摘要:
An improved electrochemical cell comprising an additive-modified molten alkali metal electrode-reactant and/or electrolyte is disclosed. Various electrochemical cells employing a molten alkali metal, e.g., sodium, electrode in contact with a cationically conductive ceramic membrane experience a lower resistance and a lower temperature coefficient of resistance whenever small amounts of selenium are present at the interface of the electrolyte and the molten alkali metal. Further, cells having small amounts of selenium present at the electrolyte-molten metal interface exhibit less degradation of the electrolyte under long term cycling conditions.
摘要:
An energy conversion device comprising an improved sealing member adapted to seal a cation-permeable casing to the remainder of the device. The sealing member comprises a metal substrate which (i) bears a nonconductive and corrosion resistant coating on the major surface to which said casing is sealed, and (ii) is corrugated so as to render it flexible, thereby allowing said member to move relative to said casing without cracking the seal therebetween. Corrugations may be circumferential, radial, or both radial and circumferential so as to form dimples. The corrugated member may be in form of a bellows or in a substantially flat form, such as a disc.
摘要:
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.
摘要:
The present invention concerns improved configurations for a fuel cell army. The contacts for the positive electrode and the negative electrode are made outside the higher temperature active reaction space in a cooler area. Thus different more common materials are used which have a longer lifetime and have less stresses at their lower operating temperature. The invention utilizes tubular cell components connected with spines for efficient electron transfer and at least two manifolds outside the reaction zone, which may be cooled by external means. The external protruding connectors are thus at a lower operating temperature. This invention improves fuel cell life span, provides for lower cost, use of more common materials, and reduces the number thermal defects during operation.
摘要:
A solid oxide fuel cell stack having a plurality of integral component fuel cell units, each integral component fuel cell unit having a porous anode layer, a porous cathode layer, and a dense electrolyte layer disposed between the porous anode layer and the porous cathode layer. The porous anode layer forms a plurality of substantially parallel fuel gas channels on its surface facing away from the dense electrolyte layer and extending from one side to the opposite side of the anode layer, and the porous cathode layer forms a plurality of substantially parallel oxidant gas channels on its surface facing away from the dense electrolyte layer and extending from one side to the opposite side of the cathode. A flexible metallic foil interconnect is provided between the porous anode and porous cathode of adjacent integral component fuel cell units.
摘要:
Enhancement of mechanical properties of ceramic membranes by introduction of a uniformly distributed high-temperature oxidation-resistant metal phase into the brittle ceramic phase to achieve mechanically strong ceramic/metal composites operable in an oxidation atmosphere and at elevated temperatures.
摘要:
An improved electrode design for solid state devices, fuel cells, sensors and the like is made by incorporation of a porous layer of the electrolyte material over the dense electrolyte, and by the introduction of an electrocatalyst into the porous layer such that it is also continuous. The resulting electrode structure of dense electrolyte/porous electrolyte, continuous electrocatalyst and gas phase are present creating an enhanced three phase (TPB) length over that of conventional designs. The design allows for improved performance at lower temperatures which means a lower cost of materials, fewer problems from oxidation and corrosion, and improved durability. In a preferred embodiment, the dense electrolyte and porous electrolyte is yttria-stabilized zirconia (YSZ), and the electrocatalyst is selected from silver; platinum; rhodium; palladium; iridium; ruthenium;(La.sub.1-x Sr.sub.x) MnO.sub.3, wherein x is 0 to 0.5;(La.sub.1-x Sr.sub.x) CoO.sub.3, wherein x is 0 to 0.6;(La.sub.1-x Sr.sub.x)(Co.sub.1-y Fe.sub.y)O.sub.3, wherein x is 0 to 0.4 and y is 0 to 0.8;In.sub.2 O.sub.3 --PrO.sub.1.83 --ZrO.sub.2, having composition ratios of In.sub.2 O.sub.3 of 0-90%, PrO.sub.1.83 of 10-60% and ZrO.sub.2 of 0 to 50%;TbO.sub.2 being 35 to 40% doped with YSZ;SnO.sub.2 being 0 to 20% doped with In.sub.2 O.sub.3 ;ZrO.sub.2 being 0 to 40% doped with In.sub.2 O.sub.3 ;Sm.sub.0.5 Sr.sub.0.5 CoO.sub.3 ;La.sub.0.6 Ca0.4MnO.sub.3 ;Y.sub.1-x Ca.sub.x FeO.sub.3, wherein x is 0 to 1;SrCo.sub.1-x Fe.sub.x O.sub.3, wherein x is 0.2 to 0.8;TiO.sub.2 being 0-30% doped with YSZ; or mixtures thereof.
摘要:
Disclosed is a stable bismuth oxide composition having excellent oxygen ion conductivity comprising: from 50 to 90 mole % Bi.sub.2 O.sub.3, from 10 to 40 mole % of a rare earth oxide, such as yttria; and from 0.1 to 10 mole % g an oxide compound, such as ZrO.sub.2 or ThO.sub.2. The composition retains its oxygen ion transport capabilities even after prolonged annealing.
摘要翻译:公开了具有优异的氧离子传导率的稳定的氧化铋组合物,其包含:50至90摩尔%的Bi 2 O 3,10至40摩尔%的稀土氧化物,例如氧化钇; 和0.1至10摩尔%的氧化物化合物,例如ZrO 2或ThO 2。 即使在长时间退火后,组合物仍保留其氧离子传输能力。
摘要:
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.
摘要:
A method of separating oxygen from an oxygen containing gas with a composite membrane capable of conducting oxygen ions and electrons. In accordance with the method, the composite membrane is subjected to an operational temperature and the oxygen containing gas at a cathode side thereof. The composite membrane has a dense layer, at least one active porous layer contiguous to the dense layer, and at least one porous support layer. The active porous layer has a thickness and a distribution of pore radii. The distribution of pore radii has a standard deviation from a theoretical radius that would produce a maximum operation flux through the thickness when the thickness is about equal to a product of a constant and the square root of the theoretical radius. The constant is a function of a material used to fabricate the active porous layer, the operational temperature and an oxygen partial pressure within the active porous layer, and a porosity and a tortuosity produced by the pore radii. The standard deviation of the log of the theoretical radius is equal to a product of 1.45 and a shape factor, the shape factor being greater than 0 and no greater than about 0.5.