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Sodium‐ion batteries (SIBs) with wide operating temperature are regarded as promising candidates for large‐scale energy storage systems. However, SIBs operating under elevated temperature aggravate the electrolyte decomposition with unstable cathode‐electrolyte interphase (CEI), causing a rapid capacity degradation. Herein, anion receptor tris(pentafluorophenyl)borane (TPFPB) is selected as electrolyte additive to construct robust NaF‐rich CEI. The strong interactions between anion and TPFPB via the electron‐deficient boron atoms weaken ClO4− solvation and promote the coordination capability between solvents and Na+ cations, demonstrating greatly improved oxidative stability. Na3V2(PO4)3 cathode in TPFPB‐containing electrolyte delivers long‐term stability with a capacity retention of 86.9% after 100 cycles at a high cut‐off voltage of 4.2 V (vs. Na+/Na) and a high temperature of 60 °C. Besides, TPFPB also works well with enhanced performance over a temperature range from −30 to 60 °C. This study proposes a prospective method by manipulating the solvation chemistry for constructing high‐temperature rechargeable SIBs. [ABSTRACT FROM AUTHOR]

Given the merits of affordable cost, superior low‐temperature performance, and advanced safe properties, sodium‐ion batteries (SIBs) have exhibited great development potential in large scale energy storage applications. Among various emerging carbonaceous anode materials applied for SIBs, hard carbon (HC) has recently gained significant attention regarding their relatively low cost, wide availability, and optimal overall performance. However, the insufficient initial Coulombic efficiency (ICE) of HC is the main bottlenecks, which is inevitably hindering their further commercial applications. Herein, an in‐depth holistic exposition about the reasons causing the unsatisfied ICE and the recent advances on effective improvement strategies are comprehensively summarized in this review, which have been divided into two aspects including the intrinsic property (degree of graphitization, pore structure, defect, et al.) and the extrinsic factor (electrolyte, electrode materials, et al.). In addition, future prospects and perspectives on HC to enable practical application in SIBs are also briefly outlined. [ABSTRACT FROM AUTHOR]

Sodium (Na) metal anodes are promising candidates for various batteries with high energy density and high‐power density, however, the dendrite growth of Na metal is impeding their practical applications. The binary alloy Na–K is in the liquid state at room temperature with a wide composition range, which renders it inherently free from solid dendrite growth. Whereas the application of Na–K alloy is plagued by the lack of a wettable matrix to immobilize the liquid metal. Herein, a facile method is reported to introduce oxygen‐rich functional groups into carbon fiber cloth (O‐CFC), which is initially Na–K phobic yet turns into superwetting after the treatment. The superwetting behavior of the O‐CFC can be attributed to the favorable enthalpy changes as a result of the introduction of O‐rich functional groups. The superwetting property of the O‐CFC exhibits good universality, which can be extended to melting Na and K metals. By adopting the superwetting O‐CFC as a host for liquid Na–K alloy, the liquid metal can be well retained in the matrix and deliver a stable cycling for >1600 h. The concept of enthalpy‐driven wettability regulation can be enlightening for the host material design of other liquid metals and alloys. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs), as promising cathode materials for sodium‐ion batteries (SIBs), have received extensive research interest due to their appealing characteristics, e.g., the low cost of their raw materials, easy manufacturing, open frameworks, and high theoretical specific capacity. There are some challenges for PBAs cathodes, however, hindering their performance output, making them currently unacceptable for practical applications. To improve the performance and cycling stability of PBAs, a clear in‐depth understanding of the relationship of their electrochemical reaction process to their ion insertion/extraction mechanisms and structural evolution is extremely important. Nowadays, advanced characterization techniques have become an important tool to guide the construction of high‐performance PBAs cathodes. In this review, the various advances by using advanced characterization techniques to reveal the reaction mechanisms for PBAs cathodes are summarized and discussed. By appreciating how the advanced characterization techniques to guide fabrication of high‐performance PBAs or reveal their detailed reaction mechanisms, it is hoped that this review can assist readers to find more valuable and advanced technologies to help to resolve some key problems and enhance their performance so as to accelerate the practical application of PBAs cathode for SIBs. [ABSTRACT FROM AUTHOR]

Organic electroactive compounds hold great potential to act as cathode material for organic sodium‐ion batteries (OSIBs) because of their environmental friendliness, sustainability, and high theoretical capacity. Although some organic electrodes have been developed with good performance, their practical application is still obstructed by some inherent drawbacks such as low conductivity and solubility in organic electrolytes. In addition, research on OSIBs has been mainly focused on the performance of electrodes on the material level and neglected the trade‐off relationship between the high redox potentials and specific capacities. Almost all organic cathodes used in OSIBs lack the ability to be charged first in half‐cells because of the absence of detachable sodium ions, resulting in low attractiveness when assembling full cells with hard carbon as anode. Here, this review presents several existing reaction mechanisms in OSIBs and designs of organic cathode materials. Furthermore, strategies are proposed in order to provide guidelines for improving their performance according to some critical parameters (output voltage, specific capacity, and cycle life) in potential practical OSIBs, and some accounts of organic materials assembled in full cells are summarized. Finally, the challenges and prospects of organic electrodes for OSIBs are also discussed in this review. [ABSTRACT FROM AUTHOR]

The practical application of lithium–sulfur batteries is hampered by the sluggish redox reaction kinetics and severe lithium polysulfide (LiPS) migration, especially under high sulfur loading and lean electrolyte scenarios. Strategies to catalyze the sulfur liquid/solid conversion within a "hermetic" nano‐container have been proposed, where the LiPS migration and sluggish reaction kinetics can be simultaneously addressed. Herein, to realize rapid LiPS conversion and slow LiPS migration, the sulfur species are packed by a hermetic catalytic interface, constructed by the phosphorene/graphene heterostructure. The 2D phosphorene/graphene stacking has two unique benefits: 1) a direct electron transfer avoiding any insulating media, resulting in an exceptional catalytic effect on LiPS conversion; ii) favorable charge rearrangement that enhances chemisorption toward LiPS and limits LiPS crossover. The proposed highly flexible hermetic interface with strong van der Waals serves as a bifunctional nano‐container to pack sulfur species and promote sulfur redox reactions, which gives rise to excellent battery performances: a high areal capacity of 5.57 mAh cm−2 under a low electrolyte/sulfur ratio of 5.7 mL g−1. This work affords a coupling strategy that embraces interfacial and structural engineering to promote kinetic reactions of sulfur conversions under electrolyte‐lean conditions. [ABSTRACT FROM AUTHOR]

Growing demands on energy storage devices have inspired a tremendous amount of research on rechargeable batteries. Future generations of rechargeable batteries are required to have high energy density, long lifespan, low cost, high safety, low environmental impact, and wide commercial affordability. To achieve these goals, significant efforts are underway to focus on electrolyte chemistry, electrode engineering, and new designs for energy storage systems. Herein, a comprehensive overview of an innovative sodium‐based hybrid metal‐ion battery (HMIBs) for advanced next‐generation energy storage is presented. Recent advances on sodium‐based HMIBs from the development of reformulated or novel materials associated with Na+ ions and other metal ions (such as Li+, K+, Mg2+, Zn2+, etc.), are summarized in this work. Daniell cell and "rocking‐chair" type batteries are covered. Finally, the current challenges and future remedies in terms of the design and fabrication of new electrolytes, cathodes, and anodes for advanced HMIBs are discussed in this report. [ABSTRACT FROM AUTHOR]

Single‐atom Pt and bimetallic Pt3Co are considered the most promising oxygen reduction reaction (ORR) catalysts, with a much lower price than pure Pt. The combination of single‐atom Pt and bimetallic Pt3Co in a highly active nanomaterial, however, is challenging and vulnerable to agglomeration under realistic reaction conditions, leading to a rapid fall in the ORR. Here, a sustainable quasi‐Pt‐allotrope catalyst, composed of hollow Pt3Co (H‐PtCo) alloy cores and N‐doped carbon anchoring single atom Pt shells (Pt1N‐C), is constructed. This unique nanoarchitecture enables the inner and exterior spaces to be easily accessible, exposing an extra‐high active surface area and active sites for the penetration of both aqueous and organic electrolytes. Moreover, the novel Pt1N‐C shells not only effectively protect the H‐PtCo cores from agglomeration but also increase the efficiency of the ORR in virtue of the isolated Pt atoms. Thus, the H‐PtCo@Pt1N‐C catalyst exhibits stable ORR without any fade over a prolonged 10 000 cycle test at 0.9 V in HClO4 solution. Furthermore, this material can offer efficient and stable ORR activities in various organic electrolytes, indicating its great potential for next‐generation lithium–air batteries as well. A novel Quasi‐Pt‐allotrope, that is, hollow metallic PtCo@Pt1N‐C, has outstanding oxygen reduction reaction performance both in aqueous and organic electrolytes. The synergistic structure of Pt3Co and single Pt atoms provides more active sites and reduces the binding energy of O2. The porous carbon offers tunnels for good flow of electrolytes and protects the alloy from agglomeration. [ABSTRACT FROM AUTHOR]