High-Energy-Storage Dielectric Performance of Sandwich PI-Based Composite over a Wide Temperature Range

The application of film capacitors is limited by their poor energy storage performance and stability at high temperatures. So far, most work has been concentrated on the use of single-dimensional inorganic fillers incorporated into polymers, but it is difficult to improve the breakdown strength and polarization simultaneously, especially at high temperatures (>150 degrees C). We prepared (Al2O3-TiO2-Al2O3)/PI composite films by capitalizing on the benefits of distinct dimensional materials in terms of electrical and thermal properties. The experimental results show that through the reasonable multidimensional coordination design, the composite film exceeds many current high-temperature-resistant materials and can be used up to 200 degrees C. With the optimal filler ratio, the maximum energy density and efficiency could remain as high as 2.31 J/cm(3) and 81% at 200 degrees C, respectively. This work demonstrates an excellent method to further improve the energy density and discharge efficiency for high-temperature dielectric polymer-based composites.