锂离子电池三维多孔Cu6Sn5合金负极材料的制备及其性能

以三维多孔泡沫铜为基底, 通过直接电沉积的方法制备锂离子电池Cu6Sn5合金负极材料. 发现合金表面大量的微孔和“小岛”不仅增大电极的表面积, 而且显著缓解充放电过程中的体积变化. 测得三维多孔Cu6Sn5合金的初始放电(嵌锂)容量为620 mAh·g-1, 充电(脱锂)容量为560 mAh·g-1, 库仑效率达到90.3%, 具有较好的循环性能. 扫描电子显微镜(SEM)结果显示, 在泡沫铜基底上制备的Cu6Sn5合金电极具有比通常的铜片基底更好的结构稳定性, 经过50 周充放电循环后无明显的脱落现象.

Three-dimensional Porous Cu6Sn5 Alloy Anodes for Lithium-ion Batteries

Three-dimensional porous Cu6Sn5 alloy electrodes were prepared by electroplating using copper foam as current collector. The micro-holes and small islands on surface of the Cu6Sn5 alloy increased largely the surface area of the electrode, and improved significantly the ability of the electrode in buffering the volume change in process of charge/discharge when the Cu6Sn5 alloy was employed as anode in a lithium-ion battery. Galvonostatic charging/discharging results demonstrated that the initial discharge (lithiation) and charge (delithiation) specific capacities of the Cu6Sn5 alloy electrode were 620 mAh·g-1 and 560 mAh·g-1, respectively. It demonstrated that the Cu6Sn5 alloy electrode exhibited a large initial coulomb efficiency (90.3%) and good capacity retention. SEM (scanning electron microscope) results illustrated that the Cu6Sn5 alloy deposited on copper foam substrate was more stable than that on a conventional copper substrate, and displayed no obvious exfoliation after 50 charge/discharge cycles.