7. Glossary –Definition

Solid Electrolyte Interphase (SEI)

Passive layer (organic and inorganic) formed on the surface of lithium metal by reaction with the electrolyte (lithium salt and solvent). This very thin layer (a few tens of nanometers) is conductive by lithium ions and electronically insulating.

Single ion Polymer

It's a polymer for which ionic conductivity is made possible by the displacement of a single type of ion. In the case of lithium batteries, the mobile ion is Li ⁺ . This property can be achieved by grafting onto the macromolecular backbone the anion that is thus immobilized on the polymer chain.