Abstract: A semi-internally manifolded interconnect structured for placement between successive electrolyte elements in stack of elements having a first surface with a level margin extending substantially around the perimeter of the interconnect, first and second manifold channels disposed inward from the margin, and a plurality of gas-flow channels disposed in a central area of the first surface and extending between and in fluid communication with the first and second manifold channels.

Abstract: A thermally integrated reformer (10) is located inside the stack furnace (12), housing stacks (14) of solid oxide fuel cells (16). The energy to support the endothermic reformation reaction converting hydrocarbon and water feedstock into hydrogen and carbon monoxide fuel is supplied by heat recuperated from the oxidation process in the stack (14) of fuel cells (16). The source of hydrocarbons is de-sulfurized natural gas. Heat transfers to the incrementally shielded packed beds (30, 60) of the reactors (18, 19) of the reformer (10) by radiation from the stacks (14) and furnace wall (38) and by forced convection from the exhausting airflow exiting the stack furnace (12). Temperature gradients in the reformer (10) are controlled by selective (or incremented) radiation shielding (20) and by counterflow heat exchange to prevent excessive premature cracking in the reformer where carbonization would clog interstices and render the catalyst granules (32) ineffective.

Abstract: A thermally integrated heat exchange system for solid oxide electrolyte systems includes a thermally insulated furnace enclosure structure having an internal chamber therein and a plurality of solid oxide electrolyte plates disposed within the internal chamber. A heat exchanger particularly suited for use with the thermally integrated system has gas passageways for the flow of gases therethrough and is associated with the walls of the furnace enclosure. Thermal energy radiated from an operational solid oxide electrolyte system within the furnace enclosure may be used to preheat incoming reactant gases destined for use by the electrolyte plates. Exchange of thermal energy between hot exhaust gases and cooler incoming gases may also occur in the heat exchanger gas passageways that are substantially thermally integrated along their length.

Abstract: A porous, creep-resistant, metal-coated, LiFeO.sub.2 ceramic electrode for fuel cells is disclosed. The electrode is particularly useful for molten carbonate fuel cells (MCFC) although it may have utilities in solid oxide fuel cells (SOFC) as well.

Abstract: An electrochemical device is disclosed comprising a plurality of electrolytic cells, each having an oxygen ion-conducting electrolyte, an anode and a cathode associated with the electrolyte, conductive interconnecting structures electrically connecting the anode of each electrolytic cell to the cathode of an adjacent tubular cell, and sealing means positioned between the interconnecting structure and the electrolytic cells to provide a gas-tight seal therebetween. The configuration of the interconnecting structure and the placement of the seal means provides a separation between the seal and the conductive pathway of electrons between the anode and cathode to prevent corrosion or deterioration of the seal thereby compromising the pneumatic integrity of the device.

Abstract: An ion conducting device having a plurality of solid electrolyte plates arranged into a stack, each electrolyte plate having electrode material adherent to a significant portion thereof. A plurality of individual spacers are disposed between adjacent electrolyte plates in the stack, each spacer spacing successive electrolyte plates apart, and defining a plurality of chambers in the spaces between adjacent electrolyte plates. The electrode material on the electrolyte plates is electrically connected whereby electrode material on every other successive plate is connected in series, from one end of the stack to the other, whereupon the electrical path wraps around the stack and extends back along the stack and connects in series the electrodes not previously connected.

Abstract: A electrolytic cell for efficiently producing caustic from sodium salts via use of a thin membrane of ceramic or ceramic composite electrolyte is disclosed. Ceramic electrolytes having a very mobile sodium ion such as NASICON are very effective in cells producing concentrated caustic from sodium salts of strong acids.

Abstract: A sodium ion sensor having a composite electrolyte is disclosed. The sodium ion sensor has an outer electrolyte which is insensitive to water and has a high transport activity for sodium ions and an inner electrolyte which is a thin membrane having a very high sodium ion selectivity. The sodium ion sensor having such an electrolyte is sensitive only to the transport of sodium ions and may be operated in aqueous solutions without buffering and in the presence of other alkali ions and alkaline earth metal ions. Sensors of this type operate in EMF mode to give a substantially instantaneous determination of the sodium ion concentration of the aqueous medium being analyzed. The sensor may be used as an on-line sensor directly exposed to the medium to be analyzed.

Abstract: The invention is a ceramic solid electrolyte based electrochemical oxygen concentrator cell and the method for fabricating said cell. The cell is based on a doped cerium oxide ceramic solid electrolyte and lanthanum strontium cobaltite ceramic electrodes.

Abstract: An improved high temperature electrochemical cell employing a molten alkali metal anolyte, a solid ceramic electrolyte containing mobile alkali metal ions, and a molten sulfur/selenium catholyte is disclosed.

Abstract: High surface area, submicron ceramic powders are synthesized by reducing an oxide in the presence of another metal (i.e., Mg, Al, Ca, and the like) and a source of carbon, nitrogen or boron to form a new oxide and a carbide, nitride (or carbonitride). or boride. The oxide phase can be leached out to leave submicron carbides, nitrides or borides. Alternatively milling of reacted powders allows intimate mixtures of uniform, fine grained ceramic powders to be prepared inexpensively. These multiple-phase composite powders can be formed into a body and densified using conventional techniques to form dense, fine-grained ceramic bodies. Alternatively, containment of unreacted powders and subsequent heating results in multiple-phase dense ceramics with unique microstures. Transformation toughening of composites is possible by adding zirconia or hafnia either before or after the powder synthesis step.

Abstract: An electrochemical oxygen generating device employing oxygen-conducting metal oxide electrolyte, a non-porous silver or silver alloy containing electrode and an electrode undercoat comprising a ceramic oxide electronic conductor is disclosed.

Abstract: Ceramic bodies having a balanced overall stress pattern in which are present individual stress zones of compressive and tensile stresses and the techniques for forming said bodies are disclosed. The bodies are formed by having slightly different compositional patterns from one zone to another whereby during cooling there is a differential volumetric expansion or contraction in one zone as compared to an adjacent zone. The volumetric expansion or contraction is caused by a material which undergoes a phase transformation during the cooling from the sintering temperatures utilized to sinter the ceramic body, whereby such phase transformation is accompanied by a volumetric change.

Abstract: A tungsten carbide ceramic material which cuts titanium alloys four to five times faster than cemented carbide, ceramic-coated cemented carbides, or state-of-the-art ceramic cutting tools can be densified with or without applied pressure at temperatures below 1700.degree. C. Grain growth inhibitors or sintering aids can be added to control grain size in the final product. The polycrystalline tungsten carbode ceramic can be formed into wear components having improved performance in comparison to cemented tungsten carbides in a variety of drilling, cutting, milling, and other wear applications.

Abstract: Liquid phase sintering is used to densify silicon carbide based ceramics using a compound comprising a rare earth oxide and aluminum oxide to form liquids at temperatures in excess of 1600.degree. C. The resulting sintered ceramic body has a density greater than 95% of its theoretical density and hardness in excess of 23 GPa. Boron and carbon are not needed to promote densification and silicon carbide powder with an average particle size of greater than one micron can be densified via the liquid phase process. The sintered ceramic bodies made by the present invention are fine grained and have secondary phases resulting from the liquid phase.

Abstract: A leak detector employing an ion-conducting membrane is disclosed. A labelled-gas ion conducting membrane which employs a high vacuum on one side is used to detect very small quantities of said labelled-gas flowing through a minute fissure in a part or device to be tested for leaks. The labelled-gas ion conducting membrane is biased with direct current voltage to drive the labelled-gas ions through the membrane away from the high vacuum side.

Abstract: An electrochemical oxygen generating device employing oxygen-conducting metal oxide electrolyte and a silver or silver alloy containing non-porous electrode is disclosed.

Abstract: Ceramic bodies having a balanced overall stress pattern in which are present individual stress zones of compressive and tensile stresses and the techniques for forming said bodies are disclosed. The bodies are formed by having slightly different compositional patterns from one zone to another whereby during cooling there is a differential volumetric expansion or contraction in one zone as compared to an adjacent zone. The volumetric expansion or contraction is caused by a material which undergoes a phase transformation during the cooling from the sintering temperatures utilized to sinter the ceramic body, whereby such phase transformation is accompanied by a volumetric change.

Abstract: A leak detector employing an ion-conducting membrane is disclosed. An oxygen-ion conducting membrane which employs a high vacuum on one side is used to detect very small quantities of oxygen flowing through a minute fissure in a part to be tested for leaks. The oxygen-ion conducting membrane is biased with direct current voltage to drive oxygen-ions through the membrane away from the high vacuum side.