A hybrid vehicle includes an engine, a motor generator configured to control the revolution speed of the engine, and an ECU configured to control ignition timing of the engine. The copper foil is provided with an oxide film having a thickness of 50 \u212b to 350 \u212b on a surface in contact with the bump and an insulating layer. Two cases 2, 3 have a close state in which they are overlapped mutually and an open state in which the upper case 2 is extended by moving in a predetermined direction.