The invention relates to ionic compositions having a high ionic conductivity comprising a salt with a delocalized anionic charge. An ionic composition comprises a salt in solution in a solvent and has a conductivity of greater than 10−5 S.cm−1 between −30° C. and 150° C. The cation is a proton, a hydronium, a hydroxonium, a nitrosonium NO+, an ammonium NH4+ or a metal, organic or organometallic cation. The anion is a carbanion carrying a perfluorinated substituent or a substituent carrying at least one F on the carbon &agr; to the carbanion and two nonperfluorinated electron-withdrawing substituents. Use as electrolyte in electrochemical devices, as catalyst of chemical reactions, or as photochemical or thermochemical initiator for polymerization or crosslinking reactions.