A battery includes an electrode assembly defining a core and an outer circumference by winding a first electrode, a second electrode, and a separator interposed therebetween around a winding center, each of the first electrode and the second electrode includes a first uncoated portion and a second uncoated portion on which an active material layer is not coated along the winding direction; a battery housing accommodating the electrode assembly through an opening formed on one side thereof; a cap including a venting portion, covering the opening, and electrically connected to the battery housing and the first uncoated portion; and a battery terminal penetrating one surface of the battery housing and electrically connected to the second uncoated portion.