Atomistic Observation on Lithiation and Delithiation Behaviors of Silicon Nanowires: Reactive Molecular Dynamics Simulation
- Atomistic Observation on Lithiation and Delithiation Behaviors of Silicon Nanowires: Reactive Molecular Dynamics Simulation
- 정현; 주재용; 이광렬; 한상수
- Silicon nanowire; lithiation; Reactive force field; Molecular dynamics simulation
- Issue Date
- 17th International Meeting on Lithium Batteries
- Recently silicon has attracted intense interest as a promising anode material of lithium-ion
batteries due to its extremely high capacity of 4200 mA/g (for Li4.2Si) that is much higher
than 372 mAh/g (for LiC6) of graphite. However, it seriously suffers from large volume
change (even up to 300%) of the electrode upon lithiation, leading to its pulverization or
mechanical failure during lithiation / de-lithiation processes and the rapid capacity fading.
To overcome this problem, Si nanowires have been considered. Use of such Si nanowires
provides their facile relaxation during lithiation / de-lithiation without mechanical breaking.
To design better Si electrodes, a study to unveil atomic-scale mechanisms involving the
volume expansion and the phase transformation upon lithiation is critical. In order to
investigate the lithiation mechanism in Si nanowires, we have developed a reactive force
field (ReaxFF) for Li-Si systems based on density functional theory calculations. The
ReaxFF method provides a highly transferable simulation method for atomistic scale
simulation on chemical reactions at the nanosecond and nanometer scale. Molecular
dynamics with the ReaxFF reproduces well experimental anisotropic volume expansion of
Si nanowires during lithiation and diffusion behaviors of lithium atoms, indicating that it
would be definitely helpful to investigate lithium mechanism of Si electrodes and then
design new Si electrodes.
- Appears in Collections:
- KIST Publication > Conference Paper
- Files in This Item:
There are no files associated with this item.
- RIS (EndNote)
- XLS (Excel)
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.