WO2008050437A1 - Pile à combustible à oxyde solide - Google Patents

Pile à combustible à oxyde solide Download PDF

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Publication number
WO2008050437A1
WO2008050437A1 PCT/JP2006/321411 JP2006321411W WO2008050437A1 WO 2008050437 A1 WO2008050437 A1 WO 2008050437A1 JP 2006321411 W JP2006321411 W JP 2006321411W WO 2008050437 A1 WO2008050437 A1 WO 2008050437A1
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Prior art keywords
layer
oxide
fuel cell
solid electrolyte
cerium
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PCT/JP2006/321411
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English (en)
Japanese (ja)
Inventor
Akira Kawakami
Satoshi Matsuoka
Naoki Watanabe
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Toto Ltd.
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Priority to PCT/JP2006/321411 priority Critical patent/WO2008050437A1/fr
Priority to DE112006004086T priority patent/DE112006004086T5/de
Priority to CN2006800565918A priority patent/CN101558520B/zh
Publication of WO2008050437A1 publication Critical patent/WO2008050437A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H01M8/124—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte
    • H01M8/1246—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides
    • H01M8/126—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides the electrolyte containing cerium oxide
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/8647—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites
    • H01M4/8657—Inert electrodes with catalytic activity, e.g. for fuel cells consisting of more than one material, e.g. consisting of composites layered
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8878—Treatment steps after deposition of the catalytic active composition or after shaping of the electrode being free-standing body
    • H01M4/8882—Heat treatment, e.g. drying, baking
    • H01M4/8885—Sintering or firing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0065—Solid electrolytes
    • H01M2300/0068—Solid electrolytes inorganic
    • H01M2300/0071—Oxides
    • H01M2300/0074—Ion conductive at high temperature
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0088—Composites
    • H01M2300/0094—Composites in the form of layered products, e.g. coatings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to an electrode-supported solid oxide fuel cell having a lanthanum gallate oxide in a solid electrolyte layer, and in particular, by effectively preventing the influence of reaction between each layer,
  • the present invention relates to a solid oxide fuel cell having high output performance even at an operating temperature of about 800 ° C.
  • Lanthanum gallate oxide has been proposed as a solid electrolyte material for a low temperature operation type solid oxide fuel cell (see, for example, Patent Document 1 and Patent Document 2).
  • lanthanum gallate oxide is highly reactive with other materials, it reacts with the air electrode material and the fuel electrode material to form a high-resistance reaction product phase, which may reduce the power generation performance.
  • La Ce as a reaction suppression layer is interposed between the fuel electrode and a solid electrolyte layer made of lanthanum gallate oxide.
  • Non-Patent Document 1 It has been proposed to form a zero-strength layer (see Non-Patent Document 1, for example).
  • La Ce O is a material with extremely low sinterability, it was difficult to make the reaction suppression layer dense.
  • the fuel electrode and the solid electrolyte layer made of lanthanum gallate oxide reacted through the pores of the reaction suppression layer, and a high resistance reaction layer was formed at the interface.
  • the metal component contained in the support diffuses into the solid electrolyte layer.
  • Patent Document 1 Japanese Laid-Open Patent Publication No. 2002-15756 (Page 1-9, Fig. 1 to Fig. 9)
  • Patent Document 2 Japanese Patent Laid-Open No. 11-335164 (page 1-12, Fig. 1 to Fig. 12)
  • Patent Document 3 JP 2003-173802 (Page 1-7, Table 1)
  • Non-Patent Document 1 Electrochemical and Solid-State Letters, 7 (5) A105_A107 (2004) Disclosure of Invention
  • the present invention has been made to solve the above problems, and relates to a solid oxide fuel cell having a lanthanum gallate oxide in a solid electrolyte layer, and particularly, operates at about 600 ° C to 800 ° C. It is an object of the present invention to provide a solid oxide fuel cell having excellent power generation performance at a temperature.
  • the present invention provides a solid electrolyte layer between a fuel electrode and an air electrode.
  • One of the fuel electrode and the air electrode is a support, and the solid electrolyte layer includes a first layer and a second layer at least from the support side.
  • the first layer has the general formula Ce Ln 0 (where Ln is La, Pr, Nd, Sm, Eu, Gd, T
  • the layer comprises a lanthanum gallate oxide containing at least lanthanum and gallium, and the first layer contains a sintering aid capable of improving the sinterability of the cerium-containing oxide.
  • a solid oxide fuel cell characterized by 2 and T ⁇ 70 when the thickness of the layer is ⁇ m
  • the solid electrolyte layer comprises at least the first layer and the second layer from the support side, and the first layer is made of the cerium-containing oxide optimized for the doping amount of Ln.
  • the second layer is made of lanthanum gallate oxide, and the first layer contains a sintering aid that can improve the sinterability of the cerium-containing oxide.
  • it is / rn, it is 2 to 70, so a solid oxide fuel cell with excellent power generation performance can be provided.
  • the first layer made of a cerium-containing oxide containing a sintering aid is provided between the support and the second layer made of lanthanum gallate oxide.
  • This layer is densified, and the reaction between the support and the second layer made of lanthanum gallate oxide and the diffusion of the metal component from the support to the second layer can be effectively suppressed. Further, the densification of the first layer reduces the resistance loss in the first layer. Furthermore, since the composition of the cerium-containing oxide of the first layer is optimized, the reaction between the first layer and the second layer can be suppressed, so that power generation performance is improved.
  • the thickness of the second layer is reduced to the above range, the power loss is improved because the resistance loss in the solid electrolyte layer is small.
  • the first layer is dense and effectively suppresses the diffusion of the metal component from the support to the second layer, it is possible to prevent a short circuit between the electrodes even if the second layer is thinned. Therefore, the power generation performance will not deteriorate.
  • the thickness of the second layer is less than 2 zm, the first layer made of the cerium-containing oxide is reduced in the fuel atmosphere, so that electron conductivity is developed and the power generation performance is reduced. There is.
  • the thickness of the second layer in the solid electrolyte layer is It is characterized by 10 ⁇ T ⁇ 50 when m.
  • the thickness of the second layer is set to 10 ⁇ or more, whereby the first layer can be more reliably prevented from being reduced in the fuel atmosphere.
  • the thickness of the second layer is set to 50 ⁇ m or less, the resistance loss in the solid electrolyte layer becomes smaller.
  • a preferred embodiment of the present invention is characterized in that there are no inclusions between the first layer and the second layer in the solid electrolyte layer.
  • a preferred embodiment of the present invention is characterized in that the sintering aid force Ga element or B element contained in the first layer is contained.
  • the reason for this is that when a sintering aid containing Ga element or B element is added to the cerium-containing oxide, the sinterability of the cerium-containing oxide of the first layer is improved, and the first layer This is because of densification. As a result, the reaction between the support and the second layer can be effectively suppressed, and the resistance loss in the first layer is reduced, so that the power generation performance is improved.
  • a preferred embodiment of the present invention is characterized in that 0 ⁇ X ⁇ 5 when the content of Ga element contained in the first layer is Xwt%.
  • a preferred embodiment of the present invention is characterized in that 0 ⁇ Y ⁇ 2 when the content of B element contained in the first layer is Ywt%.
  • a preferred embodiment of the present invention is characterized in that when the thickness of the first layer is S ⁇ m, it is 5 to 50.
  • the thickness of the first layer is greater than 5 / im, so that the fuel electrode and the lanthanum gallate are This is because the reaction with the second layer made of an oxide can be prevented.
  • the thickness of the first layer is made thinner than 50 ⁇ , the effect of resistance loss in the first layer can be reduced.
  • the cerium-containing oxide in the first layer has the general formula Ce Ln 0 (where Ln is La and 0 ⁇ 30 ⁇ ⁇ 0 ⁇ 50).
  • a fuel electrode is used as a support, and the fuel electrode is doped with zirconium-containing oxide doped with Ni and / or NiO and one or more of CaO, Y0, Sc0.
  • Ni and / or NiO and Ce Ln 0 (where Ln is La, Pr, Nd, Sm, Eu, Gd, between the fuel electrode and the solid electrolyte layer) Tb, Dy, Ho, Er, Tm, Yb
  • An anode reaction catalyst layer in which any one or a combination of two or more of Lu, Sc, Y, and a cerium-containing oxide represented by 0.05 ⁇ y ⁇ 0.50) is uniformly mixed is provided.
  • the cerium-containing oxide contained in the fuel electrode reaction catalyst layer is 10 to 90 parts by weight.
  • the cerium-containing oxide has high oxygen ion conductivity and can also have electron conductivity in a reducing atmosphere, so that the reaction field of the formulas (1) and (2) is obtained. This is because the power generation performance is further improved because the three-phase interface is further increased and the reactions of the equations (1) and (2) can be performed more effectively.
  • the ratio of the cerium-containing oxide is out of the above range, the effect of providing the fuel electrode reaction catalyst layer is hardly seen.
  • the second layer comprising a lanthanum gallate oxide has the general formula La A Ga XZ 0 (where A is a Sr, Ca, Ba, or one or more of them) , X Is one or more of Mg, Al and In, Z is one or more of Co, Fe, Ni and Cu, 0 ⁇ a ⁇ 1, 0 ⁇ b ⁇ 1, 0 ⁇ It is characterized by being expressed by lanthanum gallate oxide expressed by c ⁇ 0.15).
  • the second layer of lanthanum gallate oxide has the general formula La Sr Ga Mg Co 0 (where 0.05 ⁇ a ⁇ 0.3, 0 ⁇ b ⁇ 0.3, 0 ⁇ c ⁇ 0.15)
  • a solid oxide fuel cell comprising a solid electrolyte layer between a fuel electrode and an air electrode, wherein one of the fuel electrode or the air electrode is a support, and the solid electrolyte layer is at least From the support side, it comprises a first layer and a second layer, and the first layer has the general formula Ce L lx n 0 (Ln is La, Pr, Nd, Sm, Eu, Gd, Tb , Dy, Ho, Er, Tm, Yb, Lu, Sc, Y
  • the layer contains a sintering aid capable of improving the sinterability of the cerium-containing oxide, and when the thickness of the second layer is Tm, 2 and T ⁇ 70. Therefore, it is possible to provide a solid oxide fuel cell with high output performance, particularly at an operating temperature of about 600 ° C. to 800 ° C.
  • FIG. 1 is a view showing a cross section of a unit cell in a solid oxide fuel cell of the present invention.
  • 1 is a fuel electrode support
  • 2 is a solid electrolyte layer
  • 2a is a first layer of the solid electrolyte layer
  • 2b is a second layer of the solid electrolyte layer
  • 3 is an air electrode.
  • FIG. 2 is a view showing a cross section of a solid oxide fuel cell using a fuel electrode produced in an example of the present invention as a support.
  • 1 is a fuel electrode support
  • 2 is a solid electrolyte layer
  • 2a is a first layer of the solid electrolyte layer
  • 2b is a second layer of the solid electrolyte layer
  • 3 is an air electrode
  • 4 is a fuel electrode reaction catalyst. Is a layer.
  • FIG. 3 is a view showing a cross section of a solid oxide fuel cell using an air electrode produced in an example of the present invention as a support.
  • 2 is a solid electrolyte layer
  • 2a is a first layer of the solid electrolyte layer
  • 2b is a second layer of the solid electrolyte layer
  • 4 is a fuel electrode reaction catalyst layer
  • 5 is an air electrode support
  • 6 is air.
  • the electrode reaction catalyst layer 7 is a fuel electrode.
  • FIG. 1 shows one embodiment of a cross section of a unit cell in a solid oxide fuel cell of the present invention, and shows a type using a fuel electrode as a support.
  • the solid oxide fuel cell according to the present invention includes, for example, a fuel electrode support 1 (for example, Ni and Z or NiO and Y 0 doped zirconium-containing oxide).
  • cerium-containing oxide represented by the first layer 2a for example, Ce La O (where 0.30 ⁇ x ⁇ 0.50) in the solid electrolyte layer 2 formed on the surface of the fuel electrode support.
  • the body electrolyte layer 2 includes a second layer 2b (ralanthanum gallate oxide) and an air electrode 3 (for example, lanthanum cobalt oxide or samarium cobalt oxide) formed on the surface of the solid electrolyte.
  • a second layer 2b (ralanthanum gallate oxide) and an air electrode 3 (for example, lanthanum cobalt oxide or samarium cobalt oxide) formed on the surface of the solid electrolyte.
  • the cerium-containing oxide of the first layer in the solid electrolyte layer according to the present invention has a general formula Ce Ln O () from the viewpoint of low reactivity with the second layer made of lanthanum gallate oxide.
  • Ln is La, and the one represented by 0.30 x x 0.50) is preferred.
  • the optimum doping amount of Ln is a force that varies within the above range depending on the composition of the lanthanum gallate oxide used in the second layer.
  • the lanthanum gallate oxide having a high oxygen ion conductivity in the second layer for example, the general formula La Sr Ga Mg Co O
  • the doping amount of Ln is more preferably 0.35 ⁇ x ⁇ 0.45.
  • the reactivity between the cerium-containing oxide and the lanthanum gallate oxide can be confirmed by the following method. That is, it can be confirmed by uniformly mixing the cerium-containing oxide powder and the lanthanum gallate oxide powder, followed by heat treatment at 1400 ° C., for example, and analyzing the crystal phase by X-ray diffraction.
  • Table 1 shows the crystalline phases identified by the X-ray diffraction method after the lanthanum gallate oxide powder and each cerium-containing oxide powder were uniformly mixed with each other in equal amounts and heat-treated at 1400 ° C. .
  • the composition of lanthanum gallate oxide was La Sr Ga Mg O.
  • the composition of the cerium-containing oxide is Ce La O (hereinafter abbreviated as LDC50), Ce La O (C
  • LDC40 0.5 0.5 2 0.6 0.4 2 or less abbreviated as LDC40
  • LDC30 Ce La O
  • LD Ce La O
  • C20 Ce La O (hereinafter abbreviated as LDC10), Ce SmO (hereinafter abbreviated as SDC20) Ce Sm 2 O (hereinafter abbreviated as SDC10), Ce Gd 2 O (hereinafter abbreviated as GDC 20)
  • the sintering aid added to the cerium-containing oxide of the first layer in the solid electrolyte layer according to the present invention improves the denseness of the first layer and reacts with surrounding materials. Those that are less affected by are preferred. As a result of various investigations on sintering aids, we have found that they are effective for Ga and B elements.
  • the Ga element source for example, gallium oxide (Ga 0) or a gallium compound that becomes Ga 0 during the firing step is preferable.
  • boric acid H BO
  • boron nitride BN
  • boron oxide B 0
  • boron compound which becomes B 0 is preferable.
  • the content of Ga element contained in the first layer is Xwt ° / in terms of oxide.
  • the first layer becomes more dense, so that the reaction between the support and the second layer can be effectively suppressed, and the resistance in the first layer can be reduced. This is because the loss is reduced.
  • a more preferable range of X is 0.3 to X 2.0. This is because, in addition to the above effect, the electrical conductivity of the cerium-containing oxide itself is improved, so that the resistance loss in the first layer is further reduced.
  • the content of B element contained in the first layer is Ywt% in terms of oxide, 0 ⁇ Y ⁇ 2 is preferable. This is because the resistance loss in the first layer is reduced by limiting to the above range.
  • the content of soot element is more preferably as small as possible within the above range.
  • the thickness of the first layer made of the cerium-containing oxide is S x m, it is preferably 5 to 50. Furthermore, it is more preferable that 10 ⁇ S ⁇ 40.
  • the thickness of the first layer is greater than 5 / im, so that the support and the lanthanum gallate are This is because the reaction with the second layer made of an oxide can be prevented, and the reaction can be prevented more reliably by setting it to 10 ⁇ or more.
  • the thickness of the first layer is preferably as thin as possible within a range that can sufficiently prevent the reaction between the support and the second layer made of lanthanum gallate oxide.
  • the lanthanum gallate oxide in the second layer of the solid electrolyte layer of the present invention has the general formula La Sr Ga Mg O (where 0.05 ⁇ a ⁇ 0.3 from the viewpoint of high oxygen ion conductivity). , 0 ⁇
  • LSGM b ⁇ 0.3
  • the lanthanum gallate oxide in the second layer of the solid electrolyte layer of the present invention has the general formula La Sr Ga Mg Co O (where 0.05 ⁇ a ⁇ from the viewpoint of high oxygen ion conductivity). 0.3
  • LSGMC 0 ⁇ b ⁇ 0.3, 0 ⁇ c ⁇ 0.15)
  • the second layer of the solid electrolyte layer in the present invention may include both a layer made of LSGM and a layer made of LSGMC. That is, it may have a multilayer structure of a layer made of LSGM and a layer made of LSGMC.
  • the second layer made of the lanthanum gallate oxide in the present invention is not accompanied by a significant decrease in oxygen ion conductivity, and is not affected by the reaction with surrounding materials, so that the sintering aid or the like can be used. Les that may contain additives.
  • the method for producing the cerium-containing oxide used for the first layer of the solid electrolyte layer and the lanthanum gallate oxide raw material powder used for the second layer in the present invention is not particularly limited.
  • the oxide mixing method, coprecipitation method, citrate method, spray pyrolysis method, sol-gel method, etc. are common.
  • the fuel electrode of the present invention is not particularly limited, but the electron conductivity is high in the fuel atmosphere of the solid oxide fuel cell (1), and the reaction of formula (2) is efficiently performed. I like it.
  • Preferred materials from these viewpoints include MO / dinoleconium-containing oxides, NiO / cerium-containing oxides, MO / lanthanum gallate oxides, and the like.
  • NiO / zirconium-containing oxide, NiO / cerium-containing oxide, and NiO / lanthanum gallate oxide are NiO and zirconium-containing oxide, NiO and cerium-containing oxide, and NiO, respectively.
  • lanthanum gallate oxide are uniformly mixed at a predetermined ratio.
  • the zirconium-containing oxide of the NiO / zirconium-containing oxide shown here refers to a zirconium-containing oxide doped with one or more of CaO, Y 0 and Sc 0, for example.
  • cerium-containing oxide of the NiO / cerium-containing oxide represented by the general formula Ce Ln 0 (however,
  • the lanthanum gallate oxide of the NiO / lanthanum gallate oxide shown here is not particularly limited, but is preferably LSGM or LSGMC in order to carry out the reactions of the formulas (1) and (2) more efficiently. Since MO is reduced to M in the fuel atmosphere, the mixture becomes M / zirconium-containing oxide, Ni / cerium-containing oxide, and Ni / lanthanum gallate oxide.
  • Uniformly mixed in the present specification means that raw material powder produced by an oxide mixing method, a coprecipitation method, a kennate method, a spray pyrolysis method, a sol-gel method, or the like is used. , You can get. In other words, the uniform mixing shown here indicates that the material level uniformity obtained by the above method is sufficiently uniform.
  • NiO / dinoleconium-containing oxides are preferable from the viewpoint of excellent strength as a support and high stability.
  • the reaction of the formulas (1) and (2) can be performed more efficiently, and from the viewpoint of improving the power generation performance, a fuel electrode reaction catalyst layer is provided between the fuel electrode and the solid electrolyte layer. It is preferable to provide it.
  • the fuel electrode reaction catalyst layer in the present invention include NiO / cerium-containing oxides and NiO / lanthanum gallate oxides from the viewpoint of excellent electron conductivity and oxygen ion conductivity. 10/90 to 90/10 are preferred. The reason for this is that the amount of NiO is less than 10/90 and the electron conductivity is too low.
  • the fuel electrode reaction catalyst layer may have a structure that is inclined so that the amount of NiO gradually increases from the solid electrolyte layer side toward the fuel electrode.
  • the fuel electrode and the fuel electrode reaction catalyst layer in the present invention may contain Fe, Co, Cu, Ru, Rh, Pd, Pt and the like in addition to Ni.
  • the air electrode of the present invention is not particularly limited, but lanthanum manganese-based oxides, lanthanum Ferrite oxides, lanthanum cobalt oxides, lanthanum nickel oxides, summary cobalt oxides, and the like can be used.
  • a lanthanum manganese-based oxide is preferable from the viewpoint of the stability of the material and the ease of securing pores during firing of the solid electrolyte layer.
  • La A MnO the values of d and e are in the range of 0.15 ⁇ d ⁇ 0.3 and 0.97 ⁇ e ⁇ l.
  • a in the general formula shown here is preferably Ca or Sr.
  • the lanthanum mangan oxide may be a solid solution of Ce, Sm, Gd, Pr, Nd, Co, Al, Fe, Cu, Ni or the like.
  • the air electrode reaction catalyst layer has, for example, the general formula La Sr Co Fe O (where 0.05 ⁇ m ⁇ 0.50, 0 ⁇ n ⁇ l) from the viewpoint of excellent electron conductivity and oxygen ion conductivity.
  • Lanthanum ferrite oxide and general formula Ce Ln 0 (where Ln is La, Pr, Nd, Sm, Eu, Gd,
  • One or a combination of two or more of Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, and Y, and a cerium-containing oxide represented by 0.05 ⁇ y ⁇ 0.50) is uniformly mixed.
  • a mixture in which the cerium-containing oxide is 10 to 90 parts by weight is preferable.
  • the lanthanum ferrite oxide has high electron conductivity and oxygen ion conductivity, and is further represented by the general formula Ce Ln 0 (where Ln is Li i y 2
  • the three-phase interface serving as the reaction field of the formula (3) is further increased, and the reaction of the formula (3) can be performed more efficiently. This is because the power generation performance is improved.
  • the ratio of the cerium-containing oxide contained in the air electrode reaction catalyst layer is less than 10 parts by weight, the sinterability of the air electrode reaction catalyst layer increases, so that the solid electrolyte layer and the fuel electrode During sintering, the fine structure of the air electrode reaction catalyst layer advances and power generation performance decreases. On the other hand, when it exceeds 90 parts by weight, the effect of providing the air electrode reaction catalyst layer is hardly seen.
  • the oxide mixing method, coprecipitation method, citrate method, spray pyrolysis method, sol-gel method, etc. are common.
  • the solid electrolyte layer in the present invention may have a configuration including a first layer, a second layer, and a third layer at least from the support side.
  • the third layer shown here has the general formula Ce Ln
  • Ln is less than La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, Y
  • the third layer it is possible to suppress the second layer made of lanthanum gallate oxide from reacting with both the air electrode and the fuel electrode.
  • the firing method for producing the solid electrolyte fuel cell according to the present invention by a sintering method is not particularly limited as long as a high output can be obtained. That is, a sequential firing method may be used, or a co-firing method in which at least two kinds, preferably all members are sintered at once, may be used. However, in consideration of mass productivity, the co-firing method is preferable because the man-hour is reduced.
  • the co-firing for example, a step of producing a molded body of a fuel electrode or air electrode support and calcining at 800 ° C to 1200 ° C, and a solid electrolyte on the surface of the obtained calcined body Forming a layer and co-sintering with the support at 120 ° C to 1400 ° C, and forming the other electrode on the surface of the sintered solid electrolyte layer and sintering at 800 ° C to 1200 ° C
  • a cell manufacturing method comprising the steps.
  • the sintering temperature during co-firing of the support and electrolyte is 1250 ° C to 1350 ° C from the viewpoint of suppressing the diffusion of metal components from the support and obtaining a solid electrolyte layer having no gas permeability. More preferred.
  • a slurry coating method a tape casting method, a doctor blade method, a screen printing method, an EVD method, a CVD method, an RF sputtering method and the like are not particularly limited.
  • the slurry coating method is preferred from the viewpoint of excellent mass productivity that can be produced and low cost.
  • the shape of the solid electrolyte fuel cell in the present invention is not particularly limited, and may be either a flat plate type or a cylindrical type, for example, a microtube type (outer diameter 10 mm or less, more preferably 5 mm or less). Applicable. By the way, the effect of the present invention is that excellent power generation performance is obtained particularly at an operating temperature of about 600 ° C to 800 ° C.
  • Solid oxide The low temperature operation of the fuel cell is preferable from the viewpoint of startability of the solid oxide fuel cell. From the viewpoint of reliability and stability with respect to rapid start-up and rapid stop, the solid oxide fuel cell is preferably cylindrical.
  • cerium-containing oxide and the lanthanum gallate oxide in the present specification have oxygen deficiency related to the amount and type of the added caro atoms, and therefore, precisely, the general formula Ce Ln
  • cerium-containing oxide and lanthanum gallate oxide in this specification are represented by the general formulas Ce Ln O and La A Ga X O for convenience.
  • a press body was prepared and examined for the sintering aid to be added to the cerium-containing oxide of the first layer in the solid electrolyte layer.
  • LDC40 powder was used as the cerium-containing oxide.
  • Ga 0 powder is used as a sintering aid containing B element.
  • H BO powder or BN powder are used, both of which meet the conditions in Table 2 in terms of oxide.
  • a mixed powder was prepared by mixing with LDC40 powder. The mixing was performed with a wet ball mill. After adding a binder to the obtained mixed powder, uniaxial press molding was performed to produce a pressed body. The pressed body was fired at a predetermined temperature shown in Table 2. The relative density of the obtained sintered body was measured by the Archimedes method. The obtained sintered body was polished to a thickness of 1 mm, and then a platinum paste was applied, a platinum wire was attached, and baked at 1000 ° C. The electrical conductivity of the pellet was measured using the AC impedance method for the prepared sample.
  • Table 2 shows the results of relative density and electrical conductivity after sintering of each pellet.
  • Figure 2 shows the configuration of a solid oxide fuel cell using the fabricated fuel electrode as a support. That is, it is composed of a solid electrolyte layer 2 formed on the outside of the fuel electrode support 1 and an air electrode 3 formed on the outside of the solid electrolyte layer 2.
  • the fuel electrode support 1 and the solid electrolyte An anode reaction catalyst layer 4 is provided between the layers 2.
  • the solid electrolyte layer 2 includes a first layer 2a and a second layer 2b. The production procedure is shown below.
  • a mixture of NiO powder and (ZrO 2) (Y 0) (hereinafter abbreviated as YSZ) powder was prepared by a wet mixing method, followed by heat treatment and pulverization to obtain a fuel electrode support raw material powder.
  • the mixing ratio of MO powder and YSZ powder was 65/35 by weight.
  • a cylindrical molded body was produced from the powder by an extrusion molding method. The molded body was heat treated at 900 ° C. to obtain a calcined body. On the surface of the calcined body, a fuel electrode reaction catalyst layer, a first layer in a solid electrolyte layer, and a second layer were formed in this order by a slurry coating method.
  • the thickness of the first layer in the solid electrolyte layer was adjusted to the film thickness shown in Table 3, respectively.
  • the thickness of the second layer of the solid electrolyte layer was also adjusted to the thickness shown in Table 3.
  • the cell was masked so that the area of the air electrode was 17.3 cm 2 , the air electrode was formed on the surface of the solid electrolyte layer by a slurry coating method, and fired at 1100 ° C.
  • the fuel electrode support had dimensions after co-firing, an outer diameter of 5 mm, a wall thickness of 1 mm, and an effective cell length of 110 mm.
  • the details of the slurry preparation method for each layer used in the slurry coating method are shown in (1-a) to (1_d) below.
  • a mixture of NiO powder and GDC10 powder was prepared by a coprecipitation method, and then heat-treated to obtain a fuel electrode reaction catalyst layer powder.
  • the mixing ratio of NiO powder and GDC10 powder was 50/50 by weight.
  • the average particle size was adjusted to 0.5 ⁇ m. 40 parts by weight of the powder 100 parts by weight of solvent (ethanol), 2 parts by weight of binder (ethyl cellulose), 1 part by weight of dispersant (polyoxyethylene alkyl phosphate ester), 1 part by weight of antifoaming agent (sorbitan sesquilate) Then, the mixture was sufficiently stirred to prepare a slurry.
  • LSGM powder having a composition of La Sr Ga Mg O was used as the material for the second layer. 40 parts by weight of LSGM powder 100 parts by weight of solvent (ethanol) 2 parts by weight of binder (ethyl cellulose) 1 part by weight of dispersant (polyoxyethylene alkyl phosphate) 1 part by weight of antifoaming agent (sorbitan sesquilate) Then, the mixture was sufficiently stirred to prepare a slurry.
  • solvent ethanol
  • binder ethyl cellulose
  • dispersant polyoxyethylene alkyl phosphate
  • antifoaming agent sorbitan sesquilate
  • a powder having a composition of La Sr Co Fe O was used as the material for the air electrode. 40 parts by weight of the powder: 100 parts by weight of a solvent (ethanol), 2 parts by weight of a binder (ethyl cellulose), 1 part by weight of a dispersant (polyoxyethylene alkyl phosphate), an antifoaming agent (sorbitan sesquilate)
  • a solvent ethanol
  • a binder ethyl cellulose
  • a dispersant polyoxyethylene alkyl phosphate
  • an antifoaming agent sorbitan sesquilate
  • the slurry was prepared by sufficiently stirring.
  • the sintering aid to be added to the first layer of the solid electrolyte layer is H3 B03 powder, and a cell of a type in which 0.5 wt% is added to the LDC40 powder in terms of oxide. was also produced in the same manner.
  • the sintering aid added to the first layer of the solid electrolyte layer is BN powder and is converted into oxide.
  • a cell of the type in which 0.5 wt% was added to LDC40 powder was also prepared in the same manner.
  • a cell of the type without the sintering aid added to the first layer of the solid electrolyte layer was also prepared in the same manner.
  • a cell of the type using GDC10 was prepared in the same manner.
  • a cell of the type using LDC10 was produced in the same manner.
  • a power generation test was performed using the obtained fuel electrode support cell (electrode effective area: 17.3 cm 2 ).
  • the current collection on the fuel electrode side was performed by applying a silver paste to the entire inner surface of the fuel electrode support and then baking the silver mesh.
  • Current collection on the air electrode side was also performed by applying a silver paste, cutting the silver mesh into strips, winding them in a spiral, and baking them.
  • the fuel was a mixed gas of (H + 3% H 0) and N.
  • the fuel utilization rate was 10%.
  • the oxidizing agent was air. Measurement temperature was 600 D C, it was measured power generation potential at m 2 N current density 0.125 A.
  • Table 3 shows the results obtained from the power generation test of the cell with the fuel electrode as the support.
  • the “X” in Table 3 indicates the case where the generated potential is 0.5V or less. It was confirmed that excellent power generation performance can be obtained with the configuration proposed in the present invention. That is, when comparing cell No. 3 and cell N 0.11, the addition of a sintering aid to the first layer improves the denseness of the first layer, and the first layer consisting of the support and the lanthanum gallate oxide. It was confirmed that the power generation performance was improved because the reaction with the metal layer could be suppressed and the diffusion of the metal component from the support could be effectively prevented. In addition, when comparing cell No. 3 with cell Nos.
  • Figure 3 shows the configuration of a solid oxide fuel cell using the fabricated air electrode as a support.
  • it is composed of a solid electrolyte layer 2 formed outside the air electrode support 5 and a fuel electrode 7 formed outside the solid electrolyte layer 2, and the air electrode support 5 and the solid electrolyte.
  • an air electrode reaction catalyst layer 6 is provided between the layer 2 .
  • a fuel electrode reaction catalyst layer 4 is provided between the solid electrolyte layer 2 and the fuel electrode 7.
  • the solid electrolyte layer 2 includes a first layer 2a and a second layer 2b. The production procedure is shown below.
  • the air electrode support As a material for the air electrode support, a powder of La Sr MnO composition was used, and a cylindrical molded body was produced by an extrusion molding method. Further, firing was performed at 1500 ° C. to obtain an air electrode support.
  • the air electrode support had an outer diameter of 5 mm, a wall thickness of 1 mm, and an effective cell length of 110 mm.
  • the air electrode reaction catalyst layer is made of La Sr Co Fe O (hereinafter abbreviated as LSCF) powder and
  • LSCF / GDC10 in which GDC10 powder was uniformly mixed was used.
  • the weight ratio between LSCF and GDC10 was 50/50.
  • each was prepared by a coprecipitation method, mixed in ethanol using zirconia balls, subjected to heat treatment, and pulverized again using zirconia balls to adjust the particle size.
  • the average particle size at this time was 5 zm.
  • the air electrode reaction catalyst layer powder 100 parts by weight of solvent (ethanol), 2 parts by weight of binder (ethyl cellulose), 1 part by weight of dispersant (polyoxyethylene alkyl phosphate ester), antifoaming agent (sorbita After mixing 1 part by weight of sesquicholate), the mixture was sufficiently stirred to prepare a slurry. Using this slurry, a film was formed on the air electrode support by a slurry coating method and sintered at 1400 ° C. The thickness of the air electrode reaction catalyst layer was 15 zm.
  • the slurry prepared in section (1-b) was used, and a film was formed on the surface of the air electrode catalyst layer by a slurry coating method, and sintered at 1430 ° C. to form a first layer of solid electrolyte. .
  • the thickness of the first layer was 10 zm.
  • the material for the fuel electrode catalyst layer was NiO / Ce Sm 2 O (hereinafter abbreviated as MO / SDC20), and after preparation by a coprecipitation method, heat treatment was performed and the particle diameter was controlled to obtain a raw material powder.
  • MO / SDC20 weight ratios 30/70 and 50/50 were prepared. Both powders had an average particle size of 0.5 ⁇ .
  • the material for the fuel electrode was MO / SDC20, prepared by co-precipitation method, then heat-treated, and the particle size was controlled to obtain raw material powder.
  • the weight ratio of MO / SDC20 was 70/30.
  • the particle size of the powder was 1.5 / m. 100 parts by weight of the powder, 500 parts by weight of an organic solvent (ethanol), 20 parts by weight of a binder (ethyl cellulose), 5 parts by weight of a dispersant (polyoxyethylene alkyl phosphate ester), an antifoaming agent (sorbitan sesquilate) 1
  • a plasticizer DBP
  • the slurry was prepared by sufficiently stirring.
  • a fuel electrode was formed on the fuel electrode reaction catalyst layer by a slurry coating method. The thickness of the fuel electrode (after firing) was 90 ⁇ m.
  • the anode reaction catalyst layer and the anode were sintered together at 1300 ° C.
  • a cell of the type using GDC10 as the cerium-containing oxide used for the first layer of the solid electrolyte layer was prepared in the same manner.
  • a power generation test was performed using the obtained air electrode support cell (electrode area: 17.3 cm 2 ).
  • Sky The current collector on the air electrode side was obtained by applying a silver paste to the entire inner surface of the air electrode support and then baking the silver mesh.
  • Current collection on the fuel electrode side was performed by applying Ni paste, cutting the Ni mesh into strips and winding them in a spiral.
  • the fuel was a mixed gas of (H + 3% H 0) and N 2.
  • the fuel utilization rate was 10%.
  • the oxidant was air and the air utilization rate was 20%.
  • the power generation potential was measured at a measurement temperature of 600 ° C and a current density of 0.125Am.
  • Table 4 shows the results obtained by the power generation test of the cell using the air electrode as a support. It was confirmed that excellent power generation performance can be obtained with the configuration proposed in the present invention.

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Abstract

L'invention concerne une pile à combustible à oxyde solide particulièrement performante, notamment à des températures de fonctionnement comprises entre environ 600 et 800°C, du fait de l'absence d'interaction entre ses couches constitutives. La pile à combustible à oxyde solide comprend une électrode à combustible et une électrode à air entre lesquelles est disposée une couche d'électrolyte solide. L'électrode à combustible ou l'électrode à air sert de support et la pile à combustible à oxyde solide comprend au moins une première couche et une deuxième couche disposées dans cet ordre du côté de l'électrode formant support. La pile à combustible à oxyde solide est caractérisée en ce que la première couche comprend un oxyde contenant du cérium et la deuxième couche comprend un oxyde à base de gallate de lanthane contenant du lanthane et du gallium, en ce que la première couche contient un auxiliaire de frittage destiné à améliorer l'aptitude au frittage de l'oxyde contenant du cérium, et en ce que l'épaisseur T de la deuxième couche exprimée en mm vérifie les inégalités suivantes : 2 < T < 70.
PCT/JP2006/321411 2006-10-26 2006-10-26 Pile à combustible à oxyde solide WO2008050437A1 (fr)

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PCT/JP2006/321411 WO2008050437A1 (fr) 2006-10-26 2006-10-26 Pile à combustible à oxyde solide
DE112006004086T DE112006004086T5 (de) 2006-10-26 2006-10-26 Festoxid-Brennstoffzelle
CN2006800565918A CN101558520B (zh) 2006-10-26 2006-10-26 固体氧化物型燃料电池

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JP2012156107A (ja) * 2011-01-28 2012-08-16 Kyocera Corp 固体酸化物形燃料電池セル
WO2015004237A1 (fr) * 2013-07-10 2015-01-15 Danmarks Tekniske Universitet Hétérostructure à film mince stabilisée destinée à des applications électrochimiques

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JP6156778B2 (ja) * 2012-09-28 2017-07-05 Toto株式会社 固体酸化物形燃料電池セル
US10529975B2 (en) * 2014-12-15 2020-01-07 West Virginia University Nanoscale SOFC electrode architecture engineered using atomic layer deposition

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JP2005108719A (ja) * 2003-09-30 2005-04-21 Toto Ltd 固体酸化物型燃料電池
JP2005310737A (ja) * 2004-03-23 2005-11-04 Toto Ltd 固体酸化物形燃料電池
JP2006073231A (ja) * 2004-08-31 2006-03-16 Kyocera Corp 燃料電池セル
JP2006073230A (ja) * 2004-08-31 2006-03-16 Kyocera Corp 燃料電池セル
JP2006127821A (ja) * 2004-10-27 2006-05-18 Toto Ltd 固体酸化物形燃料電池セルおよび固体酸化物形燃料電池
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Publication number Priority date Publication date Assignee Title
JP2012156107A (ja) * 2011-01-28 2012-08-16 Kyocera Corp 固体酸化物形燃料電池セル
WO2015004237A1 (fr) * 2013-07-10 2015-01-15 Danmarks Tekniske Universitet Hétérostructure à film mince stabilisée destinée à des applications électrochimiques

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