硅氧负极材料包覆工艺对电池性能的研究

Research on coating process of silicon oxide anode material

为提高电池能量密度,需要使用高容量的硅-石墨混合负极材料。通过改变硅负极材料制备工艺,采用CVD法包覆及沥青包覆对硅负极表面进行碳包覆,并对材料进行物性测试、极片测试及电化学性能分析。结果表明:通过气相CVD法包覆的碳层包覆完整,体现出“绒状”结构的负极材料,其极片测试及电池的循环性能更为优异。在0.5 C充/1 C放制式下经过800次循环,容量保持率达到73.9%,循环性能优于沥青包覆的负极材料性能。

In order to improve the energy density of the battery,it is necessary to use high-capacity silicon-graphite mixed negative materials in negative electrode selection.By changing the preparation process of silicon negative electrode materials,CVD coating and asphalt coating were used to coat the surface of silicon negative electrode with carbon,and physical property testing,electrode testing,and electrochemical performance analysis was conducted on the material.The results show that the carbon layer coated by the gas phase CVD method is completed,reflecting the“velvet”structure of negative electrode material,and the electrode sheet test and cycle performance is more excellent.After 800 cycles under the 0.5 C charging/1 C discharge system,the capacity retention rate can reach 73.9%,and the cycle performance is significantly better than that of the asphalt coated negative electrode material.