Patent ID: 8367245

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 porous heat-resistant layer interposed between said positive electrode and said negative electrode, and a non-aqueous electrolyte, said positive and negative electrodes being wound with said separator and said porous heat-resistant layer, said negative electrode comprising a negative electrode current collector and a negative electrode mixture layer on a surface of said negative electrode current collector, said negative electrode mixture layer having an active material density of 1.5 g/ml to 1.8 g/ml, said porous heat-resistant layer being carried on said negative electrode, and said porous heat-resistant layer comprising magnesium oxide particles having a mean particle size of 0.5 μm to 2 μm, wherein said porous heat-resistant layer contains 1 to 5 parts by weight of a binder per 100 parts by weight of said magnesium oxide particles, and said porous heat-resistant layer has a thickness of 1 μm to 5 μm.