Abstract
Solid polymer electrolytes have been prepared by encapsulating plasticized polymer electrolytes based on poly(tetraethylene glycol diacrylate) into the pores of Celgard® microporous membranes. Electrolyte membranes with thicknesses of ∼40 μm have been prepared. The conductivity of the electrolyte is determined by the porosity of the membrane, and a conductivity of 
at room temperature has been demonstrated. These electrolytes showed good compatibility with Li and an electrochemical stability window spanning the range of 0.0 to ∼4.5 V vs. Li+/Li. The excellent chemical and electrochemical stabilities enabling the use of the membranes in rechargeable Li batteries have been confirmed by the discharge/charge cycling of Li/solid polymer 
cells at room temperature.