WO2017006790A1

WO2017006790A1 - Fuel cell stack

Info

Publication number: WO2017006790A1
Application number: PCT/JP2016/068954
Authority: WO
Inventors: 誠大森
Original assignee: 日本碍子株式会社
Priority date: 2015-07-03
Filing date: 2016-06-27
Publication date: 2017-01-12

Abstract

This fuel cell stack (100) is provided with: a first power generation element part; a first supporting substrate (5a); a second power generation element part; a second supporting substrate (5b); and a communication member (3). The first supporting substrate (5a) comprises: a first substrate main body part; a first dense layer; and a first gas channel. The first dense layer covers the first substrate main body part. The first gas channel extends from a proximal end part (501a) to a distal end part (502a). The second supporting substrate (5b) comprises: a second substrate main body part; a second dense layer; and a second gas channel. The second dense layer covers the second substrate main body part. The second gas channel extends from a proximal end part (501b) to a distal end part (502b). The communication member (3) extends between the distal end part (502a) of the first supporting substrate (5a) and the distal end part (502b) of the second supporting substrate (5b), and has the first gas channel and the second gas channel be in communication with each other.

Description

Fuel cell stack

The present invention relates to a fuel cell stack.

A fuel cell stack including a plurality of cells and a manifold that distributes gas to each cell is known. Each cell includes a porous support substrate and a power generation element unit supported by each support substrate. By inserting the proximal end portion of each support substrate into the manifold, fuel gas is supplied from the manifold to the gas flow path of each support substrate. Of the fuel gas supplied from the proximal end of the gas flow path of each support substrate, unreacted gas is discharged from the distal end of the gas flow path to the outside.

The fuel cell stack described in Patent Document 1 is configured to collect unreacted gas discharged from the distal end portion to the outside in order to improve the use efficiency of fuel gas. Specifically, the support substrate has a gas flow path for the outward path and a gas flow path for the return path. Of the fuel gas supplied to the outward gas flow path, the unreacted gas is used again for power generation in the return gas flow path. Further, the fuel gas that has flowed through the return gas flow path is not discharged from the distal end portion to the outside, but is recovered from the proximal end portion to the manifold.

Since the support substrate is porous, the fuel gas may flow to the gas path for the return path without flowing to the end for the gas path for the forward path. That is, the fuel gas may flow through the support substrate in the middle of the outward gas flow path to the return gas flow path. In order to prevent such a shortcut, a dense member is inserted between the outward gas passage and the backward gas passage.

Japanese Patent Laying-Open No. 2015-53186

The above-described fuel cell stack has a problem that it is difficult to manufacture the fuel cell stack because a dense member needs to be inserted into the porous support substrate. Therefore, an object of the present invention is to provide a fuel cell stack that can recover gas and can be easily manufactured.

A fuel cell stack according to an aspect of the present invention includes a first power generation element portion, a first support substrate, a second power generation element portion, a second support substrate, and a communication member. The first power generation element unit includes a first fuel electrode, a first electrolyte, and a first air electrode. The first support substrate has a first substrate body, a first dense layer, and a first gas flow path. The first substrate body portion supports the first power generation element portion. The first dense layer covers the first substrate body. The first gas flow path extends from the proximal end to the distal end. The second power generation element unit includes a second fuel electrode, a second electrolyte, and a second air electrode. The second support substrate has a second substrate body, a second dense layer, and a second gas flow path. The second substrate body portion supports the second power generation element portion. The second dense layer covers the second substrate body. The second gas flow path extends from the proximal end to the distal end. The communication member extends between the distal end portion of the first support substrate and the distal end portion of the second support substrate, and communicates the first gas channel and the second gas channel.

According to this configuration, the unreacted gas out of the fuel gas flowing through the first gas flow path of the first support substrate is not discharged from the distal end portion of the first gas flow path to the outside, but communicated. It flows to a 2nd gas flow path through a member. For this reason, the use efficiency of fuel gas can be improved. The first support substrate has a first dense layer that covers the first substrate body, and the second support substrate has a second dense layer that covers the second substrate body. Since the first and second dense layers are denser than the first and second substrate body portions, the fuel gas flowing in the first gas flow path passes through the first and second substrate body portions to form the second gas. It can suppress flowing into the flow path. In addition, the first dense layer may be formed so as to cover the first substrate body, and can be easily formed.

Preferably, the first support substrate and the second support substrate are arranged such that the side surface of the first support substrate and the side surface of the second support substrate face each other.

The first support substrate and the second support substrate may be arranged with a space therebetween. For example, when the fuel cell stack has a large number of cells and is enlarged, the temperature distribution in the stack can be made uniform by flowing air at this interval.

The first support substrate and the second support substrate may be arranged side by side in the width direction. The space between the first support substrate and the second support substrate may be sealed. According to this configuration, the space between the first support substrate and the second support substrate is sealed in the width direction. For this reason, for example, when air flows along the main surfaces of the first support substrate and the second support substrate, it is possible to prevent the air from escaping from between the first support substrate and the second support substrate.

The first support substrate and the second support substrate may be arranged side by side so as to contact each other in the width direction.

The fuel cell stack may further include a filling member. The filling member is disposed so as to fill a space between the first support substrate and the second support substrate that are disposed at a distance from each other.

Preferably, the fuel cell stack includes a plurality of first support substrates and a plurality of second support substrates. Each 1st support substrate is arrange | positioned at intervals so that main surfaces may oppose. Each 2nd support substrate is arrange | positioned at intervals so that main surfaces may oppose. Each first support substrate is arranged side by side with each second support substrate in the width direction. At least a pair of the first support substrate and the second support substrate is sealed.

Preferably, the communication member has a flow path for communicating the first gas flow path and the second gas flow path.

The communicating member may be porous. In this case, it is preferable that the communication member has a third dense layer constituting the outer surface. Moreover, the flow path mentioned above can be comprised by the pore in a communicating member.

The communicating member may have a space extending from the first gas channel to the second gas channel as the channel.

The communicating member may be made of metal.

Preferably, the fuel cell stack includes a plurality of first power generation element units and a plurality of second power generation element units. Each first power generation element portion is arranged at an interval along the longitudinal direction of the first support substrate. Each 2nd electric power generation element part is arrange | positioned at intervals along the longitudinal direction of the 2nd support substrate.

Preferably, the fuel cell stack further includes a manifold that supports the first and second support substrates. With this manifold, fuel gas can be distributed to each gas flow path.

Preferably, the manifold has a first chamber and a second chamber. The first gas flow path is in communication with the first chamber. The second gas flow path communicates with the second chamber. According to this configuration, by supplying the fuel gas to the first chamber, the fuel gas can smoothly flow in the order of the first gas flow path, the communication member, and the second gas flow path.

The manifold may have a manifold body and a partition plate. The manifold main body has a space. The partition plate partitions the space portion into the first chamber and the second chamber. According to this configuration, a manifold having the first and second chambers can be easily manufactured.

The manifold may have a first manifold body and a second manifold body. The first manifold body has a first chamber. The second manifold main body has a second chamber.

Preferably, the manifold may further include a gas supply unit and a gas discharge unit. The gas supply unit is connected to the first chamber. The gas discharge part is connected to the second chamber.

The gas supply unit may be formed on the first side plate of the manifold, and the gas discharge unit may be formed on the second side plate of the manifold. The first side plate and the second side plate of the manifold are disposed on opposite sides.

Both the gas supply part and the gas discharge part may be formed on the first side plate of the manifold.

Preferably, the fuel cell stack may include a plurality of first support substrates and a plurality of second support substrates. The first support substrates are arranged at intervals from each other in the direction in which the first side plate faces. Each of the second support substrates is disposed at a distance from each other in the direction in which the first side plate faces.

Preferably, the first dense layer includes a first electrolyte, and the second dense layer includes a second electrolyte.

The fuel cell stack according to the present invention can recover gas and can easily manufacture the fuel cell stack.

The perspective view of a fuel cell stack. The perspective view of a 1st cell. Sectional drawing of a 1st cell. The perspective view of a 2nd cell. Sectional drawing of a 2nd cell. Sectional drawing of a fuel cell stack. FIG. 10 is a cross-sectional view of a fuel cell stack according to Modification 5. 10 is a perspective view of a fuel cell stack according to Modification 6. FIG. FIG. 10 is a cross-sectional view of a fuel cell stack according to Modification 6. FIG. 10 is a cross-sectional view of a fuel cell stack according to Modification 7. FIG. 10 is a perspective view of a fuel cell stack according to Modification 8. FIG. 10 is a cross-sectional view of a fuel cell stack according to Modification 9.

Hereinafter, embodiments of a fuel cell stack according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a fuel cell stack. In FIG. 1, the description of some first and second cells is omitted.

[Fuel cell stack]
As shown in FIG. 1, the fuel cell stack 100 includes a plurality of first cells 10 a, a plurality of second cells 10 b, a communication member 3, and a manifold 4. In the following, “a” is added to the end of the reference numerals of the constituent members of the first cell 10a, and “b” is attached to the end of the reference numerals of the constituent members of the second cell 10b. Since the first cell 10a and the second cell 10b have substantially the same configuration, only the components of the first cell 10a will be described below, and the components of the second cell 10b will be described in the configuration of the first cell 10a. The reference numerals corresponding to the members are attached and detailed description is omitted.

[Manifold]
The manifold 4 is configured to support the first and

second cells

10a and 10b. The manifold 4 has a first chamber 41 and a second chamber 42. Further, the manifold 4 includes a gas supply unit 101 connected to the first chamber 41 and a gas discharge unit 102 connected to the second chamber 42. Fuel gas is supplied to the first chamber 41 via the gas supply unit 101. Further, the fuel gas in the second chamber 42 is discharged from the manifold 4 through the gas discharge unit 102.

The manifold 4 has a manifold main body 43 and a partition plate 44. The manifold main body 43 has a space inside. The manifold main body 43 has a rectangular parallelepiped shape. The manifold main body 43 includes an upper plate 431, a bottom plate 432, a first side plate 433, a second side plate 434, a third side plate 435, and a fourth side plate 436.

The first to fourth side plates 433 to 436 extend upward from the peripheral edge of the bottom plate 432. The first side plate 433 and the second side plate 434 are arranged on opposite sides. Further, the third side plate 435 and the fourth side plate 436 are disposed on opposite sides. The upper plate 431 is disposed so as to seal the upper surface of the manifold main body 43. The upper plate 431, the bottom plate 432, the first side plate 433, the second side plate 434, the third side plate 435, and the fourth side plate 436 are integrally formed.

A plurality of first and second insertion holes (not shown) are formed in the upper plate 431 of the manifold main body 43. The first cell 10a is inserted into the first insertion hole, and the second cell 10b is inserted into the second insertion hole. The first insertion hole communicates with the first chamber 41, and the second insertion hole communicates with the second chamber 42.

The first insertion holes are arranged at intervals in the longitudinal direction (z-axis direction) of the manifold main body 43. That is, the first insertion holes are formed at intervals in the direction in which the first side plate 433 faces. The second insertion holes are also arranged at intervals in the longitudinal direction (z-axis direction) of the manifold main body 43. That is, the second insertion holes are formed at intervals from each other in the direction in which the first side plate 433 faces. The first insertion hole and the second insertion hole are arranged at intervals in the width direction (y-axis direction) of the manifold main body 43.

The gas supply unit 101 is formed on the first side plate 433. Further, the gas discharge unit 102 is also formed on the first side plate 433. That is, the gas supply unit 101 and the gas discharge unit 102 are formed on the same first side plate 433.

The partition plate 44 partitions the space of the manifold main body 43 into a first chamber 41 and a second chamber 42. Specifically, the partition plate 44 extends in the longitudinal direction of the manifold main body 43 at a substantially central portion of the manifold main body 43. Although it is preferable that the partition plate 44 completely partitions the space of the manifold main body 43, a gap may be formed between the partition plate 44 and the manifold main body 43.

[First cell]
The first cell 10 a is disposed above the first chamber 41 of the manifold 4. The first cell 10 a is inserted into the first insertion hole of the manifold 4. The second cell 10 b is disposed above the second chamber 42 of the manifold 4. The second cell 10 b is inserted into the second insertion hole of the manifold 4.

The first cells 10a are arranged so that the main surfaces face each other. In addition, the first cells 10 a are arranged at intervals along the longitudinal direction of the manifold 4. The second cells 10b are arranged so that the main surfaces face each other. The second cells 10b are arranged at intervals along the longitudinal direction of the manifold 4. The row of the first cells 10a and the row of the second cells 10b are arranged substantially in parallel. The 1st cell 10a and the 2nd cell 10b are arrange | positioned so that a side surface may oppose.

As shown in FIG. 2, the first cell 10a includes a first support substrate 5a and a plurality of first power generation element portions 2a. Each first power generation element portion 2a may be supported only on one main surface 503a of the first support substrate 5a, or may be supported on both main surfaces 503a of the first support substrate 5a. In the present embodiment, each first power generation element portion 2a is supported on both main surfaces 503a of the first support substrate 5a. The first power generation element portions 2a are electrically connected to each other by a first electrical connection portion 9a (see FIG. 3).

[First support substrate]
The first support substrate 5a includes a first substrate body 51a, a first dense layer 52a, and a plurality of first gas flow paths 53a. The first support substrate 5a has a proximal end 501a and a distal end 502a. The proximal end portion 501a and the distal end portion 502a are both end portions in the longitudinal direction (x-axis direction) of the first support substrate 5a. The proximal end portion 501 a of the first support substrate 5 a is inserted into the first insertion hole of the manifold 4.

The first support substrate 5a has two main surfaces 503a and two side surfaces 504a. Each main surface 503a supports each first power generation element portion 2a. Each main surface 503a faces the thickness direction (z-axis direction) of the first support substrate 5a. Each side surface 504a faces the width direction (y-axis direction) of the first support substrate 5a. Each side surface 504a may be curved. As shown in FIG. 1, each 1st support substrate 5a is arrange | positioned at intervals so that main surface 503a may oppose. The first support substrates 5a are arranged at intervals from each other in the direction (z-axis direction) in which the first side plate 433 faces.

As shown in FIG. 2, the first substrate body 51a supports the first power generation element 2a. The first substrate body 51a is made of a porous material that does not have electronic conductivity. The first substrate body 51a is made of CSZ (calcia stabilized zirconia), for example. Alternatively, the first substrate body 51a may be composed of NiO (nickel oxide) and YSZ (8YSZ) (yttria-stabilized zirconia), or from NiO (nickel oxide) and Y ₂ O ₃ (yttria). may be constituted, MgO may be configured from (magnesium oxide) and MgAl ₂ O ₄ and (magnesia alumina spinel). The porosity of the first substrate body 51a is, for example, about 20 to 60%. This porosity is measured, for example, by Archimedes method or microstructure observation.

The first dense layer 52a covers the first substrate body 51a. The first dense layer 52a only needs to be able to prevent the fuel gas flowing through the first gas flow path 53a from flowing through the first substrate body 51a to the second gas flow path 53b. It is not necessary to cover the entire surface of 51a. In the present embodiment, the first dense layer 52a covers each main surface and each side surface of the first substrate body 51a. That is, the first dense layer 52a constitutes each main surface 503a of the first support substrate 5a and constitutes each side surface 504a of the first support substrate 5a. In the present embodiment, the first dense layer 52a includes a first electrolyte 7a described later and a first interconnector 91a. The first dense layer 52a is denser than the first substrate body 51a. For example, the porosity of the first dense layer 52a is about 0 to 7%.

The first gas channel 53a extends from the proximal end 501a to the distal end 502a of the first support substrate 5a. The first gas channel 53a extends along the longitudinal direction (x-axis direction) of the first support substrate 5a. The first gas channel 53a extends through the first substrate body 51a. A proximal end portion 531 a of the first gas flow path 53 a communicates with the first chamber 41. Further, the distal end portion 532a of the first gas flow path 53a communicates with the flow path 30 of the communication member 3 described later.

[First power generation element section]
As shown in FIG. 3, the 1st electric power generation element part 2a has the 1st fuel electrode 6a, the 1st electrolyte 7a, and the 1st air electrode 8a. The first power generation element portion 2a further includes a first reaction preventing film 11a. The first fuel electrode 6a is a fired body made of a porous material having electron conductivity. The first fuel electrode 6a includes a first fuel electrode current collector 61a and a fuel electrode active part 62a.

The first fuel electrode current collector 61a is disposed in the recess 513a. The recesses 513a are formed on both surfaces of the first substrate body 51a. Specifically, the first fuel electrode current collector 61a is filled in the recess 513a and has the same outer shape as the recess 513a. Each first fuel electrode current collector 61a has a recess 611a and a recess 612a. The anode active part 62a is disposed in the recess 611a. Specifically, the fuel electrode active part 62a is filled in the recess 611a.

The first fuel electrode current collector 61a can be composed of, for example, NiO (nickel oxide) and YSZ (8YSZ) (yttria stabilized zirconia). Alternatively, the first fuel electrode current collector 61a may be composed of NiO (nickel oxide) and Y ₂ O ₃ (yttria), or composed of NiO (nickel oxide) and CSZ (calcia stabilized zirconia). May be. The thickness of the first fuel electrode current collector 61a and the depth of the recess 513a are about 50 to 500 μm.

The fuel electrode active part 62a may be composed of, for example, NiO (nickel oxide) and YSZ (8YSZ) (yttria stabilized zirconia). Alternatively, the fuel electrode active part 62a may be composed of NiO (nickel oxide) and GDC (gadolinium-doped ceria). The thickness of the anode active portion 62a is 5 to 30 μm.

The first electrolyte 7a is disposed so as to cover the first fuel electrode 6a. Specifically, the first electrolyte 7a extends in the longitudinal direction from one first interconnector 91a to the other first interconnector 91a. That is, the first electrolyte 7a and the first interconnector 91a are alternately arranged in the longitudinal direction. The first electrolyte 7a covers each main surface and each side surface of the first substrate body 51a.

The first electrolyte 7a is denser than the first substrate body 51a. For example, the porosity of the first electrolyte 7a is about 0 to 7%. The first electrolyte 7a is a fired body made of a dense material having ion conductivity and not electron conductivity. The first electrolyte 7a can be composed of, for example, YSZ (8YSZ) (yttria stabilized zirconia). Or you may comprise from LSGM (lantern gallate). The thickness of the first electrolyte 7a is, for example, about 3 to 50 μm.

The first reaction preventing film 11a is a fired body made of a dense material and has substantially the same shape as the fuel electrode active part 62a in plan view. The first reaction preventing film 11a is disposed at a position corresponding to the fuel electrode active part 62a via the first electrolyte 7a. The first reaction preventing film 11a has a reaction layer having a large electric resistance at the interface between the first electrolyte 7a and the first air electrode 8a due to a reaction between YSZ in the first electrolyte 7a and Sr in the first air electrode 8a. It is provided to suppress the occurrence of the phenomenon that is formed. The first reaction preventing film 11a can be made of, for example, GDC = (Ce, Gd) O ₂ (gadolinium-doped ceria). The thickness of the first reaction preventing film 11a is, for example, about 3 to 50 μm.

The first air electrode 8a is disposed on the first reaction preventing film 11a. The first air electrode 8a is a fired body made of a porous material having electron conductivity. The first air electrode 8a can be made of, for example, LSCF = (La, Sr) (Co, Fe) O ₃ (lanthanum strontium cobalt ferrite). Alternatively, from LSF = (La, Sr) FeO ₃ (lanthanum strontium ferrite), LNF = La (Ni, Fe) O ₃ (lanthanum nickel ferrite), LSC = (La, Sr) CoO ₃ (lanthanum strontium cobaltite), etc. It may be configured. The first air electrode 8a may be composed of two layers of a first layer (inner layer) made of LSCF and a second layer (outer layer) made of LSC. The thickness of the first air electrode 8a is, for example, 10 to 100 μm.

The first electrical connection portion 9a is configured to electrically connect the adjacent first power generation element portions 2a. The first electrical connection portion 9a includes a first interconnector 91a and a first air electrode current collector film 92a. The first interconnector 91a is disposed in the recess 612a. Specifically, the first interconnector 91a is embedded (filled) in the recess 612a. The first interconnector 91a is a fired body made of a dense material having electronic conductivity. The first interconnector 91a is denser than the first substrate body 51a. For example, the porosity of the first interconnector 91a is about 0 to 7%. The first interconnector 91a can be composed of, for example, LaCrO ₃ (lanthanum chromite). Alternatively, it may be composed of (Sr, La) TiO ₃ (strontium titanate). The thickness of the first interconnector 91a is, for example, 10 to 100 μm.

The first air electrode current collector film 92a is disposed so as to extend between the first interconnector 91a and the first air electrode 8a of the adjacent first power generation element portion 2a. For example, the first air electrode 8a of the first power generation element portion 2a disposed on the left side in FIG. 3 and the first interconnector 91a of the first power generation element portion 2a disposed on the right side in FIG. 3 are electrically connected. Thus, the first air electrode current collector film 92a is disposed. The first air electrode current collector film 92a is a fired body made of a porous material having electron conductivity.

The first air electrode current collector film 92a can be made of, for example, LSCF = (La, Sr) (Co, Fe) O ₃ (lanthanum strontium cobalt ferrite). Alternatively, LSC = (La, Sr) CoO ₃ (lanthanum strontium cobaltite) may be used. Alternatively, it may be made of Ag (silver) or Ag—Pd (silver palladium alloy). The thickness of the first air electrode current collector film 92a is, for example, about 50 to 500 μm.

[Second cell]
As shown in FIG.4 and FIG.5, the 2nd cell 10b has the 2nd support substrate 5b and the 2nd electric power generation element part 2b. As shown in FIG. 1, the second support substrates 5b are arranged so that the main surfaces 503b face each other. The respective second support substrates 5b are arranged at intervals from each other in the direction (z-axis direction) in which the first side plate 433 faces.

As shown in FIGS. 4 and 5, the second support substrate 5b has a second substrate body 51b, a second dense layer 52b, and a second gas channel 53b. The second support substrate 5b has a proximal end portion 501b and a distal end portion 502b. The proximal end portion 501 b of the second support substrate 5 b is inserted into the second insertion hole of the manifold 4. The second substrate body 51b supports a plurality of second power generation element portions 2b. The second dense layer 52b covers the second substrate body 51b. The second gas channel 53b extends from the proximal end 501b to the distal end 502b of the second support substrate 5b.

The second power generation element portion 2b has a second fuel electrode 6b, a second electrolyte 7b, and a second air electrode 8b. As described above, each second cell 10b has substantially the same configuration as the first cell 10a, and thus detailed description thereof is omitted. The second power generation element portion 2b may have a larger area in contact with the fuel gas than the first power generation element portion 2a. That is, the area of the second fuel electrode 6b may be larger than the area of the first fuel electrode 6a. The area of the second air electrode 8b may be larger than the area of the first air electrode 8a. Of course, the area of the second fuel electrode 6b may be the same as the area of the first fuel electrode 6a or may be smaller than the area of the first fuel electrode 6a. The area of the second air electrode 8b may be the same as the area of the first air electrode 8a or may be smaller than the area of the first air electrode 8a.

As shown in FIG. 1, the first support substrates 5 a are arranged at intervals so that the main surfaces 503 a face each other. In addition, the second support substrates 5b are arranged at intervals so that the main surfaces 503b face each other. The first support substrate 5a and the second support substrate 5b are arranged side by side in the width direction (y-axis direction). The first and

second support substrates

5a and 5b are arranged so that the side surface 504a of the first support substrate 5a faces the side surface 504b of the second support substrate 5b. A gap is formed between the first support substrate 5a and the second support substrate 5b. For example, the gap can be about 0.5 to 10 mm.

[Communication member]
As shown in FIG. 6, the communication member 3 extends over the distal end portion 502a of the first support substrate 5a and the distal end portion 502b of the second support substrate 5b. And the communication member 3 has the flow path 30 which connects the 1st gas flow path 53a and the 2nd gas flow path 53b. Specifically, the channel 30 communicates the distal end 532a of each first gas channel 53a and the distal end 532b of each second gas channel 53b. The flow path 30 is comprised by the space extended from each 1st gas flow path to each 2nd gas flow path. The communication member 3 is preferably bonded to the first support substrate 5a and the second support substrate 5b.

The communicating member 3 is porous. Further, the communication member 3 has a third dense layer 31 that constitutes the outer surface thereof. The third dense layer 31 is formed more densely than the main body of the communication member 3. For example, the porosity of the third dense layer 31 is about 0 to 7%. The third dense layer 31 can be formed of the same material as the communication member, an electrolyte material, crystallized glass, or the like.

[Power generation method]
In the fuel cell stack 100 configured as described above, fuel gas such as hydrogen gas is supplied to the first chamber 41 of the manifold 4, and the first and

second cells

10a and 10b are made into gas containing oxygen such as air. Expose. Specifically, air is supplied between the adjacent first cells 10a and between the adjacent second cells 10b. Then, the chemical reaction shown in the following formula (1) occurs in the first air electrode 8a and the second air electrode 8b, and the chemical reaction shown in the following formula (2) occurs in the first fuel electrode 6a and the second fuel electrode 6b. Current flows.
(1/2) · O ₂ + 2e ⁻ → O ₂ ⁻ (1)
H ₂ + O ₂ ⁻ → H ₂ O + 2e ⁻ (2)

More specifically, the fuel gas supplied to the first chamber 41 flows in the first gas flow path 53a of each first cell 10a, and the above (2) in the first fuel electrode 6a of each first power generation element portion 2a. The chemical reaction shown in the formula occurs. The unreacted fuel gas in each first fuel electrode 6a exits the first gas channel 53a and is supplied to the second gas channel 53b through the channel 30 of the communication member 3. The fuel gas supplied to the second gas passage 53b undergoes a chemical reaction represented by the above formula (2) at the second fuel electrode 6b of the second cell 10b. The unreacted fuel gas in the second fuel electrode 6 b is collected in the second chamber 42 of the manifold 4.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

Modification 1
For example, in the above embodiment, the fuel gas is supplied to the first chamber 41 and the fuel gas is discharged from the second chamber 42, but the flow of the fuel gas is not particularly limited to this. For example, fuel gas may be supplied to the second chamber 42 and discharged from the first chamber 41. That is, the fuel gas may flow in the order of the second gas flow path, the communication member 3, and the first gas flow path.

Modification 2
In the embodiment described above, the first support substrate 5a includes the plurality of first gas flow paths 53a, but the number of the first gas flow paths 53a may be one. In this case, the first gas flow path 53a is preferably flat.

Modification 3
In the above embodiment, the first cells 10a and the second cells 10b are arranged in the longitudinal direction (z-axis direction) of the manifold 4, but may be arranged in the width direction (y-axis direction) of the manifold 4.

Modification 4
In the said embodiment, although the communication member 3 is porous, the communication member 3 may be comprised with the metal. Specifically, the communication member 3 can be made of an Fe—Cr alloy, a Ni-based alloy, or an MgO-based ceramic material (may be the same as the support substrate material).

Modification 5
In the said embodiment, although the flow path 30 of the communication member 3 was comprised by space, the structure of the flow path 30 of the communication member 3 is not limited to this. For example, as shown in FIG. 7, the flow path 30 of the communication member 3 can be configured by a plurality of pores formed in the communication member 3.

Modification 6
In the above embodiment, the side surface 504a of the first support substrate 5a and the side surface 504b of the second support substrate 5b are spaced apart from each other, but are not limited thereto. For example, as shown in FIGS. 8 and 9, the side surface 504a of the first support substrate 5a and the side surface 504b of the second support substrate 5b may be sealed. For example, the first support substrate 5a and the second support substrate 5b may be disposed so as to contact each other in the width direction (y-axis direction). That is, the side surface 504a of the first support substrate 5a and the side surface 504b of the second support substrate 5b are in contact with each other.

In this case, the first insertion hole and the second insertion hole may be connected to each other. That is, one insertion hole may be constituted by the first insertion hole and the second insertion hole. The first cell 10 a is inserted into the insertion hole, and the lower end surface of the first cell 10 a is exposed to the first chamber 41. The second cell 10 b is inserted into the insertion hole, and the lower end surface of the second cell 10 b is exposed to the second chamber 42. Each insertion hole may extend over the first chamber 41 and the second chamber 42, or may be formed in each of the first chamber 41 and the second chamber 42.

Modification 7
In Modification 6, the side surface 504a of the first support substrate 5a and the side surface 504b of the second support substrate 5b are in contact with each other. For example, as shown in FIG. 10, the first support substrate 5a and the second support substrate 5b May be arranged at intervals in the width direction (y-axis direction). And the filling member 54 may be arrange | positioned between the 1st support substrate 5a and the 2nd support substrate 5b. The filling member 54 may seal between the first support substrate 5a and the second support substrate 5b.

In the modified examples 6 and 7, the space between each of the first support substrates 5a and each of the second support substrates 5b is sealed, but between some of the first support substrates 5a and the second support substrates 5b. May not be blocked.

Modification 8
In the above embodiment, the gas supply unit 101 and the gas discharge unit 102 of the manifold 4 are formed on the same first side plate 433, but are not particularly limited thereto. For example, as shown in FIG. 11, the gas supply unit 101 may be formed on the first side plate 433 and the gas discharge unit may be formed on the second side plate 434.

Modification 9
In the above embodiment, the manifold 4 is configured by one manifold body 43, but the configuration of the manifold 4 is not limited to this. For example, as shown in FIG. 12, the manifold 4 may have a first manifold main body 43a and a second manifold main body 43b. The first manifold body 43 a has a first chamber 41, and the second manifold body 43 b has a second chamber 42.

2a: 1st electric power generation element part 6a: 1st fuel electrode 7a: 1st electrolyte 8a: 1st air electrode 2b: 2nd electric power generation element part 6b: 2nd fuel electrode 7b: 2nd electrolyte 8b: 2nd air electrode 3: Communication member 30: channel 31: third dense layer 5a: first support substrate 51a: first substrate body 52a: first dense layer 53a: first gas channel 531a: proximal end 532a: distal end 501a: Proximal end portion 502a: Distal end portion 504a: Side surface 5b: Second support substrate 51b: Second substrate body portion 52b: Second dense layer 53b: Second gas flow path 532b: Distal end portion 501b: Near Upper end portion 502b: Distal end portion 504b: Side surface 100: Fuel cell stack

Claims

A first power generation element portion having a first fuel electrode, a first electrolyte, and a first air electrode;
A first substrate body supporting the first power generation element; a first dense layer covering the first substrate body; and a first gas flow path extending from the proximal end to the distal end. A support substrate;
A second power generation element portion having a second fuel electrode, a second electrolyte, and a second air electrode;
A second substrate main body supporting the second power generation element, a second dense layer covering the second substrate main body, and a second gas flow path extending from the proximal end to the distal end. 2 support substrates;
A communication member extending across a distal end portion of the first support substrate and a distal end portion of the second support substrate and communicating the first gas flow path and the second gas flow path;
A fuel cell stack comprising:
The first support substrate and the second support substrate are disposed such that a side surface of the first support substrate and a side surface of the second support substrate face each other.
The fuel cell stack according to claim 1.
The first support substrate and the second support substrate are disposed with a space therebetween.
The fuel cell stack according to claim 1 or 2.
The first support substrate and the second support substrate are arranged side by side in the width direction,
The space between the first support substrate and the second support substrate is sealed,
The fuel cell stack according to claim 1 or 2.
The first support substrate and the second support substrate are arranged side by side so as to contact each other in the width direction.
The fuel cell stack according to claim 4.
A filling member disposed to fill a space between the first support substrate and the second support substrate that are spaced apart from each other;
The fuel cell stack according to claim 4 or 5.
The fuel cell stack includes a plurality of the first support substrates and a plurality of the second support substrates,
Each of the first support substrates is arranged with an interval so that the main surfaces face each other,
Each of the second support substrates is arranged with an interval so that the main surfaces face each other,
The first support substrates are arranged side by side in the width direction with the second support substrates,
Between at least a pair of the first support substrate and the second support substrate is sealed,
The fuel cell stack according to any one of claims 4 to 6.
The communication member has a flow path for communicating the first gas flow path and the second gas flow path.
The fuel cell stack according to any one of claims 1 to 7.
The communication member is porous.
The fuel cell stack according to any one of claims 1 to 8.
The communication member has a third dense layer constituting the outer surface.
The fuel cell stack according to claim 9.
The flow path is configured by pores in the communication member.
The fuel cell stack according to claim 9 or 10.
The communication member has a space extending from the first gas flow path to the second gas flow path as a flow path for communicating the first gas flow path and the second gas flow path.
The fuel cell stack according to claim 1.
The communication member is made of metal.
The fuel cell stack according to any one of claims 1 to 12.
The fuel cell stack includes a plurality of the first power generation element units and a plurality of the second power generation element units,
Each of the first power generation element portions is disposed at intervals along the longitudinal direction of the first support substrate,
Each of the second power generation element portions is disposed at an interval along the longitudinal direction of the second support substrate.
The fuel cell stack according to any one of claims 1 to 13.
A manifold for supporting the first and second support substrates;
The fuel cell stack according to any one of claims 1 to 14.
The manifold has a first chamber and a second chamber,
The first gas flow path communicates with the first chamber;
The second gas flow path communicates with the second chamber;
The fuel cell stack according to claim 15.
The manifold is
A manifold body having a space,
A partition plate that partitions the space portion into the first chamber and the second chamber;
Having
The fuel cell stack according to claim 16.
The manifold includes a first manifold main body having the first chamber and a second manifold main body having the second chamber.
The fuel cell stack according to claim 16.
The manifold further includes a gas supply unit connected to the first chamber and a gas discharge unit connected to the second chamber.
The fuel cell stack according to any one of claims 16 to 18.
The gas supply unit is formed on a first side plate of the manifold,
The gas discharge part is formed on a second side plate disposed on the opposite side of the first side plate,
The fuel cell stack according to claim 19.
The gas supply unit and the gas discharge unit are formed on a first side plate of the manifold.
The fuel cell stack according to claim 19.
The fuel cell stack includes a plurality of the first support substrates and a plurality of the second support substrates,
Each of the first support substrates is disposed at a distance from each other in the direction in which the first side plate faces.
Each of the second support substrates is disposed at a distance from each other in the direction in which the first side plate faces.
The fuel cell stack according to claim 20 or 21.
The first dense layer includes the first electrolyte,
The second dense layer includes the second electrolyte.
The fuel cell stack according to any one of claims 1 to 22.