Researchers Hit 96% Efficiency for EV Wireless Charging

­The Oak Ridge National Laboratory may have hit a milestone in over-the-air wireless charging. Researchers managed to wirelessly charge an electric vehicle with an apparent 96% efficiency!

To preserve higher efficiencies, wireless charging tends to stick with the inductive variety, which requires intimate contact at all times.

It’s slowly infiltrated the world of portable consumer electronics, and in fact, I have several wireless charging pads in my home office. But while the concept circumvents cables and plugs, the contact requirement (slightly) tanks the convenience factor.

Enter over-the-air wireless charging, which applies power over RF electromagnetic fields, usually at a steep cost to efficiency.

But a new system at Oak Ridge apparently marries the two concepts.

Researchers placed the charging mat 5 inches away from the vehicle, a Hyundai Kona EV, and managed to apply a 100 kW charge at a previously unheard of 96% efficiency.

“The polyphase electromagnetic coupling coil’s lightweight and small design allows for the highest power density within the smallest coils possible. Rotating magnetic fields generated by the coil phase windings boost the power,” claims the lab.

According to the ORNL’s Omer Onar, their tech reaches power densities 8-10 times higher than conventional coil technology and can increase battery charge state by 50% in under 20 minutes.

“We’ve achieved the highest power density in the world for a wireless charging system for this class of vehicle,” he said. “This is a breakthrough achievement and opens the door to fast and efficient wireless charging for passenger electric vehicles.”

Needless to say, this could revolutionize the very idea of EV charging.