Abstract: A method of generating steam by heating water in a steam generator comprising a plurality of steam generating channels, wherein water is supplied at a constant rate to each steam generating channel through respective water supply lines, and wherein a sufficient pressure drop is provided across each water supply line in order to prevent flow reversal in the plurality of steam generating channels.

Abstract: A solid oxide fuel cell (SOFC) or SOFC sub-component comprising a YSZ solid oxide electrolyte layer (10), a LSCF cathode layer (14) and a mixed phase layer (18) comprising at least zirconia and ceria between the electrolyte layer and the cathode layer, with the cathode layer in direct contact with the mixed phase layer, that is with no ceria, other than in the mixed phase layer, between the cathode layer and the electrolyte layer. One method of forming the SOFC or sub-component comprises applying a layer of ceria on the electrolyte layer (10), heating the electrolyte and ceria layers to form the mixed phase layer (18), and removing excess ceria from the surface of the mixed phase layer before applying the cathode layer (14).

Abstract: A fuel cell stack comprising multiple arrays of one or more fuel cells, each comprising an electrolyte layer, an anode layer and a cathode layer; gas separator plates between adjacent fuel cells; and oxidant gas distribution passages and fuel gas distribution passages between adjacent fuel cells; and gas separators opening to the cathode layers and the anode layers, respectively, of the fuel cells. The fuel cell arrays comprise at least first stage fuel cell arrays having associated first fuel gas distribution passages to receive fuel gas from one or more fuel gas supply manifolds and second stage fuel cell arrays having associated second fuel gas distribution passages which receive fuel exhaust from the fuel cells of the first stage fuel cell arrays. The second stage fuel cell arrays are interleaved in the stack between first stage fuel cell arrays to improve thermal gradients. Other interleaving arrangements are possible.

Abstract: A brazing process for joining at least two components having ceramic oxide surfaces is described. The brazing filler used in the process comprises a noble metal and a second metal. During the brazing process, the filler is heated in an oxidising atmosphere such as air. The heating is undertaken until at least the noble metal is molten. The molten filler comprises a surface oxide formed from a stable, non-volatile oxide of the second metal that does not significantly alloy with the molten noble metal. The molten filler is able to wet the ceramic oxide surfaces and is subsequently cooled between them to thereby join them together.

Abstract: A method for the thermal management of a fuel cell, which method comprises: processing a fuel supply stream comprising hydrogen, steam, at least one carbon oxide and optionally methane using a methanator to produce a fuel cell supply stream comprising a controlled concentration of methane; and reforming within the fuel cell methane present in the fuel cell supply stream, wherein the way in which the methanator is operated is adjusted in response to fluctuations in the temperature of the fuel cell such that the concentration of methane in the fuel cell supply stream is controlled in order to achieve a desired level of reforming of methane within the fuel cell.

Abstract: A fuel cell stabilisation system for stabilising the supply of electrical power from a fuel cell stack (101) to a DC bus (104), including: a DC power supply (108); and a control (112) configured to enable the DC power supply (108) to supply electrical power to the DC bus (104).

Abstract: A solid oxide fuel cell (SOFC) or SOFC sub-component comprising a YSZ solid oxide electrolyte layer (10), a LSCF cathode layer (14) and a mixed phase layer (18) comprising at least zirconia and ceria between the electrolyte layer and the cathode layer, with the cathode layer in direct contact with the mixed phase layer, that is with no ceria, other than in the mixed phase layer, between the cathode layer and the electrolyte layer. One method of forming the SOFC or sub-component comprises applying a layer of ceria on the electrolyte layer (10), heating the electrolyte and ceria layers to form the mixed phase layer (18), and removing excess ceria from the surface of the mixed phase layer before applying the cathode layer (14).

Abstract: A method of operating a fuel cell (1) in which a gaseous supply stream (5) comprising a reactive species is delivered to an electrode (2) where the reactive species is consumed in an electrochemical reaction to produce an exhaust stream (7, 8) which is depleted in reactive species, which method comprises: a) assessing the concentration of reactive species in the exhaust stream (7, 8); b) relating the concentration of reactive species in the exhaust stream (7, 9) to a maximum current that may be drawn from the fuel cell (1) without redox damage of the electrode; and c) adjusting the way in which the fuel cell (1) is operated in order to optimize efficiency without redox damage of the electrode (2).

Abstract: A liquid phase reactor comprising a screw within a barrel, the screw and barrel being relatively rotatable and defining a mixing zone therebetween, the barrel having at least two inlets for introduction of components for mixing into the barrel and an outlet for discharge of a product of mixing from the barrel, the screw comprising a spiral groove whereby relative rotation of the screw and barrel is adapted to axially transport the components between the screw and barrel while mixing the components and to extrude the product through the outlet, wherein the reactor is adapted to achieve a substantially constant flow ratio of components into the barrel during operation of the reactor.

Abstract: A method of generating steam by heating water in a steam generator comprising a plurality of steam generating channels, wherein water is supplied at a constant rate to each steam generating channel through respective water supply lines, and wherein a sufficient pressure drop is provided across each water supply line in order to prevent flow reversal in the plurality of steam generating channels.

Abstract: A liquid phase continuous reactor which includes a screw rotatably disposed within a barrel and defining a mixing zone therebetween whereby the relative rotation of the screw with respect to the barrel is adapted to axially transport materials disposed between the screw and the barrel while mixing the components wherein the land surface area between the spiral groove forms at least 50% of the surface area of the screw in a mixing zone.

Abstract: A solid oxide fuel cell comprising a solid oxide electrolyte layer, a cathode layer on a cathode side of the electrolyte layer and an anode layer on an anode side of the electrolyte layer, and wherein a hydrocarbon reforming layer is also disposed on the anode side of the electrolyte layer, said hydrocarbon reforming layer having a composition different from that of the anode layer and comprising a catalyst for promoting a hydrocarbon steam reforming reaction and a component, or a precursor of such a component for alleviating carbon deposition on the hydrocarbon reforming layer.

Abstract: A method of removing sulfur from a fuel supply stream for a fuel cell (1), which method comprises: (a) hydrogenating the fuel supply stream (1) by contacting it with a hydrogenation catalyst in the presence of hydrogen to convert sulfur-containing compounds in the fuel supply stream (1) into hydrogen sulfide; (b) removing the hydrogen sulfide to produce a desulfurised fuel stream; and (c) pre-reforming the desulfurised fuel stream to produce a fuel cell feed stream, wherein a portion of the fuel cell feed stream is processed to increase its hydrogen content to produce a hydrogen-enriched fuel stream which is used in step (a) as a source of hydrogen to hydrogenate the fuel supply stream (1).

Abstract: The present invention relates to a fuel cell system and to a method of operating such a system. More specifically, the present invention relates to the manner in which a fuel delivery system of a fuel cell system is operated in order to achieve practical advantages in terms of system operation.

Abstract: A method for the thermal management of a fuel cell, which method comprises: processing a fuel supply stream in an autothermal reformer to produce a fuel cell supply stream comprising a concentration of methane; and reforming within the fuel cell methane present in the fuel cell supply stream, wherein the concentration of methane in the fuel cell supply stream is controlled by operation of the autothermal reformer in order to achieve a desired level of reforming of methane within the fuel cell.

Abstract: A method of generating hydrogen for use in a fuel cell system, which comprises processing a fuel which is essentially free of organic sulfur-containing compounds to produce a hydrogen-containing stream.

Abstract: A process for producing electricity in a fuel cell which comprises: a) pre-reforming a higher carbon (C2+) hydro-carbon fuel in a pre-reformer under conditions effective to achieve substantially complete conversion of higher carbon (C2+) hydro-carbons to produce a pre-reformed fuel stream; b) subjecting the pre-reformed fuel stream to methanation under conditions effective to produce a fuel stream having an increased concentration of methane relative to the pre-reformed fuel stream; and c) supplying the fuel stream and an oxidant to a high temperature fuel cell in which methane is reformed and electricity is produced by reacting the fuel stream at an anode of the fuel cell and reacting the oxidant at a cathode of the fuel cell.

Abstract: A fuel cell gas separator (14) between two planar solid oxide fuel cells (12) comprises a first layer (22) which is formed of a material that is impermeable to gases, a second layer (24) which is formed of a material that is impermeable to gases. The first and second layers have perforations (28) through their thickness which are closed by electrically conductive plug material (30). A third intermediate layer (26) between the first and second layers is electrically conductive and is in electrical contact with the plug material in the perforations through the first and second layers. The perforations in the first layer may be offset relative to the perforations in the second layer. The electrically conductive plug material in the perforations of the first and second layers may be the same, and may also be the same as the material of the third intermediate layer. The electrically conductive material may be silver or a silver-based material such as a silver-glass composite.

Abstract: A fuel cell gas separator member (10) comprises a layer (22) of copper or copper-based alloy having a layer (29) of oxidation-resistant material such as Al2O3 on the cathode side (30). A protective layer (31) may also be provided on the anode-side (26) of the copper or copper-based alloy layer. The copper-based alloy may be aluminium bronze in which case the oxidation-resistant layer may form automatically. Alternatively, the copper or copper-based alloy layer (22) may be wrapped in a foil (29, 31) of heat resistant steel. Other possibilities are disclosed.

Abstract: A method of operating a fuel cell (1) in which a gaseous supply stream (5) comprising a reactive species is delivered to an electrode (2) where the reactive species is consumed in an electrochemical reaction to produce an exhaust stream (7, 8) which is depleted in reactive species, which method comprises: a) assessing the concentration of reactive species in the exhaust stream (7, 8); b) relating the concentration of reactive species in the exhaust stream (7, 9) to a maximum current that may be drawn from the fuel cell (1) without redox damage of the electrode; and c) adjusting the way in which the fuel cell (1) is operated in order to optimise efficiency without redox damage of the electrode (2).