Eliminating rare earths in EV motors

Several ways to avoid using rare earths in EV motors are outlined by IDTechEx.

That’s after releasing its report Electric Motors for Electric Vehicles 2024-2034, principal technology analyst Dr James Edmondson saying 82% of the electric car market in 2022 was using electric motors based on rare earth permanent magnets.

“China largely controls the supply of rare earths, and this has led to significant price volatility in previous years, with a large spike in 2011/2012 and a big rise between 2021-2022,” he explains. “Crucially, in comparison to some other technologies, several methods can be used to eliminate the use of rare earths in electric motors,” says Edmondson, adding these are outlined along with the pros, cons, and adoption.

He says the article is based on the new IDTechEx report that analyses different motor technologies for performance, materials, market adoption, and future potential.

“To briefly describe the construction of an electric motor, a stationary part (stator) has coils of metal (typically copper) fed by an electric current to generate a magnetic field. This field will then turn the rotating part of the motor (rotor). In a rare earth permanent magnet (PM) motor, the magnets are located on the rotor.”

Emondson’s report includes descriptions of the induction motor (or asynchronous motor), common earlier to the EV market and now used mainly as a secondary motor for acceleration boosts; the wound rotor motor (aka an externally excited synchronous motor or EESM), the switched reluctance motor (SRM) with significant efforts going into their development for EVs, alternative magnetic materials, and a high-speed ferrite motor with further optimisations.

IDTechEx predicts a significant rise in rare earth free motor technologies while expecting rare earth PM motors to remain dominant due to China’s EV market dominance and other mines coming online.

However, it anticipates that rare earth free options will account for nearly 30% of the market in 2034.