Patent ID: 8003259

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 adhering 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 a void capable of retaining said non-aqueous electrolyte is formed on an adhering interface where said porous insulating film adheres to said electrode surface, said void having a size of 1 to 4 μm, the amount of said film binder contained in said porous insulating film is not greater than 4 parts by weight per 100 parts by weight of said inorganic oxide filler, a void size distribution of said negative electrode and said porous insulating film measured by a mercury intrusion porosimeter has a peak in a region ranging from 1 to 4 μm and said electrode surface to which said porous insulating film adheres has an average surface roughness Ra of 0.1 to 1 μm.