A cell includes a flat electrode assembly formed by superposing and winding respective first ends of a first electrode sheet, a first separator, a second electrode sheet, and a second separator. A first electrode tab is connected to the first electrode sheet, and a second electrode tab is connected to the second electrode sheet. The second electrode sheet includes a second current collector, a second outer membrane arranged on a surface facing away from a center of the cell, and a second inner membrane arranged on a surface facing the center of the cell. Respective starting ends of the second outer membrane and the second inner membrane are located on the second current collector between the first end of the second electrode sheet and a second bend. The second inner membrane is provided with an inner uncoated region at least at the second bend.