A portable electronic apparatus includes first and second modules, and a control unit. The first module includes a first charging circuit to be coupled to a first power source, and a first battery unit coupled to the first charging circuit. The second module is connected removably to the first module, and includes a second charging circuit to be coupled to a second power source, and a second battery unit coupled to the second charging circuit. The control unit enables the first and second battery units to be charged independently and respectively through the first and second charging circuits using the first and second power sources when the second module is disconnected from the first module, and enables the first and second battery units to be charged through the first charging circuit using the first power source when the second module is connected to the first module.