Surface-Engineered Li₄Ti₅O₁₂ Nanostructures for High-Power Li-Ion Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Conventional lithium-ion batteries face power limitations due to slow charge-discharge rates.
• High-power materials are crucial for overcoming these limitations in energy storage applications.
• Lithium titanate (Li4Ti5O12) is a promising anode material for high-rate lithium-ion batteries.

Purpose of the Study:

• To develop a novel synthesis method for Li4Ti5O12 nanoparticles with enhanced high-rate capabilities.
• To investigate the structural properties and their correlation with electrochemical performance.
• To demonstrate a high-power lithium-ion battery utilizing the synthesized Li4Ti5O12 anode.

Main Methods:

• Solvothermal synthesis of Li4Ti5O12 nanoparticles using an off-stoichiometric precursor ratio.
• Characterization of material structure and morphology.
• Electrochemical testing of half-cells and full cells at various charge-discharge rates and temperatures.

Main Results:

• A unique Li4Ti5O12 nanoplate structure with a disordered surface layer was formed via controlled aging.
• The material exhibited ultrahigh-rate performance (50-300C) with reversible capacities of 156 and 113 mAh g⁻¹.
• A full cell with a LiMn2O4 cathode demonstrated ultrafast charging (140s) and discharging (12s) over a wide temperature range.

Conclusions:

• The developed solvothermal method yields Li4Ti5O12 nanostructures with exceptional rate capability.
• The disordered surface layer plays a critical role in enabling ultrahigh-rate performance.
• This Li4Ti5O12 anode is suitable for high-power lithium-ion batteries operating across diverse temperatures.