Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics
Numerous investigations have been carried out on the incorporation of high permittivity inclusions into polymeric hosts to develop dielectric composites with improved energy storage characteristics. Modest increases in the effective dielectric constant of the composite have been reported, but the energy storage density is not increased to the extent that would be expected considering the high permittivity inclusion phase, which is frequently barium titanate. Other investigations have focused on the use of liquid phase sintering for the elimination of porosity in ceramic dielectrics with the goal of minimizing field enhancements in the vicinity of pores and thus increasing breakdown strength and energy storage density. In this paper, we present preliminary results that simulate the electric field distribution in diphasic dielectrics that resemble these two classes of capacitive media. The effects of the volume fraction of the high permittivity phase on field distribution and energy storage density are considered. As expected, the electric field within the high permittivity inclusion is greatly reduced compared to the applied field, reducing the effective permittivity of the diphasic dielectric and the associated energy storage density. Future simulations will be carried out to identify optimum inclusion fractions, morphology, and distribution characteristics to maximize energy storage density. These studies should provide insight regarding the desirable microstructural features for diphasic dielectric bodies based on high permittivity inclusions.
R. W. Schwartz and S. K. Patil, "Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics," Proceedings of the 12th US-Japan Seminar on Dielectric and Piezoelectric Ceramics (2005, Annapolis, MD), Nov 2005.
12th US-Japan Seminar on Dielectric and Piezoelectric Ceramics (2005: Nov. 6-9, Annapolis, MD)
Materials Science and Engineering
National Science Foundation (U.S.)
United States. Office of Naval Research
Keywords and Phrases
Dielectric Composites; Electric Field Distribution; Energy Storage
Article - Conference proceedings