Wireless charging is becoming more and more common, and even more standardized. It is set to become more popular with the adoption of Qi wireless charging in Apple’s iPhone 8, iPhone 8 Plus, and iPhone X. It’s also found on some Android phones, like Samsung’s Galaxy Note 8, Galaxy S8, and Galaxy S7. Most wireless chargers use magnetic induction and magnetic resonance. They offer the promise of being able to place a device on a surface and have it charge automatically—no fiddling with cables required.
How Wireless Charging Works
Wireless chargers typically use magnetic induction. The short explanation is that they use magnetism to transmit energy. First, you place the device on the wireless charger. The current coming from the wall power outlet moves through the wire in the wireless charger, creating a magnetic field. The magnetic field creates a current in the coil inside the device sitting on the wireless charger. This magnetic energy is converted to electrical energy, which is used to charge the battery. Devices must have the appropriate hardware in them to support wireless charging. A device without the necessary coil can’t charge wirelessly.
Wireless charging is enabled through three different forms:
Inductive Charging: Uses electromagnetic waves to transfer energy and charge devices wirelessly. Inductive charging requires the device to be placed on a conductive charging pad/equipment, which is directly connected to a wall socket. It is mainly used to charge small hand-held devices such as, smartphones, PDAs and mobile phones.
Radio Charging: Similar to inductive charging, radio charging use wireless radio waves to transfer energy to small devices and equipment. The device is placed on a radio wave emitting transmitter that transmits radio waves to charge the device.
Resonance Charging: Used for charging large devices and equipment such as laptops, robots, cars and more. It consists of a sending (sender) copper coil and a receiving (receiver) copper coil at the device end. The sender and receiver must configure the same electronic magnetic frequency to transfer electrical energy.