Charging a device without the need for electrical cords or charging cradles it stepping closer to reality, with a new method being tested out successfully. The method is termed quasistatic cavity resonance (QSCR). For a recent trial, a research team successfully produced near-field standing magnetic waves. These waves rapidly filled the interior of a room (16-by-16-foot) and allowed a range of standard consumer electronic products to be charged. The only catch was that the room need to be constructed entirely from metal (aluminium).
In the trial, the generated waves were sufficient to power-up several cellphones, as well as to operate fans and to power lights simultaneously. The researchers managed to transmit 1.9 kilowatts of power, which would be sufficient to charge 320 smartphones at the same time. The next wave of research will look at downscaling the device to power a child’s toy chest and to upscale the wave generator to power a warehouse.
The video below explains more about the technology:
The QSCR technique works by inducing electrical currents into metalized walls, floors and ceilings in a room. Following this, uniform magnetic fields are generated and these permeate the room’s interior. This penetration allows for power to be transmitted efficiently to receiving coils. The coils are designed to operate at the same resonant frequency as the magnetic fields. The induced currents in the structure are then channeled through discrete capacitors (which function to isolate potentially harmful electrical fields).
The Wi-Fi charginbg method has been described in the journal PloS One and the research paper is called “Quasistatic Cavity Resonance for Ubiquitous Wireless Power Transfer.”
