中国物理B ›› 2023, Vol. 32 ›› Issue (7): 78201-078201.doi: 10.1088/1674-1056/accd51
A novel calculation strategy for optimized prediction of the reduction of electrochemical window at anode
Guochen Sun(孙国宸)1,2, Jian Gao(高健)3,†, and Hong Li(李泓)1,‡
- 1 Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
2 College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China;
3 College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
A novel calculation strategy for optimized prediction of the reduction of electrochemical window at anode
Guochen Sun(孙国宸)1,2, Jian Gao(高健)3,†, and Hong Li(李泓)1,‡
- 1 Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
2 College of Materials Sciences and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China;
3 College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
摘要： The reduction of the electrochemical window (EW) of electrolytes plays a significant role in assessing their compatibility with the anode in lithium-ion batteries. However, the accurate calculation of the reduction of EW is still challenging due to missing the solvation effects, condensation effects, kinetic factors, and the passivation on anodes. The theoretical prediction of the intrinsic and apparent EW is confirmed by a comprehensive experimental analysis of ethylene carbonate-dimethyl carbonate (EC-DMC) electrolytes, combining linear sweep voltammetry (LSV) and gas chromatography-mass spectrometry (GC-MS). The proposed novel kinetic normal distribution theory model can quantitatively explain the current density from LSV and affirm acetaldehyde (MeCHO) as one of the primary reduction products of EC. The solvent effect restricts the intrinsic EW of EC-DMC without lithium salt to 2.6 V (vs. Li+/Li) arising from the Marcus-Gerischer theory and the passivation of MeCHO on the anode broadens the apparent EW to 0.3 V (vs. Li+/Li) arising from the normal distribution of the lowest unoccupied molecular orbital (LUMO) for MeCHO produced by thermal motion. In addition, the passivation on the anode depends intensively on the lithium salt, resulting in more complicated influences on the apparent EW.
中图分类号: (Lithium-ion batteries)
- 82.47.Aa