Classifications

• • 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
  • H01M4/90—Selection of catalytic material
  • H01M4/9041—Metals or alloys
  • H01M4/905—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC
  • H01M4/9066—Metals or alloys specially used in fuel cell operating at high temperature, e.g. SOFC of metal-ceramic composites or mixtures, e.g. cermets
• • 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
  • H01M4/8605—Porous electrodes
• • 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
  • 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
  • H01M4/8889—Cosintering or cofiring of a catalytic active layer with another type of layer
• • 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
• • 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
  • H01M2008/1293—Fuel cells with solid oxide electrolytes

Definitions

• anode for a fuel cell in particular for a solid oxide fuel cell, which is formed at least substantially from a ceramic-metal composite material which is doped with at least one additive.
• the invention is based on an anode for a fuel cell, in particular for a solid oxide fuel cell, which is at least substantially formed by a ceramic-metal composite material which is doped with at least one additive.
• the additive has a specific surface area of at least 20 m 2 / g.
• a "fuel cell” is to be understood in this context as meaning, in particular, a device which is provided with at least one chemical reaction energy of at least one, in particular continuously supplied, fuel gas. in particular hydrogen and / or carbon monoxide, and at least one cathode gas, in particular oxygen, in particular into electrical and / or thermal energy to convert.
• a "ceramic-metallic composite material” is to be understood in particular as meaning a composite material, in particular a cermet, comprising at least one ceramic material. See material to be understood in a metallic matrix.
• a "ceramic material” is to be understood as meaning, in particular, an inorganic, nonmetallic material,
• the ceramic material may be at least partially crystalline and / or polycrystalline at least for the most part free of metal compounds based in particular on metallic bonds, but may include metal compounds such as metal oxides and / or silicates.
• the ceramic is a technical ceramics.
• the ceramic material is zirconium oxide, in particular a yttrium-stabilized zirconium oxide.
• the metallic matrix is formed, in particular, by a metallic material, preferably nickel.
• the anode is made of a mixture of nickel oxide and yttrium-stabilized zirconium oxide processed into a thin layer, in particular a printed layer and / or a cast film.
• pore formers, organic binders and / or further additives may be added to the mixture of nickel oxide and yttrium-stabilized zirconium oxide.
• the anode is sintered in a composite with at least one further functional layer of a fuel cell, for example a cathode and / or an electrolyte, as a fuel cell or as a half cell.
• the anode after sintering, has a structure with two intermeshing framework structures, one of which is formed by the yttrium-stabilized zirconium oxide and the second by the nickel oxide.
• a suitable pore structure within the composite may be present, generated either by suitable sintering parameters and / or by the addition of pore formers.
• the nickel oxide is converted into nickel at a high temperature, in particular at a temperature between 600 ° C. and 1000 ° C., under a reduced atmosphere.
• an "additive” is to be understood as meaning, in particular, a substance which is added to the composite material in particular for influencing material properties,
• the additive is intended for the composite material during production of the anode, in particular before and / or during a sintering process
• the additive is intended to influence a sintering behavior of the composite material
• the additive is intended, in particular, for a sintering behavior of the composite material of the anode, at least substantially to a sintering behavior of
• Fuel cell functional layers adapt, with which the anode during a Production is cogesinterert.
• the additive has a specific surface area of at least 20 m 2 / g, advantageously of at least 50 m 2 / g, particularly preferably of at least 100 m 2 / g.
• Such an embodiment can provide an anode with improved properties with regard to production, in particular with regard to co-sintering with further functional layers of a fuel cell.
• an advantageously good and / or uniform contact between the additive and the components, in particular nickel oxide and yttrium-stabilized zirconium oxide, of the composite material can be achieved. In this way it can be achieved that the effect of the additive already occurs at advantageously low concentrations.
• a content of the additive in the composite material is at most 1000 ppm, advantageously at most 750 ppm and particularly advantageously at most
• the content of the additive is at most 1000 ppm, based on the sum of the basic components of the composite material.
• the content of the additive is at most 1000 ppm, based on the sum of the masses of nickel oxide and yttrium-stabilized zirconium oxide in the composite material. Due to the low content of the additive, foreign phases within the
• Composite material advantageous at least largely avoided and negative effects of such foreign phases on the properties of the anode, for example, a reduction in the conductivity, advantageously be minimized. Furthermore, it is proposed that the additive be at least substantially
• Nanopowder is to be understood as meaning, in particular, a powder which has a particle size of at most 100 nm, preferably not more than 80 nm, advantageously not more than 50 nm and particularly preferably not more than 20 nm - Adhering large specific surface can be achieved.
• the additive is at least one metal oxide.
• a metal oxide is to be understood as meaning, in particular, an oxide of a metal, of a rare earth metal and / or of an alkaline earth metal. particular a sinter shrinkage of the composite, be favorably influenced.
• a method for producing an anode for a fuel cell, in particular for a solid oxide fuel cell made of a ceramic-metal composite material by means of sintering wherein the basic components of the composite material are mixed before sintering with an additive, which to adapt a sintering behavior of the composite material and which has a specific surface area of at least 20 m 2 / g.
• the additive is added to the composite prior to sintering of the composite.
• the basic components of the composite material in particular nickel oxide powder and powdery yttrium-stabilized zirconium oxide, are mixed together.
• additives for example pore formers, organic binders, solvents, plasticizers and / or further organic additives
• the mixture of the basic components of the additive is added.
• an amount of the additive is added to the basic components of the composite prior to sintering, which corresponds to a maximum of 1000 ppm based on the sum of the raw materials.
• the basic components of the composite and the additive are preferably mixed and / or homogenized prior to sintering to give a paste and / or a slurry.
• the mixture of the basic components of the composite material and the additive is processed into an anode layer and, in particular in combination with at least one further functional layer of a fuel cell, sintered.
• a fuel cell with at least one anode is proposed.
• the fuel cell is designed in particular as a solid oxide fuel cell (SOFC).
• the fuel cell has at least one cathode and at least one electrolyte arranged between the anode and the cathode.
• the electrolyte can consist at least essentially of yttrium-stabilized zirconium oxide, scandium-doped zirconium oxide, doped lanthanum gallate and / or gadolinium-doped cerium oxide.
• the anode may consist at least essentially of a cermet, preferably of a nickel-containing cermet, for example a Ni-ZrC cermet.
• the cathode can be used in particular at least substantially consist of an alkali-metal-bound manganate, for example LSM, an alkali-metal-divalent cobaltate, for example LSC, and / or a perovskite-like material, for example LSCF.
• an alkali-metal-bound manganate for example LSM
• an alkali-metal-divalent cobaltate for example LSC
• LSCF perovskite-like material
• the anode according to the invention and / or the method of production according to the invention should not be limited to the application and embodiment described above.
• the anode according to the invention and / or the method for performing a method of operation described herein may have a different number than a number of individual elements, components and units mentioned herein.
• Fig. 1 is a schematic representation of a functional layer package a
• Fuel cell with an anode of a composite material to which an additive is added
• FIG. 2 shows a flowchart of a method for producing the anode
• FIG. 3 shows a comparison of sintering curves of an anode without additive and a
• FIG. 1 shows a schematic representation of a functional layer package 16 of a fuel cell, not shown.
• the functional layer package 16 is applied to a particular ceramic carrier element 18.
• the carrier element 18 is in particular made porous.
• the functional layer package 16 has an anode 10, a cathode 20 and a disposed between the anode 10 and the cathode 20
• the functional layer package 16 is arranged with the cathode 20 directly on the carrier element 18.
• the electrolyte 38 consists in particular at least substantially of yttrium-stabilized zirconium oxide, scandium-doped zirconium oxide, doped lanthanum gallate and / or gallium-doped cerium oxide.
• the cathode 20 consists in particular at least substantially of an erdalkalidot convinced
• the anode 10 consists of a ceramic-metal composite material 12, in particular at least substantially of a cermet, preferably of a nickel-containing cermet, for example a Ni-ZrC cermet.
• the composite material 12 of the anode 10 is doped with an additive 14.
• the additive 14 has a specific surface area of at least 20 m 2 / g. A content of the additive 14 in the composite material 12 is at most 1000 ppm.
• the additive 14 is at least substantially a nanopowder added to the composite material 12 of the anode 10 during manufacture of the anode 10.
• the additive 14 is a metal oxide, preferably an aluminum oxide.
• FIG. 2 shows a flowchart of a method for producing the anode 10.
• a first method step 22 the basic components of the composite material 12 are weighed in and mixed.
• the basic components are each powdered.
• the nickel oxide has a specific surface area between 4 m 2 / g and 8 m 2 / g.
• the nickel oxide may have a specific surface area between 0.5 m 2 / g and 20 m 2 / g.
• the yttrium-stabilized zirconium oxide in particular has a specific surface between
• the yttria-stabilized zirconia may have a specific surface area between 0.5 m 2 / g and 30 m 2 / g.
• the yttrium-stabilized zirconium oxide consists in particular of zirconium oxide stabilized with 8 mol% Y 2 O 3.
• the zirconia may be present at 3 mole% to 12 mole%.
• a quantitative ratio between the nickel oxide and the yttrium-stabilized zirconium oxide is preferably between 65/35 mol% and 80/20 mol%.
• the basic components nickel oxide and yttrium-stabilized zirconium oxide can be mixed with other additives.
• Further additives may be, in particular, pore formers, for example flame black and / or PMMA beads, organic binders, for example polyvinyl butyral, ethyl cellulose, methyl cellulose and / or acrylates, solvents, for example water, alcohols and / or terpineol, plasticizers and / or further organic additives, For example, defoamer and / or wetting agents, be.
• an amount of the additive 14 which corresponds to a maximum of 1000 ppm based on the sum of the basic substances is added to the basic components of the composite material 12 before sintering.
• the additive 14 is added in particular in the form of a nanopowder.
• the additive 14 may be added in dissolved form.
• the additive 14 is preferably an alumina powder.
• other additives in particular other metal oxides, rare earth metal oxides and / or alkaline earth metal oxides may be added.
• the additive 14 has a specific surface area of at least 20 m 2 / g.
• the additive 14 may have a specific surface area between 20 m 2 / g and
• the basic components of the composite material 12 and the added additive 14 are mixed and / or homogenized in a further method step 26 prior to sintering to form a paste and / or a slurry.
• a further method step 26 prior to sintering to form a paste and / or a slurry.
• Basic components of the composite material 12 and the added additive 14 are first pre-homogenized in a planetary mixer or with a stirrer and then processed in a three-roll mill to a paste, which is suitable for screen printing, casting or other processes for the production of thin layers.
• a planetary mixer or with a stirrer can be used.
• other mixing units such as dissolvers and / or stirrer, can be used.
• the mixture of the basic components of the composite material 12 and the additive 14 is processed in particular by screen printing, film casting and / or dispensing to an anode layer and sintered at a temperature greater than 500 ° C.
• the reduction of the nickel oxide of the composite material 12 to nickel in a reducing atmosphere can be carried out in a further method step 30 or after being installed in a fuel cell stack.
• FIG. 3 shows in a diagram a comparison of a sintering curve 32 of an anode without doping by an additive and a sintering curve 34 of an anode 10 according to the invention.
• the sintering curves 32, 34 each show a percentage length change. tion 36 over the time 40 of the sintering process.
• the sintering curves 32, 34 show that even a doping amount of less than 1000 ppm of an additive 14 based on the sum of the basic components of the composite material 12 of the anode 10 is sufficient to significantly change the sintering behavior, in particular to significantly increase sintering shrinkage.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Ceramic Engineering (AREA)
• Composite Materials (AREA)
• Materials Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Inert Electrodes (AREA)
• Fuel Cell (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=60080775

Family Applications (1)

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Family Cites Families (11)

• 2016
  • 2016-11-24 DE DE102016223293.2A patent/DE102016223293A1/de active Pending
• 2017
  • 2017-10-04 JP JP2019527890A patent/JP7105772B2/ja active Active
  • 2017-10-04 WO PCT/EP2017/075198 patent/WO2018095631A1/de unknown
  • 2017-10-04 CN CN201780072550.6A patent/CN109964349A/zh active Pending
  • 2017-10-04 EP EP17783435.5A patent/EP3545578A1/de not_active Withdrawn

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