NOVELTY - Monoanions (I) and (II) having a transition metal or Group III, IV or V element bound to a fluorinated alcohol, thioalcohol or amine ligand are new.    USE - The anions (I) and (II) are useful as electrolytes for electrochemical devices (claimed), e.g. batteries (especially lithium batteries or lithium ion batteries), fuel cells, electrical double layer capacitors, sensors and electrochromic displays. The anions can also be used as co-catalysts for activating transition metal-catalyzed polymerization and as counterions for polymerization photoinitiators.    ADVANTAGE - The polyfluorinated anions are weakly associating and have good thermal, hydrolytic and electrochemical stability. The compounds, especially lithium salts, have high conductivity, possibly due to the lithium ion being weakly bonded to several alkoxide oxygen atoms and fluorine atoms.    DETAILED DESCRIPTION - Monoanions of formulae (I) and (II) are new.    M1 = a transition metal (excluding copper) or a Group III, IV or V element;    Z = O, S or NR6R7;    X = halide;    R1 = a bond or 1-4C alkylene;    R2, R3, R4 = H, F, optionally fluorinated 1-10C alkyl, optionally fluorinated 4-20C aryl or optionally fluorinated 3-10C cycloalkyl provided at least one of these groups is F or a fluorine-containing group;    R5 = fluorinated 1-10C alkyl, fluorinated 4-20C aryl, optionally fluorinated 4-20C aryloxide or optionally fluorinated 1-10C alkoxide;    R6, R7 = H or 1-10C alkyl;    a, b, c = 0-4; provided that    a + b + c = 2-8.    When R2 = fluorinated 1-4C alkyl, R1 = a bond, b and c = 0, and R3 = optionally fluorinated 1-10C alkyl, then R4 = F, fluorinated 1-10C alkyl or fluorinated 4-20C aryl.    M2 = a transition metal or Group III, IV or V element;    L = a halide, optionally fluorinated 1-10C alkyl, optionally fluorinated 4-20C aryl or -Z3R11;    d = 0-4;    e = 1-3;    d + e = 1-6;    n = 1 or 2;    Z1, Z2, Z3 = O, S or NR6R7;    R8, R10 = a bond or -(CR12R13)x-;    x = 1-4;    R9 = optionally fluorinated or substituted 1-30C alkylene, optionally fluorinated 3-10C cycloalkylene or optionally fluorinated 4-20C arylene;    R11 = 1-10 alkyl or 4-20C aryl (both optionally substituted);    R12, R13 = H, F or optionally fluorinated 1-4C alkyl.    The provisos are given that: at least one of R8 and R10 = CR12R13; and that at least one of R12 and R13 = F or fluorinated 1-4C alkyl.