Morphological, electrochemical and in-situ XRD study of LiNi0.6Co0.2Mn0.1Al0.1O2 as high potential cathode material for rechargeable lithium-ion batteries

摘要

By using a simple high temperature solid state reaction, LiNi0.6Co0.2Mn0.1Al0.1O2 is prepared via Ni site dual substitution with Mn and Al. Structural observation reveals that the as-prepared sample can be indexed to an alpha-NaFeO2 type single phase with R-3m space group. Morphology and particle size investigations present that Mn and Al co-doped LiNi0.8Co0.2O2 is composed of micro-sized secondary particles (5-20 mu m) agglomerated from highly packed primary particles (1-2 mu m). Charge-discharge tests demonstrate that LiNi0.6Co0.2Mn0.1Al0.1O2 can reversibly react with lithium between 2.5 and 4.9 V with a high discharge capacity of 202.0 mAh g(-1). This favorable electrochemical performance is attributed to the stable crystal structure after Mn and Al dual doping. This quasi-reversible structural change is also proved by in-situ X-ray diffraction study in this work. (c) 2016 Elsevier B.V. All rights reserved.