Effect of glass―ceramic filler on properties of polyethylene oxide―LiCF_3SO_3 complex

摘要

Lithium-ion conducting composite polymer electrolytes (CPE),(PEO)_8―LiCF_3SO_3 (PEO = polyethylene oxide) dispersed with a glass-ceramic, Li_(1.4)[Al_(0.4)Ge_(1.6)(PO_4)_3] as a filler have been prepared as films and their thermal, mechanical, electrical and electrochemical properties have been studied. The glass transition temperature increases with filler addition reaches a maximum value of ―39 ℃ for x = 7.5 wt.%, and then decreases. Enhancement in the electrochemical stability of the films is noted; a maximum working voltage of 3.75 V is found at x = 10 wt.%. Addition of filler decreases the ionic conductivity for x = 7.5 wt.%, σ = 1.6 x 10~(-7) S cm~(-1) which is a factor three lower than that for the PS complex. The E_a and log_(10)(σ_0) values of the composite polymer electrolytes consistently decrease with increasing x. The mechanical properties are enhanced with filler addition, a maximum tensile strength of 22.8 MPa, is obtained at x = 7.5―10 wt.%, a value which is three times higher than that for the PS complex.