A S Prakash

Classical molecular dynamics and quantum abs-initio studies on lithium-intercalation in interconnected hollow spherical nano-spheres of amorphous Silicon

A high concentration of lithium, corresponding to charge capacity of ∼4200 mAh/g, can be intercalated in silicon. Unfortunately, due to high intercalation strain leading to fracture and consequent poor cyclability, silicon cannot be used as anode in lithium ion batteries. But recently interconnected hollow nano-spheres of amorphous silicon have been found to exhibit high cyclability. The absence of fracture upon lithiation and the high cyclability has been attributed to reduction in intercalation stress due to hollow spherical geometry of the silicon nano-particles.

Oxygen stability study of Li-rich compound: First Principle Analysis

High energy density Li-rich layered cathode materials suffer from structural instability at high voltage. It is known that oxygen stability influence the structural stability of Li2MO3 (M=Co/Mn/Ni). Oxygen stability with partial de-lithiation has not been clarified in presence of multiple d-orbital elements. This work presents density functional theory based study of Li1.17Ni0.17Mn0.67O2. In the series of Li-rich compounds, end point material is Li2MnO3, in which oxidation of Mn4+ compensates with oxidation of O2- to O2 while charging.