Cylindrical secondary battery including corrosion prevention layer

The present specification relates to a cylindrical secondary battery comprising a corrosion prevention layer, the cylindrical secondary battery comprising: a gel roll-type electrode assembly having a structure in which a first electrode, a second electrode, and a separation membrane interposed therebetween are wound in one direction about a winding axis; a battery can containing the electrode assembly and including a metal plating layer; a bonding lead plate that bonds the battery can and the electrode assembly; and a corrosion prevention layer disposed at a portion where the outer surface of the battery can is damaged in a welded portion formed by melting the bonding lead plate on the outer bottom surface of the battery can and the battery can. 本说明书涉及包括腐蚀防止层的圆筒形二次电池，该圆筒形二次电池包括：包括：凝胶卷型的电极组件，其具备第一电极、第二电极及介于它们之间的分离膜以卷取轴为基准向一个方向卷取而成的结构；电池罐，其收纳上述电极组件且包括金属镀覆层；接合引线板，其将上述电池罐和电极组件接合；及腐蚀防止层，其在上述电池罐的外部底面的上述接合引线板和上述电池罐熔化而形成的焊接部中配置在上述电池罐的外部表面受损的部位。