Performance improvement of Li-rich layer-structured Li(1.2)Mn(0.54)Ni(0.13)Co(0.13)O2 by integration with spinel LiNi(0.5)Mn(1.5)O4

Phys Chem Chem Phys. 2015 Jan 14;17(2):1257-64. doi: 10.1039/c4cp04087b. Epub 2014 Nov 25.

Abstract

Li-rich layered Li1+xMnyM1-x-yO2 (or denoted xLi2MnO3·(1 -x)LiMO2, M = Ni, Co, Mn, etc.) are promising cathode materials for high energy-density Li-ion batteries. However, their commercial applications suffer from problems such as a drop in the capacity and discharge voltage during cycling. In this work, the cycling performance of a layered oxide Li1.2Ni0.13Co0.13Mn0.54O2 is improved by integration with spinel LiNi0.5Mn1.5O4 to obtain a layered-spinel composite. Characterization by powder X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) as well as cyclic voltammetry (CV) indicates that delayed degradation of layered Li2MnO3 and the suppressed growth of LiMn2O4-like spinel are responsible for the performance improvement.