Fast Company

Japanese Tech Could Allow Electric Vehicles To Drive Unlimited Distances

A road that charges electric cars has long been a pipe dream for combating range anxiety, but these Japanese scientists are making it work in real life.

It’s a well-known shortcoming of electric cars that they can only be driven short distances. The Chevy Volt, for example, has a maximum range of 50 miles on a single charge. And, while it’s possible to back up the electricity system with a fossil fuel-based one, as the Chevy does, that somewhat takes away from the point of having an electric car in the first place. 

It would be much better either if the car could go longer without needing to stop, or if it could somehow be recharged mid-flight, like a long-haul military plane.  And, in fact, the second possibility may not be as fanciful as you might think. 

Researchers at Toyota Central R&D Labs and Toyohashi University of Technology have come up with what they think is the world’s first mid-drive charging system, based on a similar mechanism that allows trains to travel under overhead wires. 

Under the still-experimental system, electrified metal plates are buried under roads, which “up-convert” energy via a radio frequency to a steel belt inside a car’s tires, as well as to a plate sitting above the tire. 

Although testing of the system has only involved low voltages so far, the researchers say the system could allow to electric cars to be far lighter than they are today. The electric cars would need smaller battery packs, as they would only need to to get and from the electrified highways. 

Anything to reduce the weight of today’s electric car batteries would be a good thing, potentially saving energy and conserving limited lithium supplies. The Chevy Volt’s battery assembly weighs a not-insubstantial 435 pounds, and measures 3.5& cubic feet.

There are obvious concerns about dangers to the public from stepping on an electrified metal strip, and some question the viability of digging up large stretches of road to install the infrastructure. But the idea does have precedents. Boston’s Logan Airport, for example, has ordered 60 “Online Electric Vehicles” that operate under a similar principle, and were developed by the Korea Advanced Institute of Science and Technology

[Image: Flickr user Mykl Roventine]

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4 Comments

  • daniel Spagnoli

    the problem with inductive charging (what this is) the efficiency on the very best systems is still only around 85%, so thats 15% of the electricity put in that is just going to waste(...do this to the entire roadway, and thats A LOT of wasted electricity), on top of the 8-10% that goes to waste already in the grid.

  • Jym Allyn

    Absolutely brilliant solution for recharging electric vehicles, but it likely will never happen until Halliburton gets the contract to construct the roadway power grid.

  • Alan Taylor

    How could billing be done?  The road-owner/authority would have to build these things, and supply them with electricity, and the users would use more or less energy depending on the vehicle, the payload, and driving habits.  So the users should be billed.  Can't use fuel tax.

  • Richard Bubb

    How about *seriously-large* amount of capacitors strung together to replace some of the weight of the batteries? Capacitors are lighter in weight (if memory serves), and can "download a charge" in seconds. Then they feed their stored power into the vehicle's drive unit, or it's slowly soaked-off into the battery-storage cells.
    Downside is that accidentally discharging the capacitors into oneself would be a not good thing.
    Charging could take place at stoplights. Just bury power transferring pads (mentioned in article above) at stoplight areas, so when cars are waiting, their capacitors are pulling in power. How to charge for this (pun optional) is not too difficult. The technology could be RFID-based, or Near Field Communications based. Data is transferred between car's computer and a central power & billing center.
    The problem of nearly unlimited range urban driving solved.
    The problem of long range road trips remains. Possible solution could be similar charging method as detailed above, but the charging "pads" would have to be every x miles. Automobiles (probably need a different description here: Rechmobiles, Re-chargeable mobiles sounds a little closer) queue into farthest  right lane, slowly drive over power pads, data auto exchanged for billing, gauge in car alerts driver when power is topped off.