F127/纤维素复合固态电解质的双锂盐调控与电池性能研究OA

To address the poor interfacial stability between polyether-based solid electrolytes and lithium metal anodes,this study adopted a dual-salt strategy to design and prepare an F127/cellulose composite solid electrolyte.A homogeneous polymer slurry was fabricated by blending a LiTFSI and LiDFOB dual-salt system with F127 using a hot-melting method,which was then infiltrated into a porous cellulose membrane to obtain a structurally dense composite electrolyte.The results indicate that the introduction of LiDFOB significantly improves the electrolyte/lithium metal interface performance and promotes the formation of a stable solid electrolyte interphase(SEI)layer.Electrochemical tests reveal that the dual-salt electrolyte achieves an ionic conductivity of 2.0×10-4 S·cm-1 at 60℃and an enhanced lithium-ion transference number of 0.31.Li/Li symmetric cells assembled with this electrolyte exhibit an increased limiting current density of 0.5 mA·cm-2 and maintain stable cycling for over 2 000 h under the conditions of 0.1 mA·cm-2 and 0.1 mAh·cm-2.LFP/Li full cells deliver a discharge capacity of 111.11 mAh·g-1 at a 2.0 C rate,with a capacity retention of 66.38%after 800 cycles at 0.5 C.This work provides a simple and feasible dual-salt strategy that synergistically enhances ionic conductivity and interfacial stability of the electrolyte,offering new insights for the design of electrolytes for high-energy-density solid-state lithium metal batteries.