Gel polymer electrolytes composed of acrylonitrile-methylmethacrylate (AM) copolymer and 1 M LiClO4-ethylene carbonate (EC)/propylene carbonate (PC) are prepared. The ionic conductivity reaches 1.9 x 10(-3) S cm(-1) in a gel polymer electrolyte with 20 wt.% of AM copolymer and 80 wt.% of LiClO4-EC/PC at room temperature. These systems showed no solvent exudation from the matrix polymer due to enhanced compatibility between AM copolymer and organic liquid electrolyte. A Li/gel polymer electrolyte/LiMn2O4 cell has a reversible capacity of 132 mAh g(-1) in the voltage range of 3.0-4.3 Vat the C/5 rate and shows good cycling performance with a coulombic efficiency >99%. (C) 2001 Elsevier Science B.V. All rights reserved.