中文摘要：

采用恒流充放电、循环伏安（CV）和交流阻抗（EIS）测试方法研究四氟硼酸四乙基铵（Et4NBF4）作为锂离子电池电解液添加剂对石墨负极材料界面性质的影响,通过傅里叶变换红外光谱（FTIR）对固体电解质界面膜（SEI）的成分变化进行分析。结果表明：添加剂Et4NBF4参与了SEI膜的形成,提高了人造石墨（AG）/Li半电池充电容量和后续的循环效率,但是降低了首次充放电效率;首次放电过程中1.0～0.5 V是SEI膜形成和生长的电位区间,而0.5 V以下SEI膜进行不断的修复;添加少量Et4NBF4降低了SEI膜阻抗,提高了电解液与石墨负极的相容性。

英文摘要：

The effect of tetraethylammonium tetrafluoroborate（Et4NBF4） on the graphite interface performance of lithium ion battery in carbonate-based electrolytes was studied by constant current charge-discharge test,cyclic voltammetry（CV）,electrochemical impedance spectroscopy（EIS）,as well as the Fourier transform infra-red（FTIR） spectroscopy.The results indicate that the charge capacity and following cycle efficiency are improved while the initial charge-discharge efficiency is reduced by adding Et4NBF4 because Et4NBF4 participates in forming SEI film.SEI film forms in the potential range of 1.0-0.5 V during the initial discharge,and repairs below 0.5 V.The impedance of SEI film is reduced by adding Et4NBF4.Et4NBF4 additive can effectively improve the compatibility between electrolyte and graphite anode.