Fig. 2: Electrochemical stability and interfacial investigation of PDOL-based electrolytes with Li-metal negative electrodes.

a Cycling performance of Li||Li symmetric cells at 1 mA cm⁻² and 1 mAh cm⁻², and corresponding b plating/stripping profiles at various cycles. c Coulombic efficiency (CE) and d voltage profiles of Li||Cu cells with various PDOL-based electrolytes at 0.5 mA cm⁻² and 0.5 mAh cm⁻². e XPS F 1s spectra of cycled Li metal with different PDOL-based electrolytes before and after Ar-ion sputtering. f ToF-SIMS corresponding depth profiles of LiF₂⁻ and TFSI⁻ for cycled Li metal with Zn-PDOL and Zn-IBPE electrolytes (inset: 3D reconstruction of TFSI⁻ species). The intensity of these spectra was shown in arbitrary unit (a.u.). SEM and digital images of cycled Li metal with g Zn-PDOL, h PDOL-CTA, and i Zn-IBPE electrolytes collected from Li||Li symmetric cells after 100 cycles.