A Survey on the Sustainability of Traditional and Emerging Materials for Next-Generation EV Motors

The transportation sector is experiencing a profound shift, driven by the urgent need to reduce greenhouse gas (GHG) emissions from internal combustion engine vehicles (ICEVs). As electric vehicle (EV) adoption accelerates, the sustainability of the materials used in their production, particularly in electric motors, is becoming a critical focus. This paper examines the sustainability of both traditional and emerging materials used in EV traction motors, with an emphasis on permanent magnet synchronous motors (PMSMs), which remain the dominant technology in the industry. Key challenges include the environmental and supply-chain concerns associated with rare earth elements (REEs) used in permanent magnets, as well as the sustainability of copper windings. Automakers are exploring alternatives such as REE-free permanent magnets, soft magnetic composites (SMCs) for reduced losses in the core, and carbon nanotube (CNT) windings for superior electrical, thermal, and mechanical properties. The topic of materials for EV traction motors is discussed in the literature; however, the focus on environmental, social, and economic sustainability is often lacking. This paper fills the gap by connecting the technological aspects with sustainability considerations, offering insights into the future configuration of EV motors.