Structural Regulation and Performance Enhancement of PVDF–HFP-Based Quasi-Solid-State Electrolytes via Nano-Barium Titanate Doping and Photocuring

Safety concerns regarding traditional lithium-ion batteries have garnered widespread attention, and solid-state batteries, with their superior safety and energy density, have emerged as the primary direction for the development of next-generation rechargeable batteries. Among various solid-state electrolytes, PVDF–HFP-based polymer solid-state electrolytes have garnered significant attention owing to their good flexibility, excellent processability, and mechanical strength. However, their low room-temperature ionic conductivity limits their practical application. To address this, this study adopts a composite quasi-solid-state electrolyte approach by introducing nano-BaTiO 3 into the PVDF–HFP-based quasi-solid-state electrolyte system and employs UV light curing technology for rapid fabrication. This approach not only enhances the electrolyte’s ionic conductivity but also strengthens its mechanical strength. Experimental results indicate that the introduced nano-barium titanate may restrict the movement of polymer chains, producing a synergistic effect with the cross-linked network formed by UV curing. This enables the electrolyte to achieve an ionic conductivity of 7.01 × 10 −4  S cm −1 at room temperature. At a current density of 0.2 mA cm −2 , the system can operate stably for 2200 h. At a 0.2 C rate, the battery exhibited a capacity retention of 93.55% after 120 cycles. This study provides a feasible approach for the preparation of safe and highly stable quasi-solid-state electrolytes.