Design and performance of multifunctional structural composite capacitors

Dielectric capacitors with mechanical load-bearing capability have been constructed by laminating glass-epoxy prepregs with metalized film electrodes. Mechanical characterization and high-voltage testing are used to quantify the elastic modulus, mechanical strength, and dielectric energy density of these structural devices. An approach for predicting mass savings in systems utilizing multifunctional material structures is also presented. The experimental results show that, in spite of increases in void content with fiber volume fraction, overall structural capacitor performance is greatest at maximum fiber volume fraction. At these high-fiber volume fractions, the overall multifunctional performance of the structural capacitors is predicted to provide mass and volume savings over conventional designs.