The United States Department of Energy, through its Oak Ridge National Laboratory and its management company UT-Battelle, has filed a patent to use graphene for more efficient high frequency coils, also known as Tesla coils. The graphene would wrap around the wires of the coil to act as protection against unwanted eddy currents, making such coils more suitable for wireless power transmission.
United States Patent Application number 20130020877 relates to the field of wireless power transfer, and in particular to graphene-coated coupling coils for reducing alternating current (AC) resistance for high frequency AC applications. Wireless transmission of electrical energy has been a goal of engineers ever since the Serbian-American scientist Nikola Tesla dreamed it up a century ago. Practical and commercial realization of wireless power has been elusive, but hopefully this patent brings us a step closer to charging our mobile devices out of thin air.
The problem that the inventors attempt so solve is that of eddy currents, which are parasitic electrical currents that creep up into wires carrying high-frequency alternating currents, in particular when several such wires are near each other. The problem is solved by wrapping the wires in graphene, which provides a short circuit for the eddy currents, while leaving the AC currents intact. The hope is that lower losses in the circuits used to generate and receive wireless power will result in more efficient transmission of power. The receiver is said to be on a vehicle. Tesla also worked on using these coils for shooting out lightning bolts and wireless communication.
The patent application is a beautiful example of technology catching up to dreams of a scientific genius, aiming to fulfil those dreams a century later. May the invention serve mankind as Tesla would have wanted it to.