Toward Enhancing Low Temperature Performances of Lithium-Ion Transport for Metal-Organic Framework-Based Solid-State Electrolyte: Nanostructure Engineering or Crystal Morphology Controlling

Metal-organic frameworks (MOFs) have emerged as attractive candidates for Li⁺ conducting electrolytes due to their regular channels and controllable morphology, making their presence prominent in the field of solid-state lithium batteries. However, most MOF-based electrolytes are researched at or near room temperature, which poses a challenge to their practical applications at low temperatures. Herein, a thin layer flower-shaped 2D Cu-MOF (CuBDC-10)-based solid-state electrolytes (SSEs) for lithium-ion batteries (LIBs) are developed for facilitating Li⁺ transport at lower temperatures, which achieve an ion conductivity of 10^-4 S cm^-1 at -30 °C. The CuBDC-10-based SSE exhibits outstanding ionic conductivity over a wide temperature range of -40 to 100 °C (0.073-3.68 × 10^-3 S cm^-1). This work provides strategies for exploring MOF-based SSEs with high ionic transport performances at low temperatures.