We report a new family of self-assembling nanostructured polymers for potential application as electrolytes in rechargeable lithium batteries. The ester groups of these amphiphilic methacrylate polymers are oligoethylene oxide segments terminated by a linear alkyl chain. The ethylene oxide segments are amorphous providing good lithium salt solubility and ionic conductivity, while the terminal alkyl segments crystallize and provide dimensional stability. The polymers self-assemble into nanometer-thick lamellar structures with alternating layers of conductive ethylene oxide and insulating alkyl layers. (C) 2004 Published by Elsevier B.V.