Preparation and properties of gel membrane containing porous PVDF-HFP matrix and cross-linked PEG for lithium ion conduction

• Published in: Frontiers of chemical engineering in China Vol. 2; no. 1; pp. 89 - 94
• Main Authors: Zhang, Mei, Zhang, Aiqing, Cui, Zhenyu, Zhu, Baoku, Han, Gaige, Xu, Youyi
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Higher Education Press 01.03.2008
• Subjects: Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Nanotechnology; Research Article; gel electrolyte; porous membrane; polyethylene glycol; lithium ion; poly(vinylidene fluoride-co-hexafluoropropylene)
• ISSN: 1673-7369; 1673-7474
• DOI: 10.1007/s11705-008-0011-6

Lithium ion conducting membranes are the key materials for lithium batteries. The lithium ion conducting gel polymer electrolyte membrane (Li-GPEM) based on porous poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) matrix and cross-linked PEG network is prepared by a typical phase inversion process. By immersing the porous PVDF-HFPmembrane in liquid electrolyte containing poly(ethylene glycol) diacrylate (PEGDA) and an initiator to absorb the liquid electrolyte at 25°C, and then thermally cross-linking at 60°C, the Li-GPEMis fabricated successfully. The measurements on its weight loss, mechanical and electrochemical properties reveal that the obtained Li-GPEM has better overall performance than the liquid and blend gel systems used as conductive media in lithium batteries. The ionic conductivity of the fabricated Li-GPEM can reach as high as 2.25 × 10 −3 S/cm at 25°C.