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Lithium–sulfur batteries are recognized as one of the most promising next‐generation energy‐storage technologies owing to their high energy density and low cost. Nevertheless, the shuttle effect of polysulfide intermediates and the formation of lithium dendrites are the principal reasons that restrict the practical adoption of current Li–S batteries. Adjustable frameworks, structural variety, and functional adaptability of covalent organic frameworks (COFs) have the potential to overcome the issues associated with Li–S battery technology. Herein, a summary is presented of emerging COF materials in addressing the challenging problems in terms of sulfur hosts, modified separators, artificial solid electrolyte interphase layers, and solid‐state electrolytes. This comprehensive overview focuses on the design and chemistry of COFs used to upgrade Li–S batteries. Furthermore, existing difficulties, prospective remedies, and prospective research directions for COFs for Li–S batteries are discussed, laying the groundwork for future advancements in this class of fascinating materials.

Solid polymer electrolytes (SPEs)-based all-solid-state lithium-sulfur batteries (ASSLSBs) have attracted extensive research attention due to their high energy density and safe operation, which provide potential solutions to the increasing need for harnessing higher energy densities. There is little progress made, however, in the development of ASSLSBs to improve simultaneously energy density and long-term cycling life, mostly due to the "shuttle effect" of lithium polysulfide intermediates in the SPEs and the low interfacial compatibility between the metal lithium anode and the SPE. In this work, the issues of solid/solid interfacial architecturing through atomic layer deposition of Al 2 O 3 on poly(ethylene oxide)-lithium bis(trifluoromethanesulfonyl)imide SPE surface are effectively addressed. The Al 2 O 3 coating promotes the suppression of lithium dendrite formation for over 500 h. ASSLSBs fabricated with two layers of Al 2 O 3 -coated SPE deliver high gravimetric/areal capacity and Coulombic efficiency, as well as excellent cycling stability and extremely low self-discharge rate. This work provides not only a simple and effective approach to boost the electrochemical performances of SPE-based ASSLSBs, but also enriches the fundamental understanding regarding the underlying mechanism responsible for their performance.

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Heterostructured materials are interesting because they may combine two or more material building blocks that together generate new types of heterointerfaces with unusual properties. Using them to construct large‐scale 3D frameworks further extends their utility in electrochemical applications because it exposes more interfaces and active sites. In this study, electrostatic interactions are used to wrap polyhedra particles of zeolitic imidazolate frameworks with graphene oxide (GO) nanosheets to prepare the composite structure. Pyrolyzing this structure generates a 3D porous carbon framework (PCF) composed of polyhedral‐shaped hollow carbon coated with reduced GO. The size of the polyhedral macropores can be adjusted from nanometer scale to micrometer scale. The PCFs generate a continuous network of heterostructured carbon with a large surface area and large pore volumes that are particularly useful as porous electrodes in lithium–sulfur batteries. The PCF/S composite electrode exhibits a high discharge capacity of 1151 mAh g−1 at 1 C and a low capacity decay of 0.035% per cycle after 650 cycles.