In Situ AFM Study of Solid Electrolyte Interface in Lithium-Ion Batteries

Abstract

Chemical and morphological structure of solid electrolyte interphase (SEI) plays a vital role in lithium-ion battery (LIB), especially for its cycleability and safety. To date, research on SEI is quite limited due to the complexity of SEI and lack of effective in situ characterization techniques. Here, we present real-time views of SEI morphological evolution using electrochemical atomic force microscopy (EC-AFM). Complemented by an ex situ XPS analysis, fundamental differences of SEI formation from ethylene carbonate (EC) and fluoroethylene carbonate (FEC)-based electrolytes during first lithiation/delithiation cycle on HOPG as well as Fe3O4 electrode surfaces were revealed. Our results sho..