Lattice engineering and ion conduction in halide solid-state electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Halide superionic conductors are promising solid-state electrolytes for all-solid-state lithium-ion batteries.
• Understanding ion transport is crucial for improving ionic conductivity and discovering new fast ion conductors.

Purpose of the Study:

• To elucidate structural principles governing ion transport in halide superionic conductors.
• To provide a unique perspective on ion conduction mechanisms for designing future solid electrolytes.

Main Methods:

• Review of structural factors controlling ionic conduction in solid electrolytes.
• Emphasis on dynamic lattice disorder, frustration-assisted transport, and amorphous-enabled conduction.
• Analysis of lattice structure and local structural effects on ion transport.

Main Results:

• Identified dynamic lattice disorder and amorphous structures as key factors in halide superionic conductivity.
• Shifted focus from static descriptors (ionic radius, polarizability, vacancy concentration) to dynamic aspects.
• Highlighted the role of local structural effects in ion transport.

Conclusions:

• Dynamic lattice disorder, frustration-assisted transport, and amorphous structures are critical for high ionic conductivity in halide solid electrolytes.
• A new perspective on ion conduction mechanisms can inspire the development of advanced solid electrolyte materials.
• This work provides insights for designing next-generation solid electrolytes for batteries.