UT Materials Science & Engineering
Materials Structure Interactive Gallery

Molecular Dynamics Simulation of Lithium and Sodium Ion Transport in Hard Carbon

Abebaw Seyume
Department of Chemistry, University of Tennessee, Knoxville

This work investigates lithium (Li) and sodium (Na) ion transport in hard carbon using molecular dynamics simulations. Two interaction models were compared: Lennard-Jones (LJ) and ReaxFF. The ReaxFF model captures realistic ion intercalation and charge transfer, while the LJ model significantly overestimates ion mobility.

Lithium exhibits fast early-time diffusion followed by trapping, whereas sodium shows sustained hopping diffusion. Mean square displacement (MSD) analysis showed that the LJ model predicts unrealistically large diffusion due to the absence of reactive interactions. In contrast, ReaxFF simulations revealed stronger ion–carbon interactions and partial ion confinement within carbon layers.

Interactive Structures

Color Legend:
  • Blue = Lithium (Li)
  • Red = Sodium (Na)
  • Grey = Carbon (C)
References
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