Method of manufacturing battery

A method of manufacturing a battery including a wound electrode assembly, the method comprising the steps of:

• (A) winding a first separator, a second separator, a positive electrode plate, and a negative electrode plate onto a first winding core disposed at a first position;
• (B) moving the first winding core away from the first position and disposing another a second winding core at the first position;
• (C) cutting the first separator and the second separator wound on the first winding core that is moved away from the first position, wherein the first separator and the second separator and stacked and retained on the outer circumferential surface of the second winding core disposed at the first position in the step (B), wherein the second winding core has a groove provided along an axial direction on its outer peripheral surface, and in step (C) the groove is included in the region where the first separator and the second separator are stacked around the winding core, and cutting the first separator and the second separator on the groove of the outer circumferential surface of the second winding core;
• and
• (D) winding the first separator and the second separator onto the first winding core moved away from the first position in step (B) up to a cut edge portion at which the first separator and the second separator are cut in step (C).