A novel double-coated anode material SiOx/C/Cu2O for lithium ion batteries

Silicon monoxide (SiOx, 0 < x < 2) has been one of the new directions of scientific researchers because of some characteristics, such as higher theoretical specific capacity and lower volume expansion efficiency. However, its disadvantages such as the volume expansion effect and poor conductivity still exist in the process of charge and discharge, which limit its commercialization process. In this paper, cuprous oxide and carbon coated silicon monoxide (SiOx/C/Cu2O) composites were obtained by high temperature heat treatment. In the SiOx/C/Cu2O anodes, carbon can buffer the volume expansion of the lithium intercalation, enhance the conductivity of the material, reduce the contact between the electrolyte and the active substance, Cu2O can further reduce the contact between the electrolyte and the active substance, greatly buffer the change of electrode structure and improve the overall cycling performance. After the rate of 0.5C (1C = 2100 mA g-1) for 500 cycles, the discharge specific capacity is 704.0 mAh g-1, about 350 mAh g-1 higher than SiOx, which shows excellent long-cycle ultra -high stability.