An outer insulation member made of a first resin packs a part of an anode terminal. The packed part of the anode terminal has a predetermined section. All surfaces of the predetermined section consist of a front surface, a back surface and edges connecting between the front surface and the back surface. The front surface includes a connection area. An anode lead wire is connected to the connection area while being not connected to the anode terminal other than the connection area. The all surfaces of the predetermined section are completely covered with a mask layer made of a second resin except for the connection area. The second resin is different from the first resin in at least one of composition thereof, content of an inclusion, size of an inclusion and shape of an inclusion.