Fluoride Graphdiyne Enhances Polymer Electrolytes Through Regional Electric Potential Synergies for High-Performance...

Solid-state polymer electrolytes (SSPEs) have attracted considerable attention for use in all-solid-state lithium-metal batteries (ASSLMBs). However, their low Li-ion conductivity, small Li-ion transference number, and poor interfacial compatibility hinder their practical application, which may be associated with the uncoordinated interactions between the key components in SSPEs including polymers, lithium salts, and nanofillers. In this study, fluoride graphdiyne (FGDY) is used as a nanofiller to enhance the overall performance of PVDF-HFP/LiTFSI in ASSLMBs through regional electric potential synergies (REPS), which refers to the proper interaction between particular ordered electric potential difference regions in the 2D plane and key components of SSPEs. Consequently, the dissociation of LiTFSI is promoted, and the migration of Li-ions is accelerated. Moreover, a uniform LiF-rich solid electrolyte interphase efficiently inhibits the growth of lithium dendrites, guaranteeing excellent interfacial stability. The assembled Li//LiFePO₄ and Li//LiNi_0.6Co_0.2Mn_0.2O₂ full cells exhibit excellent reversible capacity and stable cycling performance at 30 °C. This study presents a strategy for improving the overall performance of SSPEs by fabricating nanofillers with highly ordered electric potential difference regions. Graphdiyne-based materials, which serve as nanofillers to optimize the performance of SSPEs through REPS, provide a wide scope for the practical application of ASSLMBs.