Improved electrochemical performance of Cu-Sn/nano-SiO2 composite anode materials for lithium-ion batteries fabricated by controlled electrodeposition

Abstract

Cu-Sn/nano-SiO₂ composite materials are fabricated through electrodeposition process coupled with precise thermal treatment, which employs hexadecyl trimethyl ammonium bromide to guarantee the even distribution of nano-SiO₂ particles within the Cu-Sn alloy framework. The characterization results indicate that integrating nano-SiO₂ into the Cu-Sn matrix effectively prevents active particles from detaching from the copper foil current collector. By adjusting the current density, the electrochemical performance of the Cu-Sn/nano-SiO₂ composite electrode is significantly enhanced. Specifically, the initial charge and discharge specific capacities of the composite electrolyte are approximately 746.6 and 1470.8 mAh/g at 100 mA/g, respectively. Moreover, the cell can still maintain a discharge specific capacity of 358.6 mAh/g after 100 cycles. Furthermore, the cell demonstrates an improved lithium-ion diffusion coefficient of approximately 9.639 × 10^–15 cm²/s and a lower transfer resistance of 54.65 Ω. Therefore, a direct approach of fabricating the Cu-Sn/nano-SiO₂ composite electrode with enhanced electrochemical properties may provide valuable guidance for alloy anodes in the energy storage field.