Sandwiched Barium Titanate/Polyamideimide Nanocomposite for Dielectric Energy Storage

Electrical insulation represents a critical application for polymers in electric and electronic power systems. Polymer based dielectrics with highly insulating capability combined with remarkable high permittivity are promising candidates for electrostatic energy storage in electronic power systems. Constructing polymer nanocomposites by introducing inorganic nano fillers with high permittivity in polymer matrix has been recognized as an effective way to achieve enhanced energy density, while, however, the fillers could provide conductive paths for charge carriers, thus leading to the increase of electrical conduction. It is found that layered structure design enables polymer nanocomposites with much enhanced breakdown strength and suppressed leakage current, compared with traditional single-layered counterparts. In this work, we manufactured a barium titanate/polyamideimide composite film with a sandwiched structure. In this structure, the middle layer containing ceramic nanoparticles are clapped between two pristine polymer layers, which prevent charges that are injected from electrodes to go through the film. Significantly enhanced charge-discharge efficiency and energy density is obtained through this structural design, which can enable a wide range of polymers for the improvement of energy storage performance.