NOVELTY - Fluoro-olefins of specified formula are new.    USE - As monomer precursors to the polymers and ionomers. It is also used in acid form, super acid catalysts for reactions such as friedel-krafts alkylation. In Electrochemical Cells (e.g. batteries, fuel cells, electrolysis cells, ion exchange membranes, sensors, electrochemical capacitors and modified electrodes, particularly in lithium batteries). The polymers are useful in the formation of films and coatings.    ADVANTAGE - The polymers obtained show high chemical resistance and good physical properties. Better processability at some cost to chemical and thermal stability. The ionomers have high labile cations having reduced fluorine content.    DETAILED DESCRIPTION - Fluoro-olefins of formula (I) are new:    n = 1 - 5.    INDEPENDENT CLAIMS are also included for the following:    (A) an ionizable olefinic composition of formula (II);    (B) synthesizing (I) which comprises:    (a) contacting CF2ClCFCl(CF2CF2)nI with Na2S2O4 and NaHCO3 in a mixture of water and an aprotic polar solvent (1) in the temperature range from room temperature 110 degreesC to form CF2ClCFCl(CF2CF2)nSO2Na;    (b) contacting the product of step (a) with Cl2 in water or in a mixture of water and (1) in the temperature range from 0 - 200 degreesC to form CF2ClCFCl(CF2CF2)nSO2Cl;    (c) contacting the product of step (b) with a univalent metal fluoride in an anhydrous aprotic polar solvent to form CF2ClCFCl(CF2CF2)nSO2F;    (d) contacting the product of step (c) with zinc in an alcohol or a mixture of acetic acid and alcohol to form (I); and    (e) separating the product;    (C) a polymer which comprises monomer units (0.1 - 50 mol. %) of formula (III);    (D) an ionomer which comprises monomer units of vinylidene fluoride and monomer units (0.1 - 50 mol%) of formula (IV);    (E) formation of an ionizable composition comprises contacting a composition comprising the functional group -(CF2CF2)n-SO2F with a solution of an alkali metal salt at 85 degreesC. The pH of the solution should not exceed 13 till the alkali metal sulfonate form of the polymer is obtained;    (F) an ionically conductive composition comprises (II), (III) or (IV) and a liquid (2) imbibed;    (G) an electrode comprises at least one electrode active material and (III) or (IV); and    (H) an electrochemical cell comprises a positive electrode, negative electrode, separator disposed between the positive and negative electrodes. A means for connecting the cell to an outside load or source where at least one of separator, cathode and anode comprises (III) or (IV).    M = univalent metal.    X = F or -OM;    M = univalent metal or hydrogen.    p = 1 - 10.