A battery pack includes a housing, at least one battery cell housed in the housing, a wireless transmitter housed in the housing, a button that initiates a pairing with an electronic device so that the battery pack may wirelessly communicate with the electronic device through the wireless transmitter, a connection section including a first electrical connector configured to supply power to a power tool and a charging port configured to supply power to an external device. The charging port can be in an on state in which the charging port is operable to supply power to the external device and an off state in which the charging port is not operable to supply power to the external device.