Device to be Charged, Wireless Charging Method and System

The present disclosure discloses a device to be charged, and a wireless charging method and system. The device to be charged includes: a battery; a wireless receiving circuit, configured to receive an electromagnetic signal transmitted by a wireless charging device, and to convert the electromagnetic signal into an output voltage and an output current of the wireless charging circuit; a step-down circuit, coupled between the wireless receiving circuit and the battery, and configured to receive the output voltage of the wireless receiving circuit and to perform step-down processing on the output voltage; a detection circuit, configured to detect a voltage and/or a current entering the battery; and a control circuit, configured to communicate with the wireless charging device according to the voltage and/or the current detected by the detection circuit, so as to enable the wireless charging device to adjust a transmitting power of the electromagnetic signal.