Wenna Huang, L. Xing, Yating Wang
Dec 1, 2014
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Influential Citations
86
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Quality indicators
Journal
Journal of Power Sources
Abstract
Abstract In this work, 4-(Trifluoromethyl)-benzonitrile (4-TB) is used as a novel electrolyte additive for LiNi 0.5 Mn 1.5 O 4 cathode of high voltage lithium ion battery. Charge–discharge tests show that the cyclic stability of LiNi 0.5 Mn 1.5 O 4 is significantly improved by using 0.5 wt.% 4-TB. With using 4-TB, LiNi 0.5 Mn 1.5 O 4 delivers an initial capacity of 133 mAh g −1 and maintains 121 mAh g −1 after 300 cycles with a capacity retention of 91%, compared to the 75% of that using base electrolyte (1 M LiPF 6 in ethylene carbonate(EC)/dimethyl carbonate(DMC)). The results from linear sweep voltammetry, density functional theory calculations, electrochemical impedance spectroscopy, scanning electron microscope, energy dispersive spectroscopy, Fourier transform infrared, and inductively coupled plasma, indicate that 4-TB has lower oxidative stability than EC and DMC, and is preferentially oxidized on LiNi 0.5 Mn 1.5 O 4 forming a low-impedance protective film, which prevents the subsequent oxidation decomposition of the electrolyte and suppresses the manganese dissolution from LiNi 0.5 Mn 1.5 O 4 .