Activate 1-TM Channel of Disordered Rock Salts via Electrostatic Repulsion Regulation for Enhanced Lithium Storage

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Disordered rock-salt (DRX) cathodes offer high capacity for Li-ion batteries.
• DRX materials face kinetic limitations due to restricted Li+ diffusion pathways.

Purpose of the Study:

• To activate the 1-transition metal (1-TM) Li+ diffusion channel in DRX cathodes.
• To establish a 3D Li+ diffusion network and overcome kinetic bottlenecks.

Main Methods:

• Utilizing electrostatic repulsion regulation to modify DRX lattice structure.
• Investigating changes in tetrahedral site geometry and Li+ migration energy barriers.
• Characterizing electrochemical performance, including capacity and rate capability.

Main Results:

• Activation of the 1-TM channel led to increased tetrahedral height and volumetric expansion.
• Significantly reduced Li+ migration energy barrier from 1.48 to 0.26 eV.
• Achieved high capacity (306 mAh g-1 at 10 mA g-1) and rate capability (~200 mAh g-1 at 100 mA g-1).

Conclusions:

• Electrostatic repulsion regulation is an effective strategy to enhance Li+ transport in DRX cathodes.
• This approach establishes a well-connected 3D Li+ diffusion network, addressing kinetic limitations.
• The findings provide a design paradigm for advanced disordered cathode materials.