Zeolitic imidazolate framework enables practical room-temperature operation of solid-state lithium batteries

The decent flexibility and processability of solid-state polymer electrolytes (SPEs) endow them with broad development prospects in the solid-state lithium-based batteries field. Nevertheless, the poor room-temperature ionic conductivity of SPEs severely hinders their practical applications. Herein, we design a functionalized poly (vinylidene fluoride) (PVDF)-based electrolyte, and an ionic conductivity elevation is achieved by directly introducing zeolitic imidazolate framework-90 (ZIF-90) as filler into SPE. The metal ion sites of ZIF-90 can adsorb TFSI⁻ with a large adsorption energy of −1.35 eV to facilitate the dissociation of LiTFSI. The SPE modified with ZIF-90 delivers the prominent ionic conductivity of 0.62 mS cm⁻¹ at 30 °C and the low activation energy of 0.20 eV. Simultaneously, cells fabricated with LiFePO₄ cathode exhibit the high specific discharge capacity of 118 mAh g⁻¹ after 300 cycles at 1 C (0.44 mA cm⁻²) at room temperature. This work provides an efficient and promising strategy of fabricating competitive SPEs for solid-state lithium-based batteries.