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Solid polymer electrolytes (SPEs) are among the most promising candidates for solid‐state batteries due to their easy processibility, interface compatibility, and cost efficiency. However, the trade‐off between the ionic conductivity and mechanical strength of SPEs, which has persisted for decades, hinders their application in solid‐state lithium (Li) metal batteries. In this study, the aim is to break this trade‐off by utilizing poly(p‐phenylene benzobisoxazole) (PBO) nanofibers as a mechanically strong backbone and polyethylene oxide (PEO) as an ionically conductive network. The PBO/PEO composite electrolyte reduces the crystallinity of PEO while increasing the mechanical strength (74.4 MPa, ≈14 times that of PEO). Thus, PBO/PEO simultaneously improves ionic conductivity and mechanical strength both at room temperature and elevated temperatures, enabling uniform and smooth Li deposition. Thus, a long cycle life of solid‐state Li symmetric cells for 1000 h at 60 °C is achieved, and stable cycling of solid‐state Li metal full batteries at 60 °C and even 100 °C. Furthermore, the solid‐state pouch cell using this SPE exhibits excellent performance reliably after bending. The study clearly indicates that simultaneously improving mechanical properties and conductivity is the indispensable path to the practical application of solid‐state electrolytes. [ABSTRACT FROM AUTHOR]

Copper (Cu) is the most attractive electrocatalyst for CO2 reduction to multi‐carbon (C2+) products with high economic value in considerable amounts. However, the rational design of a structurally stable Cu‐based catalyst that can achieve high activity and stability towards C2+ products remain a grand challenge. Here, a highly stable nickel oxygenate/Cu electrocatalyst is developed with abundant NiOOH/Cu interfaces by in situ electrochemical reconstruction. The nickel oxygenate/Cu electrocatalyst achieves a superior Faradaic efficiency of 86.3 ± 3.0% and a record partial current density of 2085 A g−1 for C2+ products with long‐term stability. In situ experimental and theoretical studies demonstrates that the exceptional performance in generating C2+ products is attributed to the presence of the NiOOH/Cu interfaces which increase *CO coverage, lower energy barrier for *CO coupling and stabilize *OCCO simultaneously. This work provides new insights into the rational design of electrocatalysts to achieve stable and efficient electrocatalytic CO2 reduction capabilities. [ABSTRACT FROM AUTHOR]

Achieving the solid–solid conversion of sulfur is a fundamental solution to eliminating the shuttling of soluble polysulfides and improving the cycling stability of lithium‐sulfur batteries. However, the sluggish solid reaction kinetics seriously challenge the battery performance. In this work, a micropore‐confined catalysis strategy to achieve the smooth solid–solid conversion of sulfur is proposed. It is realized by storing sulfur in a microporous carbon host with narrow pore size and uniformly distributed single‐atom Co catalytic sites. The microporous structure avoids the contact of electrolyte solvents with the inner sulfur, preventing the formation and dissolution of polysulfides and efficiently suppressing sulfur loss during cycling. The introduced single‐atom Co catalytic sites promote the charge transfer to accelerate the solid–solid conversion of sulfur. When coupled with a liquid carbonate electrolyte, the battery exhibits a remarkably high Coulombic efficiency (CE) of ≈99.88% and a minimal capacity decay rate of ≈0.016% per cycle for 1000 cycles at 0.5 C. Even when coupled with the solid‐state electrolyte, the battery still delivers a significantly high capacity of 1100 mAh g−1 and a remarkably high CE of ≈99.83% over 200 cycles. This work reveals a promising solution for developing practical stable Li─S batteries. [ABSTRACT FROM AUTHOR]

Zinc batteries hold great potential for stationary energy storage but suffer from severe dendrite growth, corrosion, and hydrogen evolution troubles in aqueous electrolytes. Despite the impressive efficacy of non‐flammable hydrous organic electrolytes in addressing these problems, the insufficient ionic conductivity hinders the rate capability and practicability of hydrous organic Zn batteries. Here, methanol is proposed as a co‐solvent for ethylene glycol (EG)‐based hydrous organic electrolytes, where its methyl terminal group can interrupt the continuous intermolecular hydrogen bond network among EG. The new hydrous organic electrolyte exhibits a doubled ionic conductivity without sacrificing the exceptional nonflammability. As a result, the Zn anode exhibits a long‐term cycling stability over 4000 h at 0.5 mA cm−2, a high Coulombic efficiency of 99.5%, high‐rate capability up to 20 mA cm‒2, and impressive low‐temperature tolerance of ‒60 °C. The Zn||V2O5 pouch cell with the electrolyte is capable of operating under extreme operation conditions involving needling, package breakage, and even exposure to fire. This work paves an avenue toward electrolyte design for high‐rate practical Zn batteries and beyond. [ABSTRACT FROM AUTHOR]

Graphite has paved the way for commercial lithium‐ion batteries and shows great potential as an anode for high‐energy potassium‐ion batteries (PIBs) due to its low‐potential charge/discharge plateau. However, the restricted diffusion of large K+ in graphite causes difficulties in generating the stage‐one graphite‐intercalation compound (GIC) KC8 at high rates and results in a low plateau capacity and an inferior rate performance. It is discovered that the formation of high‐stage GICs (prior to KC24) is the rate‐controlling step of K+ intercalation, which is key to forming KC8. Here, a carbon anode material containing the medium‐size discrete graphitic crystallites is reported, produced by heating non‐graphitizable carbon above 2800 °C. This carbon anode material promotes the formation of KC8 due to the accelerated K+ diffusion especially at the rate‐controlling step and the sufficient reactive sites, which leads to a record‐high plateau capacity of 293 mAh g−1 and an excellent rate performance with 180 mAh g−1 at 500 mA g−1. For comparison, the respective values for graphite are only 242 and 51 mAh g−1. This study provides new insights into K+‐intercalation chemistry and shall promote the design of carbon anode materials for high‐energy and high‐power PIBs and even other energy storage systems. [ABSTRACT FROM AUTHOR]

The introduction of sulfur redox electrocatalysts has been considered to be an effective strategy to anchor polysulfides on the cathode and reduce the energy barriers of the reactions. Due to the complexity of sulfur redox reactions (SRR/SER), there exist few descriptors to correlate the catalytic performance and the underlying electronic structures of a given catalyst, which inhibits the development of lithium−sulfur catalysts. In this article, upon mullite oxide SmMn2O5 with various substitutional defects, density functional theory calculations are used to probe the structure–property relationships. It is found that there exists no scaling relationship among the polysulfide binding energies, indicating that the catalytic performance can be tuned by a key intermediate individually. Statistical analysis of various models with different S‐containing intermediates shows that only the Li2S4 binding energy has a linear correlation with the overpotential, showing the dominant role of Li2S4 anchoring to determine the catalytic performance. The electronic structure analysis combined with machine learning further quantitatively verifies the coeffect of charge transfer, electronegativity, and work function on the binding strength of the polysulfide Li2S4. This work provides a theoretical understanding of the complex SRR/SER mechanisms and sheds light on the rational design of a sulfur redox catalyst. [ABSTRACT FROM AUTHOR]

Carbon materials show their importance in electrochemical energy storage (EES) devices as key components of electrodes, such as active materials, conductive additives and buffering frameworks. To meet the requirements of vastly developing markets related to EES, especially for electric vehicles and large scale energy storage, the rational design of functional carbon materials with the basis of a deep understanding of the structure‐property relationships is demanded, in which dimensionality variations and hybridizations of the carbon materials play critical roles in improving electrochemical performances of EES devices. This review focuses on the dimensionality manipulation in functional carbon materials, including transition, matching and integration, to optimize the reaction space, interface and framework in electrodes, respectively. This review gives a comprehensive review on how the dimensionality manipulation improves performance of the carbon‐based electrodes in kinetics optimization, electron transfer acceleration, mechanical stabilization and thermal dissipation upon charging/discharging. The report ends with a critical perspective on the future challenges facing carbon‐based electrodes with dimensionality dependence. The progress highlighted here is expected to provide a guidance for the precise design and targeted synthesis of dimensionality varied carbon‐based electrode materials towards safe and high performance EES devices and the resulting optimized energy deployments. [ABSTRACT FROM AUTHOR]

The lithium–sulfur (Li–S) battery is a next generation high energy density battery, but its practical application is hindered by the poor cycling stability derived from the severe shuttling of lithium polysulfides (LiPSs). Catalysis is a promising way to solve this problem, but the rational design of relevant catalysts is still hard to achieve. This paper reports the WS2–WO3 heterostructures prepared by in situ sulfurization of WO3, and by controlling the sulfurization degree, the structure is controlled, which balances the trapping ability (by WO3) and catalytic activity (by WS2) toward LiPSs. As a result, the WS2–WO3 heterostructures effectively accelerate LiPS conversion and improve sulfur utilization. The Li–S battery with 5 wt% WS2–WO3 heterostructures as additives in the cathode shows an excellent rate performance and good cycling stability, revealing a 0.06% capacity decay each cycle over 500 cycles at 0.5 C. By building an interlayer with such heterostructure‐added graphenes, the battery with a high sulfur loading of 5 mg cm−2 still shows a high capacity retention of 86.1% after 300 cycles at 0.5 C. This work provides a rational way to prepare the metal oxide–sulfide heterostructures with an optimized structure to enhance the performance of Li–S batteries. [ABSTRACT FROM AUTHOR]

Graphitic carbon is grown on SnSiOx+2 nanofibers to obtain nanocables, into the core of which carbon network and atomic‐level dispersion of SnOx were embedded. The resultant nanocables with a highly conductive carbon framework exhibit outstanding cycling performance with high specific capacity and excellent cycling stability even at high current rates. [ABSTRACT FROM AUTHOR]

The low Coulombic efficiency and serious security issues of lithium (Li) metal anode caused by uncontrollable Li dendrite growth have permanently prevented its practical application. A novel SiO2 hollow nanosphere-based composite solid electrolyte (SiSE) for Li metal batteries is reported. This hierarchical electrolyte is fabricated via in situ polymerizing the tripropylene gycol diacrylate (TPGDA) monomer in the presence of liquid electrolyte, which is absorbed in a SiO2 hollow nanosphere layer. The polymerized TPGDA framework keeps the prepared SiSE in a quasi-solid state without safety risks caused by electrolyte leakage, meanwhile the SiO2 layer not only acts as a mechanics-strong separator but also provides the SiSE with high room-temperature ionic conductivity (1.74 x 10-3 S cm-1) due to the high pore volume (1.49 cm³ g-1) and large liquid electrolyte uptake of SiO2 hollow nanospheres. When the SiSE is in situ fabricated on the cathode and applied to LiFePO4/SiSE/Li batteries, the obtained cells show a significant improvement in cycling stability, mainly attributed to the stable electrode/electrolyte interface and remarkable suppression for Li dendrite growth by the SiSE. This work can extend the application of hollow nanooxide and enable a safe, efficient operation of Li anode in next generation energy storage systems. [ABSTRACT FROM AUTHOR]

Graphene oxide is effectively reduced by H2S and a graphene/sulfur hybrid is simultaneously obtained. The resulting graphene sheets interlink, forming a curly and porous structure that accompanies a uniform distribution of sulfur on the graphene sheets. The product is a promising electrode for Li‐S batteries and provides a novel strategy for the removal of H2S. [ABSTRACT FROM AUTHOR]

Selenium (Se) shows promise as a cathode candidate for all‐solid‐state lithium (Li) batteries due to its impressive theoretical volumetric energy density, much higher electronic conductivity, and improved safety in comparison to those for sulfur (S). An active cathode additive, lithium iodide (LiI) is demonstrated, to address the major challenge for all‐solid‐state Li–Se batteries, namely the sluggish redox kinetics resulting from the huge solid‐state conversion barrier. The LiI additive enhances Li+ transport and provides catalytic sites for Se cathode, thus endowing the batteries with accelerated reaction kinetics and extra capacity. DFT calculation and experimental analysis clearly reveal that LiI additive efficiently accelerates the conversion between polyselenide intermediates and Li2Se. With the above advantages, the battery with LiI using Li6PS5Br electrolyte gives an outstanding capacity of 862 mAh gSe−1 beyond the theoretical specific capacity of Se and a superlong life over 1800 cycles at 1C under room temperature. This work offers a simple strategy to facilitate the kinetics of all‐solid‐state Se cathodes and paves the way for the practicality of high‐capacity and long‐life all‐solid‐state Li–Se batteries. [ABSTRACT FROM AUTHOR]

The detrimental shuttle effect in lithium–sulfur batteries mainly results from the mobility of soluble polysulfide intermediates and their sluggish conversion kinetics. Herein, presented is a multifunctional catalyst with the merits of strong polysulfides adsorption ability, superior polysulfides conversion activity, high specific surface area, and electron conductivity by in situ crafting of the TiO2‐MXene (Ti3C2Tx) heterostructures. The uniformly distributed TiO2 on MXene sheets act as capturing centers to immobilize polysulfides, the hetero‐interface ensures rapid diffusion of anchored polysulfides from TiO2 to MXene, and the oxygen‐terminated MXene surface is endowed with high catalytic activity toward polysulfide conversion. The improved lithium–sulfur batteries deliver 800 mAh g−1 at 2 C and an ultralow capacity decay of 0.028% per cycle over 1000 cycles at 2 C. Even with a high sulfur loading of 5.1 mg cm−2, the capacity retention of 93% after 200 cycles is still maintained. This work sheds new insights into the design of high‐performance catalysts with manipulated chemical components and tailored surface chemistry to regulate polysulfides in Li–S batteries. [ABSTRACT FROM AUTHOR]

Carbon materials are the most promising anodes for sodium‐ion batteries (SIBs), but low initial Coulombic efficiency (ICE) and poor cyclic stability hinder their practical use. It is shown herein, that an effective but simple remedy for these problems can be achieved by deactivating defects in the carbon with Al2O3 nanocluster coverage. A 3D porous graphene monolith (PGM) is used as the model material and Al2O3 nanoclusters around 1 nm are grown on the defects of graphene. It is shown that these Al2O3 nanoclusters suppress the decomposition of conductive sodium salt in the electrolyte, resulting in the formation of a thin and homogenous solid electrolyte interphase (SEI). In addition, Al2O3 nanoclusters appear to reduce the detrimental etching of the SEI by hydrogen fluoride (HF) and improve its stability. Therefore, after the introduction of Al2O3 nanoclusters, the ICE, cyclic stability, and rate capability of the PGM are greatly improved. A higher ICE (70.2%) and capacity retention (82.9% after 500 cycles at 0.5 A g−1) than those of normally reported for large surface area carbons are achieved. This work indicates a new way to deactivate defects and modify the SEI of carbon materials, and hopefully accelerate the commercialization of carbon materials as anode materials for SIBs. The defects in graphene are deactivated by the coverage of Al2O3 nanoclusters, which suppress the irreversible decomposition of the sodium conductive salt in sodium‐ion battery electrolytes. An ion‐conducting, thin and homogenous solid electrolyte interphase is formed, resulting in high initial Coulombic efficiency, good rate capability, and cyclic stability for sodium‐ion storage. [ABSTRACT FROM AUTHOR]