Abstract
Lithium ion capacitor is a hybrid technology that integrates high surface area carbon cathode and prelithiated lithium anode materials to deliver a high energy density, high power density energy storage solution with good cycle life. In this investigation, we report the synthesis of a bimodal porous carbon electrode derived from polymer precursor for use as cathode with optimum hierarchical porosity that can deliver high specific capacitance and good high voltage electrochemical stability. Additionally, we also demonstrate the possibility of prelithiation of various graphitic materials for use as anode. Specifically, we fabricate a coalesced carbon onion based anode with rate capability as high as 100C. The assembled lithium ion capacitor shows over 80% capacitance retention over 21000 cycles. We also show that it is possible to package these materials in a 2016 coincell prototype and deliver an energy density of 13 Wh/L volumetrically based on packaged device. The device has been shown to be useful in developing self-powered health sensor platforms.