Electrical Shorting between the Carbon-Fiber Cloth Electrodes of Structural Capacitors with a Glass-Fiber Cloth Separator

Akira Todoroki, Hiroko Shiomi, Yoshihiro Mizutani, Yoshiro Suzuki

Department of Mechanical Sciences of Engineering, Tokyo Institute of Technology, Tokyo, Japan.
Tokyo Institute of Technology, Tokyo, Japan.

DOI: 10.4236/ojcm.2014.43016                

Abstract

Multifunctional composites that have the ability to store or generate energy have attracted huge attention recently. One type of multifunctional composite is a structural capacitor that uses carbon fiber cloth as electrodes separated by glass-fiber cloth. However, such structural capacitors are difficult to fabricate reliably because electrical shorts sometimes form between the electrodes. In the present study, we investigate the mechanism of electrical shorting in such capacitors, which allows us to propose an improved fabrication process to prevent electrical shorting between the carbon-cloth electrodes. Infrared thermography reveals that electrical shorting between the electrodes is caused by contact between the carbon-fiber electrodes. Such contacts are formed by movement of the glass fibers of the separator during curing, which is induced by epoxy resin flow. Pre-curing of the glass-fiber cloth separator to a suitable degree ensures that the electrical insulation between carbon-fiber electrodes is reliable.

Keywords

Polymer Composites, Multifunctional Composites, Electrical Properties, Structural Capacitor

Conflicts of Interest

The authors declare no conflicts of interest.

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