WiTricity and Wireless Charging for Electric Vehicles

Seems like wireless charging ought to be a thing by now, at least for smartphones. If someone sold a $100 device that would automatically charge your phone within “Wi-Fi distance,” we’d probably all have one in our homes. Is it a big conspiracy by the phone companies so they can continue selling us over-priced charging cables? Who knows, but there are, certainly, companies working on the problem. We looked at some of them in a piece titled “Wireless Charging Ready to Spark Mobile Revolution.” One of the companies in that list, WiTricity, thinks the most lucrative use case for wireless charging technology is electric vehicles (EVs).

About WiTricity

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Founded in 2007, WiTricity has taken in around $36 million in funding so far from names like Intel and Foxconn, one of the world’s largest consumer electronics manufacturers. The company’s magnetic resonance technology enables power transfer wirelessly from grid to battery as efficiently as a conventional plug-in and at the same speed. Power can be transferred through asphalt, cement, snow, or ice, and even bidirectionally which means your electric vehicle’s batteries could be used to power your home when energy from the electric grid is most expensive.

Update 10/30/2020: WiTricity has raised $34 million in funding to continue its leading-edge wireless power platform development and capitalize on the commercial momentum for wireless charging for electric vehicles (EVs). This brings the company’s total funding to $70 million to date.   

All the advantages of using magnetic resonance for wireless charging
Credit: WiTricity

WiTricity’s technology is protected by over 900 global patents including key patents licensed exclusively from MIT. Just last February, Qualcomm took a minority stake in the company after selling them a technology platform and IP assets which was previously being marketed as “Qualcomm Halo wireless electric vehicle charging.” Magnetic resonance seems to check all the boxes, and WiTricity seems to have built a deep moat of intellectual property. The question is, does wireless power transfer make sense for electric cars?


We’ve written a number of pieces on electric vehicle charging companies, noting that ChargePoint seems to be in the lead with The World’s Largest Electric Vehicle Charging Network. Still, we don’t know what the optimal charging network should look like. Electrify America claims to have the quickest chargers – in other words, the most powerful – but the bottleneck is the electric vehicle batteries which need to support these powerful chargers. In the case of Tesla, they own both the chargers and the electric vehicles which lets them improve their charging capabilities quickly. 

Tesla is reducing time-to-charge with V3 supercharging
Credit: Tesla

Increasing range and decreasing time-to-charge are understandably two very important metrics driving electric vehicle adoption, but the latter may not be as important as you think.

Wireless Charging for Electric Vehicles

In our previous piece on Investing in Public Electric Vehicle Charging Networks, we talked about three types of wireless charging stations being deployed for electric vehicles.

  • Level 1 Chargers – equate to plugging your car into the wall socket to provide overnight charging, typically what EV owners use at home
  • Level 2 Chargers – uses double the standard voltage and delivers 10-60 miles of range per hour of charging
  • DC Fast Chargers (Level 3 and up) – offers 60-100 miles of charge in just 20 minutes.

DC Fast Charging (DCFC) outlets will be located at places like gas stations, rest areas, and shopping centers to help extend range for longer distances. However, according to studies by the National Renewable Energy Laboratory, DCFC outlets will only be needed 4% of the time, when EVs are used for long trips that extend beyond their battery capacity. The other 96% of the time, DCFC chargers will be overkill.

A WiTricity white paper makes the case for wireless charging by comparing the DCFC experience to the traditional gas station. There are an estimated 168,000 gas stations in ‘Murica that sell fuel to drivers, and you rarely need to queue. If each gas station has an average of 6 pumps, that’s about 1 million gas pumps needed to service drivers so they don’t need to queue. If all vehicles were electric, we could estimate a need for 1 million charging stations to satisfy EV drivers. The problem is, filling your gas tank is much quicker than charging a battery. Because gasoline is so energy dense, filling your tank with a gas pump is the equivalent of charging an electric vehicle at a rate of over 3 megawatts (about 12x more powerful than Tesla’s latest 250kw V3 supercharger). This means that even using a DCFC charger, EV drivers will need to wait 30 minutes to charge their cars compared to 3 minutes for a gas-powered vehicle.

When you consider that 95% of the time cars are simply parked doing nothing, wireless charging makes even more sense. According to studies by the U.S. National Renewable Energy Laboratory, 80% of EV charging will take place at home. Being able to pull into your garage and not worry about charging your car is a huge value add for EV owners.

The WiTricity DRIVE wireless charging solution for electric vehicles
Credit: WiTricity

The wireless charging station seen above called WiTricity DRIVE delivers the following benefits:

  • Scalable charging rates of from 3.6 to 11 kW, to meet the needs of vehicles ranging from small battery packs to large
  • The ability to charge vehicles ranging from low ground clearance sports cars to high ground clearance SUV’s
  • The ability to be installed as an on-ground charging pad in a private residence or buried in the pavement of a parking lot as public charging infrastructure.

Why not make charging your car as simple as parking it?

Progress Being Made

Any EV driver would agree that wireless charging is easier and more convenient than plugging in during pouring down rain. We can also see how this method of charging would almost be imperative for autonomous vehicles. But it’s not that simple. Automakers need to agree that this is the way forward, standards need to be put in place for a one-size-fits-all charging pad, and urban planners need to incorporate these charging pads into new parking lots. So, what progress has been made so far?

In order for wireless charging to become commonplace, automakers need to collaborate on a common standard for wireless charging. Some of the disclosed automakers WiTricity is currently working with include Honda, Nissan, GM, Toyota, and Hyundai (they’re also working with Volvo on solutions for construction equipment). However, magnetic resonance isn’t the only game in town.

Inductive Wireless Charging

In 2018, we saw the introduction of the world’s first vehicle that is factory equipped with wireless charging, the BMW 530e iPerformance sedan. That charging system is based on a different method of wireless charging referred to as “inductive charging.” An article by Car and Driver talks about how inductive charging has been lagging stating:

We might have expected to see wider availability of the technology, but it has been hindered by its high cost, concerns about interoperability, and relatively slow charging times. That’s too bad given the convenience that the technology promises. 

One problem with inductive charging is that it “requires the transmitter and receiver to be in close contact and with perfect spatial alignment.” It is also less efficient, with a claimed efficiency rate of around 85% which means it charges at a “similar speed” to the typical BMW wall charger. These aren’t showstoppers, but if we’re going to decide on a technology to standardize, let’s choose the most optimal one.

From Evatran to Tesla

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Another company that had a go at wireless charging using inductive charging was Evatran. Founded in 2009 under the brand “Plugless,” the founder and CEO Rebecca Hough “helped raise $2.5 million from private investors and $4 million in Department of Energy grants, and recruited partners such as Google, Hertz, Duke Energy, and Bosch to test and give feedback on Evatran’s product.” That’s according to a May 2013 article by Inc in which Ms. Hough predicted great things for the company saying they were “working with major U.S. and German auto manufacturers on an OEM integrated product that should hit the market in 2015.”

Fast forward to today and Evatran was looking to be acquired in full by an existing investor, a China-based auto parts maker, who owned around 16% of the company and wanted to purchase the remainder for $10.5 million. When the deal fell through due to regulatory reasons, Ms. Hough moved over to Tesla in March of 2018 starting as a Senior Product Manager tasked with developing machine vision products. Since then, she transitioned through a number of different roles, finally settling on the role of “Senior Manager – Supercharging.” Could it be that Tesla is preparing to roll out wireless charging soon? We already know that Tesla’s “Battery Day,” an event that’s expected to take place in May, will include some news relating to their investment in ultracapacitors. It’s something we touched on in our piece on “Skeleton Technologies and the Future of Ultracapacitors.” We’ll just have to wait and see.


Both Tesla and ChargePoint are focused on building out networks of fixed charging points, but there are other configurations to consider. At least one company is working on mobile charging. FreeWire Technologies recently took in $25 million from BP and ABB to develop charging units that can move around parking lots autonomously. Another startup called ampUp just raised funding from Hyundai to build a P2P electric vehicle charging network where everyone shares their chargers to increase availability and usage.

Then, there’s wireless charging, which could be built into roadways and parking spots to make charging completely seamless. Even if wireless electric vehicle charging doesn’t take off, WiTricity’s strong IP portfolio will allow them to easily pivot into other uses cases for wireless power transfer. For now, they seem to think charging electric vehicles is the way forward for wireless electricity.


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