Growth and electrochemical properties of Li-Ni-Co-Al oxide films
Résumé
LiNi0.8Co0.15Al0.05O2 films were grown by pulsed-laser deposition (PLD) in the temperature (T-s) range of 30-500 degrees C and oxygen partial pressure (p(O2)) maintained in the range of 50-150 mTorr. The grown films were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy (RS), and electrochemical measurements in order to understand their growth behavior, surface morphology, local chemical structure, and electrochemical properties. XRD, RS, and SEM measurements indicate that the growth and microstructure of PLD LiNi0.8Co0.15Al0.05O2 films are highly sensitive to the deposition temperature and reactive atmosphere during laser ablation. The fabrication conditions were optimized to produce device quality LiNi0.8Co0.15Al0.05O2 films for electrochemical applications. The charge-discharge profiles of cells using the PLD grown Li(Ni, Co, Al)O-2 films as electrodes demonstrate their applicability in microbatteries. A stable capacity of 98 mu A h/cm(2) mu m was obtained in the potential range of 4.2-2.5 V for LiNi0.8Co0.15Al0.05O2 films grown at 450 degrees C. (c) 2007 American Vacuum Society.