Fluorine-Free Lithium Metal Batteries with a Stable LiF-Free Solid Electrolyte Interphase

Abstract

Lithium fluoride (LiF), generated by the decomposition of fluoride in lithium metal batteries (LMBs), is considered an essential component for stabilizing metallic Li. However, the substantial introduction of fluorine in batteries raises potential environmental concerns. In this study, we designed a fluorine-free LMB by integrating a fluorine-free electrolyte and a fluorine-free binder to construct a B/O/ N hybrid solid electrolyte interphase (SEI) capable of providing good stability and fast Li + transport ability. At a test temperature of 60 °C, the LiF-free SEI can achieve a highly reversible Li plating/stripping efficiency, with a Coulombic efficiency of 98.8% under conditions of 3 mA cm −2 and 3 mAh cm −2 . Furthermore, the F-free LMB battery exhibits a rapid charging/discharging rate of 100 C with a capacity exceeding 80 mAh g −1 and demonstrates stable cycling performance over 500 cycles at 50 C. The fast-charging capability was further verified in practical Li−LiFePO 4 full cells.

A bifunctional surfactant-like electrolyte additive for a stable lithium metal anode

“…S6a and b, ESI†), the activation energy of Li + transport process ( E a1 ) and Li + de-solvation process ( E a2 ) is obtained. 28 Based on Arrhenius equation, E a1 and E a2 are slightly smaller than BE in BE + NtF, indicating that BE + NtF presents a stable SEI layer with a low energy barrier, which is conducive to Li + transport and de-solvation (Fig. S6c and d, ESI†).…”

Stable cyclic ether as an electrolyte additive for high-performance lithium metal batteries

“…S3, ESI†). 27 Besides, the introduction of DOL and 4-Me DOL had no significant effect on the bulk conductivity of BE due to the low amount of additives (Fig. S4, ESI†).…”