Combinatorial Study of the Li-Ni-Mn-Co Oxide Pseudo-Quaternary System for use in Li-ion Battery Materials Research

Abstract

Samples of the Li-Ni-Mn-Co-O system were prepared using a combinatorial and high throughput method at two separate cooling rates and were subsequently studied by X-ray diffraction to determine the crystal structure of each sample. Two separate series were investigated. The first series spanned the entire pseudo-ternary phase diagram planes defined at the cobalt fractional metal contents of 10%, 20% and 30% in the Li-Ni-Mn-Co-O system and the second series spanned the entire Li-Co-Mn-O pseudo-ternary phase diagram. Retrieved crystal structure data for each sample was used to map the phase diagrams of the targeted regions. Two large single-phase regions were observed: the layered region and cubic spinel region. Materials contained in these systems are of high interest for finding improved cathode materials for use in lithium-ion batteries.