The EV Market Doubles Down on Permanent Magnets Despite Material Costs

With the continued global turmoil experienced over the past few years, the prices of almost everything are rising. This has been especially true for the rare earth materials used in the manufacturing of electric motors for electric vehicles (EVs). The price of neodymium has remained fairly constant from 2013-2020, but 2022 saw a very sharp rise to its peak in February at 3.8 times greater than the previous average. While the price has settled somewhat, in October 2022, it is still 2.4 times higher than it was between 2013-2020. While some automakers have alternative motor technologies that don't rely on rare earths, the market has not shifted in this direction significantly; why is that the case?

What Are the Motor Technology Options?

IDTechEx has carried out extensive research into the electric motor market for electric vehicles, including analysis, benchmarking, and demand forecasts of different motor technologies in its report: " Electric Motors for Electric Vehicles 2022-2032 ". To date, the three main categories used in the electric car market are permanent magnet motors, induction motors, and wound rotor motors. From a materials point of view, each of these typically uses a stationary stator with copper windings; the difference is in the rotor construction. Permanent magnet motors, as the name suggests, use magnets on the rotor that are typically made using rare earths, with neodymium taking the largest fraction (although there has been some progress in ferrite-based magnets). Induction motors use a copper cage or windings on the rotor and use an asynchronous operating principle. Finally, wound rotor motors also have copper windings on the rotor, but these are excited directly with an electric current.

There are certainly other motor technologies, such as switched reluctance motors, and developments have been happening to make these more suited to passenger vehicle applications, but the market to date has been dominated by the three options above.

What Is Happening in the EV Market?

Permanent magnet motors are by far the most commonly used electric motor in the EV market thanks to their high power density , torque density, and efficiency. In 2021, permanent magnet motors made up 84% of the electric car market. Despite their use in earlier Tesla vehicles, induction motors have been largely relegated to the secondary drive motor thanks to minimal drag losses while not in use. Wound rotor motors are the typical choice when a permanent magnet-free primary drive motor is required. Wound rotor options have been used by Renault and recently adopted by BMW for its 5-generation drive.

With the rising costs of materials, especially expensive rare earths, interest has been seen towards eliminating their use in electric motors; as previously mentioned, BMW and Renault have made use of wound rotor motors, and Mercedes went with induction motors for its EQC model. Established motor suppliers like MAHLE and smaller companies like Advanced Electric Machines are also focusing on magnet-free alternatives. Despite the interest, the permanent magnet motor market share for the first half of 2022 actually rose to 86% over 84% in 2021.