A novel gel polymer electrolyte, based on alkylene oxide macromonomer, was specially designed and synthesized for gel electrolyte purpose. A tri-functional macromonomer having a molecular weight of 8000 revealed to be the best candidate for preparing the gel electrolyte from the mechanical property aspect. The liquid retention ability of the cross-linked network polymer prepared from the above macromonomer was explored. It was confirmed that the polymer network based on the macromonomer retained a large amount of liquid electrolyte over 80 wt.% in stable state. (C) 2000 Elsevier Science Ltd. All rights reserved.