SECONDARY BATTERY

A secondary battery of sealed structure disclosed herein is provided with a stacked electrode body inside a battery case. At a region closer to a lid body of the battery case when a rectangular positive electrode sheet and rectangular negative electrode sheet that make up the electrode body is bisected with respect to a direction from the lid body to a bottom surface of a case body, a positive electrode collector exposed portion and a negative electrode collector exposed portion, which do not have a positive or negative electrode active material layer, are formed, in the rectangular positive electrode sheet and negative electrode sheet, on the inward side of the rectangular positive and negative electrode sheets, in such a manner that one side of each exposed portion makes up part of an edge, of the positive and negative electrode sheets, neighboring and opposing the lid body.