Journal
ACS APPLIED ENERGY MATERIALS
Volume 2, Issue 12, Pages 8878-8884Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsaem.9b01917
Keywords
lithium-ion battery; electrolyte; high concentration; high voltage; SEI film
Funding
- International Science & Technology Cooperation Program of China [2016YFE0102200]
- National Natural Science Foundation of China [51902024]
- National Postdoctoral Program for Innovative Talents of China [BX20180038]
- China Postdoctoral Science Foundation [2019M650014]
- NSAF [U1930113]
- Beijing Natural Science Foundation [L182022]
- National Key R&D Program of China [2017YFB0102000]
Ask authors/readers for more resources
Lithium-ion battery electrolytes are key components contributing to the Li+ transference and the formation of solid electrolyte interface (SEI) film. A high-concentration LiPF6-based EC/DMC electrolyte is employed to investigate the electrochemical performance of layered LiNi0.6Co0.2Mn0.2O2 cathode material at the high voltage of 4.6 V. Cyclic voltammetry tests indicate that the 6.5 M EC/DMC-LiPF6 high-concentration electrolyte enjoys a stronger oxidation resistance compared with 1 M diluted electrolyte. It is indicated that the highest occupied molecular orbital (HOMO) energy of nEC-Li+ and nDMC-Li+ solvation complexes is reduced with the Li+ concentration increase, suggesting that the high Li+ concentration enhances the oxidation resistance of the solvent molecules by the density functional theory (DFT) method. X-ray photoelectron spectroscopy (XPS) tests demonstrate that the SEI film is different from that of the diluted electrolyte on the cathode surface by using the high-concentration electrolyte. The composite cathode of LiNi0.6Co0.2Mn0.2O2 exhibits a 161.3 mAh/g reversible capacity at the rate of 0.2C (1C = 180 mA g(-1)) after 100 cycles by using the high-concentration electrolyte, while a 138.6 mAh/g lower capacity is exhibited in the diluted electrolyte. The improvement of cycling performance should be attributed to the prevention of the interface side reactions on the cathode.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available