预锂化在SiO_(x)@C负极材料中的应用研究  

Application of prelithiation in SiO_x@C anode material

作　　者：张正裕 白哲 何洁龙 吴佳霓 蓝利芳 李军[1] Zhang Zhengyu;Bai Zhe;He Jielong;Wu Jiani;Lan Lifang;Li Jun(School of Light Industry and Chemical Engineering,Guangdong University of Technology,Guangzhou 510006)

机构地区：[1]广东工业大学轻工化工学院,广州510006

出　　处：《化工新型材料》2023年第4期170-174,共5页New Chemical Materials

基　　金：佛山市科技计划项目(1920001001421)。

摘　　要：通过正硅酸乙酯水解、蔗糖热解包覆制备了锂离子电池SiO_(x)@C负极材料。为了减少SiO_(x)@C在首次循环中的不可逆容量损失,采用SiO_(x)@C与金属锂片直接接触的方法对其进行预锂化,考察了不同预锂化处理时间对材料电化学性能的影响,研究了预锂化处理前后材料表面形貌和组成成分的变化,分析了预锂化处理在材料中的作用机理。结果表明,预锂化处理3min后,SiO_(x)@C的首次库伦效率已达到99.2%,高于未预锂化的63.9%,而且仍然表现出较高的循环稳定性。通过SEM、XPS、容量微分曲线、交流阻抗谱等分析,发现预锂化处理过程中SiO_(x)@C已发生不可逆转化反应,并在材料表面形成了SEI膜,从而达到减少首次循环中不可逆容量损失的目的。SiO_(x)@C anode material for lithium-ion batteries was prepared by hydrolysis of ethyl orthosilicate and pyrolysis of sucrose.In order to reduce irreversible capacity loss of the SiO_(x)@C in the first cycle,we used the method of direct contact between the SiO_(x)@C@C and the metal lithium sheet to achieve the purpose of prelithiation.The influence of different prelithiation treatment time on the electrochemical performance of SiO_(x)@C@C was investigated.The changes of the surface morphology and composition of SiO_(x)@C@C before and after prelithiation were studied.The mechanism of prelithiation in SiO_(x)@C was analyzed.The results indicated that the initial Coulombic efficiency of the SiO_(x)@C with a prelithiation treatment of 3min reached 99.2%,which was much higher than the 63.9%of the SiO_(x)@C without prelithiation.The prelithiated SiO_(x)@C also exhibited high cycle stability.SEM,XPS,dQ/dV curves,EIS analyses showed that the SiO_(x)@C had undergone an irreversible conversion reaction and formed SEI film on its surface during prelithiation process,thereby achieving the purpose of reducing the irreversible capacity loss in the first cycle.

关 键 词：锂离子电池 SiO_(x)@C负极材料 预锂化 不可逆容量 首次库伦效率 

分 类 号：TM912.9[电气工程—电力电子与电力传动]