Synthesis, dynamic properties and electrochemical stability of organic-inorganic hybrid polymer electrolytes with double core branched structures based on polyether, cyanuric chloride and alkoxysilane

摘要

A new organic-inorganic solid hybrid electrolyte based on 2,4,6-trichloro-1,3,5-triazine, triblock co-polymer poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminopropyl ether), poly(ethylene glycol) diglycidyl ether, and 3-(glycidyloxypropyl)trimethoxysilane doped with LiClO_4 salt is synthesized by a sol-gel process. Fourier transform infrared spectroscopy and ~(13)C NMR results reveal the successful synthesis of the organic-inorganic hybrid electrolyte. The conductivity of the hybrid electrolyte follows a VTF (Vogel-Tamman-Fulcher)-like behavior, implying that the diffusion of charge carriers is assisted by the segmental motions of polymer chains. The Li-ion mobility is determined from ~7Li static NMR linewidth and diffusion coefficient measurements; both are correlated with their ionic conductivities. The maximum ionic conductivity of 9.5 × 10~(-5) S cm~(-1) at 30℃ is obtained for the hybrid electrolyte with the [O]/[Li] ratio of 32. The electrochemical stability window of 4V ensures the hybrid electrolyte as a potential candidate for low voltage lithium ion batteries.