BMW and Mercedes-Benz are collaborating to provide wireless charging for their next series (and classes) of electric cars. Under their R&D microscopes is a new magnetic-resonance charging system that eventually may replace wired Level 2 stations altogether. This system of weathered, sealed coils and synchronized magnetic frequencies is an improved variation of inductive charging that has been around for more than a century.
With the system, there’s no need to plug in your plug-in car anymore. In a nutshell, you park your Bimmer (or Benz) over a small lump in the driveway or garage, a Wi-Fi connection talks to the transmitter and the receiver mounted underneath the car, and in a few hours the battery is topped off. Compared to BMW’s solar-powered carport designed to show off a driver’s bamboo proclivities, this setup is entirely demure and practical. The BMW/Benz system is currently rated at 3.6 kW, which could fully charge a BMW i8 in less than two hours, and eventually will hit 7 kW, or slightly more than what a new Nissan Leaf can gulp in a single hour. Mercedes says it will eventually offer wireless charging on the upcoming S500 Plug-in Hybrid while BMW will bring it to the i3, i8, and more plug-in hybrids such as the X5 Plug-in.
Toyota has already been working on a similar wireless setup for the next-gen Prius Plug-in, and Nissan has been talking about one for the Leaf for even longer. Although BMW and Mercedes claim more than 90-percent efficiency, magnetic-resonance charging still requires the driver to pinpoint his parking job and for the pads to be as close together as possible. It’ll still work with impatient people who hurry into a space, just not as well. And should the family cat scurry into the magnetic field, it’s supposed to shut down.
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The German brands don’t usually hold hands, but they do loosen up when it comes to standardizing new technologies (such as the SAE’s fast-charge combo plug that BMW, Mercedes, and several other automakers support). Other companies, such as Hevo Power, are trying to embed wireless chargers into city streets, and still others want to replace electrical outlets in our homes with the same concept.
Clifford Atiyeh is a reporter and photographer for Car and Driver, specializing in business, government, and litigation news. He is president of the New England Motor Press Association and committed to saving both manuals and old Volvos.
