A new report points to a surge in the demand for copper in electric vehicle (EV) motors as the industry shifts away from using rare earth elements.
Market research firm IDTechEx highlights this trend in its latest analysis, predicting a 4.8% compound annual growth rate (CAGR) in copper demand for the automotive market until 2034, driven by electrification and autonomy trends.
Magnet-free motor designs
This increase in demand aligns with major automotive players and suppliers adopting magnet-free motor designs.
The report, 'Copper Demand for Cars 2024-2034: Trends, Utilisation, Forecasts', offers an in-depth look at various automotive components impacting copper demand.
It examines traditional elements like wiring harnesses and auxiliary electric motors, as well as emerging technologies in electrification and autonomy.
IDTechEx research director Dr James Edmondson outlines in the report how electric motors, crucial for vehicle electrification, are undergoing a major transformation.
The automotive industry is transitioning away from rare earth elements in permanent magnets, due to their environmental impact and price volatility, which is in turn driving an increased demand for trusty old copper.
This shift, despite advances in winding efficiency and copper utilisation, will likely result in a 3.1-fold increase in copper demand for EV motors by 2034, compared to 2023.
IDTechEx's study identifies that alternative motor technologies, such as wound rotor motors, are becoming increasingly popular, leading to higher copper usage compared to permanent magnet motors.
By contrast, reluctance motors, which mainly use steel, could keep copper usage at levels similar to permanent magnet motors.
The research also highlights recent technological advancements in winding technology. The shift from round to hairpin-type windings improves copper utilisation.
Copper’s role
Motors are composed of two main parts: the stator, a stationary element, and the rotor, a rotating element.
Typically, the stator is made up of a steel stack wound with copper, generating an electromagnetic field. The rotor's composition varies with the motor's technology.
For instance, permanent magnet motors feature magnets in the rotor, while induction motors use copper or aluminium bars. Wound rotor motors are equipped with additional copper windings and reluctance motors primarily consist of steel.
Induction motors, once prevalent as drive motors, are now more commonly used in secondary applications. Their copper or aluminium rotors can lead to increased copper usage compared to motors with permanent magnets.
The wound rotor motor, an emerging magnet-free choice, significantly raises the copper content in motors, sometimes more than doubling the copper found in a comparable permanent magnet motor.
Alternative technologies might maintain copper use at levels akin to permanent magnet motors. For example, the reluctance motor, with its predominantly steel rotor, doesn't add copper or aluminium.
Despite this, reluctance motors face challenges in power density, noise and efficiency. Ongoing improvements are being made but mass production in electric cars is still pending.
The axial flux motor, a newer development, shows high power density and, consequently, a lower copper demand relative to its power output.
Innovations by companies like Schaeffler, Lucid and BorgWarner (NYSE:BWA) are further optimising copper use in motor performance.
Despite considering aluminium as a potential replacement for copper in stator windings, the report anticipates copper to remain the primary material due to its superior performance.