Approaching high performancePVDF‐HFPbased solid composite electrolytes withLLTOnanorods for solid‐state lithium‐ion batteries

Abstract

Solid polymer electrolytes have the merits of high safety and energy density and lightweight. Therefore, they gradually become the key for commercial applications of solid batteries. In this study, a new type of solid composite electrolyte (SCE) is prepared by adding Li0.33La0.557TiO3 (LLTO) nanorods into poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) matrix. This SCE displays excellent thermal stability and mechanical properties. Moreover, it has been proven to sufficiently suppress the growth of lithium dendrites. When the content of the LLTO nanorods reaches 10 wt%, the SCE delivers a high ionic conductivity of 1.21 × 10−4 S cm−1 at 25°C and the electrochemical stability window of 4.7 V (vs Li+/Li). The NCM622/SCE/Li solid-state lithium-ion battery delivers a discharge specific capacity of 129.1 mAh g−1 at 0.5 C after 100 cycles, and the coulombic efficiency reaches 99%. These results demonstrate that the SCE is expected to become one of the most hopeful candidates for the coming generation of solid-state lithium-ion batteries.