Comb-like fluorine-modified polysiloxane-based solid electrolyte, preparation method and lithium battery

Abstract

This invention relates to the field of solid-state electrolyte technology, specifically to a comb-like fluorine-modified polysiloxane solid-state electrolyte, its preparation method, and a lithium-ion battery. The electrolyte is formed by crosslinking polyetheramine with comb-like fluorine-modified polysiloxane. The polysiloxane backbone provides flexibility, and side branches introduce -CF3 groups into trifluoromethylstyrene, promoting lithium-ion battery performance through an inductive effect. + The electrolyte enhances mechanical properties by crosslinking side-chain ethylene oxide with polyetheramine, improving interfacial stability and transport. The preparation method involves substitution, hydrosilylation, and crosslinking reactions, resulting in a simple process. The electrolyte exhibits an ionic conductivity of 2.19 × 10⁻⁶ at 60°C. ‑3 S·cm ‑1 It has a wide electrochemical stability window, and the assembled lithium battery has excellent cycle stability. At a 0.5C rate, the capacity retention rate is 80% after 100 cycles. It can solve the problems of low conductivity, morphological stability and main chain flexibility of traditional polysiloxane electrolytes.

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