SAIP2014

Atomistic Simulation Studies of LiMn₂O₄

9 Jul 2014, 17:10

1h 50m

D Ring ground level

Board: A.180

Poster Presentation Track A - Division for Physics of Condensed Matter and Materials Poster2

Speaker

Ms Raesibe Sylvia Ledwaba (University of Limpopo)

Main supervisor (name and email)<br>and his / her institution

Prof. Phuti Ngoepe
phuti.ngoepe@ul.ac.za
University of Limpopo

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

The spinel LiMn₂O₄ is a promising cathode material for use in lithium-ion batteries. To identify the effects of temperature on this system, molecular dynamics simulations were carried out in the NVE ensemble using the supercell approach, on a supercell system consisting 12096 atoms. The radial distribution functions, diffusion coefficients, total energy and x-ray diffractions were analysed. The findings of this study indicated Li-Li bond shortening on the rdf plots, which was due to lithium ions hopping from 8a to 16c vacancies. Lithium diffusion plot indicates no diffusion when the structure is heated up to 280 K, just before the Verwey transition takes place (Tv =285 K). Immediately above the transition, the plot shows an increase at 290 K and then goes back to ~0nm2/s at 300 K. The lithium diffusion then increase until it starts decreasing above the melting point of the system (~2000 K). This shows that the lithium diffusion capacity of the battery material can withstand high temperatures without any compromise.

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

No

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

yes

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD)?

MSc