The development of electric vehicles and smart grids necessitates the search for next-generation secondary batteries possessing increased energy densities, with the lithium-sulfur (Li-S) battery being one of the most promising candidates satisfying these demands. Specifically, Li-S batteries are promising energy storage and conversion systems owing to their high theoretical specific energy capacity (1675 mAh g~(-1)) and energy density (2567 kWh kg~(-1)). However, the practical use of Li-S batteries is hindered by their low specific capacity, low coulombic efficiency, poor rate capability, and poor cycling stability caused by the low conductivity of sulfur (5×10~(-30) S cm~(-1)), dissolution of polysulfides (Li_2S_x, 2≤ x ≤ 8) in the electrolyte and their redox shuttling/parasitic reactions and high volume expansion during discharge. To overcome these drawbacks, many studies have focused on developing the design and materials of nanostructured host, electrolyte, interlayers, separators, additives, etc. Interconnected three-dimensional frameworks comprising multi-walled carbon nanotubes, graphene, or carbon particles offer a combination of constituent advantages and can thus be used to achieve superior energy conversion and storage properties.
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