Publisher : The Korean Institute of Electrical Engineers
DOI : 10.5370/JEET.2015.10.3.1102
Title & Authors
The Surface Modification of Electrode with Solid Electrolyte Interphase for Hybrid Supercapacitor Choi, Min-Geun; Kang, Soo-Bin; Yoon, Jung Rag; Lee, Byung Gwan; Jeong, Dae-Yong;
A hybrid supercapacitor (HS) is an energy storage device used to enhance the low weight energy density (Wh/kg) of a supercapacitor. On the other hand, a sudden decrease in capacity has been pointed out as a reliability problem after many charge/discharge cycles. The reliability problem of a HS affects the early aging process. In this study, the capacity performance of a HS was observed after charge/discharge. For detailed analysis of the initial charge/discharge cycles, the charge and discharge curve was measured at a low current density. In addition, a solid electrolyte interphase (SEI) layer was confirmed after the charge/discharge. A HC composed of a lithium titanate (LTO) anode and active carbon cathode was used. The charge/discharge efficiency of the first cycle was lower than the late cycles and the charge/discharge rate was also lower. This behavior was induced by SEI layer formation, which consumed Li ions in the LTO lattice. The formation of a SEI layer after the charge/discharge cycles was confirmed using a range of analysis techniques.