Electrochemical and Structural Investigations of xLiLi_(0.33)Mn_(0.66)O_2 (1-x)LiNi_(0.8)Co_(0.15)Zr_(0.05)O_2 (0.3≤ x ≤ 0.7) Composite Layered Oxide Cathode for Rechargeable Lithium Ion Batteries

摘要

The potential for high power lithium ion batteries have made them one of the most attractive candidates for electric as well as hybrid electric vehicles. As cathode material for lithium ion rechargeable batteries, the lithium based layered as well as spinel oxides remain attractive candidates. The capacity of these cathodes has so for been limited to 160 mAh/g in most cases and their electrochemical performance strongly depended on the synthesis conditions. With the aim to increase the discharge capacity beyond 160 mAh/g with the improved cycleability and rate capabilities, in the present work, we have synthesized a solid solution series of layered xLi[Li_(0.33)Mn_(0.66)]O_2(1-x)Li[Ni_(0.8)Co_(0.15Zr_(0.05)]O_2 (0.3≤x≤0.7) by wet chemical route. The XRD pattern analysis has been utilized to characterize the structural changes of the active component as a function of the inactive oxide component and XPS has been used to find oxidation/reduction behavior over the surface of cathode material. The mechanism of Li overcapacity during electrochemical charging is believed to be due to oxygen loss and the conversion of inactive material to active one.