Regulating Li Extraction in Transition Metal Layer for High-Performance Li-Excess Layered Oxide Cathode with...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Lithium-excess layered oxide cathodes offer high capacity via anionic redox.
• However, lithium extraction can cause irreversible structural changes.
• Conventional edge-shared configurations facilitate detrimental lithium migration.

Purpose of the Study:

• To investigate a face-shared configuration to limit interlayer lithium migration.
• To develop a strategy for enhanced structural reversibility in lithium-excess cathodes.

Main Methods:

• Synthesized Li-excess cathode via Na-to-Li ion exchange in a P2 phase precursor.
• Utilized oxygen-stacking engineering to create an O2/O6 intergrowth structure.
• Characterized structural stability and lithium ion mobility during charging.

Main Results:

• Successfully obtained the face-shared configuration, restricting interlayer Li[TM] migration.
• Observed suppressed formation of vacancies and O-O dimers in transition metal layers.
• Achieved enhanced structural reversibility, capacity, and voltage retention.

Conclusions:

• Oxygen-stacking engineering is a viable strategy for improving cathode stability.
• The face-shared configuration effectively mitigates detrimental structural rearrangements.
• This approach offers a pathway to advanced lithium-ion battery cathodes.