钠离子电池硬碳负极材料首周效率的研究进展

摘要

Sodium ion battery has advantages of abundant original materials,low costs and so on and its commercial applica-tion depends on development of its cathode and anode materials while the anode materials are critical components. In nu-merous anode materials,hard carbon has advantages of appropriate sodiation potential,high capacity,long cycle life and good rate capability as well as plentiful original materials and simple preparation,it is regarded as the most likely anode ma-terial of sodium ion battery for realizing commercial application.But the low initial coulombic efficiency of hard carbon seri-ously affects its application in full cell battery.Therefore,this paper summarizes and analyzes the research progress of hard carbon in aspects of the influence of initial coulombic efficiency on full cell battery,the influencing factors and improvement methods of the initial coulombic efficiency.The paper points out it is able to effectively improve initial coulombic efficiency by reducing specific surface area,increasing synthesis temperature,reducing surface functional groups and regulating electro-lyte composition.Corresponding analysis indicates further understanding of initial coulombic efficiency is beneficial to devel-op high capacity and high efficiency hard carbon material and promote the commercial application of sodium ion battery.%钠离子电池具有原材料丰富和成本低廉等优点,其商业化应用主要取决于正负极材料的发展,其中负极材料是关键组成部分.在众多负极材料当中,硬碳负极材料由于具有嵌钠电位合适、容量较高、循环寿命长、倍率性能好以及原材料丰富、制备简单等优点,被认为是最有可能首先实现商业化应用的钠离子电池负极材料.但硬碳负极的首周库伦效率较低,这严重影响了其在全电池中的应用.针对此,从首周库伦效率对全电池性能的影响、首周库伦效率的影响因素以及改善方法等几方面对硬碳负极材料的研究进展进行总结和分析,指出降低比表面积、提高合成温度、减少表面官能团和调节电解液组分,可以有效提高首周库伦效率.分析表明对首周库伦效率的进一步理解有利于开发高容量、高效率的硬碳材料并促进钠离子电池的商业化应用.