摘要:
An interconnect system including: a separator plate to provide an anode gas flow space; a first metal interconnect disposed between the separator plate and an anode surface; a nickel oxide paste applied in a pattern over the surface of the anode and adjacent surface of the separator plate which when sintered results in a first conductive layer bonded to the anode and the first interconnect, and a second conductive layer bonded to the first interconnect and the separator plate; a second metal interconnect disposed between a cathode surface of the cell and the separator plate of an adjacent cell cassette; and a silver-containing paste applied over the surface of the cathode and the separator plate which when sintered results in a third conductive layer bonded to the cathode and the second interconnect, and a fourth conductive layer bonded to the second interconnect and the separator plate.
摘要:
An interconnect system for connecting adjacent fuel cells in a fuel cell stack. The system comprises five elements: a separator plate to provide an anode gas flow space when joined to a mating cell frame; a first metal interconnect disposed between the separator plate and the anode surface; a nickel oxide paste applied in a pattern over the surface of the anode and adjacent surface of the separator plate which when sintered results in a conductive layer bonded to the anode and to the separator plate; a second metal interconnect disposed between the cathode surface of the cell and the separator plate of the adjacent cell cassette; and a silver-containing paste applied over the surface of the cathode and the separator plate which when sintered results in a conductive layer bonded to the cathode and to the separator plate.
摘要:
In assembling an SOFC fuel cell stack from a plurality of cassettes, the mounting plate of one cassette is attached to, and insulated from, the separator plate of the next-adjacent cassette by a peripheral dielectric seal consisting of a ceramic coating and a metal braze. Materials suitable for the ceramic coating include yttrium stabilized zirconia (YSZ), zirconia toughened alumina, magnesium silicates such as the mineral forsterite, magnesium aluminates, magnesium aluminosilicates and lanthanum zirconate. The ceramic coating may be applied to the cassette's outer surface in known fashion as by physical vapor deposition, chemical vapor deposition, sputtering, and various methods of plasma spray. An underlayer of alumina may also be used to provide a redundant layer of electrical insulation.
摘要:
An electrically-conductive mesh spacer incorporated into the hydrogen and air gas flow spaces between each anode and cathode and its adjacent interconnect in a fuel cell stack. The mesh is formed of metal strands and is formed into a predetermined three-dimensional pattern to make contact at a plurality of points on the surfaces of the electrode and the interconnect element. The formed mesh spacer is secured as by brazing to the interconnect element at a plurality of locations to form an interconnect, which preserves the pattern during assembly of a fuel cell stack. The height of the formed pattern is greater than the height of a gas flow space after fuel cell assembly, such that the mesh spacer is slightly compressed during assembly of a fuel cell stack. Because the metal mesh is both compliant and resilient, the compressed spacer is continuously urged into mechanical and electrical contact with its electrode over all temperatures and pressures to which the fuel cell assembly may be subjected during use.
摘要:
Nanocrystalline metal powders comprising tungsten, molybdenum, rhenium or niobium can be synthesized using a combustion reaction. Methods for synthesizing the nanocrystalline metal powders are characterized by forming a combustion synthesis solution by dissolving in water an oxidizer, a fuel, and a base-soluble, ammonium precursor of tungsten, molybdenum, rhenium, or niobium in amounts that yield a soichiometric burn when combusted. The combustion synthesis solution is then heated to a temperature sufficient to substantially remove water and to initiate a self-sustaining combustion reaction. The resulting powder can be subsequently reduced to metal form by heating in a reducing gas environment.
摘要:
A method for joining together two or more ceramic and/or metal parts by providing a braze consisting of a mixture of copper oxide, silver, and ceramic particulate. The braze is placed upon the surfaces of the parts, which are then held together for sufficient time and at a sufficient temperature to cause the braze to form a bond between the parts. The addition of the ceramic particulate increases the viscosity of the braze, decreasing squeeze out, decreasing the formation of air pockets, decreases the formation of brittle phases by providing nucleation sites and increases the flexural strength of the joint.
摘要:
A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.
摘要:
A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.
摘要:
A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.
摘要:
Nanocrystalline metal powders comprising tungsten, molybdenum, rhenium and/or niobium can be synthesized using a combustion reaction. Methods for synthesizing the nanocrystalline metal powders are characterized by forming a combustion synthesis solution by dissolving in water an oxidizer, a fuel, and a base-soluble, ammonium precursor of tungsten, molybdenum, rhenium, or niobium in amounts that yield a stoichiometric burn when combusted. The combustion synthesis solution is then heated to a temperature sufficient to substantially remove water and to initiate a self-sustaining combustion reaction. The resulting powder can be subsequently reduced to metal form by heating in a reducing gas environment.