Unveiling the Pivotal Parameters for Advancing High Energy Density in Lithium‐Sulfur Batteries: A Comprehensive Review

Abstract The lithium‐sulfur (Li‐S) battery stands as a strong contender for the next‐generation energy storage system, characterized by abundant sulfur resources, environmental sustainability, and high specific capacity. However, its energy density remains constrained by factors such as low sulfur loading and fraction in the cathode, excessive electrolyte, and an excess of anode. These mild conditions significantly limit the energy density of Li‐S batteries, making them less competitive. To achieve higher energy density, harsh operation conditions are necessary, but these remain challenging to implement, even in a lab‐scale production. In this comprehensive review, the emphasis will be on recent advancements in Li‐S batteries, specifically in the realm of designing high sulfur loading, high sulfur fraction, lean electrolyte, and low limited negative electrode Li‐S batteries. A visualizable model that illustrates the relationship between cell energy density and various cell parameters, underscoring the importance of exploring Li‐S batteries under extreme operating conditions for further development is provided. Furthermore, it will discussed the possibilities of achieving even higher energy density in Li‐S batteries and the challenges that need to be addressed to make them practical for real‐world applications.