N‑Allyl‑N,N‑Bis(trimethylsilyl)amine as a Novel Electrolyte
Additive To Enhance the Interfacial Stability of a Ni-Rich Electrode
for Lithium-Ion Batteries
posted on 2018-04-24, 00:00authored byQinfeng Zheng, Lidan Xing, Xuerui Yang, Xiangfeng Li, Changchun Ye, Kang Wang, Qiming Huang, Weishan Li
Enhancing
the electrode/electrolyte interface stability of high-capacity
LiNi0.8Co0.15Al0.05O2 (LNCA)
cathode material is urgently required for its application in next-generation
lithium-ion battery. Herein, we demonstrate that enhanced interfacial
stability of LNCA can be achieved by simply introducing 2 wt % N-allyl-N,N-bis(trimethylsilyl)amine
(NNB) electrolyte additive. Electrolyte oxidation reactions and electrode
structural destruction are greatly suppressed in the electrolyte with
NNB additive, leading to improved cyclic stability of LNCA from 72.8
to 86.2% after 300 cycles. The mechanism of NNB on improving the cyclic
stability of LNCA has been verified to its excellent solid electrolyte
interface (SEI) film-forming capability. Moreover, the X-ray diffraction
and X-ray photoelectron spectroscopy results indicate that the NNB-derived
Si-containing SEI film restrains the Li/Ni disorder of LNCA during
cycling, which further improves the cyclic stability of Ni-rich LNCA.
Importantly, the charging/discharging test reveals that the NNB additive
effectively improves the cyclic stability of the LNCA/graphite full
cell.