Battery has an electrolyte comprising a solvent and a salt (I) comprising a hydroxonium, nitrosonium, ammonium, metal, organic or organometallic cation and a 5-membered (hetero)cyclic anion. Battery has an electrolyte comprising a solvent and a salt (I) comprising a hydroxonium, nitrosonium, ammonium, metal, organic or organometallic cation and a 5-membered (hetero)cyclic anion with the following formula: [Image] X1-X5-N=, -N->-, -C(Y)=, -C->(Y)-, -S(O)(Q)=, -S(Q)= or -P(Q')(Q)=, provided that no more than four comprise N, no more than two comprise S (nonadjacent) and no more than one comprises P; Q', Q : 1-8C perhaloalkyl, perhaloalkenyl or optionally substituted 6-12C aryl or aralkyl, each optionally containing O, S or N heteroatoms; Q : an alkyl, alkenyl, aryl, aralkyl, alkylaryl, alkenylaryl, alicyclic or heterocyclic group optionally substituted with halogen and/or ether, thioether, amine, imine, amide, carboxy, carbonyl, isocyanate, isothiocyanate and hydroxy groups; an aromatic group with ring(s) and/or substituent(s) containing heteroatoms; a polymeric group; or a group having one or more cationic and/or anionic ionophore groups; Y : H, F, Cl, Br, CN, SCN, NCS, NCO, NO2, perfluoroalkyl, perfluoroalkoxy, perfluoroalkylmethyl, tetrafluoroethoxy, SCF3, perfluoroalkylthio, tetrafluoroethylthio, trifluorovinyloxy, trifluorovinylthio, SO2F, SO2Q, COOQ, Q-N-SO2- (sic) or COQ; a group comprising one or more aromatic rings that optionally contain N, O, S or P and are optionally substituted with halogen, CN, CO2, SCN, N3, trifluorovinyloxy, (1-12C perfluoroalkyl)methyl, fluoroalkoxy, fluoroalkylthioxy, alkyl, alkenyl, oxaalkyl, oxaalkenyl, azaalkyl, azaalkenyl, thiaalkyl, thiaalkenyl, polymeric groups and groups having one or more cationic and/or anionic ionophore groups; alternatively, two of Y, Q, Q' and Q can form a 4- to 8-membered ring, or one of Y and Q is a multivalent group attached to a second 5-membered (hetero)cyclic anion, or one of Y and Q is a repeat unit of a polymer; provided that at least one Y or Q comprises a dissociating dipole.