Electrolyte systems for lithium batteries with enhanced safety containing at least one lithium-containing conductive salt and at least one electrolyte liquid, in which the electrolyte liquid includes an effective amount of at least one partially fluorinated amide of formula (I) R1CO—NR2R3  (I) in which R1 is a linear C1-C6 alkyl group, or a branched C3-C6 alkyl group, in which one or more hydrogen atoms are replaced by fluorine atoms; or a C3-C7 cycloalkyl group optionally substituted one or more times by a linear C1-C6 alkyl group and/or branched C3-C6 alkyl group, in which one or more hydrogen atoms of are replaced by fluorine atoms; and R2 and R3 independently represent an identical or different linear C1-C6 alkyl group, a branched C3-C6 alkyl group or a C3-C7 cycloalkyl group, or R2 and R3 together with the amide nitrogen form a saturated five or six-member nitrogen-containing ring.