Abstract: Battery-powered equipment for detecting the type of battery installed therein, includes a plurality of types of batteries which can be installed in the battery-powered equipment. Each of the batteries has a positive power terminal, a negative power terminal, and first to third detection terminals. The battery-powered equipment includes a battery type detector for detecting the type of an installed battery according to terminal voltages on the first to third detection terminals of the installed battery. The equipment further includes a battery charger for controlling the charging and discharging of the installed battery on the basis of the detected battery type.