Abstract: In an electric cell having a solid electrolyte which bounds on one side a mpartment for liquid anode and on its opposite side a compartment for liquid cathode, the liquid anode compartment is made of very limited capacity. The bulk of the liquid anode required by the cell is held in a reservoir and fed to the liquid anode compartment by a capillary duct to provide a restricted feed which limits the flow of liquid anode therebetween. The reservoir may be disposed within the cell, or outside the cell, and may supply liquid anode to several cells.

Abstract: The invention comprises an electric battery of the kind for use with a liquid anode, a liquid cathode and a solid electrolyte, and having a number of cells nested one within the other such that adjacent cells share and are separated by a common electrode.The common electrode may provide a series connection or a parallel connection between adjacent cells.

Abstract: A sodium-sulphur cell is provided having a ceramic spacer means disposed in he liquid sulphur compartment to provide a region substantially free from cathodic reactions. The spacer means is disposed adjacent to materials likely to be adversely affected by said cathodic reactions, such as glass seals used to join the solid electrolyte to a ceramic support member, or a metallic end cap provided to close the liquid sulphur compartment.

Abstract: In an electric cell having a solid electrolyte and employing sodium as the iquid anode and sulphur as the liquid cathode, the liquid anode is contained in two compartments separated by a corrosion resistant barrier. Liquid anode is arranged to flow between the compartments through a flow restrictor which permits a rate of flow sufficient to meet the normal charge and discharge requirements of the cell but limits higher rates of flow.One of the compartments has a very limited capacity for liquid sodium and is disposed about one side of the solid electrolyte to define a wicking space to constrain liquid sodium to flow over the solid electrolyte. The other compartment provides a reservoir for containing the bulk of the liquid sodium.In the event of damage to the solid electrolyte, only a very limited amount of liquid sodium is readily available to mix and react with the liquid sulphur.

Abstract: A sodium-sulphur electric cell is provided having a sulphur compartment in hich a current collector of hollow form extends. The space inside the current collector is used as an expansion space for products arising from reaction of sodium and sulphur. The walls of the current collector may be tapered to arrange that the current density along it is substantially constant.

Abstract: In a sodium-sulphur battery cell, an extended surface area current collector is sandwiched between portions of solid electrolyte, also of extended surface area, which provide between them a space for the liquid sulphur. The spacing between the current collector and each of the portions does not exceed the maximum distance that the sodium ions can diffuse in the liquid sulphur during a specified recharge time. A plurality of portions defining a plurality of spaces for the liquid sulphur may be provided, each space having an extended surface area current collector sandwiched between the portions defining the space.A plurality of these battery cells may be arranged so that they are separated one from another by a bipolar electrode to provide a series connection.