Preparation and property of gel membranes containing porous PVDF-HFP and crosslinked PEG for lithium ion conduction

Lithium ion conducting membranes are the key materials for lithium batteries.The lithium ion conducting gel polymer electrolyte membranes(Li-GPEMs) containing PVDF-HFP porous matrix filled with crosslinked PEG network are presented and prepared via the following route:The porous membranes of PVDF-HFP are obtained by typical phase inversion process.By immersing porous PVDF-HFP membrane in liquid electrolyte containing PEGDA at 25℃ to absorb the liquid electrolyte,and then thermal crosslinking at 60℃,the Li-GPEMs are fabricated successfully.The measurements in weight loss,mechanics and electrochemistry reveal that the obtained Li-GPEMs have the better overall performances than the liquid or blend gel system while being used as conduction medium in lithium batteries.The highest conductivity of Li-GPEM can reach as high as 2.25×10-3S/cm.