Abstract: The invention relates to a method of preparing beta alkaline alumina parts particularly for use as solid electrolytes in electric cells of the sodium-sulphur type. It consists in mixing alumina and an alkaline carbonate in predetermined quantities, heating the mixture, crushing after cooling, forming the parts, sintering them and, after said forming, but prior to sintering depositing a layer of a compound of said alkaline metal on the surface of the parts in contact with the atmosphere to create an atmosphere rich in sodium in the immediate vicinity of the parts during sintering for compensating any loss of the element which may occur from the parts and minimizing the loss of alkaline metal by diffusion towards the outside of the parts.

Abstract: Method for manufacturing alkaline beta alumina parts, consisting in heating a mixture of alumina and of sodium carbonate, in crushing the powder obtained, in shaping the parts, in sintering them at 1650.degree. C, those parts being arranged in a sintering enclosure suitable for creating, in the vicinity of the parts, an atmosphere which is rich in sodium. The invention is implemented in the embodiment of an electrolyte for sodium-sulphur cells.

Abstract: The alpha alumina part is heated to between 1400.degree. C and 1600.degree. C for 10 to 20 hours in a mass of alkaline carbonate or aluminate. It is then disposed in contact with a blank of the alkaline beta alumina part in a sintering enclosure suitable for establishing an atmosphere which is rich in alkaline metal and in heating this enclosure to between 1600.degree. C and 1700.degree. C for between 30 minutes and 4 hours, so as to sinter the alkaline beta alumina part while effecting the connection thereof to the alpha alumina part. The invention is used in manufacturing sodium-sulphur type electric cells.

Abstract: The invention relates to a new structure for a sodium-sulphur cell. Such a cell comprises a cathode tank containing sulphur, an electrolyte tube closed, at its lower end, containing sodium and immersed in sulphur, a sodium anode tank, a ceramic support holding the said tank and the tube, the cathode tank being fitted with graphite felt washers ensuring cathode collection of the current, the outside face of the electrolyte tube being, except for the lower end, lined with a porous insulating coating, a graphite felt part being, moreover, inserted between the said lower end of the electrolyte tube and the bottom of the cathode tank. The invention is implemented in sodium sulphur cell batteries for electric vehicles.

Abstract: The invention relates to a sodium-sulphur battery for electrical drive. It is formed by elements each comprising a cathode tank containing sulphur, a solid electrolyte tube closed at its lower end, containing sodium and arranged in the said cathode tank, a ceramic insulating support for keeping the said electrolyte tube in the said cathode tank, an anode tank containing a supply of sodium, that battery being characterized in that it comprises m groups of n modules each comprising p elements, those elements being electrically interconnected in parallel in each of the modules by means of plates connected to the bottoms of the said cathode tanks and anode tanks respectively, each of the said plates comprising a substantially central bore. The invention is implemented for propelling all electric vehicles.

Abstract: The invention relates to a sodium-sulphur type electric cell. The cell includes a cathode tank containing sulphur and an anode tank containing sodium, fixed to an alumina plate, as well as an electrolyte tube immersed in the sulphur, such fixing being effected by disposing an aluminium seal between the tank and the plate and compressing at a temperature close to but less than the melting point of aluminium, at least the cathode tank being advantageously made of chrome-plated steel. The invention is implemented in electric cells for electric propulsion.