A New Perspective on the Formation and Structure of the Solid Electrolyte Interface at the Graphite Anode of Li-Ion Cells

Abstract

A new model describing the interactions between the graphite anode in batteries and the liquid electrolyte reduction products [the solid electrolyte interface (SEI)] is presented. According to this model, certain solvents and additives produce efficient passive films which mimic a double‐layer capacitor, wherein local, fixed positive charges in the SEI serve to counteract the negatively charged graphite anode. The model also suggests that internal passive layer interactions are of a multilayered capacitor type. Previously published experimental data in support of this model is presented. ©1999 The Electrochemical Society