Toyota has had a breakthrough in the quest to develop EV magnets with less costly rare earth metals.
The high costs and unsteady supply of rare earth metals needed for magnets in the motors of electric cars (EVs) pose a challenge for the automotive sector as carmakers race to ramp up EV production in the coming years. The extent of carmakers’ dependence on these materials became painfully clear in 2010 when China, a major supplier, imposed an export ban on neodymium, one of the rare earth metals used to make EV magnets. Periodic supply shortages have served as reminders.
Japanese carmaker Toyota recently announced the development of a new magnet which uses 20% less neodymium. It replaces the metal, which costs about $100 per kilogram, with the much more abundant lanthanum and cerium, each of which costs only about $5-$7 per kilogram.
“An increase in electric car production will raise the need for motors, which will result in higher demand for neodymium down the line”, said Akira Kato, general project manager at Toyota’s advanced R&D and engineering company. “If we continue to use neodymium at this pace we’ll eventually experience a supply shortage...so we wanted to come up with technology which would help conserve neodymium stocks.”
The magnets currently used in most cars to operate a wide range of motors use a total of about 30% of the rare earth elements neodymium, terbium and dysprosium. By increasing the amount of neodymium, carmakers such as Honda have found ways to eliminate terbium and dysprosium, which cost around $400 and $900 per kilogram, respectively.
What’s especially significant about Toyota’s new development is that, in addition to replacing a portion of the neodymium with lanthanum and cerium, it cuts out the most expensive metals. Kato did not provide details on the expected cost reductions for EV production but, Reuters reports, said that “Toyota could replace up to half of the neodymium used in magnets for motors which operate conventional vehicle functions like power windows with lanthanum and cerium, and around 20 percent for electric motor magnets.” Toyota aims to use the new magnets in EV motors within the next 10 years.
