Moreover, the chemical environment of DME molecules, a frequently mentioned issue in electrolyte design, is also examined by nuclear magnetic resonance (NMR) spectroscopy. At 1 M LiTFSI electrolyte, the peak of ODME shifts upfield with the increase of LiNO3 concentration (Figure ). However, this upfield shift was weakly indistinguishable when only 50 mM LiNO3 was added, suggesting a weakly changed chemical environment of DME in the bulk electrolyte. Even when the concentration of LiNO3 increases to 200 mM, this upfield shift remains unnoticeable. Such phenomenon is further confirmed by molecular dynamics (MD) simulations of bulk ether electrolytes, where the number density of DME around Li + is slightly changed when adding 50 mM LiNO3 and almost unchanged with LiNO3 concentration increasing from 50 mM to 200 mM (Figure ). The detailed coordination states are represented in Figure and 2F, and Figure , where NO3 -partly replaces TFSI -anion but the coordination between Li + and DME is maintained. Until the LiNO3 concentration reaches 500 mM, the replacement of DME by NO3 -in the first solvation shell takes place (Figure ). These results demonstrate a slight change of electrolyte ion solvation with additive, which also fails to explain the great improvement of oxidation stability.