2-(Trifluoroacetyl) thiophene as an electrolyte additive for high-voltage lithium-ion batteries using LiCoO2 cathode. (15th October 2020)

• Record Type: Journal Article
• Authors: Sun, Yi; Huang, Jian; Xiang, Hongfa; Liang, Xin; Feng, Yuezhan; Yu, Yan
• Is Part Of: Journal of materials science & technology. Volume 55(2020)
• Page Start: 198
• Page End: 202
• Publication Date: 2020-10-15
• Subjects: Lithium ion batteries -- Electrolyte additive -- High voltage -- Thiophene; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2019.11.002
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: The 2-(Trifluoroacetyl) thiophene (TFPN) has been developed as a functional electrolyte additive. Introduction of 0.5 wt% TFPN into the electrolyte can greatly enhance the cycling performance of high-voltage LiCoO2 cathode. Addition of 0.5 wt% TFPN can effectively suppress the decomposition of both electrolyte solvent and lithium salt. Abstract: The development of high voltage electrolytes plays a critical role to achieve advanced lithium ion batteries with high energy density. Application of suitable electrolyte additives is a facile and effective way to achieve enhanced electrochemical performance at high voltage operation. In this work, 2-(trifluoroacetyl) thiophene (TFPN) was investigated as a functional electrolyte additive for high performance lithium ion batteries using high-voltage LiCoO2 cathode. When cycled between 3.0 V and 4.4 V at 0.5 C, the capacity retention of the LiCoO2 cathode significantly increases from 33.2 %–90.6 % by the addition of 0.5 wt% TFPN into the baseline electrolyte. Based on the measurements on impedance spectra and X-ray photoelectron spectra, the improved cycling performance is attributed to the preferential oxidation of TFPN on the cathode surface and thus form a protective layer to suppress the decomposition of both electrolyte solvent and lithium salt. This work presents that TFPN has great potential as functional additive for the development of high-voltage and high-energy-density lithium ion batteries.