Dr. Qi Li
Dr. Qi Li
Tsinghua University, China
Title: Structure Optimization to Polymeric Dielectric Materials for Advanced Film Capacitors
Polymeric dielectric materials enable film capacitor technology that is critical in high-power energy storage and pulsed power systems, hybrid electric vehicles, aerospace power conditioning and advanced electromagnetic weapons. Conventional high-temperature polymeric dielectric materials dissipate a large amount of heat as they are involved in continuous operations under high temperature and strong electric field conditions,which, unfortunately, leads to thermal runaway and failure of film capacitors. We propose to tackle the key issues associated with thermal runaway in plastic film capacitors by focusing on the suppression of charge injection from electrodes and thermally activated migration of charge carriers,rather than following the traditional design of high-temperature polymer dielectrics that only concerns the thermal stability of materials. Advanced composite approaches,thin-film deposition technologies, comprehensive characterizations of dielectric and capacitive energy storage properties as well as computational simulations are utilized to cover from structure control to material preparation, to performance assessment and to device modeling. The ultimate goal of this study is to develop novel high-temperature polymer dielectrics that can maintain dielectric stability and energy storage properties under high electric field and high temperature, and effectively suppress the thermal runaway of plastic film capacitors.
Qi Li received his Ph.D. degree in Materials Science at Wuhan University of Technology in 2013. From March of 2013 to November of 2016, he was a postdoctoral fellow at the Department of Materials Science and Engineering of the Pennsylvania State University. He started his appointment as an Associate Professor atthe Department of Electrical Engineering of Tsinghua University in December 2016. His research interest has been focusing on polymer-based nanocomposite materials with unique dielectric properties for electrical energy storage and conversion.His main scientific contributions include the development of state-of-the-art ferroelectric polymer nanocomposites for electrical energy storage and electrocaloric refrigeration applications, and the understanding of dielectric properties of polymeric materials under high electric fields and elevated temperatures. He has published over 50 SCI-indexed papers in journals such as Nature, PNAS, Nature Communications and Advanced Materials. He is the Guest Editor of Special Issue “Polymers for Film Capacitors” published by Materials, and an Editorial Board Member of IET Nanodielectrics. He was the recipient of the MRS Postdoctoral Award in 2016.