Tailoring Graphite Interlayers with Electron-Acceptor Bridges Raises Ion Diffusion Kinetics for Ultrafast Charging...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Sluggish lithium-ion diffusion in graphite anodes limits fast-charging capabilities.
• Tuning graphite interlayers with pre-intercalated molecules can improve charge transfer, but systematic design is lacking.

Purpose of the Study:

• To design and develop electron-acceptor aluminum chloride species intercalated into graphite (AC-G) for accelerated lithium-ion charge transfer.
• To investigate the impact of electron-acceptor bridges on lithium-ion diffusion kinetics within graphite interlayers.

Main Methods:

• Computational simulations guided the design of electron-acceptor species.
• Aluminum chloride species were intercalated into graphite (AC-G).
• Electrochemical performance, including lithium-ion diffusion coefficients and cycling stability, was evaluated.

Main Results:

• AC-G demonstrated a two-order-of-magnitude enhancement in lithium-ion diffusion coefficient (5.85 × 10^-7 cm² s^-1).
• Achieved stable cycling over 2000 cycles with high capacity retention (3.84 mAh cm^-2 at 1C) and 500-cycle stability at 5C.
• An Ah-level pouch cell with AC-G achieved an energy density of 285 Wh kg^-1 at 3C.

Conclusions:

• Introducing interlayer electron-bridging structures via aluminum chloride intercalation is a viable strategy for enhancing graphite anode performance.
• This approach offers valuable insights for developing next-generation fast-charging lithium-ion batteries.
• The developed AC-G material shows significant potential for practical applications in high-performance batteries.