Solid Electrolyte Interphase

Solid Electrolyte Interphase (SEI) is formed on electrode surfaces from decomposition products of electrolytes. The SEI allows Li+ transport and blocks electrons in order to prevent further electrolyte decomposition and ensure continued electrochemical reactions.

The solid electrolyte interphase (SEI) is primarily formed in the first battery cycle from the reduction of the electrolyte, and allows Li ion transport while preventing further electrolyte decomposition.

The SEI layer formation can be improved with electrolyte additives.


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