JP2017117659A - Manifold, and fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent collapse of a fuel cell stack.SOLUTION: A manifold 20 includes a manifold body 3, a lid member 4, and a pair of legs 5. The bottom wall 31 of the manifold body 3 is placed on a placement surface 300. A pair of first sidewalls 32 are extending upward, respectively, from a pair of edges extending in the longitudinal direction of the bottom wall 31. The lid member 4 has an insertion hole into which the lower end of a fuel cell 10 is inserted. The lid member 4 closes the upper surface of the manifold body 3. The pair of legs 5 are placed on the outside of respective first sidewalls 32, and abut against the placement surface 300.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a manifold and a fuel cell stack.

  The fuel cell stack includes a manifold and a plurality of fuel cells (see Patent Document 1). Each fuel cell is supported by the manifold so as to extend upward from the manifold.

Japanese Patent Laying-Open No. 2015-164094

  In the fuel cell stack as described above, since the plurality of fuel cells extend upward, the center of gravity becomes high and becomes unstable and may fall down.

  An object of the present invention is to prevent the fuel cell stack from collapsing.

  The manifold according to the first aspect of the present invention is a manifold for distributing gas to fuel cells. The manifold includes a manifold body, a lid member, and a pair of legs. The manifold body has a bottom wall and a pair of first side walls. The bottom wall is placed on the placement surface. The pair of first side walls extends upward from each of the pair of edges extending in the longitudinal direction of the bottom wall. The lid member has an insertion hole into which the lower end portion of the fuel battery cell is inserted. The lid member closes the upper surface of the manifold body. The pair of leg portions are disposed outside the first side walls and are configured to contact the placement surface.

  According to this structure, a pair of leg part is arrange | positioned on the outer side of the 1st side wall of a manifold main body, and contact | abuts on a mounting surface. For this reason, even when the manifold supports the fuel battery cells and the center of gravity becomes high, the fuel cell stack can be prevented from falling.

  Each leg portion extends downward from the lid member, for example. In this case, each leg portion and the lid member are preferably constituted by one member.

  Further, each leg may extend downward from the first side wall. In this case, it is preferable that each wall part and each first side wall are constituted by one member.

  Moreover, it is preferable that each 1st side wall has a side wall main-body part extended upwards from a bottom wall, and a flange part extended outward from the upper end part of a side wall main-body part. The leg portion preferably extends downward from the flange portion.

  A fuel cell stack according to a second aspect of the present invention includes any of the manifolds described above and a fuel cell. Each fuel cell has a lower end inserted into the insertion hole and extends upward from the lid member.

  According to the present invention, the fuel cell stack can be prevented from falling down.

The perspective view of a fuel cell stack. The perspective view of a fuel cell. The expanded sectional view of a fuel cell. Sectional drawing of a fuel cell stack. The top view of a cover member. FIG. 6 is a cross-sectional view of a fuel cell stack according to Modification 1. FIG. 6 is a cross-sectional view of another fuel cell stack according to Modification 1. FIG. 10 is a perspective view of a fuel cell stack according to Modification 2. FIG. 6 is a cross-sectional view of a fuel cell stack according to Modification 2. FIG. 10 is a cross-sectional view of a fuel cell stack according to Modification 3. FIG. 10 is a cross-sectional view of another fuel cell stack according to Modification 3. FIG. 10 is a cross-sectional view of another fuel cell stack according to Modification 4.

  Hereinafter, an embodiment of a fuel cell stack according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the fuel cell stack 100 includes a plurality of fuel cells 10 and a manifold 20. Each fuel cell 10 is supported by a manifold 20. The manifold 20 distributes the gas to each fuel cell 10.

[Fuel battery cell]
Each fuel cell 10 extends upward from the manifold 20. The longitudinal direction (x-axis direction) of the fuel cell 10 extends in the vertical direction. Further, the fuel cells 10 are arranged at intervals from each other along the longitudinal direction (z-axis direction) of the manifold 20. Each fuel battery cell 10 is electrically connected to each other via a current collecting member (not shown). The current collecting member is formed from a conductive material. For example, the current collecting member is formed of a sintered body of oxide ceramics or a metal.

  As shown in FIG. 2, the fuel battery cell 10 includes a plurality of power generation element portions 11 and a support substrate 12. Each power generating element portion 11 is supported on both surfaces of the support substrate 12. Each power generation element unit 11 may be supported only on one side of the support substrate 12. The respective power generation element portions 11 are arranged at intervals in the longitudinal direction of the fuel battery cell 10. That is, the fuel cell 10 according to the present embodiment is a so-called horizontal stripe type fuel cell. The power generating element portions 11 are electrically connected to each other by an electrical connection portion 17 (see FIG. 3).

  The support substrate 12 has a plurality of gas flow paths 121 extending in the longitudinal direction of the fuel cell 10 inside. The longitudinal direction (x-axis direction) of the support substrate 12 is the same direction as the longitudinal direction of the fuel cell 10. Each gas channel 121 extends substantially parallel to each other. Each gas flow path 121 is open at both ends in the longitudinal direction of the fuel cell 10. Each gas flow path 121 is not formed at both ends 122 in the width direction (y-axis direction) of the fuel cell 10. Both end portions 122 in the width direction of the fuel cell 10 in which the gas flow path 121 is not formed are placed on a first flange portion 322 of the first side wall 32 described later.

  As shown in FIG. 3, the support substrate 12 has a plurality of first recesses 123. Each first recess 123 is formed on both surfaces of the support substrate 12. The first recesses 123 are arranged at intervals in the longitudinal direction of the support substrate 12.

The support substrate 12 is made of a porous material that does not have electronic conductivity. The support substrate 12 can be made of, for example, CSZ (calcia stabilized zirconia). Alternatively, the support substrate 12 may be composed of NiO (nickel oxide) and YSZ (8YSZ) (yttria stabilized zirconia), or composed of NiO (nickel oxide) and Y ₂ O ₃ (yttria). Alternatively, MgO (magnesium oxide) and MgAl ₂ O ₄ (magnesia alumina spinel) may be used. The porosity of the support substrate 12 is, for example, about 20 to 60%.

  Each power generation element unit 11 includes a fuel electrode 13, an electrolyte 14, and an air electrode 15. Each power generation element unit 11 further includes a reaction preventing film 16. The fuel electrode 13 is a fired body made of a porous material having electron conductivity. The fuel electrode 13 includes a fuel electrode current collector 131 and a fuel electrode active part 132.

  The fuel electrode current collector 131 is disposed in the first recess 123. Specifically, the fuel electrode current collector 131 is filled in the first recess 123 and has the same outer shape as the first recess 123. Each fuel electrode current collector 131 has a second recess 131a and a third recess 131b. The anode active part 132 is disposed in the second recess 131a. Specifically, the fuel electrode active part 132 is filled in the second recess 131a.

The fuel electrode current collector 131 can be composed of, for example, NiO (nickel oxide) and YSZ (8YSZ) (yttria stabilized zirconia). Alternatively, the fuel electrode current collector 131 may be composed of NiO (nickel oxide) and Y ₂ O ₃ (yttria), or composed of NiO (nickel oxide) and CSZ (calcia stabilized zirconia). Also good. The thickness of the fuel electrode current collector 131 and the depth of the first recess 123 are about 50 to 500 μm.

  The fuel electrode active part 132 can be composed of, for example, NiO (nickel oxide) and YSZ (8YSZ) (yttria stabilized zirconia). Alternatively, the fuel electrode active part 132 may be composed of NiO (nickel oxide) and GDC (gadolinium-doped ceria). The thickness of the fuel electrode active part 132 is 5 to 30 μm.

  The electrolyte 14 is disposed so as to cover the fuel electrode 13. Specifically, the electrolyte 14 extends in the longitudinal direction of the fuel cell 10 from one interconnector 171 to another interconnector 171. That is, the electrolyte 14 and the interconnector 171 are alternately arranged in the longitudinal direction of the fuel battery cell 10.

  The electrolyte 14 is a fired body made of a dense material that has ionic conductivity and no electronic conductivity. The electrolyte 14 can be composed of, for example, YSZ (8YSZ) (yttria stabilized zirconia). Or the electrolyte 14 may be comprised from LSGM (lanthanum gallate). The thickness of the electrolyte 14 is, for example, about 3 to 50 μm.

The reaction preventing film 16 is a fired body made of a dense material, has substantially the same shape as the fuel electrode active part 132 in a plan view (viewed in the z-axis direction), and is disposed at substantially the same position as the fuel electrode active part 132. Has been. The reaction preventing film 16 suppresses occurrence of a phenomenon in which a reaction layer having a large electric resistance is formed at the interface between the electrolyte 14 and the air electrode 15 due to a reaction between YSZ in the electrolyte 14 and Sr in the air electrode 15. Is provided. The reaction preventing film 16 can be made of, for example, GDC = (Ce, Gd) O ₂ (gadolinium-doped ceria). The thickness of the reaction preventing film 16 is, for example, about 3 to 50 μm.

The air electrode 15 is disposed on the reaction preventing film 16. The air electrode 15 is a fired body made of a porous material having electron conductivity. The air electrode 15 can be made of, for example, LSCF = (La, Sr) (Co, Fe) O ₃ (lanthanum strontium cobalt ferrite). Alternatively, the air electrode 15 has LSF = (La, Sr) FeO ₃ (lanthanum strontium ferrite), LNF = La (Ni, Fe) O ₃ (lanthanum nickel ferrite), or LSC = (La, Sr) CoO ₃ ( Lanthanum strontium cobaltite) or the like. The air electrode 15 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 air electrode 15 is, for example, 10 to 100 μm.

The electrical connection portion 17 is configured to electrically connect adjacent power generation element portions 11. The electrical connection portion 17 includes an interconnector 171 and an air electrode current collector film 172. The interconnector 171 is disposed in the third recess 131b. Specifically, the interconnector 171 is embedded (filled) in the third recess 131b. The interconnector 171 is a fired body made of a dense material having electronic conductivity. The interconnector 171 can be composed of, for example, LaCrO ₃ (lanthanum chromite). Alternatively, the interconnector 171 may be made of (Sr, La) TiO ₃ (strontium titanate). The thickness of the interconnector 171 is, for example, 10 to 100 μm.

  The air electrode current collector film 172 is disposed so as to extend between the interconnector 171 and the air electrode 15 of the adjacent power generation element portions 11. For example, the air electrode current collector is connected so as to electrically connect the air electrode 15 of the power generating element unit 11 disposed on the left side of FIG. 3 and the interconnector 171 of the power generating element unit 11 disposed on the right side of FIG. A membrane 172 is disposed. The air electrode current collector film 172 is a fired body made of a porous material having electron conductivity.

The air electrode current collector film 172 can be made of, for example, LSCF = (La, Sr) (Co, Fe) O ₃ (lanthanum strontium cobalt ferrite). Alternatively, the air electrode current collector film 172 may be made of LSC = (La, Sr) CoO ₃ (lanthanum strontium cobaltite). Or the air electrode current collection film | membrane 172 may be comprised from Ag (silver) and Ag-Pd (silver palladium alloy). The thickness of the air electrode current collector film 172 is, for example, about 50 to 500 μm.

[Manifold]
As shown in FIGS. 1 and 4, the manifold 20 is configured to distribute gas to each fuel cell 10. The manifold 20 is hollow and has an internal space. A gas such as fuel gas is supplied to the internal space of the manifold 20 through the introduction pipe 201. The manifold 20 supports each fuel cell 10. The manifold 20 includes a manifold body 3, a lid member 4, and legs 5.

  The manifold body 3 has a rectangular parallelepiped shape and has an internal space whose upper surface is open. Specifically, the manifold body 3 has a bottom wall 31, a pair of first side walls 32, and a pair of second side walls 33. The manifold body 3 is composed of one member. That is, the bottom wall 31, the pair of first side walls 32, and the pair of second side walls 33 are configured by one member. The manifold body 3 is formed of a metal having heat resistance, for example. More specifically, the manifold body 3 is formed of at least one selected from the group consisting of ferritic stainless steel, austenitic stainless steel, and Ni-based alloy.

  The bottom wall 31 has a rectangular shape in plan view (viewed in the x-axis direction). The bottom wall 31 has a longitudinal direction (z-axis direction) and a short direction (y-axis direction) in plan view. When the manifold 20 is placed on the placement surface 300, the bottom wall 31 is placed on the placement surface 300. That is, the bottom wall 31 contacts the placement surface 300.

  The pair of first side walls 32 extends upward from each of a pair of opposed edges of the bottom wall 31. Specifically, each first side wall 32 extends upward from a pair of edges extending in the longitudinal direction (z-axis direction) among the edges of the bottom wall 31. The first side wall 32 extends in the longitudinal direction (z-axis direction) of the manifold 20. That is, it extends in the direction in which the plurality of fuel cells 10 are arranged. The pair of first side walls 32 face each other.

  The first side wall 32 has a first side wall main body 321 and a first flange 322. The first side wall body 321 is a portion extending upward from the bottom wall 31. The first flange portion 322 is a portion extending outward from the upper end portion of the first side wall main body portion 321. In addition, the 1st side wall main-body part 321 and the 1st flange part 322 are extended integrally.

  The pair of second side walls 33 extends upward from the remaining opposing edges of the bottom wall 31. Each second side wall 33 extends in the width direction (y-axis direction) of the manifold 20. That is, each second side wall 33 extends in the width direction of the fuel cell 10. The second side walls 33 face each other. Similar to the first side wall 32, the second side wall 33 has a second side wall main body portion and a second flange portion. The second side wall main body portion is continuous with the first side wall main body portion 321, and the second flange portion is continuous with the first flange portion 322.

  The lid member 4 is configured to close the upper surface of the manifold body 3. The outer peripheral edge portion of the lid member 4 is disposed on the first flange portion 322 and the second flange portion, and is joined to the first flange portion 322 and the second flange portion. The lid member 4 is joined to the first flange portion 322 and the second flange portion by welding, for example.

  As shown in FIG. 5, the lid member 4 has a plurality of insertion holes 41. The lower end portion of each fuel cell 10 is inserted into each insertion hole 41. Each insertion hole 41 extends in the width direction (y-axis direction) of the manifold 20. Further, the insertion holes 41 are arranged at intervals in the longitudinal direction of the manifold 20.

  The length of the lid member 4 in the short direction (y-axis direction) is longer than the length of the manifold body 3 in the short direction (y-axis direction). For this reason, both end portions in the short direction of the lid member 4 extend beyond the first flange portion 322.

  As shown in FIGS. 1 and 4, the pair of leg portions 5 are configured to prevent the fuel cell stack 100 from falling over. Each leg 5 is arranged outside each first side wall 32. Each leg part 5 is comprised so that the mounting surface 300 may be contact | abutted. The pair of leg portions 5 extends downward from the lid member 4. Specifically, each leg 5 extends downward from both ends of the lid member 4 in the short direction. Each leg 5 extends to the placement surface 300 and is in contact with the placement surface 300.

  Each leg 5 extends downward from an edge extending in the longitudinal direction of the lid member 4, and each leg 5 extends in the longitudinal direction of the manifold 20. The length in the longitudinal direction (z-axis direction) of each leg 5 is not particularly limited, but is, for example, about 100 to 800 mm. Moreover, although the space | interval d of each leg part 5 and each 1st side wall 32 on the mounting surface 300 is not specifically limited, For example, it is about 5-50 mm. Each leg part 5 and the cover member 4 are comprised by one plate-shaped member. In this case, each leg part 5 is formed by bending the edge part of the transversal direction of the cover member 4 below. Note that the lid member 4 and each leg portion 5 are made of, for example, a metal having heat resistance. More specifically, the lid member 4 and each leg portion 5 are made of at least one selected from the group consisting of ferritic stainless steel, austenitic stainless steel, and Ni-based alloy.

  Each fuel cell 10 is supported on the manifold 20 configured as described above. Specifically, the lower end portion of each fuel cell 10 is inserted into each insertion hole 41 of the lid member 4. Note that both end portions 122 of each fuel cell 10 in the width direction may be placed on the first flange portion 322. The bonding material 101 is filled in the insertion hole 41 in the state where the fuel cell 10 is inserted.

The bonding material 101 is, for example, crystallized glass. As the crystallized glass, for example, a SiO ₂ —B ₂ O ₃ system, a SiO ₂ —CaO system, or a SiO ₂ —MgO system may be employed. In this specification, crystallized glass means that the ratio (crystallinity) of “volume occupied by crystal phase” to the total volume is 60% or more, and “volume occupied by amorphous phase and impurities relative to the total volume”. "Indicates a glass having a ratio of less than 40%. Note that amorphous glass, brazing material, ceramics, or the like may be employed as the material of the bonding material 101. Specifically, the bonding material 101 is at least one selected from the group consisting of SiO ₂ —MgO—B ₂ O ₅ —Al ₂ O ₃ and SiO ₂ —MgO—Al ₂ O ₃ —ZnO.

The fuel cell stack 100 configured as described above generates power as follows. A fuel gas (hydrogen gas or the like) is caused to flow into the gas flow path 121 of each fuel cell 10 through the manifold 20, and both surfaces of the support substrate 12 are exposed to a gas (air or the like) containing oxygen. An electromotive force is generated by a difference in oxygen partial pressure generated between the two side surfaces. When this fuel cell stack 100 is connected to an external load, an electrochemical reaction shown in the following formula (1) occurs in the air electrode 15, an electrochemical reaction shown in the following formula (2) occurs in the fuel electrode 13, and a current flows. .
(1/2) · O ₂ + 2e ⁻ → O ₂ ⁻ (1)
H ₂ + O ₂ ⁻ → H ₂ O + 2e ⁻ (2)

[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
In the above embodiment, each leg 5 is a plate-like member extending vertically downward from the lid member, but the structure of each leg 5 is not particularly limited thereto. For example, as shown in FIG. 6, the lower end portion of each leg portion 5 may have a contact portion 51 extending outward along the placement surface 300. As a result, the fuel cell stack 100 can be supported more stably.

  Moreover, as shown in FIG. 7, each leg part 5 may spread outward toward the downward direction. That is, each leg 5 may be inclined so as to be separated from the first side wall 32 downward. As a result, the fuel cell stack 100 can be supported more stably.

Modification 2
In the said embodiment, although each leg part 5 was extended below from the cover member 4, it is not specifically limited to this. For example, as shown in FIGS. 8 and 9, each leg 5 may extend downward from the first side wall 32. Specifically, each leg portion 5 extends downward from the first flange portion 322 of the first side wall 32. Each leg 5 and each first side wall 32 can be configured by one member. For example, each leg part 5 can be formed by bending the front-end | tip part of the 1st flange part 322 of each 1st side wall 32 below.

Modification 3
In the first modification, each leg portion 5 extends vertically downward from the first flange portion 322, but the structure of each leg portion 5 is not particularly limited thereto. For example, as shown in FIG. 10, the lower end part of each leg part 5 may have the contact part 51 extended outward. As a result, the fuel cell stack can be supported more stably.

  Moreover, as shown in FIG. 11, each leg part 5 may spread outward toward the downward direction. That is, each leg 5 may be inclined so as to be separated from the first side wall 32 downward. As a result, the fuel cell stack 100 can be supported more stably.

Modification 4
In the above embodiment, the fuel battery cell 10 is placed on the first flange portion 322, but the fuel battery cell 10 may not be placed on the first flange portion 322 as shown in FIG.

3: Manifold body 31: Bottom wall 32: First side wall 4: Cover member 41: Insertion hole 5: Leg 10: Fuel cell 20: Manifold 100: Fuel cell stack 300: Mounting surface

Claims (9)

A manifold for distributing gas to fuel cells,
A manifold body having a bottom wall placed on the placement surface and a pair of first side walls extending upward from each of a pair of edges extending in the longitudinal direction of the bottom wall;
A lid member that has an insertion hole into which a lower end portion of the fuel battery cell is inserted, and closes an upper surface of the manifold body;
A pair of legs arranged outside the first side walls and configured to contact the mounting surface;
A manifold. Each of the legs extends downward from the lid member.
The manifold according to claim 1. The manifold according to claim 2, wherein each of the leg portions and the lid member is constituted by one member. Each of the legs extends downward from the first side wall.
The manifold according to claim 1. Each said leg and each said 1st side wall are comprised by one member,
The manifold according to claim 4. Each of the first side walls includes a side wall main body portion extending upward from the bottom wall, and a flange portion extending outward from an upper end portion of the side wall main body portion,
The leg portion extends downward from the flange portion,
The manifold according to claim 4 or 5. Each of the leg portions has an abutting portion extending outward along the placement surface.
The manifold according to any one of claims 1 to 6. Each of the legs spread outwardly downward,
The manifold according to any one of claims 1 to 7. A manifold according to any of claims 1 to 8,
A fuel cell that has a lower end inserted into the insertion hole and extends upward from the lid member;
A fuel cell stack comprising:

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