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Carbonate electrolytes have excellent chemical stability and high salt solubility, which are ideally practical choice for achieving high‐energy‐density sodium (Na) metal battery at room temperature. However, their application at ultra‐low temperature (−40 °C) is adversely affected by the instability of solid electrolyte interphase (SEI) formed by electrolyte decomposition and the difficulty of desolvation. Here, we designed a novel low‐temperature carbonate electrolyte by molecular engineering on solvation structure. The calculations and experimental results demonstrate that ethylene sulfate (ES) reduces the sodium ion desolvation energy and promotes the forming of more inorganic substances on the Na surface, which promote ion migration and inhibit dendrite growth. At −40 °C, the Na||Na symmetric battery exhibits a stable cycle of 1500 hours, and the Na||Na3V2(PO4)3 (NVP) battery achieves 88.2 % capacity retention after 200 cycles. [ABSTRACT FROM AUTHOR]

Potassium metal batteries (PMBs) are a compelling technology for large‐scale energy storage due to the abundance of potassium resources and high energy density. A vital obstacle to construct high‐performance PMBs is developing superior cathode materials. Tannin, a plant polyphenol, holding many active sites for redox reactions, is an auspicious high‐capacity cathode. However, the relatively poor conductivity and slight solubility in electrolyte deteriorate its capacity and cycle stability. Herein, the tannin is activated through a crosslinking reaction with polyaniline to obtain a composite cathode (i.e., ATN). It exhibits a high initial capacity of 172 mAh g−1 at 50 mA g−1, based on the electrochemical reaction mechanisms of embedding/releasing of K+ on CO and PF6− on NH. Moreover, to improve the cycling performance, a graphene oxide modified separator is developed to effectively retard the ATN shuttle. As a result, the capacity retention is significantly enhanced, for example, 82% over 300 cycles at 50 mA g−1. From a practical aspect, a full PMB of K@KxPy||ATN is built up, displaying high energy/power density and superior cycling stability, which is a step forward in the development of PMBs. [ABSTRACT FROM AUTHOR]

Constructing artificial solid‐electrolyte interphase (SEI) on the surface of Li metal is an effective approach to improve ionic conductivity of surface SEI and buffer Li dendrite growth of Li metal anode. However, constructing of homogenous ideal artificial SEI is still a great challenge. Here, a mixed lithium‐ion conductive Li2S/Li2Se (denoted as LSSe) protection layer, fabricated by a facile and inexpensive gas–solid reaction, is employed to construct stable surface SEI with high ionic conductivity. The Li2S/Li2Se‐protected Li metal (denoted as LSSe@Li) exhibits a stable dendrite‐free cycling behavior over 900 h with a high lithium stripping/plating capacity of 3 mAh cm−2 at 1.5 mA cm−2 in the symmetrical cell. Compared to bare Li anode, full batteries paired with LiFePO4, sulfur/carbon, and LiNi0.6Co0.2Mn0.2O2 cathodes all present better battery cycling and rate performance when LSSe@Li anode is used. Moreover, Li2Se exhibits a lower lithium‐ion migration energy barrier in comparison with Li2S which is proved by density functional theory calculation. [ABSTRACT FROM AUTHOR]

Lithium metal is an exciting anode candidate with extra high theoretical specific capacity for new high‐energy rechargeable batteries. However, uncontrolled Li deposition and an unsteady solid electrolyte interface seriously obstruct the commercial application of Li anodes in Li metal batteries. Herein, 3D carbon cloth (CC) supporting N‐doped carbon (CN) nanosheet arrays embedded with tiny Co nanoparticles (CC@CN‐Co) are employed as a lithiophilic framework to regulate homogenous Li nucleation/growth behavior in a working Li metal anode. The emergence of Li dendrites is supposed to be inhibited by the conductive 3D scaffold that reduces local current density. The uniform nucleation of Li can be guided by N‐containing functional groups as they have a strong interaction with Li atoms, and the tiny Co nanoparticles can provide active sites to guide Li deposition. As a result, the current CC@CN‐Co host exhibits Li dendrite–free features and stable cycling performance with a low overpotential (20 mV) throughout 800 h cycles. When paired with the typical LiFePO4 (LFP) cathode, the assembled CC@CN‐Co@Li//LFP@C full cell exhibits outstanding rate capability and improved cycling performance. [ABSTRACT FROM AUTHOR]

The research of sodium/potassium‐ion batteries (SIBs/KIBs) still has some way to go but its success could possibly radically alter the way electricity is stored and used. As the key part of battery technology, advances in electrode materials are instrumental in accelerating the uptake of these renewable and innovative storage solutions. This is where metal chalcogenides (MCs) that tick all the right boxes can fit in to fill the gap. In this review, an overview is provided on the recent progress of MCs, with an emphasis on nanostructured metal sulfides and selenides, and the impact that metal chalcogenides may have on the future of SIBs and KIBs technology is discussed by taking a glimpse at the diverse set of properties inherent in them. In addition, several promising strategies are highlighted to address the imminent challenges faced by MCs in SIBs and KIBs, hoping to cast an insightful outlook for possible future direction in this field. [ABSTRACT FROM AUTHOR]