Cellulose-based composite material comprising an electrically conductive material dispersed in a matrix comprising at least one plant-derived protein and a polymer of aleuritic acid, said composite material being obtainable by a process comprising the steps of dissolving at least one plant-derived protein and aleuritic acid in a dissolving solution to achieve a first mixture, dispersing an electrically conductive material in said first mixture to achieve a conductive ink, distributing said conductive ink on at least one side of a cellulose substrate to achieve a coated cellulose substrate, hot-pressing said coated cellulose substrate to obtain i) impregnation of the cellulose substrate with said conductive ink and ii) polymerization of aleuritic acid.