Video: Rare earth-free electric motor = cheaper electric cars

Japanese researchers have created a revolutionary electric motor that doesn't require rare earth elements, a development that may drastically reduce the cost of electric vehicles.

The motor relies on switched reluctance technology, a form of magnetic resistance, to switch electricity on and off inside an electromagnetic wire coil that houses a steel rotor. The effect is rotary motion that turns at different speeds and with enough force to produce high levels of torque. Although the latest prototype produces a relatively low output of 50kW, researchers at the Tokyo University of Science are working to further refine and scale up the technology where it can offer the same kind of performance as motors currently on the market.

A commercial-ready rare earth-free motor would translate to more affordable EVs and hybrids since as much as 20 to 25 pounds of expensive rare earths goes into the manufacturing of the vehicle's motor and lithium-ion battery . Currently, China supplies 97 percent of the world's rare earth metals, a virtual monopoly that has enabled them to drive up costs simply by means of curbing exports.

However, one of the major challenges to getting the technology on the market is that switched reluctance motors are difficult to control. The researchers are hoping real-time computing that does a better job of handling the necessary complex algorithms can lead to a device that's more reliable and less prone to vibration and noise .

"There is a concern that noise and vibration might be problems when the motor is loaded into a vehicle," says Professor Nobukazu Hoshi in a Diginfo video interview. "So, I will experiment with control methods and new structures to reduce noise and vibration by conducting trial tests, as well as design and develop a motor drive circuit."

Learn more about the latest electric car breakthroughs:

This post was originally published on

Topics: Innovation


Contributing Editor Tuan C. Nguyen is a freelance science journalist based in New York City. He has written for the U.S. News and World Report, Fox News, MSNBC, ABC News, AOL, Yahoo! News and LiveScience. Formerly, he was reporter and producer for the technology section of He holds degrees from the University of California... Full Bio

zdnet_core.socialButton.googleLabel Contact Disclosure

Kick off your day with ZDNet's daily email newsletter. It's the freshest tech news and opinion, served hot. Get it.

Related Stories

The best of ZDNet, delivered

You have been successfully signed up. To sign up for more newsletters or to manage your account, visit the Newsletter Subscription Center.
Subscription failed.