This paper investigates the relaxor ferroelectric polymer-poly(vinylidene fluoride/trifluoroethylene/chlorofluoroethylene) terpolymer for energy storage capacitors. It is found that the high dielectric constant (> 50 at 1 kHz) and high reversible polarization in the terpolymer lead to a high electric energy density ∼10 J/cm3, achieved under an electric field of more than 350 MV/m. The high dielectric constant also causes the polarization saturation at fields much below the breakdown field and whereby the discharged energy density increases nearly linearly with applied field, distinctively different from the low dielectric constant linear dielectric polymers whose energy density rises with square of the applied field. The strong frequency dispersion and nonlinear polarization response (polarization saturation) of the relaxor terpolymer result in a low effective capacitance at the beginning of the discharge and the effective capacitance increases with time during the discharge. Furthermore, due to the frequency dispersion and nonlinear effect, the discharged energy density of the terpolymer to a resistor load RL increases with RL. A large RL will lead to high discharge efficiency in the terpolymer capacitor.
|Original language||English (US)|
|Number of pages||7|
|Journal||IEEE Transactions on Dielectrics and Electrical Insulation|
|State||Published - Oct 1 2006|
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering