Rechargeable aqueous zinc (Zn) batteries are promising for large-energy storage because of their low cost, high safety, and environmental compatibility, but their implementation is hindered by the severe irreversibility of Zn metal anodes as exemplified by water-induced side reactions (H 2 evolution and Zn corrosion) and dendrite growth. Here, we find that the introduction of a hydrophobic carbonate cosolvent into a dilute aqueous electrolyte exhibits a much stronger ability to address the reversible issues facing Zn anodes than that with hydrophilic ones. Among the typical carbonates (ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate (DEC)), DEC as the most hydrophobic additive enables the strongest breaking of water's H-bond network and replaces the solvating H 2 O in a Zn 2+ -solvation sheath, which significantly reduces the water activity and its decomposition. Additionally, DEC molecules preferentially adsorb onto the Zn surface to create an H 2 O-poor electrical double layer and render a dendrite-free Zn 2+ -plating behavior. The formulated hybrid 2 m Zn(OTf) 2 + 7 m DEC electrolyte endows the Zn electrode with an ability to achieve high cycling stability (over 3500 h at 5 mA cm −2 with 2.5 mA h cm −2 ) and supports the stable operation of Zn||V 2 O 5 • nH 2 O full battery. This efficient strategy with hydrophobic cosolvent suggests a promising direction for designing aqueous battery chemistries.

This review article aims to provide insight into the research status of the potassium‐sulfur (K‐S) system, feature the challenges facing this technology, and present possible research directions for the realization of its practical applications. We begin with an introduction to the fundamental electrochemistry of K‐S batteries and emphasize the distinctions between K‐S technology and the well‐established lithium‐sulfur (Li‐S) system. Then, we focus on the development of the materials involved in K‐S batteries in terms of cathodes, K anodes, and various electrolyte systems. Finally, we provide several possible research directions to make the K‐S system a reality, with the emphasis, from our point of view, on the attempts to construct practical parameters for K‐S batteries by adopting the critical metrics of the current Li‐S system.

Flexible devices play an important role in various fields such as electronics, industry, healthcare, military, space exploration, and so on. Traditional materials used for flexible devices include silicon, inorganic oxides,...

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Layer-structured black phosphorus (BP) demonstrating high specific capacity has been viewed as a very promising anode material for future high-energy-density Li-ion batteries (LIBs). However, its practical application is hindered by large volume change of BP and poor mechanical stability of BP anodes by traditional slurry casting technology. Here, a free-standing flexible anode composed of BP nanosheets and nanocellulose (NC) nanowires is fabricated via a facile vacuum-assisted filtration approach. The constructed free-standing BP@NC composite anode offers three-dimensional (3D) mixed-conducting network for Li+/e– transports. The substrate of NC film has a certain flexibility up to 10.2% elongation that can restrain the volume change of BP and electrode during operation. In addition, molecular dynamic (MD) simulation and density function theory (DFT) show the greatly enhanced Li+ diffusion in BP@NC composite where the Li ions receive less repulsive force at the interface of BP interlayer and nanocellulose. Benefiting from above multifunction of nanocellulose, the BP@NC composite exhibits high capacities of 1020.1 mAh g–1 at 0.1 A g–1 after 230 cycles and 994.4 mAh g–1 at 0.2 A g–1 after 400 cycles, corresponding to high capacity retentions of 87.1% and 84.9%, respectively. Our results provide a low-cost and effective strategy to develop advanced electrodes for next-generation rechargeable batteries.

All-solid-state sodium batteries (ASSBs) have attracted ever-increasing attention due to their enhanced safety, high energy density, and the abundance of raw materials. One of the remaining key issues for the practical ASSB is the lack of good superionic and electrochemical stable solid-state electrolytes (SEs). Design and manufacturing specific functional materials used as high-performance SEs require an in-depth understanding of the transport mechanisms and electrochemical properties of fast sodium-ion conductors on an atomic level. On account of the continuous progress and development of computing and programming techniques, the advanced computational tools provide a powerful and convenient approach to exploit particular functional materials to achieve that aim. Herein, this review primarily focuses on the advanced computational methods and ion migration mechanisms of SEs. Second, we overview the recent progress on state-of-the-art solid sodium-ion conductors, including Na-β-alumina, sulfide-type, NASICON-type, and antiperovskite-type sodium-ion SEs. Finally, we outline the current challenges and future opportunities. Particularly, this review highlights the contributions of the computational studies and their complementarity with experiments in accelerating the study progress of high-performance sodium-ion SEs for ASSBs.

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Current mature commercial anode materials of lithium-ion batteries (LIBs), such as graphite and Li4Ti5O12, have been unable to meet the rapidly growing demand for high storage capacity and ultrafast charging. In recent years, many two-dimensional (2D) materials, including graphene, transition metal dichalcogenides, transition metal oxides, transition metal carbides and nitrides, and monoelemental materials, have been used as anode materials because of their large specific surface areas, numerous active sites, and outstanding transport rate of lithium ions. On the basis of the research status in recent years, in this review, we introduce the structures and characteristics of these 2D nanomaterials. Then, the advantages and disadvantages of these 2D materials in LIBs are compared. The defects of 2D materials can be improved by compositing them with other materials, and the electrochemical properties of 2D materials can be improved. Furthermore, the prospects and development of 2D materials in flexible LIBs are evaluated and strategies to overcome the difficulties are proposed.