Regulating the Performance of Lithium-Ion Battery Focus on the Electrode-Electrolyte Interface

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• The solid electrolyte interface (SEI) film is critical for lithium-ion battery (LIB) performance and safety.
• Decades of research have focused on SEI layers, yet fundamental understanding of their composition and formation remains incomplete.
• Controversies persist regarding the exact mechanisms governing SEI layer development.

Purpose of the Study:

• To review recent advancements in understanding the interfacial film in LIBs.
• To consolidate knowledge on SEI film formation mechanisms, composition, and stability.
• To highlight methodologies for SEI characterization and suggest future research directions.

Main Methods:

• Literature review of recent research on LIB interfacial films.
• Analysis of studies focusing on SEI composition and stability, particularly on positive electrodes.
• Examination of advanced characterization techniques used for SEI analysis.

Main Results:

• Recent research has shed light on SEI film formation mechanisms and composition.
• The stability of interfacial films on positive electrodes varies with electrolyte concentration.
• Various advanced techniques are available for characterizing SEI layers.

Conclusions:

• Further fundamental research is needed to resolve controversies surrounding SEI formation and composition.
• Optimizing SEI layers is key to enhancing LIB cycle life and safety.
• Future work should focus on developing novel characterization methods and understanding SEI behavior in diverse electrolyte systems.