Wireless charging, also known as non-contact inductive charging, is the use of near-field induction, that is, inductive coupling, by the power supply device (charger) to transmit energy to the electrical device, the device uses the received energy to charge the battery, and at the same time for its own operation.
Because the charger and the electrical device are inductively coupled to transmit energy, the two are not connected by wires, so the charger and the electrical device can be non-conductive contact exposed, it just means that the phone and the charger are not connected by wires, but still need electricity, so it also needs electricity.