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Aqueous batteries that use metal anodes exhibit maximum anodic capacity, whereas the energy density is still unsatisfactory partially due to the high redox potential of the metal anode. Current metal anodes are plagued by the dilemma that the redox potential of Zn is not low enough, whereas Al, Mg, and others with excessively low redox potential cannot work properly in aqueous electrolytes. Mn metal with a suitably low redox potential is a promising candidate, which was rarely explored before. Here, we report a rechargeable aqueous Mn‐metal battery enabled by a well‐designed electrolyte and robust inorganic–organic interfaces. The inorganic Sn‐based interface with a bottom‐up microstructure was constructed to preliminarily suppress water decomposition. With this bubble‐free interface, the organic interface can be formed via an esterification reaction of sucrose triggered by acyl chloride in the electrolyte, generating a dense physical shield that isolates water while permitting Mn2+ diffusion. Hence, a Mn symmetric cell achieves a superior plating/stripping stability for 200 hours, and a Mn||V2O5 battery maintains approximately 100 % capacity after 200 cycles. Moreover, the Mn||V2O5 battery realizes a much higher output voltage than that of the Zn||V2O5 battery, evidencing the possibility of increasing the energy density through using a Mn anode. This work develops a systematic strategy to stabilize a Mn‐metal anode for Mn‐metal batteries, opening a new door towards enhanced voltage of aqueous batteries. [ABSTRACT FROM AUTHOR]

A single‐electron transfer mode coupled with the shuttle behavior of organic iodine batteries results in insufficient capacity, a low redox potential, and poor cycle durability. Sluggish kinetics are well known in conventional lithium–iodine (Li−I) batteries, inferior to other conversion congeners. Herein, we demonstrate new two‐electron redox chemistry of I−/I+ with inter‐halogen cooperation based on a developed haloid cathode. The new iodide‐ion conversion battery exhibits a state‐of‐art capacity of 408 mAh gI−1 with fast redox kinetics and superior cycle stability. Equipped with a newly emerged 3.42 V discharge voltage plateau, a recorded high energy density of 1324 Wh kgI−1 is achieved. Such robust redox chemistry is temperature‐insensitive and operates efficiently at −30 °C. With systematic theoretical calculations and experimental characterizations, the formation of Cl−I+ species and their functions are clarified. [ABSTRACT FROM AUTHOR]

Li-S batteries are ones of the most promising secondary batteries owing to their high-energy density. However, Li-S batteries have some drawbacks, including the poor electrical conductivity and rapid capacity fading. In this work, MnO 2 nanosheets/carbon nanotubes composites are synthesized via a simple and rapid hydrothermal deposit route. The carbon nanotubes (CNTs) serve as conductive network for electron. MnO 2 nanosheets provide numerous sites to form strong chemical binding with polysulfide. The composite maintains a reversible capacity of 841 mA h g −1 after 100 cycles at 0.5 C, and the rate capacity of 1214 mA h g −1 , 1072 mA h g −1 , 877 mA h g −1 , and 689 mA h g −1 was measured at 0.2 C, 0.5 C, 1 C, 2 C, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] Although a large number of intercalation cathode materials for aqueous Zn batteries have been reported, limited intercalation capacity precludes achieving a higher energy density. Here we develop a high-performance aqueous Zn battery based on BiSb alloy (Bi 0.5 Sb 0.5) using a high-concentrated strong-basic polyelectrolyte. We demonstrate that a conversion-dissolution/deposition electrochemical mechanism (BiSb ↔ Bi + SbO 2 − ↔ Bi + SbO 3 − ↔ Bi 2 O 3) through in situ X-ray diffraction (XRD), Raman, and ex-situ X-ray photoelectron spectrometry (XPS) characterizations with the help of density functional theory calculations. The BiSb cathode delivers large capacity of 512 mAh g−1 at 0.3 Ag−1 and superior rate capability of 90 mAh g−1 even at 20 Ag−1, and long-term cyclability with capacity retentions of 184 mAh g−1 after 600 cycles at 0.5 Ag−1 and 130 mAh g−1 after 1300 cycles at 1 Ag−1. Remarkably, even at temperatures as low as −10 and −20 °C, capacities of 210 and 197 mAh g−1 are reserved at 1 Ag−1, respectively. Moreover, the prepared pouch Zn//BiSb battery delivers a high energy density of 303 Wh kg−1 BiSb at 0.3 Ag−1. When coupled with a high concentration polyelectrolyte, the Zn/BiSb battery exhibits an excellent performance over a wide temperature range (−40 to 40 °C). Our research reveals the metal cathode is promising for Zn batteries to achieve a high performance with the unique mechanism and alloys can be an effective approach to stabilize metal electrodes for cycling. [ABSTRACT FROM AUTHOR]