Acta Phys. -Chim. Sin. ›› 2009, Vol. 25 ›› Issue (10): 1967-1971.doi: 10.3866/PKU.WHXB20090932

• ARTICLE • Previous Articles     Next Articles

Film Formation and Cycleability of LiBOB-Based Electrolyte

TAN Xiao-Lan, CHENG Xin-Qun, MA Yu-Lin, ZUO Peng-Jian, YIN Ge-Ping   

  1. College of Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
  • Received:2009-04-09 Revised:2009-06-09 Published:2009-09-29
  • Contact: YIN Ge-Ping E-mail:yingphit@hit.edu.cn

Abstract:

The formation of solid electrolyte interphase (SEI) filmon graphite in a lithiumbis(oxalato)borate (LiBOB)-based electrolyte was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The effects of SEI filmon the cycleabilities of graphite were examined at roomtemperature (25 ℃) and at high temperature (70 ℃). Results showed that the SEI filmwas formed at around 1.7 V and BOB- ions were reduced to oxalate, which was one of the components of the SEI film. EIS showed that the impedance of the SEI film decreased during the charge/discharge cycle and this was favorable for cycle stability. Whether it was at room temperature or at high temperature, the graphite had better cycleability in the LiBOB-based electrolyte than in the LiPF6-based electrolyte.

Key words: Li-ion battery, Electrolyte, LiBOB, SEI film

MSC2000: 

  • O646