Electrochemical performance of LiNi1/3Co1/3Mn1/3O2 thin film electrodes prepared by pulsed laser deposition

Layered LiNi1/3Co1/3Mn1/3O2 thin film electrodes are successfully prepared by pulsed laser deposition technique and post-annealed. The microstructure of the thin films is characterized by X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and transmission electron microscopy. The electrochemical performance of the thin film electrodes is evaluated by cyclic voltammetry and galvanostatic charge-discharge measurements. The kinetics of Li diffusion in the thin film electrodes are investigated by galvanostatic intermittent titration technique. The annealed thin films exhibit a partially amorphous structure. The electrochemical performance of LiNi1/3Co1/3Mn1/3O2 thin film electrodes depends on the annealing temperature, composition and thickness. The thin film electrodes deposited for 30 min with the annealing temperature of 450 degrees C deliver the best electrochemical performance, including high capacities, good cycle performance and rate capability. The initial discharge capacity of the thin film electrodes is 177 mAh g(-1) measured at a rate of 0.1C in the voltage range of 2.8 -4.5 V. The capacity retention ratio is 92% after 25 cycles at 0.5C rate. The chemical diffusion coefficients of lithium ion in the thin film electrodes are in the range of 10(-9)-10-(10) cm(2) s(-1). (C) 2012 Elsevier B.V. All rights reserved.