Development of Sustainable Slot Liners for 800 V+ Oil-Cooled Electrical Machines for Passenger Cars

Journal article, 2025

This paper presents the development of a high-performance slot-liner solution based on thermoplastic PEEK Films tailored for the next generation of 800 V+ oil-cooled electric drive units in automotive applications. The work highlights the critical role of slot-liners as a fundamental component of primary insulation systems to enable the design of electric motors that achieve high efficiency and torque without compromising reliability. To meet the demanding dielectric performance requirements for 800 V+ e-motors, a material development study has been conducted. The results undermine the suitability of PEEK Films for high-voltage slot-liner applications upon meeting the oil compatibility and dielectric performance criteria for passenger cars and heavy-duty vehicles.