High‐Temperature Polymer Composite Dielectrics: Energy Storage Performance, Large‐Scale Preparation, and Device Design

Abstract Film capacitors are widely used in advanced electrical and electronic systems. The temperature stability of polymer dielectrics plays a critical role in supporting their performance operation at elevated temperatures. For the last decade, the investigations for new polymer dielectrics with high energy storage performance at higher temperatures (>200 °C) have attracted much attention and numerous strategies have been employed. However, there is currently still a large gap between lab research and large‐scale production. In this review, the main effects of high temperature on the dielectric properties are analyzed and core modification strategies are summarized. The scientific and technological reasons for the performance difference between lab research and practical application are also discussed. Further, several processes for large‐scale film preparation and typical device structure design are reviewed. The current research and product launches pertaining of high‐temperature film capacitors are also summarized. Conclusive insights and future perspectives are delineated to offer strategic direction for the ongoing and prospective innovation in polymer dielectric materials.