A charge pump IC and LDO are provided between the main power supply of a portable electronic device and a supplemental battery to control charge current and voltage to the supplemental battery using a small internally-packaged circuit. In addition, the deposit managing unit 22 prohibits the game player from using the virtual currency deposited by the game player until a predetermined deposit period expires. The system allows a user to rate content, and to be notified when that content is being played on any station. The retaining members can be welded to the equipment to be protected and retain the wear members which are not readily welded. In another embodiment, the heat treatment may comprise subjecting the formed steel composition to austenizing, quenching, and tempering a selected number of times.