The subject of the invention at hand are novel, a little basic, fluorinated pentafluorophenyl imide anions, which can be used as anions in ionic liquids. Methods for producing ionic liquids are described, which contain these novel pentafluorophenyl imide ions as anions, as well as quaternary organic ammonium ions, guanidinium ions, N-organo-pyridinium ions, imidazolium, imidazolidinium or benzimidazolidinium ions, alkyl-alkylidene phosphoranes or aryl-alkylidene phosphoranes as cations. Alternative methods according to the present invention provide ionic liquids through reaction of ketene N,N-diacetals or alkyl or aryl-alkylidene phosphoranes with acids.The ionic liquids according to the present invention are suitable, for example, as solvents for syntheses, as mobile and/or stationary phase in chromatography, as electrolyte systems for batteries, galvanic elements, fuel cells and rechargeable battery packs.