Polypropylene-supported and nano-Al2O3 doped poly(ethylene oxide)-poly(vinylidene fluoride-hexafluoropropylene)-based gel electrolyte for lithium ion batteries

A new gel polymer electrolyte (GPE) is reported in this paper In this GPE blending polymer of poly(ethylene oxide) (PEO) with poly(vinylidene fluoride-hexafluoropropylene) (P(VdF-HFP)) doped with nano-Al2O3 and supported by polypropylene (PP) is used as polymer matrix namely PEO-P(VdF-HFP)-Al2O3/PP The performances of the PEO-P(VdF-HFP)-Al2O3/PP membrane and the corresponding GPE are characterized with mechanical test CA EIS TGA and charge-discharge test It is found that the performances of the membrane and the GPE depend to a great extent on the content of doped nano-Al2O3 With doping 10 wt % nano-Al2O3 in PEO-P(VdF-HFP) the mechanical strength from 9 3 MPa to 14 3 MPa the porosity of the membrane increases from 42% to 49% the electrolyte uptake from 176% to 273% the thermal decomposition temperature from 225 C to 355 C and the ionic conductivity of corresponding GPE is improved from 27 x 10(-3) S cm(-1) to 38 x 10(-3) S crn(-1) The lithium ion battery using this GPE exhibits good rate and cycle performances (C) 2010 Elsevier BV All rights reserved