Atomistic Simulation Study of Lithium Manganese Oxides for Li-Ion Batteries

Simulated amorphisation recrystallisation (A+R) technique has been successfully used to generate models of various nano-forms of the complex manganese dioxides [1]. We apply the method to study lithium insertion into the nano - spheres, sheets, rods and porous structures of the binary MnO$_{2}$. The variation of mechanical properties and microstructural features with lithium concentration are investigated. The bulk ternary Li$_{2}$MnO$_{3}$ provides structural integrity for lithium-ion battery cathodes and is electrochemically inactive. The nanocrystalline Li$_{2}$MnO$_{3}$ has a structure similar to that of the bulk, but shows different lithium intercalation properties [2]. We simulated such a nanophase by the A+R method, and the resulting microstructures provide insights into the origins of the electrochemical activity which renders it suitable for battery electrodes. \\[4pt] [1]. T.X.T. Sayle, R.R. Maphanga, P.E. Ngoepe, and D.C. Sayle, J. Am. Chem. Soc., 131, 6161, (2009).\\[0pt] [2]. G. Jain, J. Yang, M. Balasubramanian and J,J. Xu, Chem. Mater. \textbf{17}, 3850, (2005)