Preparation of SixCo0.3Cu0.3Cr0.6Al0.2/modified graphite sphere composites and their electrochemical performance as anode materials for Li-ion batteries

Abstract

Abstract New anode composite materials comprising Co, Cu, Cr, Al and Si in conjunction with graphite for Li-ion batteries are synthesized using high energy ball milling (HEBM) technique. The microstructure and morphology of the ball-milled Si x Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /modified graphite sphere composites (labeled as Si x Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /MGS, x = 1.12, 1.74, 2.84) are characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). In addition, X-ray photoelectron spectroscopy (XPS) is used to detect the chemical compositions of Si 2.84 Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 and Si 2.84 Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /MGS surfaces. The electrochemical behaviors of Si x Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /MGS are investigated by cyclic voltammetry (CV) and galvanostatic charge–discharge techniques. With the decrease of Si content, the specific capacity of Si x Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /MGS decreases, but the capacity retention becomes better. Among them, Si 1.74 Co 0.3 Cu 0.3 Cr 0.6 Al 0.2 /MGS presents good cyclic performance with a high reversible capacity (about 600 mA h g −1 ).