Enhanced energy storage performance of nano-submicron structural dielectric films by suppressed ferroelectric phase aggregation
Kun Xing, Yanan Hao, Xinjie Wang, Lei Huang, Yuan Gao, Liang Tong, Yan Meng, Ke Bi, Shao‐Long Zhong, Zhi‐Min Dang
Abstract
Maintaining high charge/discharge efficiency while enhancing discharged energy density is crucial for energy storage dielectric films applied in electrostatic capacitors. Here, a nano-submicron structural film comprising ferroelectric material P(VDF-HFP) and linear dielectric material PMMA has been flexibly designed via the electrospinning process. Nano-submicron structure enables the film to maximize the ferroelectric material component and obtain improved dielectric performance without sacrificing breakdown strength and charge/discharge efficiency. As a result, the 40%-420 nm PMMA-P(VDF-HFP)@PMMA sample achieved an discharged energy density of 13.72 J/cm³ at a field of 740 kV/mm, with an impressive charge/discharge efficiency of 80%. This work presents a composite dielectric film that excels in breakdown strength, discharged energy density, and charge/discharge efficiency, offering a strategy for designing reliable, industrial-grade energy storage dielectrics. The authors prepare an all-organic dielectric film with a nano-submicron surface layer via electrospinning technology, achieving a simultaneous improvement in the discharged energy density and charge/discharge efficiency.