硅/金属氧化物复合负极材料研究进展

Research progress of silicon/metal oxide composite anode materials

硅以其脱锂电位(约为0.4 V)低、理论比容量(4200 mAh/g)高、资源丰富和环境友好等优点而被广泛关注,但硅材料在脱嵌锂的过程中存在严重的体积膨胀(>300%),从而导致循环性能差和库伦效率低,以至于阻碍了其实际应用。据报道采用硅和金属氧化物进行复合处理的新策略来制备硅基负极复合材料,可使其电化学性能得到了明显改善。对此分别从金属氧化物对硅进行表面包覆以及与硅发生原位固态反应引进硅化物和金属颗粒的角度,综述了近几年这两方面研究的相关成果,并阐述了用金属氧化物改性硅负极材料尚待解决的问题和未来发展趋势。

Silicon has been widely concerned for its low delithium potential(about 0.4 V),high theoretical specific capacity(4200 mAh/g),abundant resources and environmental friendly.However,silicon materials have serious volume expansion(>300%)in the process of delithium,which leads to poor cyclic performance and low coulomb efficiency,and thus hinders its practical application.It has been reported that the electrochemical properties of silicon-based anode composites have been significantly improved by using a new strategy of composite treatment of silicon and metal oxides.In this paper,the research achievements in recent years are reviewed from the perspectives of coating silicon by metal oxide and introducing silicide and metal particles by in-situ solid-state reaction with silicon,and the problems to be solved and the development trend of modifying silicon anode materials by metal oxide are also described.