POLYMER ELECTROLYTE COMPOSITE FILM, METHOD FOR PRODUCTION THEREOF AND USE THEREOF

A polymer electrolyte composite film which comprises a porous base material and, provided in fine pores thereof, a polymer electrolyte comprising a hydrophilic moiety and a hydrophobic moiety, the hydrophilic and hydrophobic moieties of said polymer electrolyte satisfy the following formula (1): a + b ≤ d (1) [wherein, a represents the size of a hydrophobic domain (nm), b represents the size of a hydrophilic domain (nm), and d represents the average pore diameter (nm) of fine pores of the porous base material].