R&D 100 winner of the day: Polyphase electromagnetic couplers for extreme fast wireless charging of electric vehicles

Current wireless charging technology for electric vehicles is limited by the bulky and heavy nature of high-power systems. While light-duty vehicles are limited to 11 kW charging, systems capable of 100 to 250 kW are too large for practical use, even in heavier vehicles. This new wireless charging technology development from Oak Ridge National Laboratory offers a solution by significantly increasing power density while reducing size and weight. Co-develoepd with Volkswagen Group of America, Volkswagen Group Innovation, Volkswagen Group Components, and Hyundai-Kia North America Technical Center, the technology achieves a surface power density of up to 1,530 kW/m2, an 8 to 10-fold increase compared to existing systems, making it a transformative leap in wireless power transfer. Furthermore, the new technology addresses concerns about electromagnetic field emission. Using a polyphase design, the system operates below international guidelines and standards, minimizing energy losses and boosting efficiency to over 95%, compared to existing systems operating between 85 and 92%. Polyphase wireless charging is an enabling technology for high-power wireless electric vehicle (EV) charging systems that can achieve the highest power transfer levels with the most compact and lightweight coils possible in the world. This technology reduces the charge duration of electric vehicles down to 10-15 minutes.