Toward a Synergistic Optimization of Porous Electrode Formulation and Polysulfide Regulation in Lithium-Sulfur Batteries

Abstract

The use of functional materials is a popular strategy to mitigate the polysulfide-induced accelerated aging of lithium-sulfur (Li-S) batteries. However, deep insights into the role of electrode design and formulation are less elaborated in the available literature. Such information is not easy to unearth from the existing reports on account of the scattered nature of the data and the big dissimilarities among the reported materials, preparation protocols, and cycling conditions. In this study, model functional materials known for their affinity toward polysulfide species, are integrated into the porous sulfur electrodes at different quantities and with various spatial distributions. The electrodes are assembled in 240 lithium-sulfur cells and thoroughly analyzed for their short- and long-term electrochemical performance. Advanced data processing and visualization techniques enable the unraveling of the impact of porous electrodes' formulation and design on self-discharge, sulfur utilization, and capacity loss. The results highlight and quantify the sensitivity of the cell performance to the synergistic interactions of catalyst loading and its spatial positioning with respect to the sulfur particles and carbon-binder domain. The findings of this work pave the road for a holistic optimization of the advanced sulfur electrodes for durable Li-S batteries. This research seeks to offer key insights into optimizing advanced electrodes for lithium-sulfur batteries. The study emphasizes the critical role of optimal catalyst quantity and strategic placement near sulfur particles or the carbon-binder domain. These factors notably impact capacity retention and rate-capability, governing the local balance between the conversion and migration rates of polysulfides.image