Energy storage devices which can bridge the gap between the energy density of Lithium ion battery and the power density of electric double layer capacitor have been gaining interest. Lithium ion capacitor (LIC), with its unique charge storage mechanism with hybrid/composite electrodes is one such device which has attracted much research recently ^{1, 2}. We report here a Hybrid LIC consisting of a Lithium Iron Phosphate (LFP) / Activated Carbon (AC) composite cathode in a synergetic ratio combination, while elaborating on the charge sharing and transition between the faradaic and non-faradaic reactions in the hybrid device. The results from this investigation of energy and power performance, cycle life and anode effects will be presented. The preliminary results, Figure 1, show that during the cycle life study carried out at a very high C- rate of 60C, the LIC device displays a very high capacity retention with no evident capacity decay (retention of 99.99%) over 15000 cycles (ongoing), while delivering an energy density of 70 Wh/Kg _{act. wt.+ Li-Loading} at 1C rate.

1. Wang B, Wang QM, Xu BH, Liu TF, Wang DL, Zhao G. The synergy effect on Li storage of LiFePO₄ with activated carbon modifications. RSC Adv. 3, 20024–20033 (2013).
2. Shellikeri, A., Hung, I., Gan, Z., Zheng J.P. In situ NMR Tracks Real-Time Li Ion Movement in Hybrid Supercapacitor - Battery Device, J. Phys. Chem. C, 120, 6314-6323 (2016).