| 主权项 |
1. A nonaqueous electrolyte secondary battery comprising:
a quadrilateral battery case; a flat wound electrode body that is accommodated in the quadrilateral battery case, the flat wound electrode body being formed by making an elongated belt-shaped positive electrode and an elongated belt-shaped negative electrode overlap each other with an elongated belt-shaped separator interposed therebetween to obtain a laminate and winding the laminate in a longitudinal direction of the positive electrode and the negative electrode, in which the flat wound electrode body has a flat portion, a first R portion, and a second R portion, the flat portion has a flat surface and is provided in a center portion in a longitudinal direction of a section of the electrode body perpendicular to a winding axis, the first R portion and the second R portion have a curved surface and are provided in opposite end portions, between which the flat portion is interposed, in the longitudinal direction of the section, the second R portion is provided on a bottom side of the quadrilateral battery case, and opposite end portions of the second R portion in a winding axial direction are squashed in a thickness direction of the electrode body to a larger extent than opposite end portions of the first R portion in the winding axial direction; and a nonaqueous electrolytic solution that is accommodated in the quadrilateral battery case. |
