Scholarlink

<p>Silicon/expanded graphite (Si/EG) composites with nano-silicon-to-EG mass ratios of 1:2 (sample 1) and 1:1 (sample 2) were fabricated via freeze-drying and high-temperature vacuum heat treatment. The nano-silicon was loaded onto the surface of expanded graphite (EG) through the organic cracking of carbon. Initial charge capacity values of 922.9&#xa0;mAh/g and 1269.9&#xa0;mAh/g were obtained for sample 1 and sample 2, with initial coulombic efficiency of 78.45% and 79.83%, respectively, while the pure nano-silicon sample was only 49.81%. The reversible capacity after 260 cycles for sample 1 and sample 2 was 526.9&#xa0;mAh/g and 920.8&#xa0;mAh/g, with capacity retention ratios of 57.09% and 72.51%, respectively. Moreover, the cycling stability of sample 2 was found to be superior to that of sample 1 due to a more uniform distribution of higher silicon loading on the EG surface, which facilitates the formation of a stable solid electrolyte interface (SEI) film rich in LiF components. The incorporation of EG significantly improves the electrical conductivity and rate capability of silicon-based materials. The Si/EG composite demonstrates excellent high-rate charge/discharge ability due to excellent electrochemical kinetic performance. At current density of 1 A/g, the capacity of sample 1 and sample 2 reached 748.7&#xa0;mAh/g and 1038.7&#xa0;mAh/g, with capacity retention rates of 79.7% and 80.2%, respectively. Thus, the design of mass ratios for nano-silicon and EG is critical for obtaining a Si/EG composite with excellent cycle stability and high-rate performance.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Expanded Graphite Supported Nano-silicon Composite for High-Performance Anode Materials in Lithium-ion Batteries

  • 期刊论文

  • 发表日期：

    2025年12月10日

查看全文
  • Weichao Zhang,
  • Wenping Liu,
  • Xiaoxu Lei,
  • Huarui Xu,
  • Guisheng Zhu,
  • Yunyun Zhao,
  • Ying Luo,
  • Kunpeng Jiang

摘要

Silicon/expanded graphite (Si/EG) composites with nano-silicon-to-EG mass ratios of 1:2 (sample 1) and 1:1 (sample 2) were fabricated via freeze-drying and high-temperature vacuum heat treatment. The nano-silicon was loaded onto the surface of expanded graphite (EG) through the organic cracking of carbon. Initial charge capacity values of 922.9 mAh/g and 1269.9 mAh/g were obtained for sample 1 and sample 2, with initial coulombic efficiency of 78.45% and 79.83%, respectively, while the pure nano-silicon sample was only 49.81%. The reversible capacity after 260 cycles for sample 1 and sample 2 was 526.9 mAh/g and 920.8 mAh/g, with capacity retention ratios of 57.09% and 72.51%, respectively. Moreover, the cycling stability of sample 2 was found to be superior to that of sample 1 due to a more uniform distribution of higher silicon loading on the EG surface, which facilitates the formation of a stable solid electrolyte interface (SEI) film rich in LiF components. The incorporation of EG significantly improves the electrical conductivity and rate capability of silicon-based materials. The Si/EG composite demonstrates excellent high-rate charge/discharge ability due to excellent electrochemical kinetic performance. At current density of 1 A/g, the capacity of sample 1 and sample 2 reached 748.7 mAh/g and 1038.7 mAh/g, with capacity retention rates of 79.7% and 80.2%, respectively. Thus, the design of mass ratios for nano-silicon and EG is critical for obtaining a Si/EG composite with excellent cycle stability and high-rate performance.