Tris(trimethylsilyl) borate as an electrolyte additive for high-voltage lithium-ion batteries using LiNi 1/3 Mn 1/3 Co 1/3 O 2 cathode

Chunfeng Yan, Ying Xu, Jianrong Xia, Cuiran Gong, Kerong Chen
2016 Journal of Energy Chemistry  
The influence of tris(trimethylsilyl) borate (TMSB) as an electrolyte additive on lithium ion cells have been studied using Li/LiCo 1/3 Ni 1/3 Mn 1/3 O 2 cells at a higher voltage, 4.7 V versus Li/Li + . 1 wt% TMSB can dramatically reduce the capacity fading that occurs during cycling at room temperature (RT) and elevated temperature (60 °C). After 150 cycles at 1 C rate (1 C = 278 mAh/g), the capacity retention of Li/LiCo 1/3 Ni 1/3 Mn 1/3 O 2 is up to near 72% in the electrolyte with TMSB
more » ... d, while it is only about 35% in the baseline electrolyte. The electrochemical behaviors, the surface chemistry and structure of Li/LiCo 1/3 Ni 1/3 Mn 1/3 O 2 cathode are characterized with charge/discharge test, linear sweep voltammetry (LSV), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), thermal gravimetric analyses (TGA), scanning electron microscope (SEM) and transmission electron microscopy (TEM). These analysis results reveal that the addition of TMSB is able to protectively modify the electrode CEI film in a manner that suppresses electrolyte decomposition and degradation of electrode surface structure, even though at both a higher voltage of 4.7 V and an elevated temperature of 60 °C.
doi:10.1016/j.jechem.2016.04.010 fatcat:amtthci4efgxdd5b2utnhbwwh4