Wireless EV Charging Is Coming: Here’s How It Works

A nationwide electric vehicle charging network is still in the works, but some automakers are experimenting with what could be the next big thing: wireless EV charging.

The Society of Automotive Engineers (SAE) published official standards in 2020, and automakers are now quietly testing and prototyping. While it’s hard to say exactly what will be available and when, there’s a good chance it’ll be modeled off technology from Massachusetts-based WiTricity, which licensed its intellectual property to Wiferon, the German wireless EV charging supplier that Tesla acquired in July 2023.

“The whole industry is like, ‘OK, Tesla bought a wireless charging company. It’s coming,'” says Nathan Yang, chief product officer at FLO EV Charging. “A bunch of other companies are prototyping, too—BMW, [Volvo parent company] Geely, Hyundai/Genesis, others.”

Research firms are also chasing wireless solutions, with a recent breakthrough coming out of Oak Ridge National Lab.

PCMag got an up-close look at WiTricity’s technology at last year’s Move America conference, and what we saw paints a rosier future for EVs—one where drivers won’t need to wrangle thick, stiff cords, and the landscape isn’t dotted with as many unsightly stations.

What Is Wireless EV Charging?

Rendering of WiTricity wireless charging equipment (Credit: WiTricity)

WiTricity’s product is an alternative to the standard level 2 chargers commonly used in homes and public parking lots. It hooks up to a local power supply, as shown above in a familiar-looking wall box. However, it does not have to be on the wall.

“You could hide it in a planter,” says Amy Barzdukas, chief marketing officer for WiTricity. Without a cord coming out of the box, drivers have no reason to interact with it regularly. As a result, “there’s a lot less visual pollution” than the stations most people expect to pop up in their communities as the shift to EVs progresses.

A conduit runs from the power box onto the floor and into a charging pad. When the vehicle parks over the pad, charging initiates. In the future, these pads could be embedded in city streets, public parking lots, at home, and at work, so drivers can charge as they go throughout the day.

“I call this power snacking,” WiTricity CEO Alex Gruzen sai d on an informational webinar in April.

WiTricity wireless charging equipment at MOVE America 2023. (Credit: Emily Dreibelbis)

At the conference, WiTricity demoed a retrofitted Ford Mustang Mach-E, to which it had added a third dash screen. A test driver parked over the charging pad and pressed “initiate charge” on that screen. Then, the Ford-built screen behind the wheel showed the vehicle was charging.

A modified Ford Mustang Mach-E charges wirelessly, as shown on a third screen that WiTricity retrofitted for the prototype. (Credit: Emily Dreibelbis)

On a consumer-ready EV, that extra test screen would not be there. Instead, the software would be baked into the vehicle’s main dash screens.

“When we do an integration with the OEM, it would automatically trigger the front-facing camera and would tell you when you’re appropriately parked over the target area,” says Eric Barber, senior director of vehicle integration engineering at WiTricity. “Then, all you do is put the vehicle in park, and then it would automatically happen.”

How It Works: Magnetic Resonance

Energy flows from the pad to the vehicle through a magnetic field, or between two “magnetically coupled resonating coils,” according to IEEE. That enables a wireless power transfer (WTP) between the pad on the ground and a receiver inside the vehicle.

“This receiver goes in the car and puts DC energy directly into the battery. It sits over the on-board charger,” says Barzdukas. EV makers would need to install this receiver inside their cars as a prerequisite for the driver to charge wirelessly. For those who currently own an EV, that unfortunately means they won’t be able to charge it wirelessly without a serious retrofit.

Amy Barzdukas, WiTricity CMO, poses with a wireless charging receiver that would be built into the vehicle. (Credit: Emily Dreibelbis)

“You can drive over [the pad], or walk over it, or your cat can walk over it safely even if it’s charging,” says Barzdukas. Wireless chargers operate “far below the radio frequencies which are present all around us,” according to one study by IDTechEx, and can “pass through these objects and the human body without any interaction or causing any harm whatsoever.”

One of WiTricity’s biggest challenges is fighting the misconception that wireless charging is less efficient than corded. “People say, oh if I charge my phone wirelessly it takes longer, but that’s not the case here,” she says. “So, we are constantly educating people that they don’t have to make a compromise when they go wireless.”

(Credit: WiTricity.com)

Another difference with wireless cell phone charging: the vehicle’s placement over the pad does not need to be as precise, as the power can transfer over a relatively large area. “The difference with what we’ve pioneered here is the positional freedom,” Barzdukas says. “You don’t want to have to park in the exact right spot, and you want one charger in the ground that works for a sports car, a sedan, or SUV.”

So far, parking position has not been an issue in WiTricity’s testing. “We’ve done events where 100 people drive the car, and over 90 get it in the right spot on the first attempt,” says Barber.

A Pricey New Configuration, at Least to Start

When wireless charging products hit stores, they’re likely to be a premium product, at least to start. “The price will come down over time,” Barzdukas says. “We’ve done a ton of consumer research, and they’ve told us they would cheerfully pay thousands for this.”

She’s probably right: Other studies have found that consumers are willing to shell out some serious cash for higher-performing batteries. Wireless charging could be another upgrade that appeals to deep-pocketed drivers.

Since car companies would need to build WiTricity’s hardware into their vehicles to support wireless charging, FLO EV Charging’s Yang predicts EV buyers will add it as an optional upgrade when configuring their vehicles, along with other enhancements such as self-driving features and bigger battery packs.

The Future of Wireless EV Charging

Commercial fleets are currently piloting WiTricity’s charging solutions, acting as a “testing ground” before releasing them to passenger cars, says Barzdukas. At CES 2024, WiTricity announced its next move: wireless pads for low-speed vehicles, such as golf carts, going on sale in summer 2024.

The company is also exploring vehicle-to-grid wireless charging. “We’re already starting to test that with a few global automakers,” says Pamposh Zutshi, senior director of product management. “It opens up a whole new opportunity for the grid and to create value for the car owner.”

Neither Barzdukas nor Zutshi would reveal the full slate of partners they’re working with on V2G or any other products, except to say: “You’ve heard of them.”

“Things take a long time to test in the auto industry but we are at the tail end of all that,” says Barzdukas. “The standard was a big open door, and now that we’ve gotten to the level of maturity where people can see it’s charging and it’s working, the roof is going up.”