Dielectric Studies in Materials for High Energy Density Capacitors
Abstract
The energy requirements of technologies today are more demanding than ever. The requirement for large energy storage and a quick release of that energy is becoming a greater and greater problem. Limited by size, cost, and the speed of chemical reactions, batteries need to be replaced as a primary source of stored energy. Capacitors have the ability to perform in many of the areas where batteries and other energy sources fall short. One way to increase the performance of a capacitor is by inserting a dielectric material. The dielectrics polypropylene and Ultem were the focus of this study, polypropylene as a control and Ultem due to its ability to handle high temperatures, structural stability, and good dielectric characteristics. Ultem was studied in both its pure form and with the addition of mesoporous silica, which theoretically should lead to an increase in dielectric performance while maintaining structural stability. This was done through the casting of Ultem films which underwent dielectric breakdown testing and broadband dielectric spectroscopy. Broadband dielectric spectroscopy analyzed the AC voltage and current relationship in materials at different frequencies and temperatures. The data produced allowed the calculation of the dielectric constant and loss and gives insight into these values. Dielectric strength measurement is a new experiment at the Naval Academy, so part of this project was to develop the methods to be used. This involved developing sample preparation techniques, voltage ramping procedures, and validations of the test equipment. Results confirm the This, however, was extremely dependant on the thickness of the material tested. Mesoporous silica was added to the Ultem in an effort to improve breakdown strength. However, when mesoporous silica was added to cast samples, the samples become brittle and had a drop in the breakdown strength.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 04, 2007
- Accession Number
- ADA473325
Entities
People
- Andrew J. Turo
Organizations
- United States Naval Academy