No abstract

Abstract-Solid polymer electrolyte for lithium ion batteries consisting of polyethylene oxide (PEO) and lithium trifluoromethanesulfonate (LiCF 3 SO 3 ) was prepared by a ball milling method followed by a hot pressing process. Various contents of Li salts (5, 10, 15 and 20 wt %) were studied. The samples were investigated for crystallinity and glass transition temperature by DSC and ionic conductivity was measured by the impedance. XRD patterns confirmed the degree of crystallinity of solid polymer electrolyte. The mechanical property was measured by tensile testing machine. It was found that the PEO composite that composed of 15 wt% of LiCF 3 SO 3 exhibited the highest conductivity at room temperature as 1.00 × 10 -6 Scm -1 , whereas the glass transition temperature (T g ), the melting temperature (T m ) and the degree of crystallinity decreased with the increasing of Li salt content.Index Terms-Lithium salt, polyethylene oxide, solid polymer electrolyte.