Amorphization of Inorganic Solid Electrolyte Interphase Components and Its Impact on Enhancing Their Transport and...

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• The solid electrolyte interphase (SEI) is crucial for lithium-ion battery (LIB) safety and lifespan.
• Understanding the properties of individual SEI components like lithium oxide, lithium carbonate, and lithium fluoride is limited.
• Their intrinsic roles in protecting LIB anodes are debated.

Purpose of the Study:

• To investigate the impact of amorphous SEI components on mechanical and transport properties.
• To compare the Li-ion conductivity of amorphous versus crystalline SEI phases.
• To explore stabilization strategies for amorphous SEI phases.

Main Methods:

• First-principles calculations were employed.
• Mechanical and transport characteristics of amorphous and crystalline SEI components were analyzed.
• Thermodynamic stability and the effect of impurities were studied.

Main Results:

• Amorphous SEI phases exhibit significantly higher Li-ion conductivity than their crystalline counterparts.
• Amorphous lithium fluoride demonstrates superior Li+ ion transport capabilities, challenging existing understanding.
• Amorphous SEI phases are thermodynamically unstable under ambient conditions, tending to recrystallize.

Conclusions:

• Amorphous SEI phases offer improved Li-ion conductivity, with amorphous LiF being particularly effective.
• Stabilizing these amorphous phases, potentially through nitrogen incorporation, is key to harnessing their benefits.
• This research provides insights into designing more robust and efficient SEI layers for LIBs.