Waste-Derived Zn-Based ASEI Layer for Enhanced Lithium Anodes in Lithium–Sulfur Batteries

The formation of lithium (Li) dendrites on the anode during charge and discharge poses a significant challenge to the scalability of lithium-metal batteries (LMBs). This study presents an innovative strategy leveraging waste-derived Zn to create a hybrid in/ex situ artificial solid electrolyte interphase (ASEI) layer. The hybrid ASEI layer significantly improves the electrochemical performance of Li anodes compared to uncoated Li. In symmetrical cells, it demonstrates exceptional stability, maintaining a low overpotential of 9 mV over 400 cycles with a charge transfer resistance of 10.4 Ω, attributed to the high Li-ion diffusivity provided by the ASEI layer. Unlike the bare Li, which develops a rough, thick, and uneven surface with cracks and dendrites after extended cycling, the ASEI-coated anode exhibits a smooth and uniform surface. Furthermore, chemical analysis during cycling confirms the dynamic formation of beneficial LiZn within the ASEI layer. The performance of waste-derived ASEI layer is examined in the real condition by pairing it with sulfur cathode. The cell delivers a remarkable specific discharge capacity of 1085 mAh g⁻¹ at 0.1C and retains 68% of its initial capacity after 300 cycles at 0.2C, outperforming bare Li, which retains only 54% under the same conditions.