Blending based polyacrylonitrile/poly(vinyl alcohol) membrane for rechargeable lithium ion batteries

A gel polymer electrolyte based on polyacrylonitrile (PAN)/poly(vinyl alcohol) (PVA) blending membrane have been fabricated through non-solvent induced phase separation (NIPS) method followed by activation in liquid electrolyte of 1.0M LiPF6 in carbonate solvent. The blending compatibility of PVA/PAN is investigated through thermodynamics analyses and demonstrates the miscibility of PAN/PVA blending system. The blending membranes with weight ratio of PVA/PAN = 10: 90 and 20: 80 have great effect on morphology of both top and bottom surface. This characteristic exhibits the high electrolyte uptake (up to 585%), acceptable thermal stability, excellent ionic conductivity and electrochemical stability (up to 5.28 V). The application of PAN/PVA blending membrane has been demonstrated by a coin cell using Li metal as counter electrode at 1C, resulting in better long-term cycle stability in comparison to cells with Celgard2320 separator and the highest capacity retention of 96%.