Structural, compositional and electrochemical properties of Aluminium-Silicon-Chromium alloy thin film as anode for Lithium thin film battery

Abstract

In recent years, many new materials have been investigated in order to meet the need of high energy density for thin film batteries.Silicon based anode materials are attracting wide attention because of the highest theoretical capacity.By using DC magnetron sputtering method Aluminium film was deposited on ceramic substrate which acts as a current collector.Nanocrystalline film of Aluminium-Silicon-Chromium(Al-Si-Cr) alloy was deposited on aluminum film by using same sputtering method.High purity Aluminium-Silicon-Chromium metal alloy sputtering target was used for the film deposition.For comparison of anode cycling performance, pure Silicon thin films were also prepared by using same sputtering method.Al-Si-Cr films were analysed by XRD, EDAX, AFM and SEM .The crystallite size was determined by FWHM of XRD peaks.Particle size and microstructure of the film have been studied by SEM and AFM.The Al-Si-Cr thin film composition was analysed by EDAX.Composition ratio between Aluminium Silicon and Chromium obtained by EDAX is 2:3:5.Electrochemical properties of the films were analyzed by preparing lithium battery cell.Lithium insertion and excretion was performed by Cyclic Voltametry.Effect of cycling on structure stability of Al-Si-Cr anode film was studied by SEM analysis.