NOVELTY - Electrostatic spinning method for preparing spongiform Nafion membrane comprises dissolving N,N-dimethylacetamide in polyacrylonitrile, then dissolving 10% Nafion (RTM: Sulfonated tetrafluoroethylene based fluoropolymer-copolymer) in the solution to obtain spinning solution containing 5-15 wt.% polyacrylonitrile, placing the spinning solution on a magnetic stirrer for 24 hours until the solution is clear, taking the solution in a syringe and electrospinning via electrostatic spinning device at a voltage of 10-15 KV to obtain Nafion membrane.    USE - The electrostatic spinning method is useful for preparing spongiform Nafion membrane (claimed).    ADVANTAGE - The method reduces the membrane resistance loss, provides desired high surface area and improves battery performance.    DETAILED DESCRIPTION - Electrostatic spinning method for preparing spongiform Nafion membrane comprises: (a) dissolving N,N-dimethylacetamide in polyacrylonitrile, then dissolving 10% Nafion (RTM: Sulfonated tetrafluoroethylene based fluoropolymer-copolymer) in the solution to obtain spinning solution containing 5-15 wt.% polyacrylonitrile; (b) placing the spinning solution on a magnetic stirrer for 24 hours until the solution is clear, taking the solution in a syringe and electrospinning via electrostatic spinning device at a voltage of 10-15 KV to obtain Nafion membrane; (iii) fixing the Nafion membrane between the glass plates, drying under vacuum at 130 degrees C for 5 hours, taking the dried membrane as receiving device, carrying out electrostatic spraying of 20% Nafion solution for 30 minutes, allowing it to stand at room temperature for 2 hours, vacumm drying at 130 degrees C for 40 minutes, repeating electrostatic spraying for 30 minutes, vacuum drying and treating thermally to complete mechanical strengthening of the membrane; and (iv) treating the membrane sequentially with isopropanol, 5% hydrogen peroxide at 80 degrees C, 0.5 mol/l sulfuric acid solution at 80 degrees C and deionized water at 80 degrees C for 0.5 hour to remove impurities, then drying under vacuum.