物理化学学报2009，Vol.25Issue(5)：905-910,6.
新型锂盐LiBC2O4F2在EC+DMC溶剂中的电化学行为
Electrochemical Behaviors of New Lithium Salt LiBC2O4F2 in EC+DMC Solvents
摘要
Abstract
The thermal stability of lithium difluoro(axalato)borate (LiODFB)was analyzed by thermal gravimetric-differential thermal analysis (TG-DTA).The electrochemical performance and interfacial characteristics of the LiODFB/ethylene carbonate(EC)+dimethyl carbonate(DMC)electrolyte were studied by constant current charge-discharge and electrochemical impedance spectroscopy(EIS).Results show that LiODFB has higher thermal stability and that the lithium-ion cells using LiODFB salt in EC+DMC solvents exhibit excellent electrochemical performances.Compared with the LiPF6/EC+DMC electrolyte,the lithium-ion cells using LiODFB-based electrolyte have very good capacity retention at 55℃.At 0.5C and 1C(1C=250 mA·g-1)discharge rates,the difference between the rate capability of the two cells is tiny.LiODFB iS reduced at about 1.5 V(vs Li/Li+) and forms a robust protective solid electrolyte interphase (SEI)film on the graphite surface.EIS tests show that these lithium-ion batteries which use the LiODFB-based electrolyte have a slightly higher interfacial impedance.Therefore,as a new salt,LiODFB is a promising alternative lithium salt for the replacement of LiPF6 in lithium ion battery electrolytes.关键词
锂离子电池/电解液/二氟草酸硼酸锂/电化学性能/界面特性Key words
Lithium-ion battery/Electrolyte/Lithium difluoro(axalato)borate/Electrochemical performance/Interfacial property分类
化学化工引用本文复制引用
高宏权,赖延清,张治安,刘业翔..新型锂盐LiBC2O4F2在EC+DMC溶剂中的电化学行为[J].物理化学学报,2009,25(5):905-910,6.基金项目
国家科技支撑计划(2007BAE12B01)及国家自然科学基金项目(20803095)资助 （2007BAE12B01）
