Poly(dimethylsiloxane) hybrid gel polymer electrolytes of a porous structure for lithium ion battery

Abstract

A porous fabric membrane (XSAE) was prepared from the crosslinked hybrid composite of poly(dimethylsiloxane)/polyacrylonitrile/poly(ethylene oxide) (PDMS/PAN/PEO) to simultaneously act as a separator and functionalized gel polymer electrolytes (GPEs). The porous structure enables hybrid membranes (XSAE) to absorb a large amount of electrolyte solution, thereby significantly increases the performance of GPEs. The addition of PDMS induces phase segregation to form a porous morphology and deteriorates the crystallization of PAN. Owing to these effects, the ionic conductivity of the gel hybrid membrane at room temperature more than doubled, and the lithium transport number increased from 0.41 up to 0.58. Compared with a composite membrane without PDMS (XAE), the battery application half-cell capacities of both XAE and XSAE were close to 150mAhg−1 at 0.1C. However, at high C rate (3C), the capacities of composite membranes with PDMS (PDMS/PAN/PEO) can reach 114mAhg−1, significantly higher than that without PDMS (70mAhg−1). Moreover, the aforementioned properties of the XSAE membrane allow this composite to act as both an ionic conductor and separator.