High-performance gel polymer electrolytes derived from PAN-POSS/PVDF composite membranes with ionic liquid for lithium ion batteries

The gel polymer electrolytes (GPEs) with poly(acrylonitrile-polyhedral oligomeric silsesquioxane)/poly(vinylidene fluoride) (PAN-POSS/PVDF) blends as free-standing porous membrane and ionic liquid (IL) as absorption substance were successfully prepared. By tuning the content of PAN-POSS, the porosity and absorptivity of the blended membranes could be regulated. Due to the higher porosity and absorptivity, the ionic conductivity of GPEs with 15 wt% PAN-POSS reaches to 1.91 x 10(-3) S cm(-1) at 20 C-o. Meanwhile, the electrolytes also show excellent mechanical properties, thermal stability, and fire resistance. More importantly, the high electrochemical window of 4.6 V (vs. Li/Li+) has been acquired and the testing cells with Li metal anode and LiFePO4 cathode show a tolerable rate performance. Such prepared GPEs are expected to be applied to lithium batteries with high safety and electrochemical performance.

Automated summary

The study successfully prepared gel polymer electrolytes with high porosity and absorbance, exhibiting high ionic conductivity, excellent mechanical properties, thermal stability, and fire resistance. By controlling the material composition, the performance of the mixed film can be adjusted, and the test cells show acceptable performance.