wireless energy transfer


wireless energy transfer

The transfer of power to a device without wires. Although the wireless transfer of electromagnetic energy in the form of audio, video and data signals is ubiquitous, the wireless transfer of electrical power is relatively new.

Inductive Charging
Some devices already employ wireless energy transfer without the use of metal contacts. Known as "inductive charging," power is transferred through the plastic cases using magnetic induction; however, the device must be dropped into a charging base or placed on a charging mat. See Qi and AirFuel.

Resonance Charging
Magnetic resonance chargers charge batteries in low-power devices that are close but do not have to touch. As soon as a device is within range, data signals activate the charging. The farther the distance between device and charger, the longer the charging time. See AirFuel.

The Future
By using magnetic fields, some time in the future, electric vehicles are expected to be refueled within three feet of the charging station.

No Metal Contacts
With inductive transfer, power is transferred without a metal plug and socket. The toothbrush is dropped into its charging base, and the smartphone rests on its base (see Palm Pre).


No Metal Contacts
With inductive transfer, power is transferred without a metal plug and socket. The toothbrush is dropped into its charging base, and the smartphone rests on its base (see Palm Pre).


Wireless Power in the Car
In 2013, iOttie debuted the Easy Flex system for certain smartphones. The dashboard mount (top) is wired to the car's power, and an antenna coil (bottom) is lined up with the phone's internal battery terminals.