A cell including an electrode assembly, a packaging bag, an inner electrode tab, and an outer electrode tab. The packaging bag includes a main body and an edge sealing portion, the electrode assembly and the inner electrode tab being received in the main body. The edge sealing portion is connected to a top wall of the main body, the other end of the outer electrode tab extends out of the packaging bag from the edge sealing portion. The top wall includes a first portion and a second portion disposed on both sides of the edge sealing portion in the thickness direction of the cell. A height from the first portion to a bottom wall of the main body is less than a height from the second portion to the bottom wall.