Ulsan National Institute of Science and Technology
Abstract
School of Energy and Chemical Engineering (Chemical Engineering)An artificial cathode-electrolyte interphase (CEI) layer was employed on graphite to improve the anion intercalation reversibility for dual ion batteries (DIBs). An interesting LiF morphology feature was developed to have a nanometer-thick LiF skin on each graphite particle with a micrometer-thick LiF deposit on the electrode. The LiF skin/deposit nexus assembly on graphite played a role of: (1) facilitating anion intercalation kinetics, (2) alleviating volume expansion of graphite cathode and (3) suppressing electrolyte decomposition. Resultantly, it prolonged the cycling durability up to 86% capacity retention after 3000 cycles for the DIB cells having the natural graphite with the LiF-rich skin as the cathode with lithium metal anode (NG@LiFLi). Also, there was an insignificant capacity decay when the NG@LiFLi cell was charged even at 30C. Furthermore, the dual graphite battery (DGB) cell with NG@LiF cathode showed 97 % capacity retention up to 400 cycles.ope
