高容量硅基纳米电缆结构锂离子电池负极材料的可控制备与性能研究

项目名称： 高容量硅基纳米电缆结构锂离子电池负极材料的可控制备与性能研究

项目编号： No.21303064

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 曹菲菲

作者单位： 华中农业大学

项目金额： 26万元

中文摘要： 硅是非常有前途的锂离子电池负极材料，但其在电化学循环过程中会经历巨大的体积变化导致容量迅速衰减，如何限制其体积膨胀、收缩和稳定其表面，以保持较高的储锂容量，是目前国际上的热点研究课题。本项目从结构设计的角度出发，通过湿化学法制备具有纳米电缆结构（以碳纳米管、碳纤维等为导电内核）和电化学惰性保护层（氧化铝、氧化硅等）包覆的C-Si复合电极材料。研究和探索锂离子、电子在C-Si纳米电缆中的输运与存储特性，考察C-Si纳米电缆及Al2O3等修饰后的C-Si纳米电缆作为锂离子电池负极材料的循环性能和倍率性能。确立一种基于湿化学法的制备具有高容量硅基锂离子电池负极材料的新方法，揭示纳米电缆结构和表面包覆在改进硅的电化学性能方面所起的主要作用，为硅基锂离子电池负极材料的结构设计和性能提升提供理论参考。本项目的实施对制备轻便、安全、廉价、环境友好的锂离子电池具有重要的实际意义。

中文关键词： 硅；碳；谷壳；钠-微分级结构；负极

英文摘要： Silicon is a promising anode material for Li-ion battery. The main disadvantage that restricts its application is that high-capacity Si anode shows large volume change during Li+ insertion and extraction, which causes the structure collapse leading to rapid loss of capacity upon cycling. Many attentions have been paid on how to strain the volume change and matain stable surface of Si. In this work, we start from the viewpoint of structure design and aim to synthesize C-Si composite electrode material with nanocable structure combined with the advantage of thin electrochemical inert layer coating. The synthetic approach is the wet-chemical method which is cheap and proper for large-scale production. Further research is performed on the transportation and storage of lithium ions and electrons in C-Si nanocables. The electrochmeical performances of these C-Si nanocables such as cycling stability and rate performance are also tested. These researches could help establishing a reliable pathway to produce silicon-based anode materials for LIBs with high capacity, uncovering the functions of nanocable structure and surface coating in the improvement of the electrochemical performances of Si, as well as providing useful information for the design and synthesis of silicon-based electrode materials. The development of po

英文关键词： silicon；carbon；rice husk；nano/micro hierarchical structure；anode