The present disclosure provides a joining technique capable of improving strength and reducing electrical resistance of a connecting portion that performs heterometal interjunction in a sealed battery. A mode of the sealed battery disclosed herein includes an electrode body, a battery case, a positive electrode internal terminal, a positive electrode external terminal, a negative electrode internal terminal, and a negative electrode external terminal. In the sealed battery, in a connecting portion between the negative electrode internal terminal and the negative electrode external terminal, an upper end of the negative electrode internal terminal and the negative electrode external terminal are stacked with a plated layer interposed therebetween and, at the same time, the negative electrode internal terminal and the negative electrode external terminal are joined to each other via the plated layer. In addition, a rough surface having a plurality of recessed portions is formed on the upper surface of the negative electrode external terminal having been stacked with the plated layer interposed therebetween, and a part of the plated layer penetrates into the recessed portions. Accordingly, a connecting portion having high strength and low resistance can be formed between the negative electrode internal terminal and the negative electrode external terminal.