锂离子电池硅基负极材料的研究进展

Recent Progress for Silicon-based Anode of Lithium Ion Batteries

硅材料因其具有较高的理论容量、脱/嵌锂电位较低等优势受到人们的广泛关注。但是硅材料在嵌/脱锂过程中剧烈的体积效应限制了其实际应用。剧烈的体积变化将导致电极材料快速机械粉化,并从集流体上逐渐脱离,造成容量的快速下降。同时,还会导致材料表面的固体电解质界面膜(solid electrolyte interface,SEI)不断破坏-重构,造成持续的锂离子损耗。因此这些缺点是硅材料运用于电池负极材料亟需解决的问题。针对上述问题一个很好的解决办法是同具有弹性的导电材料进行复合,由此硅与碳材料的复合成为锂离子电池阳极的理想选择。本文列举了一些改进硅基负极材料的方法,并对一些硅/碳复合负极材料进行了综述,以及提出未来硅碳负极材料发展趋势。

Silicon has attracted much attention in recent years due to its advantages of high specific capacity,and low lithium insertion/deintercalation electric potential.However,the poor electrochemistry performance due to the large volume change of Si upon insertion and extraction of lithium has been an impediment to its deployment.The drastic volume effect will lead to the rapid mechanical pulverization of the electrode material,and gradually break away from the current collector,resulting in a rapid decrease in the capacity of the electrode materials.At the same time,it will also lead to the continuous destruction and reconstruction of the solid electrolyte interface(SEI)film formed on the surface of the material,resulting in continuous lithium ion loss.Therefore,these shortcomings need to be solved urgently.A good solution to the above problems is to combine silicon with some elastic conductive materials,so the composite of silicon and carbon materials is the ideal choice for lithium ion battery anode.In this review,some methods of improving silicon-based anode materials are listed,and some silicon/carbon composite anode materials are reviewed,also the development trend of silicon-carbon anode materials in the future is put forward.