中空硅纳米球锂离子电池负极材料的制备及电化学性能

Synthesis of Hollow Si Nanospheres and Its Electrochemical Performances as Anode Material for Lithium-ion Batteries

采用直流电弧等离子体蒸发法原位合成了Si-Al纳米颗粒(Si-AlNPs),获得了由晶体Si包覆单晶金属Al核的纳米胶囊结构。通过化学酸洗处理去除Al核制备出中空结构的Si纳米球(Si HNSs),并将其作为锂离子电池的负极材料,研究了电极的循环和倍率电化学性能。与Si-AlNPs电极相比,Si HNSs电极的循环稳定性及倍率性能都显著提高,这源于中空结构的Si纳米球为嵌/脱锂过程中的体积变化提供了有效缓冲空间,同时也为锂离子迁移提供了更多通道。

Si-Al nanoparticles（Si-AlNPs）possessed the nanocapsule structure with crystal Si shell and monocrystal Al core were prepared by DC arc-discharge plasma method.The hollow Si nanospheres（Si HNSs）were successfully obtained by subsequently removing the Al component from Si-AlNPs through acid pickling process.Both of Si-AlNPs and Si HNSs were investigated as the anode materials for lithium ion battery.The results indicated that electrochemical performances of Si HNSs electrode had been greatly improved compared with Si-AlNPs electrode,because the hollow space in Si nanosphere could provide an effective buffer space for volume change during the intercalation/deintercalation of lithium ions and supplies more migration channels for lithium ions.