Sodium‐ion batteries (SIBs) have become an auspicious candidate for large‐scale energy storage by cause of low cost, natural abundance, and similar working principle with lithium‐ion batteries (LIBs). At present, there is an urgent need to explore superior anode materials with rapid and stable sodiation/desodiation. Herein, 3D self‐assembled VS4 curly nanosheets hierarchitectures (VS4‐CN‐Hs) are developed for SIB anodes, where VS4 possesses a large theoretical sodium storage capacity, and the building block of nanosheets has large exposed surface area to the electrolyte as well as the constructed hierarchitectures can provide abundant buffer space to alleviate the volume expansion. As a result, VS4‐CN‐Hs anode possesses excellent electrochemical performance under a wide voltage window of 0.01–3.0 V, such as high reversible capacity of 863 mA h g−1 at 0.1 A g−1, marvelous rate feature (444 mA h g−1 at 10 A g−1), and extralong cycle stability (386 mA h g−1 after 1000 times at 5 A g−1).

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Na3V2(PO4)2O2F (NVPOF) is considered a promising cathode material for sodium-ion batteries (SIBs) on account of its attractive electrochemical properties such as high theoretical capacity, stable structure, and high working platform. Nevertheless, the inevitable interface problems like sluggish interfacial electrochemical reaction kinetics and poor interfacial ion storage capacity seriously hinder its application. Construction of chemical bonding is a highly effective way to solve interface problems. Herein, NVPOF with interfacial V–F–C bonding (CB-NVPOF) is developed. The CB-NVPOF cathode exhibits high rate capability (65 mA h g–1 at 40C) and long-term cycling stability (a capacity retention of 77% after 2000 cycles at 20C). Furthermore, it shows impressive electrochemical performance at temperatures as low as −40 °C, delivering a capacity of 56 mA h g–1 at 10C and a capacity retention of ∼80% after 500 cycles at 2C. The interfacial V–F–C bond engineering significantly advances the electronic conductivity, Na+ diffusion, as well as interface compatibility at −40 °C. This study provides a novel idea for improving the electrochemical performance of NVPOF-based cathodes for SIBs aiming for low-temperature applications.

Alkali metal‐ion batteries (SIBs and PIBs) and multivalent metal‐ion batteries (ZIBs, MIBs, and AIBs), among the next‐generation rechargeable batteries, are deemed appealing alternatives to lithium‐ion batteries (LIBs) because of their cost competitiveness. Improving the electrochemical properties of electrode materials can greatly accelerate the pace of development in battery systems to cover the increasing demands of realistic applications. Vanadium tetrasulfide (VS4) is known as a prospective electrode material due to its unique one‐dimensional atomic chain structure with a large chain spacing, weak interactions between adjacent chains, and high sulfur content. This review summarizes the synthetic strategies and recent advances of VS4 as cathodes/anodes for rechargeable batteries. Meanwhile, we describe the structural characteristics and electrochemical properties of VS4. And we describe in detail its specific applications in batteries such as SIBs, PIBs, ZIBs, MIBs, and AIBs as well as modification strategies. Finally, the opportunities and challenges of VS4 in the domain of energy research are described.

Potassium-ion batteries (PIBs) have received widespread interest on account of low redox potential, low price, and high abundance of potassium. However, attributing to the large radius of K+ ions, the structure of electrode material is easily damaged during the potassiation/depotassiation process. Herein, the unique chemical bonding of encapsulating V5.45S8 nanoparticles in N,S codoped multichannel carbon nanofibers (CB-VS@NSCNFs) is designed through electrospinning and in situ vulcanization techniques. The anchoring effect (V–C chemical bonding) of the V5.45S8 nanoparticles with carbon carriers assists in shortening the K+/e– transport path and alleviating the structural changes, which is highlighted to acquire a stable cycle lifespan. Also, codoped multichannel carbon nanofibers provide abundant active sites for pseudocapacitive behavior to achieve fast kinetics. As a synergistic result, when CB-VS@NSCNFs are evaluated as anode material for PIBs, they exhibit a high reversible capacity of 411 mA h g–1 at 0.1 A g–1, decent rate property with a capacity of up to 123 mA h g–1 at 6 A g–1, and good cycling stability of 500 cycles at 1 A g–1.