Fluorine-arsenic electrolytes

Comparison of the elemental depth profiles of the SEI (Figure 22) shows that, as with the LiPF electrolyte, the SEI formed on soft carbon is thinner. After 10 minutes of sputtering, the carbon concentration from the underlying HOPG approaches 80%, while for the hard carbon it does not exceed 30%. Eithium content remains relatively constant during sputtering, whereas the concentrations of carbon, oxygen, fluorine, and arsenic decrease monotonically. 

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