The important role of additives for improved lithium ion battery safety

1,3-Propane sultone (PS) additive for graphite electrodes was studied for propylene carbonate (PC) and ethylene carbonate (EC)-based electrolytes in lithium batteries. Decomposition of solvents with graphite electrodes could be remarkably suppressed by addition of the PS additive in the PC-based electrolyte, leading to improvement of electrochemical performances of the cells. The 1,3-propane sultone additive showed very interesting properties for the graphite electrode. It is predicted to give a solid electrolyte interphase (SEI) on the surface of the graphite prior to solvent decomposition and bring about effects that not only suppress lithium deposition on the graphite electrode surface, but also accelerate lithium intercalation, leading to formation of LiC6 onto graphite electrode. (C) 2008 Published by Elsevier B.V.