碳包覆氧化亚硅负极材料中界面特性的影响及其性能优化

Effects and performance optimization of interface characteristics in carbon-coated silica anode materials

摘要

随着手机、电动汽车等移动电子设备的大规模应用，其内置电源锂离子电池的研究日益受到关注，而氧化硅(SiO_x)作为一种有潜力的锂离子电池负极材料，由于其高的锂储能能力和优良的循环稳定性而受到广泛关注。为了进一步提升电池的性能，利用碳材料包覆技术对氧化亚硅负极材料进行改性，形成碳包覆氧化亚硅复合材料。研究主要使用一系列物理、化学实验方法研究了碳包覆氧化亚硅负极材料的微观形貌、化学組成、晶体结构以及电化学性能。结果显示，优化碳层厚度和碳层与氧化亚硅的粘附力对锂离子电池的性能有明显的改善效果。具体来说，当碳层厚度适中（含碳量3%）时，比电容能达到最大，同时电池循环稳定性和倍率性能也得到了显著提升；同时，碳层与氧化亚硅之间的强粘附力有助于防止负极材料析出的Li₂O与电解液的反应。研究结果表明，通过优化碳包覆的氧化亚硅负极材料的界面特性，可以进一步提高其性能，作为一种高性能的负极材料有着巨大的应用前景。

Abstract

With the large-scale application of mobile phones, electric vehicles and other mobile electronic devices, the research of its built-in lithium ion battery has been increasingly paid attention to, and silicon oxide (SiO_x), as a potential lithium ion battery cathode material, has attracted wide attention due to its high lithium energy storage capacity and excellent cycle stability. In order to further improve the performance of the battery, the carbon material coating technology is used to modify the silica oxide anode material to form the carbon coated silica oxide composite material. The micromorphology, chemical composition, crystal structure and electrochemical properties by a series of physical and chemical experimental methods. The results showed that optimizing the thickness of carbon layer and the adhesion of carbon layer to silica oxide have significantly improved the performance of lithium-ion batteries. Specifically, when the thickness of the carbon layer is moderate (3% carbon content), the specific capacitance is the maximum, and the battery cycle stability and multiplier performance are significantly improved, and the strong adhesion between the carbon layer and the silicon oxide helps to prevent the reaction of Li₂O precipitated from the cathode material and the electrolyte. The results show that the interface properties of carbon-coated silica oxide anode materials can be further improved, which has great application prospect as a high-performance anode material.

关键词

碳包覆氧化亚硅 / 锂离子电池 / 界面特性优化

Key words

carbon coated silica / lithium ion battery / interface characteristics optimization

参考文献

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