Tesla’s claim of rare-earth-free drive trains has sector reeling

Colin Campbell, director of drive-train engineering at Tesla, dropped quite the bombshell at Tesla’s investor day on 1 March. “We’ve designed our next drive unit, which uses a permanent-magnet motor, to not use any rare-earth elements at all,” he announced. Tesla had previously reported a 25 percent reduction of rare-earth content in Model 3 and Model Y drive trains. Further trimmings were expected, but few would have thought it possible that a rare-earth-free permanent-magnet motor was close to commercial application.

Tesla’s earliest models used an induction motor, in which the magnetic force that causes the rotor to turn is generated by an alternating current. The Model 3, introduced in 2017, adopted motors in which strong permanent magnets are used to generate the magnetic field. Permanent-magnet (PM) motors offer greater efficiency and power density. In 2022, over 80 percent of the electric vehicle motor market was accounted for by PM motors, according to research by IDTechex.