Influence of fluoroethylene carbonate on the solid electrolyte interphase of silicon anode for Li-ion batteries: A scanning force spectroscopy study

Zheng Jieyun¹, Liu Jialiang², Wang Suijun², Luo Fei¹, Ben Liubin¹, Li Hong^{1, †}

Three-dimensional plots (a)–(d) for samples 2–5 (discharged to 0.05 V, 0.005 V, 0.005 V and kept at 0.005 V for 48 h, charged to 2 V; EC-based electrolyte, RT), (e)–(i) for samples 6–10 (discharged to 0.2 V 0.05 V, 0.005 V, 0.005 V and kept at 0.005 V for 48 h, charged to 2 V; FEC-based electrolyte, RT), (j)–(k) for samples 11–12 (red arrow, discharged to 0.005 V and kept at 0.005 V for 48 h, charged to 2 V; FEC-based electrolyte, 55 °C), Black substrates are for Li–Si alloy, x, y axes are the coordinates of the SEI film and z axis is the thickness of the SEI film. The color bar of 0–4 GPa is the Young’s modulus for the SEI films.