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Lithium–sulfur batteries have ultra–high energy density and are considered to be one of the most promising energy storage systems among all battery systems. However, due to various thorny problems, their commercial production has not yet been realized. The current experimental research normally lacks a systematic investigation into the conversion mechanism of the sulfur cathode from the electronic structure level. Actually, there is still a lack of powerful theoretical guidance for the design of high–performance Li–S batteries and the selection of modified materials still seems blind. In this article, with the chelated Fe‐polyvinyl pyrrolidone as the precursor, a series of Fe–based materials (e.g., Fe3O4@C, FeS@C, Fe3N@C) are synthesized as modified layers for battery separators, and the performance differences between them are systematically studied. It is found that the d–p band center model developed based on the d band center can reasonably combine the reaction potential of Li2S4 and performance differences. Simultaneously, the interaction between Li2S6 and the adsorption interface is simulated by ab initio molecular dynamics. This current work sheds light on promising material design for superior Li–S batteries both from a theoretical and experimental perspective. [ABSTRACT FROM AUTHOR]

As concerns about the safety of lithium‐ions batteries (LIBs) increases, aqueous zinc‐ion batteries (ZIBs) with a lower cost, higher safety, and higher co‐efficiency have attracted more and more interest. However, finding suitable cathode materials is still an urgent problem in ZIBs. In recent years, a lot of significant works have been reported, including manganese‐based cathodes, vanadium‐based cathodes, Prussian blue analog‐based materials, and sustainable quinone cathodes. In this review, some typical cathode materials are introduced. The detailed storage mechanisms and methods for improving the reaction kinetics of the zinc ions are summarized. Finally, the issues, challenges, and the research directions are provided. [ABSTRACT FROM AUTHOR]

Recently, Li‐ion batteries (LIBs) have attracted extensive attention owing to their wide applications in portable and flexible electronic devices. Such a huge market for LIBs has caused an ever‐increasing demand for excellent mechanical flexibility, outstanding cycling life, and electrodes with superior rate capability. Herein, an anode of self‐supported Fe3O4@C nanotubes grown on carbon fabric cloth (CFC) is designed rationally and fabricated through an in situ etching and deposition route combined with an annealing process. These carbon‐coated nanotube structured Fe3O4 arrays with large surface area and enough void space can not only moderate the volume variation during repeated Li+ insertion/extraction, but also facilitate Li+/electrons transportation and electrolyte penetration. This novel structure endows the Fe3O4@C nanotube arrays stable cycle performance (a large reversible capacity of 900 mA h g−1 up to 100 cycles at 0.5 A g−1) and outstanding rate capability (reversible capacities of 1030, 985, 908, and 755 mA h g−1 at 0.15, 0.3, 0.75, and 1.5 A g−1, respectively). Fe3O4@C nanotube arrays still achieve a capacity of 665 mA h g−1 after 50 cycles at 0.1 A g−1 in Fe3O4@C//LiCoO2 full cells. [ABSTRACT FROM AUTHOR]

Sn chalcogenides, including SnS, Sn2S3, and SnS2, have been extensively studied as anode materials for lithium batteries. In order to obtain one kind of high capacity, long cycle life lithium batteries anode materials, three-dimensional (3D) flower-like hierarchitectures constructed by SnS/SnS2 heterostructure nanosheets with thickness of ~20 nm have been synthesized via a simple one-pot solvothermal method. The obtained samples exhibit excellent electrochemical performance as anode for Li-ion batteries (LIBs), which deliver a first discharge capacity of 1277 mAhg−1 and remain a reversible capacity up to 500 mAhg−1 after 50 cycles at a current of 100 mAg−1. [ABSTRACT FROM AUTHOR]

Because they are safer and less costly than state-of-the-art Li-ion batteries, aqueous zinc-ion batteries (AZIBs) have been attracting more attention in stationary energy storage and industrial energy storage. However, the electrochemical reaction of H + in all of the cathode materials of AZIBs has been puzzling until now. Herein, highly oriented VO 2 monocrystals grown on a Ti current collector (VO 2 -Ti) were rationally designed as the research model, and such a well-aligned VO 2 cathode also displayed excellent zinc-ion storage capability (e.g., a reversible capacity of 148.4 mAh/g at a current density of 2 A/g). To visualize the H + reaction process, we used time-of-flight secondary-ion mass spectrometry. With the benefit of such a binder-free and conductor-free electrode design, a clear and intuitive reaction of H + in a VO 2 cathode is obtained, which is quite significant for unraveling the accurate reaction mechanism of VO 2 in AZIBs.

Recently, Li-ion batteries (LIBs) have attracted extensive attention owing to their wide applications in portable and flexible electronic devices. Such a huge market for LIBs has caused an ever-increasing demand for excellent mechanical flexibility, outstanding cycling life, and electrodes with superior rate capability. Herein, an anode of self-supported Fe 3 O 4 @C nanotubes grown on carbon fabric cloth (CFC) is designed rationally and fabricated through an in situ etching and deposition route combined with an annealing process. These carbon-coated nanotube structured Fe 3 O 4 arrays with large surface area and enough void space can not only moderate the volume variation during repeated Li + insertion/extraction, but also facilitate Li + /electrons transportation and electrolyte penetration. This novel structure endows the Fe 3 O 4 @C nanotube arrays stable cycle performance (a large reversible capacity of 900 mA h g -1 up to 100 cycles at 0.5 A g -1 ) and outstanding rate capability (reversible capacities of 1030, 985, 908, and 755 mA h g -1 at 0.15, 0.3, 0.75, and 1.5 A g -1 , respectively). Fe 3 O 4 @C nanotube arrays still achieve a capacity of 665 mA h g -1 after 50 cycles at 0.1 A g -1 in Fe 3 O 4 @C//LiCoO 2 full cells., (© 2020 Wiley-VCH GmbH.)