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

Abstract

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 LiMn2O4-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.

Covalent Organic Framework/Aluminum Oxide Composite Nanosheets as a Separator for High-Performance Lithium–Sulfur Batteries

“…With the widespread use of portable/wearable electronics and electric vehicles, the demand for energy storage devices with high energy density and high security is growing rapidly. , Thereinto, lithium–sulfur (Li–S) batteries have been widely investigated owing to their superhigh theoretical specific capacity of 1675 mAh g –1 and high theoretical energy density of 2600 Wh kg –1 . − However, the shuttle effect caused by the dissolution of polysulfide in an organic liquid-based electrolyte leads to a short cycle life of Li–S batteries. − In recent years, various strategies have been adopted to restrain the shuttle of polysulfide, including the development of an efficient composite sulfur cathode, modification or intercalation of the separator, optimization of electrolytes, and protection of the lithium anode. − The separator, as an indispensable part in Li–S batteries, not only effectively prevents physical contact and internal short-circuit between positive and negative electrodes but also acts as an ion sieve for lithium transport during electrochemical processes. Nevertheless, most commercial polyolefin separators have large pore diameters, some permeability to polysulfides, and poor ability to capture polysulfide.…”