Momentum Dynamics’ Wireless Charging Could Relegate Plugs To History

Of the perhaps 10 companies working on wireless magnetic inductive electric vehicle charging, Momentum Dynamics says its technology has a few advantages and chief among these is simply that “it works.”

The implication that it’s heads above all others is a bold one, but its CEO Andy Daga said it wasn’t the first to suggest the Malvern, Pa. based start-up is onto something special in delivering up-to 50-kilowatts or more reliably and efficiently.

Rather, back-handed compliments came from multi-billion dollar companies who – when informed several years ago Momentum Dynamics was transmitting 10 kilowatts – retorted that there’s no way it could be delivering so much power without defying laws of physics.

Patent by Nikola Tesla.

Patent by Nikola Tesla.

But indeed, Daga – and engineering VP Bruce Long who improved on concepts first patented by Nikola Tesla – have since heard apologetic concessions when they demonstrated 15 kilowatts and a large air gap for a system that’s now more potent and commercially viable.

“Clearly, we are well within the bounds of the physical laws,” said Daga, “but it has been the case that some generalists have approached this with overly conservative preconceptions of where the bounds exist.”

And really, Momentum Dynamics has only tweaked what others already are working with. Like most others, Momentum Dynamics’ system employs a pair of round coils – one on the ground attached to the grid, and another attached to the vehicle to charge the battery.

These create “donut” shaped waves of invisible magnetic fields. The difference is that Long found a way to “squash the donut” and make the system far more effective.

Rotating magnetic waves form a virtual donut shape.

Rotating magnetic waves form a virtual donut shape. In the near term, Momentum Dynamics is more focused on commercial and fleet markets, though its tech works just as well for passenger vehicles.

“More precisely,” said Daga, “we have learned how to ‘contain’ the field so that it does not interact with objects that are nearby, such as the metallic components and structures of a vehicle. This leads to higher efficiency at high power levels.”

Momentum Dynamics is also a bit unique in that it’s an eclectic team of outside-the-box thinkers. This now includes former Chevy Volt Line Director and Fisker CEO Tony Posawatz, who last December was named as chair of Momentum’s Technology Advisory Board.

Defining What ‘Works’

While today we hear of competing plug standards like SAE and CHAdeMO, and of plug-free charging on the horizon, no mainstream automaker has yet implemented wireless charging from the factory and there are reasons for this.

Actually the GM EV1, Chevy S-10 EV and the first RAV4 EV used a low-energy induction system, but the industry has gone to plugs, which so far have been able to deliver much more current, thus faster charging, with less energy loss.

Other wireless projects have been demonstrated, but they’ve had issues like heating the underside of vehicles when the juice is turned up, or they’ve been unable to reliably deliver much more than 3.3 kilowatts, though some have come up to about 10 kilowatts.

Momentum Dynamics approximately 90-percent efficiency is on par with 90-percent plugged level 2, and 86-87-percent plugged level 3. Losses for all types are at the power electronics. Despite reports saying wireless wastes energy, essentially, wireless efficiency is within range of wired.

Momentum Dynamics approximately 90-percent efficiency is on par with 90-percent-efficient plugged level 2, and 86-87-percent plugged level 3. Losses for all types are at the power electronics. Despite reports saying wireless wastes energy, essentially, this wireless’ efficiency is within range of wired.

That’s OK to recharge a Chevrolet Volt, but may fall short for the 6.6 kilowatts needed at the plug port by a Nissan Leaf, 10-20 kilowatts for a Tesla Model S, and these and other cars with DC quick-charge capability can accept far more power.

Thus most other wireless systems are not known to be ready to compete against high-power 240-volt, and 400-plus-volt plug-type chargers now and into the future.

“By the time inductive power charging becomes mainstream in the auto industry, the expectations for charging rate will be above 25 kilowatts,” said Daga. “As an example of this, J-1772 Combo, the newest iteration of the plug-in charging standard, will allow off-board DC charging to occur at up to 90 kilowatts. Momentum is charging at these levels (up to 50 kilowatts) today.”

Car20coil201

After more than four years development, patents, and pilot projects along the way, Momentum Dynamics has proven its technology doesn’t heat surrounding metal, and does the job as fast or faster than plug-in charging systems and for comparable cost.

Its up-to 50 kilowatts is delivered with 90-percent efficiency – on par with plug-type systems. And 50 kilowatts, said Long, is “not a ceiling,” but rather increases can be delivered if desired.

System demonstration under water.

System demonstration under water.

What’s more, it works in snow, ice, underwater, and can be embedded under pavement to foil would-be copper thieves and vandals.

Momentum Dynamics’ wireless technology conforms to international magnetic emission standards, poses no known risk to human or animal health, and actually, the human body is 40-times less visible to it than the best optical glass is to sunlight.

And then there’s the convenience factor of seamless, hands-free charging, though really that may not be what’s primarily driving things at this point.

Commercial Viability

While automakers like Toyota have said wireless charging is coming, and others like BMW may not be far behind, Daga said he expects consumer vehicles will be the last to fully adapt it as he focuses on commercial and industrial markets for now.

Since last year Momentum Dynamics has had a system working in the nearby town of Reading for Pennsylvania’s first major transportation authority to deploy all-electric vehicles, the Berks Area Regional Transportation Authority (BARTA).

BARTA20Buses

BARTA’s two all-electric Ford E-450 paratransit buses converted by Ohio’s Amp Electric Vehicles with 100-kilowatt-hour batteries have “been working without fault or incident since Aug. 7, 2013,” said Daga.

They are expected to travel up to 100 miles daily, and are one among other projects not being published due to non-disclosure agreements.

In a couple of months we may also hear of a major parcel delivery company using Momentum Dynamic’s system in New York City, and soon enough news may issue from makers of forklifts, utility carts, buses, and other commercial and industrial vehicles.

Aside from its ease-of-use, the compelling reasons commercial operators are likely to go for wireless charging include that their employees will have no plug-in procedure to remember, or trip hazard and legal liability to worry about.

“Our system is designed to fit easily into roadways and parking lots and be driven over by the heaviest vehicles,” said Daga of above-ground pads.

“Our system is designed to fit easily into roadways and parking lots and be driven over by the heaviest vehicles,” said Daga of above-ground pads.

There’s also that marvelous concept known as “opportunity charging.” This is where a waiting bus or taxi can passively recharge when it would otherwise just be killing time and burning fuel. Sitting atop an induction charger lets it instead add intraday range, and its battery can thus be engineered smaller to save weight, space, and most important of all, money.

Wireless charging therefore is being seen as making sense on a number of levels, aside from the needs of some consumers who find it less than convenient to have to plug in at night, and unplug in the morning – or repeat this during the day.

Demonstrations

Last week at Momentum’s offices, we were shown three systems – one for a Chevy Volt, another for a forklift, and another for an all-electric delivery truck with an 80-kilowatt-hour battery. This truck had a logo immediately recognizable to anyone on the planet, but we were asked not to publish photos due to a secrecy agreement yet in place.

First up was the Chevy Volt (lead photo up top), which is limited to 3.3 kilowatts not because Momentum can’t deliver more, but because GM won’t divulge data needed to up-rate the system.

An electric forklift with light panel that illuminates to show charging current.

An electric forklift with light panel that illuminates to show charging current.

The Volt can actually handle far more, but GM is “conservative” and so the bottleneck is in the car, not the wireless charging system.

The metal in the phone stayed cool. It also worked fine in a field where 11 kilowatts was being generated under the forklift.

The metal in the phone stayed cool. It also worked fine in a field where 11 kilowatts was being generated under the forklift.

Watching the demo was pretty uneventful – which is what you’d want in real life. The car drove over the pad, and an electronic ”handshake” was made. The charge light on the dash then came on and the car for all its system knew was plugged into the wall, except it wasn’t.

Next up came a forklift – an example of an industrial application – and here a bit of drama came not because of any problems, but to drive home the point, Daga and company have created a board of incandescent light bulbs. Here they turned the current to 11-kilowatts and the light intensity and heat made us start searching for sunscreen.

An electric parcel truck backs to a mockup loading dock/conveyor belt platform.

An electric parcel truck backs to a mockup loading dock/conveyor belt platform.

Lastly we walked over to another garage area to a parcel delivery truck – an example of a fleet application – which was parked proximal to a mocked up loading dock.

Just as simply, the truck backed over the pad – formed into a low-cut U-shape to minimize a trip hazard – and the software handshake took place, and the current was applied.

under_parcel_truck

This vehicle was fused to prevent more than 15-kilowatts, but the system could deliver 30 kilowatts, and as mentioned, Momentum Dynamics has at other times demonstrated 50 kilowatts.

With all these systems, the upper inductive coil attached to the vehicle must be at least within half the diameter of the lower coil.

So far basic systems to guide drivers to the bull’s eye have meant positioning is an easy operation. Technology also exists for parking and charging to be automated if desired.

What’s Next

To date Momentum Dynamics has not put out any fancy graphic-animated videos, and its Web site is deliberately nebulous with just enough info to hint of potential, but not many details are shared.

Speaking of “positioning,” the company is working with corporate clients and investors to sell its technology and unique team toward profitability.

Vice President of Engineering, Bruce Long (left), and Andy Daga, CEO, (kneeling).

Vice President of Engineering, Bruce Long (left), and Andy Daga, CEO, (kneeling).

It’s unique also in that it’s catering to several markets, not just buses or cars, but everything that can use wireless charging.

We don’t know when the first automaker will sign on with Momentum Dynamics but large clients in other industries have or are in process.

Meanwhile, Daga said the technology is ready, and foresees a future where except for a few Chevy Volts still running maybe 10 years or more from now, plugs could by then be largely a thing of the past.