Patent ID: 10177411

Abstract:
A nonaqueous electrolyte secondary battery includes: a wound electrode body that is formed by laminating an elongated sheet-shaped positive electrode current collector foil, an elongated sheet-shaped negative electrode current collector foil, and an elongated sheet-shaped separator to obtain a laminate and winding the obtained laminate; a nonaqueous electrolytic solution; and a case that accommodates the wound electrode body and the nonaqueous electrolytic solution. A solid electrolyte interface film derived from an oxalato borate complex is formed on at least a surface of the negative electrode active material layer. The positive electrode current collector foil satisfies the following conditions of (a) 700%≤α≤760% and (b) 530%≤β≤590%, where α represents a 60-degree specular gloss in a direction parallel to a longitudinal direction of the positive electrode current collector foil, and β represents a 60-degree specular gloss in a width direction perpendicular to the longitudinal direction of the positive electrode current collector foil.