SAE Agrees On New Wireless Charging Standard

Uniform technical standards are critical to the adoption of any new technology. Just imagine if every appliance manufacturer used plugs of its own design. Our homes would need a half a dozen types of electrical outlets and a welter of adapters in order to function. Having a standard design means we don’t even have to think about how to plug in our appliances. Wireless charging for EVs is a great idea, but until now it has been hampered by a lack of agreed technical standards.

wireless charging for EVs

Not anymore. At a conference of automotive manufacturers and suppliers at Audi headquarters in Ingelstadt, Germany, last week, it was announced that all parties and interested stakeholders have agreed to the new J2954 standard proposed by SAE International for wireless charging equipment. The agreement paves the way for wireless charging equipment of the future to have a high degree of interoperability between brands and in various countries. The standard should make wireless charging less expensive and more appealing to a wide range of drivers.

Developing standards does not happen overnight. The SAE wireless charging project has been ongoing since 2010. It was only after years of input from manufacturers and automotive suppliers that an agreement on what the technical standard should be was reached.

Ultimately, wireless charging will allow EV drivers to simply park their cars over a designated spot and walk away. Their cars will charge automatically while they are gone without needing to be connected to a charging cable. The autonomous cars of the near future will be able to park themselves in public lots, drive themselves to an available wireless charging location, then return to an open charging space when recharging is complete.

WiTricity of Watertown, Massachusetts is one company that is leading the research and development of wireless charging equipment. Initially, the J2954 standard will apply only to systems with 3.7 kW, or 7.7 kW of power, corresponding to today’s Level 1 and Level 2 charging equipment. But WiTricity says it is working on systems that offer 11 kW on up to 22 kW of power. Even higher power levels will be possible in the future. It claims its systems have an efficiency of between 91 and 94% using the circular coil design that is now part of the SAE protocol.

“Our team has pioneered the technology for wireless charging systems that not only deliver the power levels and high efficiency needed for today’s vehicles, but also are very interoperable. Our automaker customers want to know that their cars will work with charging stations around the world, and a global standard makes that possible,” said Alex Gruzen, CEO of WiTricity. “With this progress toward standardization, carmakers and charging system providers can now accelerate their vehicle production programs with confidence.”

The convenience of wireless charging may prove to be a major factor that encourages mainstream drivers to buy electric cars. Car companies like Toyota, Audi, Nissan, and General Motors are busy bringing wireless charging capability to their production electric cars.

Source: Electric Cars Report

Steve Hanley

Closely following the transition from internal combustion to electricity. Whether it's cars, trucks, ships, or airplanes, sustainability is the key. Please follow me on Google + and Twitter.