(DE19619233-A1)      Fluorine-containing solvent for lithium batteries is claimed. The solvent is a partially fluorinated ether of formula: RO((CH2)mO)nCF2CFHX (I) or XCFCHCF2O((CH2)mO)nCF2CFHX (II) (where R = 1-10C linear alkyl, or 3-10C branched alkyl; X = F, Cl or 1-6C perfluoroalkyl also containing ether oxygen; m = 2-6; and n = 1-8), and is added to the electrolyte system of the battery.    USE -   Used in rechargeable batteries for high quality camcorders, laptops, etc.    ADVANTAGE -   The solvent increases the safety of the battery and has high thermal stability, high flash point, low vapour pressure, low viscosity, can be mixed with usual battery solvents, and has high stability towards metallic lithium.    (JP10050343-A)      Fluorine-containing solvent for lithium batteries is claimed. The solvent is a partially fluorinated ether of formula: RO((CH2)mO)nCF2CFHX (I) or XCFCHCF2O((CH2)mO)nCF2CFHX (II) (where R = 1-10C linear alkyl, or 3-10C branched alkyl; X = F, Cl or 1-6C perfluoroalkyl also containing ether oxygen; m = 2-6; and n = 1-8), and is added to the electrolyte system of the battery.    USE -   Used in rechargeable batteries for high quality camcorders, laptops, etc.    ADVANTAGE -   The solvent increases the safety of the battery and has high thermal stability, high flash point, low vapour pressure, low viscosity, can be mixed with usual battery solvents, and has high stability towards metallic lithium.    (US5916708-A)      Fluorine-containing solvent for lithium batteries is claimed. The solvent is a partially fluorinated ether of formula: RO((CH2)mO)nCF2CFHX (I) or XCFCHCF2O((CH2)mO)nCF2CFHX (II) (where R = 1-10C linear alkyl, or 3-10C branched alkyl; X = F, Cl or 1-6C perfluoroalkyl also containing ether oxygen; m = 2-6; and n = 1-8), and is added to the electrolyte system of the battery.    USE -   Used in rechargeable batteries for high quality camcorders, laptops, etc.    ADVANTAGE -   The solvent increases the safety of the battery and has high thermal stability, high flash point, low vapour pressure, low viscosity, can be mixed with usual battery solvents, and has high stability towards metallic lithium.