Electromagnetic induction charging: The primary coil has a certain frequency of alternating current and generates a certain current in the secondary coil clock through electromagnetic induction, thereby transferring energy from the transmission end to the receiving end. At present, the most common charging pad solution adopts electromagnetic induction. In fact, electromagnetic induction solutions do not have much mystery in the realization of technology. The Chinese local BYD company applied for contactless induction as early as December 2005. The charger patent uses electromagnetic induction technology.