In Situ Constructing Robust and Highly Conductive Solid Electrolyte with Tailored Interfacial Chemistry for Durable Li Metal Batteries.

Employing nanofiber framework for in situ polymerized solid-state lithium metal batteries (SSLMBs) is impeded by the insufficient Li + transport properties and severe dendritic Li growth. Both critical issues originate from the shortage of Li + conduction highways and nonuniform Li + flux, as randomly-scattered nanofiber backbone is highly prone to slippage during battery assembly. Herein, a robust fabric of Li 0.33 La 0.56 Ce 0.06 Ti 0.94 O 3-δ /polyacrylonitrile framework (p-LLCTO/PAN) with inbuilt Li + transport channels and high interfacial Li + flux is reported to manipulate the critical current density of SSLMBs. Upon the merits of defective LLCTO fillers, TFSI - confinement and linear alignment of Li + conduction pathways are realized inside 1D p-LLCTO/PAN tunnels, enabling remarkable ionic conductivity of 1.21 mS cm -1 (26 °C) and t Li+ of 0.93 for in situ polymerized polyvinylene carbonate (PVC) electrolyte. Specifically, molecular reinforcement protocol on PAN framework further rearranges the Li + highway distribution on Li metal and alters Li dendrite nucleation pattern, boosting a homogeneous Li deposition behavior with favorable SEI interface chemistry. Accordingly, excellent capacity retention of 76.7% over 1000 cycles at 2 C for Li||LiFePO 4 battery and 76.2% over 500 cycles at 1 C for Li||LiNi 0.5 Co 0.2 Mn 0.3 O 2 battery are delivered by p-LLCTO/PAN/PVC electrolyte, presenting feasible route in overcoming the bottleneck of dendrite penetration in in situ polymerized SSLMBs.