High power and stable P-doped yolk-shell structured Si@C anode simultaneously enhancing conductivity and Li+ diffusion kinetics

• 作者: Ming Chen Qinnan Zhou Jiantao Zai Asma Iqbal TsegayeTadesse Tsega Boxu Dong Xuejiao Liu Yuchi Zhang Changyu Yan Liang Zhao Ali Nazakat SharelPeisan E CheeTongJohn Low Xuefeng Qian
• 来源期刊: 纳米研究（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: Research Articles
• 页码范围: 1004-1011
• 页数: 8页
• 语种: 英文

摘要

Silicon is a low price and high capacity anode material for lithium-ion batteries.The yolk-shell structure can effectively accommodate Si expansion to improve stability.However,the limited rate performance of Si anodes can't meet people's growing demand for high power density.Herein,the phosphorus-doped yolk-shell Si@C materials (P-doped Si@C) were prepared through carbon coating on P-doped Si/SiOx matrix to obtain high power and stable devices.Therefore,the as-prepared P-doped Si@C electrodes delivered a rapid increase in Coulombic efficiency from 74.4％ to 99.6％ after only 6 cycles,high capacity retention of ～ 95％ over 800 cycles at 4 A·g-1,and great rate capability (510 mAh·g-1 at 35 A·g-1).As a result,P-doped Si@C anodes paired with commercial activated carbon and LiFePO4 cathode to assemble lithium-ion capacitor (high power density of ～ 61,080 W·kg-1 at 20 A·g-1) and lithium-ion full cell (good rate performance with 68.3 mAh·g-1 at 5 C),respectively.This work can provide an effective way to further improve power density and stability for energy storage devices.