Preparation and electrochemical performance of ball milling SiOx/(Cu,Ni) anode materials for lithium–silicon batteries

Abstract

In order to alleviate volume changes of silicon monoxide during lithium insertion and improve its electrical conductivity, ball milling(bm)-SiOx/(Cu,Ni) lithium-ion battery anode materials are successfully prepared by depositing copper and nickel on the surface of silicon nanoclusters of silicon monoxide by electroless plating. The composition and morphological characteristics of the prepared materials are characterized by XRD, XRF, XPS, TEM, and EDS, and the electrochemical performance behavior of the materials are investigated by electrochemical tests. The results show that when the particle size of SiOx is reduced from 1.7 μm to less than 200 nm by ball milling, its initial specific capacity and reversible specific capacity can be significantly improved. The deposited Cu/Ni contents of bm-SiOx/(Cu,Ni) can be controlled by adjusting the concentration of Cu2+/Ni2+ in the plating solution. Both bm-SiOx/Cu and bm-SiOx/Ni can improve the initial discharge specific capacity, cycling stability, and rate performance. Bm-SiOx/Cu with a Cu content of 4.76% and bm-SiOx/Ni with a Ni content of 4.29% have the best electrochemical performance. Compared with bm-SiOx/Cu (4.76%), bm-SiOx/Ni (4.29%) has better electrochemical performance; at 0.1C rate, its initial discharge specific capacity can be achieved 2199 mAh/g. After 50 cycles, its reversible specific capacity is 1339 mAh/g.