A Fast-Charge Graphite Anode with a Li-Ion-Conductive, Electron/Solvent-Repelling Interface

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Graphite is the primary anode material for rechargeable lithium-ion batteries.
• Current graphite anodes face limitations in fast charging due to structural defects and parasitic reactions.
• Existing surface modifications are insufficient for achieving practical fast-charge requirements.

Purpose of the Study:

• To enhance the fast-charging capability and long-term stability of graphite anodes.
• To overcome the limitations of conventional surface modifications for high-rate performance.
• To develop a novel interfacial engineering strategy for next-generation batteries.

Main Methods:

• Surface modification of graphite using a molybdenum oxide-molybdenum nitride (MoOₓ-MoNₓ) layer.
• Characterization of the modified anode's interfacial properties.
• Electrochemical testing to evaluate rate capability, capacity, and cycle life.

Main Results:

• The MoOₓ-MoNₓ layer facilitates rapid lithium-ion diffusion while preventing solvent co-intercalation and electron leakage.
• The modified graphite anode achieved a high reversible capacity of 340.3 mAh g⁻¹.
• Demonstrated excellent stability with 4000 cycles at 6 C, indicating long operational life.

Conclusions:

• The MoOₓ-MoNₓ interfacial layer is a promising strategy for fast-charging lithium-ion batteries.
• This approach effectively regulates interfacial mass and charge transfer for improved performance.
• The modified graphite anodes show potential for developing 10-minute rechargeable batteries with extended durability.