Abstract:
A fuel cell device with a rectangular solid ceramic substrate extending in length between first and second end surfaces where thermal expansion occurs primarily along the length. An active structure internal to the exterior surface extends along only a first portion of the length and has an anode, cathode and electrolyte therebetween. The first portion is heated to generate a fuel cell reaction. A remaining portion of the length is a non-heated, non-active section lacking opposing anode and cathode where heat dissipates along the remaining portion away from the first portion. A second portion of the length in the remaining portion is distanced away from the first portion such that its exterior surface is at low temperature when the first portion is heated. The anode and cathode have electrical pathways extending from the internal active structure to the exterior surface in the second portion for electrical connection at low temperature.
Abstract:
The invention provides solid oxide fuel cell devices and systems, each including an elongate substrate having an active end region for heating to an operating reaction temperature, and a non-active end region that remains at a low temperature below the operating reaction temperature when the active end region is heated. An electrolyte is disposed between anodes and cathodes in the active end region, and the anodes and cathodes each have an electrical pathway extending to an exterior surface in the non-active end region for electrical connection at low temperature. The system further includes the devices positioned with their active end regions in a hot zone chamber and their non-active end regions extending outside the chamber. A heat source is coupled to the chamber to heat the active end regions to the operating reaction temperature, and fuel and air supplies are coupled to the substrates in the non-active end regions.
Abstract:
A fuel cell device is prepared by dispensing and drying electrode and ceramic pastes around two pluralities of removable physical structures to form electrode layers having constant width and a shape that conforms lengthwise to a curvature of the physical structures. An electrolyte ceramic layer is positioned between electrode layers, forming an active cell portion where anode is in opposing relation to cathode with electrolyte therebetween, and passive cell portions where ceramic is adjacent the active cell portion. The layers are laminated, the physical structures pulled out, and the lamination sintered to form an active cell with active passages in anodes and cathodes and passive support structure with passive passages in ceramic. End portions of at least one of the two pluralities of physical structures are curved away from the same end portion of the other of the two pluralities resulting in a split end in the fuel cell device.
Abstract:
An active cell is prepared by dispensing first electrode sub-layers, pressing in physical structures to partially embed them in an uppermost sub-layer, and dispensing more first electrode sub-layers wherein dispensing is in order of increasing porosity, then drying the sub-layers to form a first electrode layer. An electrolyte layer is then formed thereon. Further preparation includes dispensing second electrode sub-layers over the electrolyte layer, pressing in physical structures to partially embed them in an uppermost sub-layer, and dispensing more second electrode sub-layers wherein dispensing is in order of decreasing porosity, then drying the sub-layers to form a second electrode layer. A laminated stack is formed, then the physical structures are pulled out. Sintering then forms the active cell with active passages embedded in and supported by the sintered electrode layers, and with decreasing porosity in the electrode layers in a thickness direction away from the electrolyte layer.
Abstract:
A single monolithic ceramic substrate has rectangular dimensions with thermal expansion dominant along the length. An inactive ceramic portion substantially surrounds a fuel cell active portion of scalable power. The active portion comprises a plurality of three-layer active structures, each including an electrolyte disposed between a first polarity electrode and a second polarity electrode, the electrolyte layers being co-fired with the inactive ceramic portion, and a first or second gas passage respectively associated with each first and second polarity electrode. The plurality of active structures are stacked in the thickness dimension with alternating polarity such that first polarity electrodes of adjacent active structures face each other with the associated first gas passage shared therebetween and second polarity electrodes of adjacent active structures face each other with the associated second gas passage shared therebetween. The power is scalable according to the number of active structures stacked to define the plurality.
Abstract:
A fuel cell device is provided having an active structure with an anode and cathode in opposing relation with an electrolyte therebetween, a fuel passage adjacent the anode for supplying fuel to the active structure, and an air passage adjacent the cathode for supplying air to the active structure. A porous ceramic layer is positioned between each of the anode and fuel passage and the cathode and air passage, the porous ceramic layers having a porosity configured to permit transport of fuel and air from the respective fuel and air passage to the respective anode and cathode. An inactive surrounding support structure is provided that is monolithic with the electrolyte and the porous ceramic layers, wherein the inactive surrounding support structure lacks the anode and cathode in opposing relation and the active structure resides within the inactive surrounding support structure.
Abstract:
Fuel cell devices are provided having improved shrinkage properties between the active and non-active structures by modifying the material composition of the non-active structure, having a non-conductive, insulating barrier layer between the active structure and surface conductors that extend over the inactive surrounding support structure, having the width of one or both electrodes progressively change along the length, or having a porous ceramic layer between the anode and fuel passage and between the cathode and air passage. Another fuel cell device is provided having an internal multilayer active structure with electrodes alternating in polarity from top to bottom and external conductors on the top and/or bottom surface with sympathetic polarity to the respective top and bottom electrodes. A fuel cell system is provided with a fuel cell device having an enlarged attachment surface at one or both ends, which resides outside the system's heat source, insulated therefrom.
Abstract:
An electrode layer is provided by forming first and second sublayers containing input passages and exhaust passages, respectively. Electrode material is positioned around a first portion of first and second pluralities of spaced-apart removable physical structures to at least partially surround the structures thereby forming an active cell portion in each sublayer. Ceramic material is positioned around second portions to form a passive support structure in each sublayer. Another passive support structure is formed opposite the first, with the active cell portion therebetween. The sublayers are laminated, the physical structures are pulled out, and the laminated sublayers are sintered to reveal spaced-apart input passages from one end of the layer through the active cell portion, and spaced-apart exhaust passages from the active cell portion to a side of the layer adjacent the other end, the input and exhaust passages embedded in and supported by the sintered electrode and ceramic materials.
Abstract:
Fuel cell devices and systems are provided. A reaction zone positioned along a portion of the length is configured to be heated to an operating reaction temperature, and has at least one active layer therein comprising an electrolyte separating an anode from an opposing cathode, and fuel and oxidizer gas passages adjacent the respective anode and cathode. At least one cold zone positioned from the first end along another portion of the length is configured to remain below the operating reaction temperature. The anode and cathode each have electrical pathways extending to an exterior surface in the cold zone for electrical connection at the lower temperature. The electrolyte includes at least a portion thereof comprising a ceramic material sintered from a nano-sized powder. In one embodiment, the sintered nano-sized powder provides an uneven surface topography on the electrolyte.
Abstract:
A multilayer ceramic capacitor, having a plurality of electrode layers and a plurality of substantially titanium dioxide dielectric layers, wherein each respective titanium dioxide dielectric layer is substantially free of porosity, wherein each respective substantially titanium dioxide dielectric layer is positioned between two respective electrode layers, wherein each respective substantially titanium dioxide dielectric layer has an average grain size of between about 200 and about 400 nanometers, wherein each respective substantially titanium dioxide dielectric layer has maximum particle size of less than about 500 nanometers. Typically, each respective substantially titanium dioxide dielectric layer further includes at least one dopant selected from the group including P, V, Nb, Ta, Mo, W, and combinations thereof, and the included dopant is typically present in amounts of less than about 0.01 atomic percent.