TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: Conducting salt is selected from Li(F6-xP(CyF2y+1)), Li(B(R2)4), Li(B(R2)2(OR3O)) and Li(B(OR3O)2), salts of Li(X(CnF2n+1SO2)m), LiCIO4, LiAsF6, LiCF3SO3, Li2SiF6, LiSbF6, LiAICI4, lithium tetrafluoro (oxalato) phosphate and lithium oxalate. Cathode active material contains material capable of occluding and releasing lithium ions chosen from lithiated transition metal phosphates of olivine structure, lithium ion intercalating transition metal oxides with layer structure and lithiated transition metal mixed oxides of spinel structure. Cathode active material is chosen from LiCoPO4, transition metal oxides with layer structure of formula Li(1+z)(NiaCobMnc)(1-z)O2+e, and lithiated transition metal mixed oxides of spinel structure of formula Li1+fM2-tO4-d. Anode active material contains material capable of occluding and releasing lithium ion selected from carbonaceous material, oxides of titanium, silicon, lithium, lithium alloys and materials capable of forming lithium alloys.x=0-6;y=1-20;R2=F, Cl, Br, I, 1-4C alkyl, 2-4C alkenyl, and 2-4C alkinyl which may be substituted by greater than or equal to 1 OR4;R4=1-6C alkyl, 2-6C alkenyl and 2-6C alkinyl;OR3O=bivalent group derived from 1,2- or 1,3-diol, 1,2- or 1,3-dicarboxlic acid or 1,2- or 1,3-hydroxycarboxylic acid and forms a 5- or 6-membered cycle via both O with central B-atom;m=1 when X is O and S, 2 when X is N and P and 3 when X is C and Si;n=1-20;z=0-0.3;a,b,c=0-0.8;a+b+c=1;e=- 0.1-0.1;d=0-0.4;t=0-0.4; andM=Mn or group 3-12 metal.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: Ester compound (I) is chosen from di-(1,1,1,3,3,3-hexafluoro-2-propyl)oxalate, (1,1,1,3,3,3- hexafluoro-2-propyl)acetate, and propionic acid (1,1,1,3,3,3-hexafluoroisopropyl)ester. Aprotic organic solvent is selected from cyclic and noncyclic organic carbonates, which may be partly halogenated, di-1-10 carbon containing alkylethers which may be partly halogenated, di-1-4 carbon containing alkyl-2-6 carbon containing alkylene ethers and polyethers, which may be partly halogenated, cyclic ethers, which may be partly halogenated, cyclic and acyclic acetales and ketales, which may be partly halogenated, orthocarboxylic acids esters, which may be partly halogenated, cyclic and noncyclic esters of carboxylic acids, which may be partly halogenated, cyclic and noncyclic sulfones, which may be partly halogenated, cyclic and noncyclic nitriles and dinitriles, which may be partly halogenated, and ionic liquids, which may be partly halogenated. Additive is chosen from vinylene carbonate and its derivatives, vinyl ethylene carbonate and its derivatives, methyl ethylene carbonate and its derivatives, lithium (bisoxalato) borate, lithium difluoro (oxalato) borate, lithium tetrafluoro (oxalato) phosphate, lithium oxalate, 2-vinyl pyridine, 4-vinyl pyridine, cyclic exo-methylene carbonates, sultones, organic esters of inorganic acids, acyclic and cyclic alkanes having boiling point at 1 bar of greater than or equal to 36 degrees C, and aromatic compounds, optionally halogenated cyclic and acyclic sulfonylimides, optionally halogenated cyclic and acyclic phosphate esters, optionally halogenated cyclic and acyclic phosphines, optionally halogenated cyclic and acyclic phosphites, optionally halogenated cyclic and acyclic phosphazenes, optionally halogenated cyclic and acyclic silylamines, optionally halogenated cyclic and acyclic halogenated esters, optionally halogenated cyclic and acyclic amides, optionally halogenated cyclic and acyclic anhydrides, and optionally halogenated organic heterocycles. Amount of compound (I) is 0.001-60 wt.%, preferably 1-15 wt.%. Electrolyte composition contains 39.9-99.9 wt.% aprotic organic solvent, 0.1-25 wt.% conducting salt, 0.001-60 wt.% compound (I), and 0-10 wt.% additive. Preferred Definitions:    A1-A6=F;    R=C(O)OR1; and    R1=2-propyl which is substituted by 1-6 F.