three- based oxides, LaFeO ₃ -based oxides, LaCoO ₃ -based oxides and the like can be used. In general, the thickness of the P-type semiconductor layer 15 is preferably in the range of 30 to 100 μm.

  Each fuel battery cell 3 is electrically connected in series via a current collecting member 4 to constitute a cell stack 2. In addition, although mentioned later in detail, the current collection member 4 can be comprised with the member which consists of a metal or alloy which has elasticity.

  The cell stack 2 configured as described above is sandwiched by the conductive member 5 from both ends in the cell arrangement direction via the current collecting member 4, and these are connected to the fuel cell 3 and the lower end side of the conductive member 5 as the fuel cell. 3 is fixed to a manifold 7 for supplying fuel gas to the cell stack device 1.

  The manifold 7 has a shape in which an upper portion is opened to supply fuel gas to each fuel cell 3, and the cell stack 2 is disposed inside the opening using a predetermined jig, and a seal such as glass is provided. Gas seal with material. Thereby, it can suppress that the fuel gas supplied into the inside of the fuel cell 3 leaks. In addition, the material which comprises the manifold 7 can use the material similar to the current collection member 4 mentioned later.

  The conductive member 5 has a flat plate portion (not shown) opposed to the fuel cell 3 disposed at the end of the cell stack 2 and a shape extending outward along the cell arrangement direction. A current extraction unit 6 for extracting a current generated by the power generation of the fuel cell 3) is provided, and the current generated by the cell stack 2 can be taken out from the current extraction unit 6. In addition, the material which comprises the electrically-conductive member 5 can use the same material as the material of the current collection member 4 mentioned later.

  Here, the current collection member 4 which comprises the cell stack apparatus 1 of this invention is demonstrated.

2 shows the current collecting member in FIG. 1, (a) is a perspective view, and (b) is a part enclosed by a dotted line frame on the other end side (upper end side) of the current collecting member in (a). The top view which expands and shows a part, (c) is a top view which expands and shows a part of part enclosed with the dotted-line frame in the one end part side (lower end part side) of the current collection member of (a). In addition, in (b) and (c), the part corresponding to the part enclosed by the dotted line frame shown in (a) is indicated by an arrow for clarity.

  The current collecting member 4 is connected to one adjacent fuel battery cell 3 and extends in the width direction of the fuel battery cell 3 (hereinafter sometimes abbreviated as the cell width direction). And a strip-shaped second current collecting piece 4b connected to one adjacent fuel cell 3 and extending along the cell width direction, one end of the first current collecting piece 4a and the other end of the second current collecting piece 4b And a second connection portion 4d for connecting the other end of the first current collecting piece 4a and one end of the second current collecting piece 4b, and the first current collecting piece 4a, A plurality of first connecting portions 4c, second current collecting pieces 4b, and second connecting portions 4d are arranged in this order in the longitudinal direction of the fuel cell 3 (hereinafter sometimes abbreviated as the cell longitudinal direction). .

  In addition to being exposed to an oxidizing atmosphere, the current collecting member 4 is preferably formed of an alloy containing Cr because it is exposed to a high temperature, and Cr contained in the alloy diffuses out of the alloy. In order to suppress this, it is preferable to apply a coating or the like that suppresses the diffusion of Cr. It is also preferable to produce the conductive member 5 and the manifold 7 from an alloy containing Cr. As the alloy containing Cr, an alloy such as ferritic stainless steel or SUS can be used.

  The first current collecting piece 4a of the current collecting member 4 is connected to the air electrode layer 10 of one adjacent fuel cell 3 and the second current collecting piece 4b is the three interconnectors of the other adjacent fuel cell. 11 (P-type semiconductor layer 14). In order to collect current efficiently, the width of the current collecting member 4 in the cell width direction is preferably about the same as that of the air electrode layer 10, and the length of the current collecting member 4 in the cell longitudinal direction is preferably about the same as that of the air electrode layer 10. .

  Here, when the lower end portion of the fuel cell 3 is fixed to the manifold 7 and fuel gas is supplied to the lower end portion of the fuel cell 3 to generate power, the fuel cell 3 generates heat when generating power. The fuel gas flowing through the gas flow path 13 of the fuel cell 3 is heated while flowing through the gas flow path 13, the upper end side of the fuel battery cell 3 is heated, and the temperature on the upper end side is compared with the temperature on the lower end side. May be expensive. Accordingly, the temperature on the upper end side of the current collecting member 4 connected to the fuel cell 3 is increased, and as a result, the alloy containing Cr constituting the current collecting member 4 particularly on the upper end side of the current collecting member 4. As a result, the current collection efficiency of the cell stack device 1 may be reduced, and the power generation performance of the cell stack device 1 may be reduced. Furthermore, when fuel gas that has not been used for power generation is burned above the fuel cell 3, the temperature on the upper end side of the fuel cell 3 may further be higher than the temperature on the lower end side. .

  Therefore, in the current collecting member 4 shown in FIG. 2, the fuel cell is arranged along the cell arrangement direction of the first current collecting piece 4a and the second current collecting piece 4b arranged on the upper end side of the current collecting member 4. The cross-sectional area of the cross section from one end to the other end of the cell 3 is along the cell arrangement direction of the first current collecting piece 4a and the second current collecting piece 4b disposed on the lower end side of the current collecting member, and the fuel The battery cell 3 has a configuration that is larger than the cross-sectional area of the cross section taken from one end to the other end of the battery cell 3. Specifically, the width in the cell arrangement direction of the first current collecting piece 4a and the second current collecting piece 4b arranged on the upper end side of the current collecting member 4 is the first width arranged on the lower end side of the current collecting member. It is wider than the width of the first current collecting piece 4a and the second current collecting piece 4b in the cell arrangement direction.

Thereby, the cross section along the cell arrangement direction of the 1st current collection piece 4a and the 2nd current collection piece 4b arrange | positioned at the upper end part side of the current collection member 4, and from one end of the fuel cell 3 cell to the other end Of the first current collecting piece 4a and the second current collecting piece 4b arranged on the lower end side of the current collecting member 4 and from one end of the fuel cell 3 to the other end. Therefore, even when the temperature on the upper end side of the current collecting member 4 rises and the conductivity on the upper end side decreases, the fuel cell 3 generates power. Since the current easily flows in the cell width direction through the first current collecting piece 4a and the second current collecting piece 4b, the generated current can be collected efficiently, and the current collecting on the upper end side of the current collecting member 4 can be performed. It can suppress that efficiency falls. Therefore, the cell stack device 1 with improved power generation output performance can be obtained.

  Such a current collecting member 4 can be easily manufactured by punching a plate member manufactured to have a different thickness when the alloy is rolled by rolling into a predetermined shape by pressing and bending the punched member. it can. Moreover, after producing the 1st current collection piece 4a and the 2nd current collection piece 4b of the current collection member 4 by the board from which thickness differs, respectively, it can also produce by joining by welding etc. In addition, after punching a single plate member having a uniform thickness into a predetermined shape by pressing, the first current collecting piece 4a and the second current collecting piece 4b whose width in the cell arrangement direction is desired to be widened are first collected. It can also be produced by joining plate members having the same shape as the electric piece 4a and the second current collecting piece 4b.

  In addition, the upper end part side of the current collection member 4 shows the area | region containing the upper end of the current collection member 4, and it is set as 1/3 area | region from the upper end of the current collection member 4 in the cell stack apparatus 1 of this invention. be able to. Moreover, the lower end part side of the current collection member 4 shows the area | region containing the lower end of the current collection member 4, and it is set as 1/3 area | region from the lower end of the current collection member 4 in the cell stack apparatus 1 of this invention. be able to. In addition, what is necessary is just to set suitably according to the structure of a cell stack apparatus, respectively.

  Here, since the cell stack 2 is formed by arranging a plurality of fuel cells 3 via the current collecting members 4, the fuel cells 3 located on the center side in the cell arrangement direction are arranged at both ends in the cell arrangement direction. Since the number of fuel cells 3 adjacent to each other is larger than the number of fuel cells 3 located on the part side, the temperature on the center side in the cell arrangement direction is higher than the temperature on both ends in the cell arrangement direction. There is a case.

  Therefore, the temperature of the fuel cell 3 arranged on the center side in the cell arrangement direction (particularly the temperature on the upper end side in the cell longitudinal direction) becomes high, and the fuel cell 3 arranged on the center side in the cell arrangement direction. The temperature of the current collecting member 4 connected to the temperature increases, and as a result, the electrical conductivity of the current collecting member 4 decreases, so that the current collecting efficiency of the current collecting member 4 may decrease.

  Therefore, in the cell stack device 1 of the present invention, the cell arrangement of the first current collecting pieces 4a and the second current collecting pieces 4b arranged on the upper end side of the current collecting members 4 arranged on the center side in the cell arrangement direction. The width in the direction is wider than the width in the cell arrangement direction of the first current collecting piece 4a and the second current collecting piece 4b arranged on the upper end side of the current collecting member 4 arranged on both end sides in the cell arranging direction. Thus, even when the conductivity of the current collecting member 4 arranged on the center side in the cell arrangement direction is lowered, the conductivity of the current collecting member 4 arranged on both end sides in the cell arrangement direction is reduced. Since the current generated by the battery cell 3 easily flows in the cell width direction through the first current collecting piece 4a and the second current collecting piece 4b, the generated current can be collected efficiently, and the current collecting member 4 It can suppress that the current collection efficiency of the upper end part side fallsTherefore, the cell stack device 1 with improved power generation output performance can be obtained.

  3A and 3B show a current collecting member constituting another example of the cell stack device of the present invention, wherein FIG. 3A is a perspective view, and FIG. 3B is surrounded by a dotted line frame on the upper end side of the current collecting member of FIG. FIG. 5C is a plan view showing a part of the portion enlarging, and FIG. 8C is a plan view showing a part of the part surrounded by a dotted frame on the lower end side of the current collecting member of FIG. In addition, in (b) and (c), the part corresponding to the part enclosed by the dotted line frame shown in (a) is indicated by an arrow for clarity.

The current collecting member 15 is connected to one adjacent fuel cell 3 and is connected to the first strip-shaped current collecting piece 15a extending along the cell width direction and one adjacent fuel cell 3 to the cell width direction. A strip-shaped second current collecting piece 15b extending along the first connecting portion 15c, one end of the plurality of first current collecting pieces 15a and one end of the plurality of second current collecting pieces 15b, and a plurality of first current collecting pieces 15b. It has the 2nd connection part 15d which connects the other end of the current collection piece 15a, and the other end of several 2nd current collection piece 15b, These are made into 1 unit (not shown), and the longitudinal direction of the fuel cell 3 There are a plurality of adjacent units in the direction, and adjacent units are joined via the conductive connecting piece 15e.

  And the current collection member 15 is along the cell arrangement direction of the 1st current collection piece 15a located in the upper end part side of the current collection member 15, and the 2nd current collection piece 15b, and the other end from the one end of the fuel cell 3 The cross-sectional area of the cross section along the line is larger than the cross-sectional area along the cell distribution direction of the first current collecting piece 15a and the second current collecting piece 15b located on the lower end side of the current collecting member 15. . Specifically, the length of the first current collecting piece 15 a and the second current collecting piece 15 b located on the upper end side of the current collecting member 15 in the cell arrangement direction is the first length located on the lower end side of the current collecting member 15. It is longer than the length of the first current collecting piece 15a and the second current collecting piece 15b in the cell arrangement direction.

  Thereby, even when the temperature on the upper end side of the current collecting member 15 is increased and the conductivity on the upper end side is decreased, the current generated by the cell stack device 1 is converted into the first current collecting piece 15a and the second current collecting piece 15a. Since it becomes easy to flow through the electric strip 15b in the cell width direction, it is possible to efficiently collect the generated current, and it is possible to suppress a decrease in the current collecting efficiency on the upper end side of the current collecting member 15. Therefore, the cell stack device 1 with improved power generation output performance can be obtained.

  The current collecting member 15 can be manufactured by the same method as the current collecting member 4.

  In FIG. 3, three first current collecting pieces 15a and three second current collecting pieces 15b are connected to the first connecting portion 15c and the second connecting portion 15d to constitute one unit. Although an example has been shown, the number of the first current collecting pieces 15a and the second current collecting pieces 15b constituting one unit may be appropriately set according to the configuration of the cell stack device 1. Further, in FIG. 3, an example of the current collecting piece 15 including four units is shown, but the number of units constituting the current collecting member 15 may be set as appropriate according to the configuration of the cell stack device 1.

  4A is a plan view on the upper end side of the current collecting member 16 constituting still another example of the cell stack apparatus of the present invention, and FIG. 4B is still another example of the cell stack apparatus of the present invention. It is a top view in the upper end part side of the current collection member 17 which comprises an example.

  The current collecting member 16 shown in FIG. 4A is a cell in the first current collecting piece 16a and the second current collecting piece 16b, the first connecting part 16c and the second connecting part 16d, which are arranged on the upper end side. The width | variety in the cell arrangement direction of the site | part 16e extended along the width direction is large, and the other structure is the same as the current collection member 4 shown in FIG.

  Here, when the cell stack device 1 is operated, each fuel cell 3 may be deformed. Such deformation of the fuel cell 3 may be a warp that is warped along the cell arrangement direction (hereinafter sometimes referred to as warp), or a deformation that extends in the vertical direction (hereinafter referred to as stretch). .) Is exemplified.

  Further, since the lower end portion of the fuel cell 3 is fixed to the manifold 7 in the cell stack device 1, the deformation of the fuel cell 3 becomes large on the upper end side of the fuel cell 3, and the current collecting member 16 and the fuel The battery cell 3 may be peeled off and the current collection efficiency may be reduced on the upper end side of the current collection member 16.

The current collecting member 16 shown in FIG. 4A is arranged in the cell width direction at the first current collecting piece 16a and the second current collecting piece 16b, the first connecting part 16c and the second connecting part 16d, which are arranged on the upper end side. Since the width in the cell arrangement direction of the portion 16e extending along the line is widened, the first current collecting piece 16a and the second current collecting piece can be obtained without increasing the width in the cell width direction of the portion where the connection portion bends. 16b, the first connecting portion 16c and the second connecting portion 16d can be widened in the cell arrangement direction at the portion extending along the cell width direction without increasing the rigidity on the upper end side of the current collecting member 16. The current collection efficiency on the upper end side of the current collection member 16 can be improved. Therefore, separation between the current collecting member 4 and the fuel battery cell 3 can be suppressed, current can be collected efficiently, and the cell stack device 1 with improved power generation output performance can be obtained.

  A current collecting member 17 shown in FIG. 4 (b) is disposed on the upper end side, a portion 17e of the first current collecting piece 17a and the second current collecting piece 17b that comes into contact with the fuel cell 3 and the first connection. The lengths of the portion 17c and the second connection portion 17d in the cell arrangement direction are longer, and the other configurations are the same as those of the current collecting member 15 shown in FIG.

  The current collecting member 17 shown in FIG. 4B has the first current collecting piece 17a and the second current collecting piece 17b without increasing the length of the portion that does not contact the fuel cell 3 (the portion to bend). Since the length of the portion 17e, the first connecting portion 17c, and the second connecting portion 17d of the first current collecting piece 17a and the second current collecting piece 17b that are in contact with the fuel cells is increased in the cell arrangement direction. The current collection efficiency on the upper end side of the current collecting member 16 can be improved without increasing the rigidity of the member 16. Therefore, separation between the current collecting member 4 and the fuel battery cell 3 can be suppressed, current can be collected efficiently, and the cell stack device 1 with improved power generation output performance can be obtained.

  In the above description, the example in which the length of the first connecting portion 17c and the second connecting portion 17d in the cell arrangement direction in plan view is increased is shown. However, the cells of the first connecting portion 17c and the second connecting portion 17d are shown. The length in the longitudinal direction may be increased. Even in that case, the cross-sectional areas of the first connection portion 17c and the second connection portion 17d along the cell arrangement direction on the upper end side of the current collection member 17 can be increased, and the rigidity of the current collection member 17 is increased. Therefore, the current collection efficiency can be improved, and a cell stack device with improved power generation output performance can be obtained.

  The current collecting members 16 and 17 can be easily manufactured by pressing a plate having a uniform thickness, bending the plate, and then cutting the portion to be thinned by a process such as polishing. Moreover, it can also produce by joining a member to the site | part which wants to lengthen the length of a cell arrangement direction in planar view.

  FIG. 5 is an external perspective view showing an example of the fuel cell module 20 of the present invention. The cell stack device 1 of the present invention is housed in a rectangular parallelepiped storage container 21.

  In order to obtain fuel gas used in the fuel cell 3, a reformer 22 for reforming raw fuel such as natural gas or kerosene to generate fuel gas is disposed above the cell stack 2. ing. The fuel gas generated by the reformer 22 is supplied to the manifold 7 via the gas flow pipe 23, and a gas flow path (not shown) provided inside the fuel battery cell 3 via the manifold 7. To be supplied.

  FIG. 5 shows a state in which a part (front and rear surfaces) of the storage container 21 is removed and the cell stack device 1 and the reformer 22 housed inside are taken out rearward. Here, in the fuel cell module 20 shown in FIG. 5, the cell stack device 1 can be slid and stored in the storage container 21.

In addition, the oxygen-containing gas introduction member 24 provided inside the storage container 21 is disposed between the cell stacks 2 juxtaposed to the manifold 7 in FIG. 5, and the oxygen-containing gas matches the flow of the fuel gas. Thus, the oxygen-containing gas is supplied to the lower end side of the fuel cell 3 so that the fuel cell 3 flows from the lower end side toward the upper end side. The surplus fuel gas discharged from the gas flow path of the fuel cell 3 is burned on the upper end side of the fuel cell 3, whereby the temperature of the fuel cell 3 can be raised, and the cell stack device 1 Can be started earlier. Further, the reformer 22 disposed above the cell stack 2 is warmed by burning the fuel gas discharged from the fuel gas flow path of the fuel battery cell 3 on the upper end side of the fuel battery cell 3. Can do. Thereby, the reforming reaction can be efficiently performed in the reformer 22.

  In such a fuel cell module 20, as described above, the cell stack device 1 with improved power generation output performance is housed in the storage container 21, so that the fuel cell module 20 with improved power generation output performance can do.

  FIG. 6 shows an example of the fuel cell device of the present invention in which the fuel cell module 20 shown in FIG. 5 and an auxiliary machine (not shown) for operating the fuel cell module 20 are housed in an outer case. It is a disassembled perspective view shown. In FIG. 6, a part of the configuration is omitted.

  The fuel cell device 25 shown in FIG. 6 has a module housing chamber 29 in which an inside of an exterior case composed of a support column 26 and an exterior plate 27 is vertically divided by a partition plate 28 and the upper side thereof houses the above-described fuel cell module 20. The lower side is configured as an auxiliary equipment storage chamber 30 for storing auxiliary equipment for operating the fuel cell module 20. In addition, the auxiliary machine accommodated in the auxiliary machine storage chamber 30 is abbreviate | omitted and shown.

  Further, the partition plate 28 is provided with an air circulation port 31 for flowing the air in the auxiliary machine storage chamber 30 to the module storage chamber 29 side, and a part of the exterior plate 27 constituting the module storage chamber 29 An exhaust port 32 for exhausting air in the module storage chamber 29 is provided.

  In such a fuel cell device 25, as described above, the fuel cell module 20 with improved power generation output performance is stored in the module storage chamber 29, and an auxiliary machine for operating the fuel cell module 20 is provided in the auxiliary device storage chamber. By being housed in 30, the fuel cell device 25 with improved power generation output performance can be obtained.

  Although the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and improvements can be made without departing from the scope of the present invention.

  For example, in the cell stack device 1 described above, an example in which the fuel gas is supplied to the gas flow path 13 in the fuel cell 3 and the oxygen-containing gas is supplied to the outside of the fuel cell 3 is shown. The oxygen-containing gas may be supplied to the passage 13 and the fuel gas may be supplied to the outside of the fuel cell 3. In that case, what is necessary is just to set it as the fuel cell 3 of the structure which makes an inner side electrode layer the air electrode layer 10, and makes an outer side electrode layer the fuel electrode layer 8. FIG.

  Further, each corner portion of each member located on the upper end side of the current collecting member may be chamfered such as C chamfering or R chamfering. Thereby, it can suppress that each member located in the upper end part side of a current collection member is exposed to high-temperature oxidation conditions, and abnormal oxidation generate | occur | produces.

Further, as a method of increasing the cross-sectional area along the cell longitudinal direction of the first current collecting piece, the second current collecting piece, the first connecting part and the second connecting part on the upper end side of the current collecting member, Although the structure which lengthens length was shown, you may lengthen the length in the cell longitudinal direction of a 1st current collection piece, a 2nd current collection piece, a 1st connection part, and a 2nd connection part. Even in this case, the first current collecting piece, the second current collecting piece, the first connecting portion and the second connecting portion can be increased, and the current collecting efficiency on the upper end side of the current collecting member can be improved.

  Furthermore, in the cell longitudinal direction and the cell arrangement direction, according to the temperature distribution, along the cell arrangement direction of the first current collection piece and the second current collection piece for each region, and from one end of the fuel cell 3 to the other end. The cross-sectional area of the cross section may be changed stepwise or gradually.

1: Cell stack device 2: Cell stack 3: Fuel cell 4, 15, 16, 17: Current collecting members 4a, 15a, 16a, 17a: First current collecting pieces 4a, 15a, 16a, 17a: Second current collecting Piece 4a, 15a, 16a, 17a: 1st connection part 4a, 15a, 16a, 17a: 2nd connection part 4e: Conductive connection piece 5: Conductive member 6: Current extraction part 7: Manifold 20: Fuel cell module 25: Fuel cell device

Claims (6)

A current collecting member having a plurality of fuel cells each having a gas flow path for flowing a reaction gas therein, one end serving as the reaction gas introduction port, and the other end serving as the reaction gas discharge port A cell stack device comprising cell stacks arranged in an upright state and electrically connected in series,
The current collecting member is connected to one of the fuel battery cells, and is connected to the first current collecting strip in the width direction of the fuel battery cell and the other fuel battery cell, and the fuel battery cell A plurality of strip-shaped second current collecting pieces extending in the width direction of the fuel cell, and a connecting portion for connecting the first current collecting piece and the second current collecting piece. Become
The first current collecting piece and the second current collecting piece located on the other end side in the longitudinal direction of the fuel battery cell along the arrangement direction of the fuel battery cells, and from one end of the fuel battery cell to the other end The cross-sectional area of the cross section extending along the direction of the fuel cell along the arrangement direction of the fuel cells of the first current collector piece and the second current collector piece located on one end side in the longitudinal direction of the fuel cell, and A cell stack device characterized by being larger than a cross-sectional area of a cross section taken from one end to the other end of a fuel cell.   The length of each of the first current collecting piece and the second current collecting piece in the longitudinal direction of the fuel cell is the same, and the fuel of each of the first current collecting piece and the second current collecting piece The first current collecting piece and the second current collecting piece whose width in the arrangement direction of the battery cells is located on the other end side in the longitudinal direction of the fuel battery cell are one end in the longitudinal direction of the fuel battery cell. The cell stack device according to claim 1, wherein the cell stack device is wider than the first current collecting piece and the second current collecting piece located on a side.   The connection part is a band-shaped first connection part that connects one end of the first current collection piece and the other end of the second current collection piece; the other end of the first current collection piece; and the second current collection A strip-shaped second connecting portion that connects one end of the piece, and the current collecting member includes the first current collecting piece, the first connecting portion, the second current collecting piece, and the second connecting portion. A plurality of the fuel cells are arranged in this order in the longitudinal direction of the fuel cells, and the lengths of the connecting portions in the longitudinal direction of the fuel cells are the same, and the fuel cells of each of the connecting portions have the same length. The width in the arrangement direction is wider at the connecting portion located on the other end side in the longitudinal direction of the fuel cell than the connecting portion located on one end side in the longitudinal direction of the fuel cell. The cell stack device according to claim 2. The connection part is a belt-like first connection part that connects one end of the plurality of first current collection pieces and one end of the plurality of second current collection pieces, and the other end of the plurality of first current collection pieces A strip-shaped second connecting portion that connects the other ends of the plurality of second current collecting pieces,
The current collecting member has a plurality of these as a unit in the longitudinal direction of the fuel cell, and the adjacent units are joined via a conductive connecting piece, and the fuel cell of each connecting portion The length in the longitudinal direction of the cells is the same, and the length of each of the connecting portions in the arrangement direction of the fuel cells is the other end of the connecting portion in the longitudinal direction of the fuel cells. The cell stack device according to claim 2, wherein the length is longer than the connection portion located on one end side in the longitudinal direction of the fuel cell.   5. A fuel cell module comprising the cell stack device according to claim 1 stored in a storage container.   6. A fuel cell device comprising: the fuel cell module according to claim 5; and an auxiliary machine for operating the fuel cell module, housed in an outer case.

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