Investigation of Mechanical and Electrochemical Performance of Multifunctional Carbon-Fiber Reinforced Polymer Composites for Electrical Energy Storage Applications

Concept of structural supercapacitors, based on carbon fiber reinforced polymer composites, has been introduced that can act as a structural load bearing component as well as an electrical energy storing device simultaneously. This multifunctional carbon fiber reinforced structural supercapacitors are fabricated by using carbon fiber and glass fiber/filter paper as reinforcements and cross-linked polymer electrolyte as a matrix. Carbon fiber mats also simultaneously serve the role of electrodes in addition to reinforcements whereas the glass fiber mat/filter paper also acts as an insulator to avoid the short-circuiting of the carbon fiber electrodes. A polymer epoxy matrix is modified by introducing ions within the cross-linked structure in order to develop an optimized polymer electrolyte. Flexural tests of structural supercapacitor are conducted to evaluate the structural performance while charge/discharge tests are conducted to evaluate the electrochemical performance. Multifunctional structural supercapacitors are tested mechanically as well as electrochemically. A structural supercapacitor is fabricated showing simultaneously an energy density of 0.11 mWh m-3, a specific capacitance of 0.8 mF.cm-3 and a flexural modulus of 26.6 GPa simultaneously.