Abstract: In a sodium-sulphur cell having a solid electrolyte separating sodium from a cathodic region containing sulphur/polysulphides in a graphite felt, a cathode current collector is formed of an aluminium substrate on which is an interstrate layer of nickel-chromium alloy covered by a coating of titanium oxide or other electronically conductive oxide intrinsically inert to the cathodic reactant.

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: In a sodium-sulphur electric cell, a circuit breaking device responsive to temperature or current is inserted inside the cell in series in the internal electric circuit of the cell so as to open circuit the cell in the event of either an abnormal cell temperature or current. The circuit breaking device may be in the form of a fusible metal link or a temperature sensitive switch.

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.