Benchmarking of Traction Electric Machines Considering Sustainability and Performance

Transportation electrification demands traction motors that balance performance with sustainability. This paper benchmarks 16 commercial and prototype battery-electric vehicle machines across five motor topologies, integrating electromagnetic, thermal, and mechanical performance with material-based sustainability assessment. Active-material inventories are evaluated using the Idemat 2026 life-cycle inventory database and its Eco-cost indicator under open- and closed-loop recycling scenarios. The benchmark shows that EESMs can approach PMSM-level power density, with the best cases reaching about 45 kW/L without using rare-earth permanent magnets. Advanced oil and hybrid cooling architectures enable 60-80% higher torque density, reducing material consumption. Idemat's resource-scarcity weighting assigns the highest burden to rare-earth elements, followed by copper. Aluminium conductors remain a more sustainable option on a volume basis in both open-and closed-loop scenarios. Overall, the results show that recycling and cooling-driven compactness strongly affect the sustainability ranking of machines, making the proposed framework a support tool for early-stage design comparison.