Patent ID: 7422825

Claim:
A non-aqueous electrolyte secondary battery comprising: a positive electrode; a negative electrode; a separator interposed between said positive electrode and said negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of said positive electrode and said negative electrode, said porous insulating film comprising an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of said separator is not less than 0.4 and not greater than 0.7, a porosity P of said porous insulating film is not less than 0.35 and not greater than 0.65, and wherein said ratio R and a porosity P of said porous insulating film satisfy the relational formula: −0.10 ≦R−P≦ 0.30.