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

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