In order to improve the film-forming properties of polyether-based polymer electrolytes a new family of materials was synthesized. The structures described in this work involve a cellulosic ether backbone on which oligoethers were grafted and crosslinked in various proportions via urethane chemistry and to which lithium perchlorate was subsequently added as a source of ionic species. The resulting networks were fully characterized in terms of glass transition temperature, dynamic mechanical properties and ionic conductivity. With respect to the optimized polyether-based networks studied previously, the introduction of polysaccharide chains does not alter the basic features neither qualitatively nor quantitatively.