A battery charging method and an electronic device are disclosed. The electronic device can comprise: a connection unit comprising a first terminal to which a voltage is applied by an external device, and a second terminal for transmitting/receiving data; a first charging unit for charging a battery connected to the electronic device by using the voltage applied to the first terminal; and a second charging unit for charging the battery by dropping the voltage applied to the first terminal according to a preset voltage drop rate. The first charging unit can comprise: a first switch connected to the first terminal; a communication unit for transmitting information through the second terminal; and a first control unit for acquiring first information on the battery voltage, controlling the communication unit such that the first information is transmitted to a charger connected to the connection unit, and controlling the first switch such that the voltage adjusted on the basis of the first information by the charger is supplied to the second charging unit through the first terminal.