Secondary battery

Abstract

According to the present disclosure, a secondary battery in which precipitation of metallic lithium can be inhibited more appropriately is provided. The secondary battery disclosed here includes a flat wound electrode body. The wound electrode body has a pair of curved portions and a flat portion. In addition, a positive electrode starting end portion inside the wound electrode body has a first region extending along the flat portion. On the other hand, a negative electrode starting end portion inside the wound electrode body has a second region extending along the flat portion, a folded portion folded back along a first curved portion, and a third region extending from the folded portion along the flat portion. In addition, in the wound electrode body, an electrode starting end stacked portion in which the first region, the second region, and the third region overlap each other is formed in a part of the flat portion, and a positive electrode terminating end portion and a negative electrode terminating end portion are disposed in the first curved portion. According to such a configuration, a local pressing failure and non-uniform heat generation distribution can be appropriately prevented, and the precipitation of metallic lithium can be inhibited.