Silica-assisted cross-linked polymer electrolyte membrane with high electrochemical stability for lithium-ion batteries

This study aims to prepare an organic-inorganic reticular polymer electrolyte. Isocyanate acts as a bridge that connects fumed silica and PEO molecular chains. The PEO-TDI-SiO2 solid polymer electrolytes developed can significantly have improved ionic conductivity of 0.12 mS cm(-1) at ambient temperature. This is because the TDI-SiO2 nanoparticles inhibits polymer crystallization which provides more continuous Li-ion transport pathways. Tests at 60 degrees C indicate that the cross-linked structure of covalent TSI bonded to PEO effectively enlarges the electrochemical window of the polymer electrolyte to 5.6 V. Also, the PTSI electrolyte membrane has a higher Li+ transference number of 0.33 compared to the PEO-LiTFSI electrolytes. It is worth noting that the assembled LiFePO4 vertical bar PTSI8%vertical bar Li cells deliver outstanding rate performance and stable cycling performance. All these considerable merits of PTSI membrane demonstrate that PTSI is a promising candidate that can be used as solid polymer electrolytes for the nextgeneration Li-ion batteries. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

This study successfully prepared a PEO-TDI-SiO2 solid polymer electrolyte with improved ionic conductivity and enlarged electrochemical window by introducing isocyanate as a bridge. The PTSI electrolyte membrane showed a higher Li+ transference number, delivering outstanding performance and stable cycling performance in LiFePO4 vertical bar PTSI8%vertical bar Li cells.