Western carmakers are trying to reduce their dependence on rare earth permanent magnets, a key driver of the electric car revolution.
It is reported that permanent magnet motors use rare earths such as neodymium and dysprosium, which naturally have magnetic force and are the core of many motors, providing power for the rotors of the transmission system.
Motors without permanent magnets, such as induction motors, use current (usually with copper wire) to generate a magnetic field and supply power to the motor. These motors are cheaper, but less efficient, and require larger batteries, thus reducing mileage.
Nissan said recently that it is abandoning the use of rare earth permanent magnets from its new Ariya SUV.
In 2012, Nissan developed a motor that reduced the amount of dysprosium needed by 40%, and expanded that reduction in 2016.
Tesla, the world's largest electric car maker, initially used induction motors without rare earth permanent magnets, but in 2017 it launched Model 3 with permanent magnet motors. In 2019, it redesigned the drive units of the Model S and X, using two motors, one with a permanent magnet and one without.
BMW's new iX3 SUV, to be launched this year, will be its first electric vehicle with a redesigned powertrain that no longer requires rare earths.
Renault is an alliance partner of Nissan and a pioneer of non-rare earth motors. The Zoe, a small city car launched in 2012, uses "wound" motors with copper wire.
Toyota has been reducing rare earths in its electric vehicles. The company said it was still working to achieve this goal after developing a permanent magnet with a 20 per cent reduction in neodymium consumption by 50 per cent in 2018.
Volkswagen is using permanent magnets that contain fewer two rare earths (terbium and dysprosium). In its all-drive electric models, the company also began to use permanent magnet motors on the rear axle and no permanent magnet motors on the front axle.
Daimler has reduced rare earths in its Mercedes-Benz electric cars and plans to eliminate the use of rare earths altogether in the medium term.
