Method and apparatus for wireless charging

A wireless power reception device comprising:

• a battery;
• a wireless charging circuit comprising a coil;
• and
• one or more processors operatively connected with the wireless charging circuit,
• wherein the one or more processors are configured to:
• control the wireless charging circuit to receive via the coil, from a wireless power transmission device, a first wireless power corresponding to a first charging voltage induced in the coil,
• control the wireless charging circuit to initiate to charge the battery by using the first wireless power received via the coil,
• while charging the battery based on the first wireless power, control the wireless charging circuit to transmit via the coil, to the wireless power transmission device, a first signal to request wireless charging information with respect to the wireless power transmission device using the wireless charging circuit,
• in response to the transmitting of the first signal, control the wireless charging circuit to receive via the coil, from the wireless power transmission device, the wireless charging information,
• control the wireless charging circuit to transmit via the coil, to the wireless power transmission device, a second signal including information relating to one of at least one voltage supportable by the wireless power transmission device, based on the received wireless charging information,
• after transmitting of the second signal, control the wireless charging circuit to receive, from the wireless power transmission device, a second wireless power corresponding to a second charging voltage induced in the coil,
• control the wireless charging circuit to charge the battery by using the second wireless power received via the coil,
• wherein the second charging voltage is greater than the first charging voltage, and
• wherein the wireless charging information includes information relating to the at least one voltage supportable by the wireless power transmission device.

A method for operating a wireless power transmission device, the method comprising:

• receiving, from a wireless power reception device, a first signal to request wireless charging information related to the wireless power transmission device using a wireless charging circuit while applying a first voltage to a transmission coil of the wireless charging circuit for wirelessly charging the wireless power reception device;
• in response to the receiving of the first signal, transmitting, through the wireless charging circuit to the wireless power reception device, information relating to at least one voltage that is supportable by the wireless power transmission device, as at least part of the wireless charging information;
• receiving, from the wireless power reception device, a second signal including information relating to a second voltage of the at least one voltage using the wireless charging circuit;
• based at least in part on the receiving of the second signal, changing a voltage to be applied to the transmission coil from the first voltage to the second voltage;
• and
• controlling the wireless charging circuit to apply, to the transmission coil, the second voltage to transmit wireless power,
• wherein the second voltage is greater than the first voltage.

A method for operating a wireless power reception device, the method comprising:

• receiving via a coil of the wireless power reception device, from a wireless power transmission device, a first wireless power corresponding to a first voltage applied at the wireless power transmission device;
• initiating to charge a battery of the wireless power reception device by using the first wireless power corresponding to the first voltage,
• while charging the battery based on the first wireless power, transmitting, to the wireless power transmission device, a first signal to request wireless charging information with respect to the wireless power transmission device using a wireless charging circuit;
• in response to the transmitting of the first signal, receiving via the coil, from the wireless power transmission device, the wireless charging information;
• transmitting via the coil, to the wireless power transmission device, a second signal including information relating to a second voltage of at least one voltage, based at least in part on the received wireless charging information;
• after the transmitting of the second signal, receiving, from the wireless power transmission device, a power corresponding to the second voltage applied at the wireless power transmission device;
• and
• charging a battery based on the received power;
• wherein the second voltage is greater than the first voltage, and
• wherein the wireless charging information includes information relating to the at least one voltage supportable by the wireless power transmission device.

A wireless power transmission device comprising:

• a wireless charging circuit comprising a wireless charging coil;
• and
• one or more processors operatively connected with the wireless charging circuit,
• wherein the one or more processors are configured to:
• generate a first power to wirelessly charge a wireless power reception device by applying a first voltage to the wireless charging coil,
• transmit, through the wireless charging circuit, to the wireless power reception device, information relating to a second voltage that is supportable by the wireless power transmission device,
• after the transmitting of the information, receive, from the wireless power reception device, a power change request signal through the wireless charging circuit, and
• in response to receiving the power change request signal, generate a second power to wirelessly charge the wireless power reception device by applying the second voltage to the wireless charging coil, and
• wherein the second voltage is greater than the first voltage.

A wireless power reception device comprising:

• a battery;
• a wireless charging circuit comprising a wireless charging coil;
• and
• one or more processors operatively connected with the wireless charging circuit,
• wherein the one or more processors are configured to:
• obtain, based on a first voltage applied at a wireless power transmission device through the wireless charging coil, a first charging power to charge the battery,
• receive, through the wireless charging circuit from the wireless power transmission device, information relating to a second voltage that is supportable by the wireless power transmission device,
• after the receiving of the information, transmit, through the wireless charging circuit to the wireless power transmission device, a power change request signal, and
• after the transmitting of the power change request signal, obtain, based on a second voltage applied at the wireless power transmission device through the wireless charging coil, a second charging power to charge the battery, and
• wherein the second voltage is greater than the first voltage.