TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The compound (I) is preferably of formula (II). The aprotic organic solvent is optionally partially halogenated cyclic or noncyclic organic carbonates, optionally partially halogenated di-1-10C alkylether, optionally partially halogenated di-1-4C-alkyl-1-6C-alkylene ether and polyether, optionally partially halogenated cyclic ether, partially halogenated cyclic and acyclic acetal and ketal, optionally partially halogenated orthocarboxylic acids ester, optionally partially halogenated cyclic and noncyclic ester of carboxylic acid, optionally partially halogenated cyclic and noncyclic sulfone, optionally partially halogenated cyclic and noncyclic nitrile and dinitrile, and/or optionally partially halogenated ionic liquid. The additive is chosen from vinylene carbonate or its derivative, vinyl ethylene carbonate or its derivative, methyl ethylene carbonate or its derivative, lithium(bisoxalato)borate, lithium difluoro(oxalato)borate, lithium tetrafluoro(oxalato)phosphate, lithium oxalate, 2-vinyl pyridine, 4-vinyl pyridine, cyclic exo-methylene carbonate, sultone, organic ester of inorganic acid, acyclic and cyclic alkane having boiling point at 1 bar of 36 degrees C or more, and aromatic compound, optionally halogenated cyclic and acyclic sulfonylimide, optionally halogenated cyclic and acyclic phosphate ester, optionally halogenated cyclic and acyclic phosphine, optionally halogenated cyclic and acyclic phosphite, optionally halogenated cyclic and acyclic phosphazene, optionally halogenated cyclic and acyclic silylamine, optionally halogenated cyclic and acyclic halogenated ester, optionally halogenated cyclic and acyclic amide, optionally halogenated cyclic and acyclic anhydride, ionic liquid and optionally halogenated organic heterocyclic compounds. The concentration of compound (I) with respect to total weight of electrolyte composition is 0.001-10 wt.%. The conducting salt contains lithium hexafluorophosphate of formula: Li(F6-xP(CyF2y+1)x), lithium borate of formula: Li(B(R9)4), lithium borate of formula: Li(B(R9)2(OR10O)), lithium borate of formula: Li(B(OR10O)2), lithium fluorocarbon of formula: Li(X(CnF2n+1SO2)m), lithium perchlorate, lithium hexafluoroarsenate(V), lithium trifluoromethanesulfonate, lithium hexafluorosilicate dihydrate, lithium hexafluoroantimonate, lithium tetrachloroaluminate, lithium bis(fluorosulfonyl)imide, lithium tetrafluoro(oxalato)phosphate and/or lithium oxalate.R1a=-C(=O)-, -C(=O)O-, -C(=O)C(=O)O-, C(=O)R7aC(=O)O-, -S(O)2-, -S(O)2O-, -(CH2)sSO2(CH2)tO-, -P(O)(OR7b), or -P(O)(OR7b)O-;R2-R6,R2a-R6a=1-6C alkyl, 3-6C (hetero)cycloalkyl, 2-6C alkenyl, 3-6C (hetero)cycloalkenyl, 2-6C alkynyl, 5-7C (hetero)aryl or 6-13C aralkyl (all optionally substituted by fluoro, CN or optionally fluorinated oxiranyl), H or fluoro;R7a=1-4C alkanediyl, 2-4C alkenediyl, 2-4C alkynediyl or 1,2-oxiranediyl;R7b=1-6C alkyl, 3-6C (hetero)cycloalkyl, 2-6C alkenyl, 3-6C (hetero)cycloalkenyl, 2-6C alkynyl, 5-7C (hetero)aryl or 6-13C aralkyl (all optionally substituted by F, CN or optionally fluorinated oxiranyl);x=0-6;y=1-20;R9=1-4C alkyl, 2-4C alkenyl or 2-4C alkynyl (all optionally substituted by OR11), fluoro, chloro, bromo or iodo;R11=1-6C alkyl, 2-6C alkenyl or 2-6C alkynyl;X=O, S, N, P or C;OR10O=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, in which bivalent group optionally combines with central B-atom through both oxygen atoms to form 5- or 6-35 membered ring;m=1-3;andn=1-20.(i) m is 1, when X is O or S; (ii) m is 2, when X is N or P; and (iii) m is 3, when X is C or S.