Influence of fluoroethylene carbonate as co-solvent on the high-voltage performance of LiNi1/3Co1/3Mn1/3O2 cathode for lithium-ion batteries

• DOI: 10.1016/j.electacta.2016.01.032
• Publication Date: 2016-01-07T02:30:31Z
• Authors: Long Wang; Yulin Ma; Yunteng Qu; Xinqun Cheng; Pengjian Zuo; Chunyu Du; Yunzhi Gao; Geping Yin
• Keywords: 01 natural sciences; 7. Clean energy; 0104 chemical sciences; 3. Good health

Abstract In this work, the electrochemical performance of LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode is investigated under high voltage with fluoroethylene carbonate (FEC) as co-solvent for lithium ion battery. Charge/discharge tests show that the cycling and rate performances of LiNi 1/3 Co 1/3 Mn 1/3 O 2 are dramatically improved at high voltage operation when ethylene carbonate (EC) is replaced by FEC in electrolyte solution. After 100 cycles between 3.0 and 4.6 V ( vs. Li/Li + ) at 0.2C rate, the capacity retention of LiNi 1/3 Co 1/3 Mn 1/3 O 2 with FEC/dimethyl carbonate (DMC) (1/4, vol.%) solution is 82.7%, while the EC-containing electrolyte is only 41.3%. The effects of FEC on the high-voltage performance and the surface properties of the LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode are characterized by electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). It is found that FEC as co-solvent participates in the formation of protective surface films on the LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode, which efficiently suppresses the decomposition of the electrolyte, prevents the severe structure destruction and improves the cycling stability and rate capability of LiNi 1/3 Co 1/3 Mn 1/3 O 2 electrode under high voltage.