A coin-shaped battery having a structure of improving a discharge capacity and preventing the deposition of lithium metal. A group of pole plates (1), formed by bending an anode plate (7) and a cathode plate (8) at a connection piece and coiling them flat so that the laminate surface of the anode plate (7) and that of the cathode plate (8) are layered one upon another via a separator (9), is housed in a battery case having the opening of a cap case (4) sealed by a sealing case (5). An insulating member is provided on the surface facing the end of the cathode plate (8) of the connection piece positioned in the center of the coiled anode plate (7).