Secondary battery and method for manufacturing the same

Abstract

A secondary battery that includes a wound electrode assembly in which a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode are wound about a winding axis; and a current collecting tab at a first end of the wound electrode assembly along a direction of the winding axis, wherein the wound electrode assembly has a separator extension portion in which the separator extends more than the positive electrode and the negative electrode toward a second end of the wound electrode assembly along the direction of the winding axis, the second end being opposite the first end, and the separator has a bent shape that protrudes toward an outer peripheral side of the wound electrode assembly at least at a part of the separator extension portion in a sectional view passing through the winding axis.

Dependencies are inferred from the claim text.