NOVELTY - A redox flow battery comprises cathode cell (1) comprising cathode (13), catholyte, and bipolar plate, anode cell (2) comprising anode (14), anolyte, and bipolar plate, and ion exchange membrane (100) interposed in cathode cell and anode cell comprising porous substrate and polymer disposed in pores of porous substrate in which greater than or equal to 1 cathode and anode comprises carbon-coated metal foam, and polymer is polymerization product of composition for preparing ion exchange membrane comprising 1st aromatic vinyl monomer containing halogenated alkyl group or quat.-ammonium group.    USE - Redox flow battery for mobile phones and mobile computers. Can also be used for device with high capacity and high power output such as an electric vehicle, and for hybrid vehicle in combination with internal combustion engine, fuel cell, and super-capacitor.    ADVANTAGE - The battery has improved electrode specific surface area and electrochemical properties, reduced internal resistance, entire weight, and durability, and increased energy efficiency, and avoids thickness and mechanical processing e.g. cutting of carbon bipolar plate.    DETAILED DESCRIPTION - A redox flow battery comprises cathode cell comprising cathode, catholyte, and bipolar plate, anode cell comprising anode, anolyte, and bipolar plate, and ion exchange membrane interposed in cathode cell and anode cell comprising porous substrate and polymer disposed in pores of porous substrate in which greater than or equal to 1 cathode and anode comprises carbon-coated metal foam, polymer is polymerization product of composition for preparing ion exchange membrane comprising 1st aromatic vinyl monomer containing halogenated alkyl group or quat.-ammonium group, and bipolar plate comprises greater than or equal to 1 metal which is nickel (Ni), copper (Cu), iron (Fe), chromium (Cr), aluminum (Al), tungsten (W), titanium (Ti), and their alloy.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of redox flow battery.    Cathode cell (1)    Anode cell (2)    Cathode (13)    Anode (14)    Ion exchange membrane (100)