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Mitsubishi Motors to introduce sporty concept version of Outlander PHEV

Wireless charging company WiTricity scaling up EV charging capability as well as itself

WiTricity, the MIT spin-off commercializing strongly coupled magnetic resonance wireless charging technology for EVs as well as consumer devices, industrial, medical and military applications (earlier post), has work underway to deliver wireless charging systems capable of delivering 10s of kilowatts for plug-ins, compared to the current 3.3 or 6.6 kW, says CEO Alex Gruzen.

In addition to its ongoing work on the technology, WiTricity has been steadily tuning its executive suite over the past few months, starting with the naming of Gruzen as CEO in April. Gruzen succeeded Eric Giler who, in his five-plus year term as CEO, successfully established WiTricity’s business foundation and commercial capabilities. Giler remains a member of the WiTricity Board of Directors. Gruzen earlier served in senior management roles at Dell, HP, Compaq and Sony.

Subsequently, WiTricity hired Farooq Butt, who served most recently as VP of Worldwide Business Development and Strategy for Dell’s End User Solutions group, as Senior Vice President of Business Development and Strategy; and just last week added Donald R. Peck as Chief Financial Officer (CFO), who most recently served as EVP, CFO and Treasurer of Lojack Corporation.

The executive suite changes occur as WiTricity continues to land more funding ($25 million last year, earlier post), and to expand further its key partnerships, which, in the automotive space, now include Delphi (earlier post); Toyota (earlier post); IHI and Mitsubishi Motors (earlier post); and TDK (earlier post).

The WiTricity power source, left, is connected to AC power. The blue lines represent the magnetic near field induced by the power source. The yellow lines represent the flow of energy from the source to the WiTicity capture coil, which is shown powering a light bulb. Note that this diagram also shows how the magnetic field (blue lines) can wrap around a conductive obstacle between the power source and the capture device. Source: WiTricity. Click to enlarge.

WiTricity’s technology is based on sharply resonant strong coupling, and is able to transfer power efficiently even when the distances between the power source and capture device are several times the size of the devices themselves.

WiTricity’s technology is a non-radiative mode of energy transfer, relying instead on the magnetic near field. WiTricity proprietary source and device units are specially designed magnetic resonators that efficiently transfer power over large distances via the magnetic near-field. The magnetic field can wrap around a conductive obstacle between the power source and the capture device.

The power transfer efficiency of a WiTricity solution depends on the relative sizes of the power source and capture devices, and on the distance between the devices. Maximum efficiency is achieved when the devices are relatively close to one another, and can exceed 95%.

One of the things WiTricity has been doing since the first public disclosure back in 2005 and then the formal formation in 2007 is taking this core of technology of magnetic resonance and applying it into practice. We started out with big 3-foot wide cooper coils. From 2005 to today, we’ve come a long way. There are tailored solutions that can move milliwatts at very low cost—compact and inexpensive to implement— all the way to throwing kilowatts into EVs.

In addition to the 3.3 kW system [the power level of charging EVs] we also have a 6.6 kW solution. And we have work underway to to go to 10s of kilowatts. It’s a broadly applicable technology. As the cost [of batteries] comes down, and the size grows, right in parallel, we are going to higher and higher power transfer. We just march in lock step with industry development.

—Alex Gruzen

Gruzen suggests that widespread wireless charging—including interoperable public infrastructure—is particularly interesting for plug-in hybrids.

The convenience is extraordinary. In many of these vehicles, the battery is relatively smaller. At every point today with a plug-in hybrid, you are presented with a choice of when I pull in to the garage, do I plug in now or not plug in now. When the batteries are smaller [as in plug-in hybrids], you are not getting all the fuel economy benefit if the battery is not fully charged. The relative value for the plug-in hybrid is the easy topping off of the battery. I feel like there is [potentially] a real catalyst for dramatically improving the core user experience.

—Alex Gruzen

WiT-3300 components. Click to enlarge.

WiT-3300 Development Kit. For plug-in vehicle applications, WiTricity currently is offering to its partners the WiT-3300 Development Kit—a wireless “park-and-charge” system that provides efficient wireless energy transfer.

The WiT-3300 system is designed to charge at the same 3.3kW charge rate as many wired chargers and at efficiencies up to 90%. The WiT-3300 supports charging with ground clearances ranging from 10-20 cm, and custom configurations can be provided for vehicles having higher or lower clearances. Wireless energy transfer can occur through any non-metallic material, which means that the source device can be installed beneath a garage floor or paved parking space.

With the WiT-3300, energy transfer system does not require the source and capture resonator pairs to be perfectly aligned in order to achieve efficient energy transfer. In addition, the strongly coupled magnetic resonance energy transfer provides products which are 4x smaller, 2x lighter, and more efficient than solutions based on traditional magnetic induction.

Available as options for the WiT-3300 Development Kit, the WiTricity WiT-3300 Foreign Object Detection (FOD) and WiT-3300 Live Object Detection (LOD) systems help ensure the safe operation of WiT-3300 electric vehicle (EV) charging systems.

  • FOD System: Built directly into the WiT-3300 R2.3 source resonator enclosure, the WiTricity FOD system senses the presence of metallic foreign objects and debris that could be affected during charging, and enables the intelligent shutdown of the charging system before these objects can be heated by the system’s magnetic field.

  • LOD System: Built as a perimeter sensor for the WiT-3300 source resonator, the WiTricity LOD sensor senses the presence of humans or animals that intrude into a detection zone around the source, and enables the automatic shutdown of the charging system.



10s of Kw could mean as much as 200Kw?


Why would it?


At some point, the cost, efficiency and durability of the high-power schemes need to be compared to technologies like Busbaar and Siemens' electric highway.

It's an interesting dilemma. I understand the desire to provide an effortless user experience, but until 50+kW (perhaps 100+kW?) wireless chargers are available, cars will need both pads and plugs. Considering the high bar set by Tesla, it seems that providing long distance wireless refueling will be a steep hill to climb.

How much of a premium will customers pay? A sample of one, our household's Fiat 500e driver, (the only one who infrequently forgets to plug in overnight) offered a $10 month premium.


Plugless charging transforms the prospects for opportunity charging of PHEVs, not to mention making charging possible at all without impossible amounts of street furniture anywhere which is NOT middle America or rural.

Although I appreciate the pun, I don't see what is transformative about wireless for PHEVs. Convenient, to be sure. But one thing wireless can't do is share one 25' cord with 4-6 parking spots. It also likely requires automakers to standardize on the placement of the car mounted receiver. Considering their inability to agree even on a coupler, that seems like a hurdle.

If a city can widely deploy parking meters that earn $0.25 per hour, surely they can figure out how to charge me... $0.25 per kWh. x3, x6, x50 per hour.


Sure you could have one cord for several charge spots if you needed to by having the charge pad on the end of it.

I still have not found out from you where you figure that charge post are going to go in most cities in the world.

I invite you again to go to Wick Road in Bristol and have a look in street view and tell me where on earth they would go unless buried under the street.

That is far more typical of most cities in the world than the broad clear streets of middle America.

If battery electric cars are to be anything like a universal solution then plugging in alone won't do.

Of course one alternative would be to use fuel cells, but then you don't fancy that either.


Added convenience may become the key factor for wireless electrified vehicles e-charging as it did with automatic transmissions, e-starters, future automated driving etc etc.

Another important advantage of wireless EV charging would be to get rid of visible cables and plugs similar to current underground cables, smart phones, tablets and wireless TVs etc.

Americans and Canadians used to XXX 1000s of power cables, TV cables poles etc may not see the advantage of clean wireless EV charging.


Wireless complicates the charging problem as well, requiring the authorization system to be built into the vehicle instead of being just an RFID card (like ChargePoint) or just an electric outlet.

Wick road in Bristol isn't the world, either.  I already spelled out an option for the Wick roads, at least for 10% plug-in penetration:  mount overhead arms on the street light poles (possibly retractable) and hang cords from those.  If one space out of every 3-4 has charging available, that will do for years.  When the road is repaved it'll be time to update the infrastructure.


Wick Road is a lot more like most urban areas in the world than typical roads in US suburbs are.

I also replied to your notion that overhead wires would do the job.

If you have a look at the street views you will see that there are zero overhead electricity cables.

And there are zero chances of them being authorised.

If you are looking for anything remotely like a universal solution instead of one for that small fraction of cars which are garaged, plugging them in won't work.

It doesn't bother me as I have a fall back solution of fuel cell vehicles.

You don't want that, so the solution you proffer has to have very wide applicability.


Meh... if the pols and public don't want what engineering can provide, they can do without.

I suspect attitudes will change after the first few engineer/artist collaborations.  Make something that's both functional and pretty, and everyone will want it.  Besides, it's only (and explicitly) a stopgap; it would be removed after the next major overhaul.  The FCEV has no upgrade path that gets around its flaws.


Precisely the opposite of what happens.
If engineering solutions don't conform to what society allows, they don't happen.

It also substitutes a weather dependent intrusive solution for a vandal proof weather resistant, unobtrusive one.

In many countries electricity outages are way less frequent than in the US, precisely because cables are buried.

FCEVs have loads of upgrade paths.
If you ignore them that hardly means they don't exist.


USA has as love affair with poles and overhead cables and things. Chicago even has overhead subways??? The idea may be to protection pedestrian from sunburns etc.

Wireless EV charging will win because it is more convenient and it does get rid of visible cables.

We also live in an area where all cables are buried and we would not like charging cables around.

If engineering solutions don't conform to what society allows, they don't happen.

Before WWII, British society didn't want big bags of town gas on tops of cars and buses.  But during the war, lots of things ran on town gas; society changed to accept the engineering reality.  Society preferred imperfect solutions to doing without.

Putting inductive charging systems on Wick road and all the rest requires a major infrastructure update.  On the other hand, there's already foundations and wiring for the pole-mounted street lights.  The wiring is under-utilized, being used only a few hours a day.  This has the makings of a fast, cheap, partial solution; perfection can come later.

It also substitutes a weather dependent intrusive solution for a vandal proof weather resistant, unobtrusive one.

Existing chargers aren't particularly weather-dependent.  I don't see why you think a stopgap system would be any worse off.

FCEVs have loads of upgrade paths.

You're still stuck with the chemistry of hydrogen, and the inherent advantage it hands to coal and natural gas as the ultimate energy source.  Most nations burn coal today because they refuse to take on the expense of cleaner fuels, and hang the climactic consequences; if you go with hydrogen, you extend that excuse for at least another half century.  I don't think this is something we dare to risk.



Roads get resurfaced regularly, and electric cars are not going to be a universal solution anytime soon.

Areas where overhead electric cables aren't used are not going to change that, and any realistic proposal has to accept that.

I am not going to divert into discussion of electric cars, which I only brought up because clearly not only am I proposing a charging system for batteries which could really be installed whilst you are sticking by one which has zero chance, but there are realistic alternatives in fuel cells, which you also refuse to accept.

So you are advocating a system which has no chance of happening at all, and ignoring even the possibility of anything which actually could happen.

Seeing that we live in a world where Cadillac finds a market for a power-assisted actuator to open and close the cover on the center console cup holder, I do not dismiss the market for wireless charging.

It appears we're still a few years away from the standards being finalized. From the Toyota video above, even the issue of whether the receiver is located in the front or the back of the car has not been settled.



"..ignoring even the possibility of anything which actually could happen.."

I agree, I like to go with ideas that might actually work and be USED. If an idea does not get wide spread use, it can do little good.


I'm sure I could design something that looked cool enough that people would say "Hey, that looks neat!  I want to use/see more of those!"  Not that I'm much of an artist, but imagine if you will something that bends over the sidewalk like a fishing pole with a big one on the line, with the line going vertically down to the "hook" which is the plug going into the car.  It would be well above head-level and retract back to vertical when not in use.  With some of the composites and actuators available these days you could probably make one with no gears, shafts or bearings.

Patrick Free

For me the future proof long term optimal power for residential, hotel, and work place chargers (where people typically stay hooked 7H - 8H each time during night sleep or day work) is 22KW, as already used in Germany for wired chargers. Wired or wireless should not make a difference here.
Long term all people want to get the nirvana 500M battery for their EVs, that I estimate requiring # 160KWH. So it will come..., likely from Tesla 1st, and chargers planning should take that into account. And to full charge 160 KWH on 22KW charger you only need 7.3H that is perfect for a night or a work day charge (or <6h for 80% charge, even better).
By the time that Nirvana 500M battery comes such 22KW chargers can charge today Tesla 85KWH battery in <4H full, or in # 3H at 80%... leaving to the local grid (if it's capable to do that) the possibility to reverse use of that EV battery during the rest of the night or work day time, especially to help them pass peak demand time, the major one being in the evening. You could return home # 8pm with 30% charge left in your battery, plug the car to the grid letting the grid know you only need the car fully charged # 6am. Then grid instead of charging it in the evening peak times, it could pull the 30% charge left in it during that time up to a maximum discharge rate, then stop, and when the peak time is over, start recharging it to get to the full charge expected in any case before 6am....
Then for my dream 30KWH PHEV SUV (that yet no German car vendor wants to build for me...but I'll wait holding my 60K€ budget and extending my beloved BMW 530DA till one accepts to build a good one for me, with a powerfull all electric mode) then that 22KW could 80% charge it in # 1H (Call it a fast charger !), and current smaller pure EVs 24KWH could fully charge in # 1H too...etc.
Hence why this 22KW should be the optimal standard for me.


Aerial and visible cables and clothes lines are rightfully banned in many areas and places. That's our case.

Wireless underground charging facilities will quickly become the standard in all those areas and places?



Yes, a 22 KW charger operation on 3-phase 440 VAC or 660 VAC could do the job in most places with decent size cabling.

Hotels-Motels and other equivalent places with multiple charging places may require an added main transformer.


When we get the 160 kWh EV at even 5% of sales, that 22 kW charger will start making sense.  I suppose that if we're going to bury conduit and pull wires today, it makes sense to size them to be able to handle such demand without doing any more digging.

That day won't come for some time.  Right now we've got just enough battery manufacturing capacity to make HEVs and some PHEVs.  PHEVs charge at 3.3 kW or less, and if we retrofitted HEVs to top off their traction batteries from grid power between trips they'd probably fill up in 30 minutes on 1 kW or less.  That is what we should be gearing up to support right now, because that is where we have the most leverage against petroleum consumption today and in the near future.


An EU manufacturer is already offering 640 KW chargers for e-trucks and e-buses and other large EVs with larger (300+ kWh?) battery packs.

That being said, future extended range e-cars and e-pick-ups with 160+ kWh battery packs will probably need 200 kW to 300 kW chargers for fast recharges.

Others, short and mid-range EVs, could survive with 22 KW charging facilities as a bare minimum.

By the way, changing underground electric cables (normally installed in large conduits) does not mean more digging. Old cables and/or pre-installed pulling cables are used to pull new cables in.

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