Catalytic Effects of Nanocage Heterostructures in Lithium-Sulfur Batteries

With the increasing demand for high-energy-density energy storage systems in electric vehicles, smart grids, and portable electronic devices, the energy density of traditional lithium-ion batteries is approaching its theoretical limit. Lithium-sulfur (Li-S) batteries are regarded as strong candidates for next-generation high-performance energy storage systems due to their high theoretical energy density (2567 Wh kg−1), low cost, and environmental friendliness. However, the commercialization of Li-S batteries still faces key challenges such as the shuttle effect, sluggish reaction kinetics, volume expansion, and lithium anode corrosion. To address these issues, researchers have developed various functional materials and structural design strategies, among which heterostructures and nanocage host materials show significant advantages. This review systematically summarizes the basic principles, key problems, and solving strategies of lithium-sulfur (Li-S) batteries, focusing on the role of nanocage heterostructures in enhancing polysulfide adsorption, catalytic conversion, and structural stability, and outlines their future development path in high-energy-density Li-S batteries.