(EP948827-A1)      A fuel cell (10) element comprises a polymer electrolyte membrane (18) composed of polystyrene sulphonic acid and polyvinylidene fluoride.    A method of decreasing methanol crossover rate in a methanol-based fuel cell (10) comprises crosslinking and polymerising a polymer precursor to form a membrane, sulphonating the membrane and using the membrane (18) in an electrochemical reaction in the fuel cell.    The electrical performance of a fuel cell (10) having an anode (14), a cathode (16) and a polymer electrolyte membrane (18) is enhanced by circulating oxygen (26) around the cathode (16) at a flow rate less than 5 l/minute.    The polymer membrane used as matrix for crosslinking and polymerisation is a polystyrene sulphonic acid/polyvinylidene polymer membrane or a PTFE membrane, optionally blended with polyvinyl pyrrolidone, polyvinyl alcohol, optionally blended with polyacrylonitrile, polyvinyl chloride, polyacrylamide, polyethylene oxide, polypropylene, polyethylene, polysulphone, sulphonated polysulphone, polyether sulphone, polyetherimide, polymethyl sulphoxide or polyacrylonitrile membrane, glass hollow fibre membrane composite or a ceramic or zeolite matrix host.    The methanol fuel cell (10) includes a pump (20) moving the methanol (23) to contact the anode (14). The flow rate of oxygen (26) in the cathode compartment (28) is 0.003-2.2 l/minute.    USE -   The membrane (18) is used in a liquid feed fuel cell or in a direct methanol fuel cell (10) undergoing an oxidation/reduction fuel cell reaction with methanol as the active element.    ADVANTAGE -   The membrane enhances efficiency of the fuel cell by decreasing permeation of organic fuel, e.g. methanol.    (JP2001504636-W)      A fuel cell (10) element comprises a polymer electrolyte membrane (18) composed of polystyrene sulphonic acid and polyvinylidene fluoride.    A method of decreasing methanol crossover rate in a methanol-based fuel cell (10) comprises crosslinking and polymerising a polymer precursor to form a membrane, sulphonating the membrane and using the membrane (18) in an electrochemical reaction in the fuel cell.    The electrical performance of a fuel cell (10) having an anode (14), a cathode (16) and a polymer electrolyte membrane (18) is enhanced by circulating oxygen (26) around the cathode (16) at a flow rate less than 5 l/minute.    The polymer membrane used as matrix for crosslinking and polymerisation is a polystyrene sulphonic acid/polyvinylidene polymer membrane or a PTFE membrane, optionally blended with polyvinyl pyrrolidone, polyvinyl alcohol, optionally blended with polyacrylonitrile, polyvinyl chloride, polyacrylamide, polyethylene oxide, polypropylene, polyethylene, polysulphone, sulphonated polysulphone, polyether sulphone, polyetherimide, polymethyl sulphoxide or polyacrylonitrile membrane, glass hollow fibre membrane composite or a ceramic or zeolite matrix host.    The methanol fuel cell (10) includes a pump (20) moving the methanol (23) to contact the anode (14). The flow rate of oxygen (26) in the cathode compartment (28) is 0.003-2.2 l/minute.    USE -   The membrane (18) is used in a liquid feed fuel cell or in a direct methanol fuel cell (10) undergoing an oxidation/reduction fuel cell reaction with methanol as the active element.    ADVANTAGE -   The membrane enhances efficiency of the fuel cell by decreasing permeation of organic fuel, e.g. methanol.