The thesis project is focused on the synthesis of a new polymer-based electrolyte for Li-ion battery, which presents higher performances due to a novel nanocomposite additive called 'Phosphorene'. If the commercial electrolytes are usually in the liquid form thanks to their great properties, the research is currently trying to achieve important goals in the field of non-liquid electrolytes, due to the safety issues they can solve. Throughout the whole manuscript, all the procedures from the synthesis processes to the experimental ones are accurately presented and commented in order to be reproduced and understood. The nanoscale additive is embedded into the polymer matrix revealing that can boost cyclability, capacity retention and enhance ion transport properties.