Energy Storage System Based on Recycled Polypropylene and Its Use in Lithium–Sulfur and Lithium-Ion Batteries

Nontoxic, eco-friendly, and high-energy-density sulfurated poly(propylene) (S/PP-waste) has been prepared in a one-step vulcanization process from recycled poly(propylene) waste and used as a cathode material in lithium–sulfur (Li–S) batteries. A sulfur loading of up to 50.4 wt % was achieved. In S/PP-waste, the sulfur is covalently bound to the polymer matrix, selectively resulting in a solid phase transition during charge and discharge. Consequently, the polysulfide shuttle can be avoided, which results in satisfactory electrochemical performance with ultralong cycle life and a low capacity decay per cycle of ∼0.018% at 0.5C. S/PP-waste was also explored for the first time as an anode material in LiMn 2 O 4 -based Li-ion full cells. Its good electrochemical performance as well as its recycled nature make it a promising energy storage material for the future.