Abstract: A fuel cell assembly comprises at least one fuel cell. The fuel cell comprises an anode and a cathode held in a spaced apart relationship by at least one spacer element comprising an electrically insulating material. A proximal end of the spacer element is in contact with the cathode, and a distal end is in contact with the anode. An electrolyte is disposed between, and in contact with the anode and the cathode. The electrolyte comprises a molten salt having a hydride ion conductance number greater than about 0.95 at a fuel cell operating temperature. A fuel gas inlet, adjacent to the cathode, is provided for delivering a fuel gas to the electrolyte. An oxidizing gas inlet, adjacent to the anode, is provided for delivering an oxidizing gas to the electrolyte. An exhaust port is in fluid communication with the anode.

Abstract: A fuel cell assembly comprises at least one fuel cell. The fuel cell comprises an anode and a cathode held in a spaced apart relationship by at least one spacer element comprising an electrically insulating material. A proximal end of the spacer element is in contact with the cathode, and a distal end is in contact with the anode. An electrolyte is disposed between, and in contact with the anode and the cathode. The electrolyte comprises a molten salt having a hydride ion conductance number greater than about 0.95 at a fuel cell operating temperature. A fuel gas inlet, adjacent to the cathode, is provided for delivering a fuel gas to the electrolyte. An oxidizing gas inlet, adjacent to the anode, is provided for delivering an oxidizing gas to the electrolyte. An exhaust port is in fluid communication with the anode.

Abstract: An electrochemical corrosion potential sensor includes a ceramic tip insulating member, and a sensor tip joined to the ceramic tip insulating member, the sensor tip comprising an alloy. Further, a coating is provided on an outer surface of the sensor tip, the coating including a noble metal, and a conductor electrically connected to said sensor tip.

Abstract: A method for fabricating an electrode having extended operating life comprising brazing a cap and adapter to an insulator composed of magnesium oxide-stabilized zirconia (MSZ), calcium oxide stabilized zirconia (CSZ) or yttroim oxide-stabilized (YSZ). Electrodes comprising insulators composed of CSZ, MSZ and/or YSZ are also described.

Abstract: A system for converting heat energy into electricity includes a conversion cell comprising a pair of spaced-apart electrodes having an electrolyte therebetween. The electrolyte is selected to pass negatively-charged hydrogen ions and to inhibit the passage of atomic hydrogen and positive hydrogen ions. Inducing a flow of hydrogen through the cell, a current may be generated between the electrodes as electrons are gained by the hydrogen as it enters the cell and lost by the hydrogen as it leaves the cell. In the preferred embodiment, hydrogen flow is induced by reacting the hydrogen leaving the cell with a mixture of lithium and sodium to form the metal hydride. The metal hydride is then thermally decomposed to release the hydrogen and the molten metal to be recycled to the cell. In this way, the thermal energy used to decompose the metal hydride is converted into electrical energy by passing the hydrogen through the conversion cell.

Abstract: A secondary electrochemical cell includes a source of hydrogen as the hydrogen-providing reactant and an alkali or alkaline earth metal as the metal reactant. Hydrogen may be from H.sub.2 gas or a metal hydride. By separating the two reactants by a barrier selective for the passage of hydrogen ions, current flow may be induced in an external circuit connected across the barrier. The barrier is typically an electrolytic salt enclosed between a pair of solid metal electrodes. Electrons are gained by the hydrogen as it enters the electrolyte and lost by the hydrogen as it leaves the electrolyte. By connecting the metal electrodes, a circuit is established.

Abstract: A system for converting heat energy into electricity includes a conversion cell comprising a pair of spaced-apart electrodes having an electrolyte therebetween. The electrolyte is selected to pass negatively-charged hydrogen ions and to inhibit the passage of atomic hydrogen and positive hydrogen ions. Inducing a flow of hydrogen through the cell, a current may be generated between the electrodes as electrons are gained by the hydrogen as it enters the cell and lost by the hydrogen as it leaves the cell. In the preferred embodiment, hydrogen flow is induced by reacting the hydrogen leaving the cell with lithium or sodium to form the metal hydride. The metal hydride is then thermally decomposed to release the hydrogen and the molten metal to be recycled to the cell. In this way, the thermal energy used to decompose the metal hydride is converted into electrical energy by passing the hydrogen through the conversion cell.

Abstract: A system for converting heat energy into electricity includes a conversion cell comprising a pair of spaced-apart electrodes having an electrolyte therebetween. The electrolyte is selected to pass negatively-charged hydrogen ions and to inhibit the passage of atomic hydrogen and positive hydrogen ions. Inducing a flow of hydrogen through the cell, a current may be generated between the electrodes as electrons are gained by the hydrogen as it enters the cell and lost by the hydrogen as it leaves the cell. In the preferred embodiment, hydrogen flow is induced by reacting the hydrogen leaving the cell with lithium or sodium to form the metal hydride. The metal hydride is then thermally decomposed to release the hydrogen and the molten metal to be recycled to the cell. In this way, the thermal energy used to decompose the metal hydride is converted into electrical energy by passing the hydrogen through the conversion cell.

Abstract: An electrochemical device for measuring the concentration of oxygen in liquid alkali metal is described. Such device includes an elongated probe tube which is designed to be inserted into the liquid alkali metal whose oxygen content is of interest. A cup of a solid electrolyte material is bonded to the tube adjacent its lower end so that the outside surface of its bottom wall is in intimate contact with the liquid metal. The cup contains a mixture comprising a known concentration of one of the free metals gallium, indium and tin, and an oxide of such metal. This mixture is liquid at the temperature of operation of the device and is in intimate contact with the inner side of the bottom wall of the cup to provide a reference electrode.

Abstract: A diffusion tube hydrogen meter for improving the sensitivity and response time for the measurement of hydrogen in liquid sodium. The improved hydrogen meter has a composite membrane composed of pure nickel sleeve fitted, for example, over a 2 1/4 Cr-1 Mo steel or niobium diffusion tube. Since the hydrogen permeation rate through 2 1/4 Cr-1 Mo steels is a factor of four higher than pure nickel, and the permeation rate of hydrogen through niobium is two orders of magnitude greater than the 2 1/4 Cr-1 Mo steel, this results in a decrease in response time and an increase in the sensitivity.

Abstract: A method of determining the oxygen content of a liquid metal is disclosed and comprises measuring the EMF across an electrolytic cell in which one of the electrodes comprises the liquid metal and the other electrode is a reference electrode of a mixture comprising a known concentration of one of the metals selected from the group of gallium, indium and tin, and an oxide of said metal with the mixture being liquid at the temperature of measurement, and the electrolyte is an oxygen ion conductive, solid electrolyte body wall having a pair of opposite side surfaces with the first one of said surfaces being in intimate contact with the liquid and the other one of said surfaces being in intimate contact with said reference electrode.

Abstract: An electrochemical carbon meter is described which is especially useful for measuring the concentration of carbon in liquid sodium. The meter includes a carbon activity gas having a known ratio of carbon monoxide to carbon dioxide contained within a chamber as an intermediary between a diffusion membrane in contact with the sodium and an electrochemical cell. A calcium carbonate fixing compound is also located within the chamber for maintaining the concentration of carbon dioxide therein at a predetermined level. The chamber is fixed to the end of a probe tube which supports the same fully surrounded by liquid sodium to be maintained thereby at a uniform temperature.