Thermal management of electric motors using integrated thermoelectric cooling and flat heat pipes

A hybrid thermal management system integrating thermoelectric cooling with a flat heat pipe was developed to enhance heat dissipation in electric motors. System effectiveness under varying input voltage and electric motor power consumption ( W CP ) was evaluated using three metrics: the thermal regulation capability coefficient ( η TE ), thermal management index ( TMI ), and coefficient of performance ( COP ). Experimental and numerical results demonstrated that optimal performance occurred at 26 V and 269 W, with a temperature reduction of 41.58 K, a relative η TE of 2.63, and a relative TMI of 5.66 compared with the baseline, while maintaining a COP of 1.21. Although a higher COP of 2.63 was observed at 16 V, the limited cooling capacity and increased power consumption made this condition energetically inefficient. The flat heat pipe integrated heat sink achieved a minimum thermal resistance of 0.1005 K·W -1 , surpassing conventional strategies by more than 60% in terms of both temperature uniformity and thermal regulation capability coefficient. A key innovation was the optimization of voltage-based cooling and Joule heating mitigation, which enabled an optimal balance between cooling capacity and energy consumption. The system maintained stable cooling performance under reduced power input, thereby providing a theoretical foundation and practical guidance for thermal management optimization in high-power-density motors, system integration, and next-generation motor design. Design and working principle of a hybrid thermal management system for electric motors • Thermal management of electric motors is discussed. • Thermoelectric cooling modules coupled flat heat pipes enhance thermal management. • Thermal management index is proposed to evaluates cooling performance. • A rise in electric motor power consumption enhances the η TE . • Maximum temperature reduction, η TE , and TMI are 41.58K, 2.63, and 5.66.