Development of advanced polymer nanocomposite capacitors

With the development of modern technology, the demand of high energy density dielectric capacitor devices is increasing for its significant role in stationary power systems, mobile devices, and pulse power applications. Among the different energy storage devices, polymer film based dielectric capacitor is still one of the most widely used energy storage devices mainly due to its high energy density, significant higher charge/discharge rate and low cost. To further enhance the energy density, high dielectric ceramic inclusions have been embedded in the polymer matrix; however, the temperature influence on the energy density has not been investigated. Therefore, in this research work we fabricated BaTiO3/PVDF and BaTiO3/PI nanocomposites with different volume fractions of high dielectric constant ceramic filler materials and high dielectric breakdown strength polymer materials by solution casting method to explore their energy densities at temperature ranges from 20°C to 120°C. Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) were used for materials characterization. Capacitance and breakdown strength were measured to determine the energy density of the samples for BaTiO3/PVDF nanocomposites with 0%, 10%, 20%, 30% and 40% volume fractions of BaTiO3 with the PVDF matrix. For BaTiO3/PI nanocomposites, 0%, 5%, 10%, 15% and 20% volume fractions of BaTiO3 was used with the PI matrix. The resulting dielectric film capacitors displayed improved energy densities to meet the future demands of energy storage applications