Abstract: An electrical battery comprises in a metallic casing filled with electrolyte at least one electrode pair comprising a separator, a positive electrode, a separator and a negative electrode, the electrodes of the same polarity being connected in parallel and to positive and negative output terminals insulated from the casing. It includes an additional electrode in contact with the bottom of the casing and impregnated with electrolyte containing an electrochemically active material chosen so that its electrochemical potential is in the range of passivating and stabilizing the metal of the casing. In one embodiment the casing is made of aluminum and the additional electrode is made from a material selected from a metallic oxide or sulfide, containing lithium or not, the potential of which relative to lithium is in the range 2 V to 3.5 V, for example V.sub.2 O.sub.5, Li.sub.x V.sub.2 O.sub.5, MnO.sub.2, Li.sub.x MnO.sub.2, MoS.sub.2, Li.sub.x MOS.sub.2.

Abstract: The present invention provides a sealed electrochemical cell comprising a container containing a spiral-wound electrochemical group and at least one safety device for the event of a rise in internal pressure, wherein said safety device comprises gas vent first means allowing gas to escape to the outside of said container in the event of internal pressure rising, co-operating with holding second means for holding said group inside said container and organized so as to create a gap between said group and the inner wall of said container to allow said gas to flow.

Abstract: A separator for an electrochemical generator is constituted by a microporous polyolefin film grafted with at least one monomer selected from diethyleneglycol dimethacrylate, furfuryl acrylate and a diethyleneglycol dimethacrylate/acrylic acid mixture. In a process for the production of a separator of this kind grafting of the monomer is carried out in three stages:irradiation of the film,if required, storage of the irradiated film,immersion of the irradiated film in the grafting solution comprising the monomer, a solvent, and at least one additive. The separator may be used in an electrochemical generator with either an aqueous or nonaqueous electrolyte where the salt concentration is between 1M and 2M.

Abstract: A process of making a cathode material for a secondary battery including a lithium anode and application of said material.A process of making a cathode material for a secondary electrochemical battery including a lithium anode, wherein said material corresponds to one of the formulas Li.sub.y Ni.sub.2-y O.sub.2 or LiNi.sub.1-x Co.sub.x O.sub.2, wherein y is a number ranging from 0.84 to 1.22 and x is a number ranging from 0.09 to 0.5, wherein the base is lithium hydroxide, nickel oxide or possibly cobalt oxide, in a powdered form in the desired stoichiometric ratio, and wherein it is heated in air at a temperature ranging from approximately 600.degree. C. to 800.degree. C.

Abstract: A rechargeable electrochemical battery including a lithium anode.A rechargeable electrochemical battery wherein the anode 2 is a lithium base and the electrolyte is composed of a solution of a lithium salt in a non-aqueous solvent. The active material of cathode 1 is a manganese dioxide containing lithium ions and displaying the crystallographic structure of .alpha. manganese dioxide known as cryptomelane.

Abstract: A cell operable at temperatures between 100.degree. C. and 200.degree. C. includes a non-aqueous electrolyte which comprises at least one solvent belonging to the class of aromatic or aliphatic linear sulfones. The negative active material of the cell may be lithium, for example, and its positive active material is selected from the group constituted by oxides, oxisalts, and sulfides. The electrolyte includes as a solvent, in particular, dimethylsulfone alone or mixed with other aromatic or aliphatic linear sulfones.

Abstract: Positive active material (2) for electrochemical cells, characterized by the fact that it is constituted by an anhydrous borate having the formula Bi.sub.4 B.sub.2 O.sub.9. The invention is applicable to cells using lithium as the negative active material and the electrolyte may be solid or liquid.

Abstract: A lithium - manganese dioxide cell in which a certain quantity of copper oxyphosphate is added to the manganese dioxide to obtain a second discharge voltage plateau for use in detecting the end of cell life before it is too late.

Abstract: A positive active material for an electric cell, said material being constituted by anhydrous copper borate whose formula is Cu.sub.3 B.sub.2 O.sub.6. A method of making such an active material. An electric cell whose positive active material (3) is anhydrous copper borate Cu.sub.3 B.sub.2 O.sub.6, whose negative active material (6) is lithium and whose electrolyte is a solution which is liquid at ambient temperature and whose solvent is an aprotic compound.

Abstract: A battery having a lithium anode, an electrolyte solution in which the solvent is an aprotic composition, and cathode in which the positive active material is formed from particles of a lead oxide having the formula PbO.sub.x, where x has values from 1.5 to 1.87. The PbO.sub.x positive active material produces a battery with a high specific energy and a single discharge level.

Abstract: The invention relates to a positive active material for an electric cell. Such an active material is constituted by a vitreous compound which results from the addition of a small quantity of silica to at least one electrochemically reducible metal oxide. Application to electric cells with non-aqueous electrolyte, the negative electrodes of these cells being based on an alkali or alkali-earth metal.

Abstract: The invention relates to a solid positive active material for electric cells whose negative active material is an alkali metal. In accordance with the invention, said positive material is a compound formed by two oxides, namely, bismuth oxide Bi.sub.2 O.sub.3 and cupric oxide CuO. Application to lithium cells.

Abstract: A high specific energy electric cell having a lithium negative active material, an electrolyte solution of which the solvent is an aprotic liquid, and the positive active material is a derivative of divalent lead oxide, PbO. The lead oxide derivation is a compound of said PbO and an oxide selected from the group comprising the oxides of bismuth, Bi.sub.2 O.sub.3, antimony, Sb.sub.2 O.sub.3, and tin, SnO.sub.2.

Abstract: Electrolytes for use in lithium primary cells are made from a mixture of three organic solvents and an alkaline solute. The first solvent is chosen to have a dielectric constant greater than 35 (e.g. propylene carbonate), the second solvent is a linear polyether with its ether functional groups in the .gamma. position (e.g. 1-2 dimethoxyethane) and the third solvent has a high solvation power for dissolving large quantities of the alkaline salt (e.g. 1-3 dioxolane). The solvents are so chosen that the conductivity maxima of the electrolytes that would be obtained by mixing the solvents in pairs are higher than the conductivity maxima of the electrolytes that would be obtained by using each of the solvents on its own. The positive electrode cell using the electrolyte may be cupric oxide or ferrous disulphide.