The purpose of the present invention is to prevent inconsistency in current collection efficiency by integrating current collector terminals using two active material retention sections which retain active materials, to simplify welding operations by reducing the number of current collector terminals, and to simplify the operation of stacking multiple electrode plates. Specifically, the present invention provides a stacked electrode assembly (3) including a positive plate (31), a negative plate (32) and a separator (33). The positive plate (31) is formed substantially in a U-shape such that two active material retention sections (31B) for retaining cathode active materials are arranged opposite each other, and the negative plate (32) is formed substantially in a U-shape such that two active material retention sections (32B) for retaining anode active materials are arranged opposite each other. The positive plate (31) and the negative plate (32) are stacked such that at least one active material retention section (31B) in the positive plate (31) is interposed between the two active material retention sections (32B) in the negative plate (32).