Search

Manganese-based layered oxides are promising cathode materials for potassium-ion batteries (PIBs) due to their low cost and high theoretical energy density. However, the Jahn-Teller effect of Mn3+ and sluggish diffusion kinetics lead to rapid electrode deterioration and a poor rate performance, greatly limiting their practical application. Here, we report a Co/Al co-substitution strategy to construct a P3-type K0.45Mn0.7Co0.2Al0.1O2 cathode material, where Co3+ and Al3+ ions occupy Mn3+ sites. This effectively suppresses the Jahn-Teller distortion and alleviates the severe phase transition during K+ intercalation/de-intercalation processes. In addition, the Co element contributes to K+ diffusion, while Al stabilizes the layer structure through strong Al-O bonds. As a result, the K0.45Mn0.7Co0.2Al0.1O2 cathode exhibits high capacities of 111 mAh g−1 and 81 mAh g−1 at 0.05 A g−1 and 1 A g−1, respectively. It also demonstrates a capacity retention of 71.6% after 500 cycles at 1 A g−1. Compared to the pristine K0.45MnO2, the K0.45Mn0.7Co0.2Al0.1O2 significantly alleviates severe phase transition, providing a more stable and effective pathway for K+ transport, as investigated by in situ X-ray diffraction. The synergistic effect of Co/Al co-substitution significantly enhances the structural stability and electrochemical performance, contributing to the development of new Mn-based cathode materials for PIBs. [ABSTRACT FROM AUTHOR]

The practical application of hard carbon in sodium‐ion batteries is limited by insufficient reversible capacity and low initial Coulombic efficiency (ICE), which are caused by the lack of active sites and unstable electrode/electrolyte interface. Herein, a biomass‐derived hard carbon material based on tea stems is proposed, which exhibits an ultrahigh ICE of 90.8%. This remarkable ICE is attributed to the presence of an inorganic‐rich, thin, and robust solid electrolyte interface (SEI) layer. Furthermore, the material demonstrates excellent cycling stability, showing a capacity retention of 99.5% after 500 cycles at 280 mA g−1. Additionally, when it works as the anode material in a sodium‐ion full cell without presodiation, it reaches a high energy density of 212 Wh kg−1 and a superior stability, e.g., retaining 93.1 mAh g−1 after 1000 cycles at 1 A g−1 with a capacity retention of 91.3%. The sodium storage capacity of this material is primarily attributed to a combined adsorption‐intercalation/filling effect as confirmed by in situ XRD and ex situ Raman analyses. These findings make this biomass‐derived hard carbon material a promising candidate for commercial application of sodium‐ion batteries, achieving high performance at low cost. [ABSTRACT FROM AUTHOR]

Rechargeable zinc‐air batteries (RZABs) are one of the most promising next‐generation energy‐storage technologies for stationary applications (home and industry), wearable and portable electronics, and transportation (including electric vehicles) due to their high energy density, environmental friendliness, safety, and low cost. However, RZABs still face serious challenges (such as sluggish oxygen reactions, poor durability, inferior reversibility of the zinc anode, and low cell energy efficiency) that conspire against their widespread commercialization. The reactions that occur at the three key components of the RZAB (air cathode, zinc anode, and electrolyte) co‐operatively conspire against its performance. Thus, this review focuses on the bifunctional electrocatalytic events at the cathode (i. e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER)). That is in addition to the recent developments aimed at mitigating the performance‐limiting events at the anode and the electrolytes. This review directs the attention of researchers and users to the critical areas for the development of the next‐generation RZABs. [ABSTRACT FROM AUTHOR]

Even though lithium ion batteries (LIBs) have seen extensive applications during the past 20 years, the anode materials which have realized commercialization are mainly restricted to graphite and Li4Ti5O12. However, because of the limited capacity of these two intercalation‐type anodes, they cannot meet the higher requirements in energy density of some applications. Very few types of high‐capacity anode materials have been successfully commercialized, mainly due to the inevitable large volume change during lithium insertion/extraction. Herein, a promising anode material, CaV4O9, which shows both high gravimetric capacity of more than 600 mAh g–1 with a safe average discharge potential of about 0.8 V, and near‐zero volume change character like Li4Ti5O12, is identified. The specific lithium storage mechanism and the origin of near‐zero volume change character are revealed. Considering the superior performance endowed by these unique intrinsic properties, CaV4O9 shows great potential for commercialized anode material and may promote innovation in LIBs. [ABSTRACT FROM AUTHOR]

On‐chip microsupercapacitors (MSC) with facile fabrication procedures, high integration design, and superior performance are desired as an energy storage device for microelectronics. Hence, a novel procedure is proposed to fabricate an asymmetric microsupercapacitor (AMSC), employing interwoven nanowire (NW) network electrodes of poly(3,4‐ethylenedioxythiophene) coated titanium oxynitride (P‐TiON) and vanadium nitride (VN) NW as a cathode and an anode, respectively. The interwoven NWs with a high mass loading offer a sufficient electrochemical reaction area and rapid electron/ion transport pathway, delivering superior energy and power densities. With the LiCl/polyvinyl alcohol electrolyte, the assembled P‐TiON//VN AMSC can achieve a wide voltage window from 0 to 1.8 V with an excellent areal capacitance of 72 mF cm−2, a high areal energy density of 32.4 μWh cm−2 (at 0.9 mW cm−2), an outstanding power density of 45 mW cm−2 (at 21.9 μWh cm−2), and a good cycling performance. Furthermore, the substrate‐free electrodes exhibit outstanding integrability, and the system on one printed circuit board including two AMSCs in series and a LED demonstrates excellent practicability. [ABSTRACT FROM AUTHOR]

The emerging electrochemical energy storage systems beyond Li‐ion batteries, including Na/K/Mg/Ca/Zn/Al‐ion batteries, attract extensive interest as the development of Li‐ion batteries is seriously hindered by the scarce lithium resources. During the past years, large amounts of studies have focused on the investigation of various electrode materials toward emerging metal‐ion batteries to realize high energy density, high power density, and a long cycle life. In particular, vanadium‐based nanomaterials have received great attention. Vanadium‐based compounds have a big family with different structures, chemical compositions, and electrochemical properties, which provide huge possibilities for the development of emerging electrochemical energy storage. In this review, a comprehensive overview of the recent progresses of promising vanadium‐based nanomaterials for emerging metal‐ion batteries is presented. The vanadium‐based materials are classified into four groups: vanadium oxides, vanadates, vanadium phosphates, and oxygen‐free vanadium‐based compounds. The structures, electrochemical properties, and modification strategies are discussed. The structure–performance relationships and charge storage mechanisms are focused on. Finally, the perspectives about future directions of vanadium‐based nanomaterials for emerging energy storage devices are proposed. This review will provide comprehensive knowledge of vanadium‐based nanomaterials and shed light on their potential applications in emerging energy storage. [ABSTRACT FROM AUTHOR]

Abstract: Rechargeable aqueous Zn‐based batteries, benefiting from their good reliability, low cost, high energy/power densities, and ecofriendliness, show great potential in energy storage systems. However, the poor cycling performance due to the formation of Zn dendrites greatly hinders their practical applications. In this work, a trilayer 3D CC‐ZnO@C‐Zn anode is obtained by in situ growing ZIFs (zeolitic‐imidazolate frameworks) derived ZnO@C core–shell nanorods on carbon cloth followed by Zn deposition, which exhibits excellent antidendrite performance. Using CC‐ZnO@C‐Zn as the anode and a branch‐like Co(CO3)0.5(OH)x·0.11H2O@CoMoO4 (CC‐CCH@CMO) as the cathode, a Zn–Co battery is rationally designed, displaying excellent energy/power densities (235 Wh kg−1, 12.6 kW kg−1) and remarkable cycling performance (71.1% after 5000 cycles). Impressively, when using a gel electrolyte, a highly customizable, fiber‐shaped flexible all‐solid‐state Zn–Co battery is assembled for the first time, which presents a high energy density of 4.6 mWh cm−3, peak power density of 0.42 W cm−3, and long durability (82% capacity retention after 1600 cycles) as well as excellent flexibility. The unique 3D electrode design in this study provides a novel approach to achieve high‐performance Zn‐based batteries, showing promising applications in flexible and portable energy‐storage systems. [ABSTRACT FROM AUTHOR]

Fast‐charging lithium‐ion batteries are pivotal in overcoming the limitations of energy storage devices, particularly their energy density. There is a burgeoning interest in boosting energy storage performance through enhanced fast‐charging capabilities. However, the challenge lies in developing batteries that combine high rates, long cycle life, high capacity, and safety. This review emphasizes the importance of fundamentals and design principles of fast charging, identifying the transport of ion/electron within the electrodes/electrolytes' bulk phase and at phase boundaries as the crucial rate‐limiting steps for fast charging. Such as ion transport tunnel regulation, interfacial modification, defect engineering and multiphase systems, various optimization strategies improve the stable and exceptional electrochemical reaction kinetics for electrodes. Constructing stable solid electrolyte interfaces and adjusting solvation structures further enhance the Li+ diffusion kinetics of electrolytes. The review critically assesses the impacts and limitations of these strategies, suggesting future research directions and insights for advancing fast‐charging lithium‐ion batteries. It is anticipated that this review will inspire and guide the systematic evolution of fast‐charging technologies. [ABSTRACT FROM AUTHOR]

On‐chip microbatteries have attracted growing attention due to their great feasibility for integration with miniaturized electronic devices. Nevertheless, it is difficult to get both high energy/power densities in microbatteries. An increase in the thickness of microelectrodes may help to boost the areal energy density of device, yet it often leads to terrible sacrifice in its power density due to the longer electron and ion diffusion distances. In this work, a quasi‐solid‐state on‐chip Ni–Zn microbattery is designed based on a hierarchical ordered porous (HOP) Ni@Ni(OH)2 microelectrode, which is developed by an in situ anodizing strategy. The fabricated microelectrode can optimize ion and electron transport simultaneously due to its interconnected ordered macropore–mesopore network and high electron conductivity. As the thickness of microelectrode increases, the areal energy density of HOP Ni@Ni(OH)2 microelectrode shows an ascending trend with negligible sacrifice in power density and rate performance. Impressively, this Ni–Zn microbattery achieves excellent energy/power densities (0.26 mW h cm−2, 33.8 mW cm−2), outperforming most previous reported microenergy storage devices. This study may provide new direction in high‐performance and highly safe microenergy storage units for next‐generation highly integrated microelectronics. [ABSTRACT FROM AUTHOR]

Searching for new‐type cathodes to enhance the capacity of Na‐ion batteries is one of the hot spots in energy storage systems. Many sodium insertion transition metal oxides, i.e., Na‐Mn‐O compounds, are intensively studied owing to their high voltage, abundant resources, and low toxicity. However, its relatively low capacity greatly limits its application. Here, a new synergistic composite, 0.44Na4Mn2O5•0.56Na0.7MnO2, is developed by a feasible method of organic‐acid‐assisted drying and heat treatment. This synergistic composite cathode delivers a reversible sodium storage capacity as high as 278.0 mAh g−1 and stable framework structure due to the synergistic effect. It is achieved by the synergistic effect of high capacity Na4Mn2O5 with multiple Na+ ions insert/extract sites and stable Na0.7MnO2 with layered structure. Even when tested at a high mass loading of 7.42 mg cm−2, this composite cathode demonstrates stable cycling over 400 cycles for sodium storage. Moreover, when coupled with hard carbon anode, Na‐ion full battery delivers excellent charge/discharge performance with capacity retention of 84.0%, showing great application potential in the large‐scale energy storage field. Synergistic composite structured xNa4Mn2O5•(1−x)Na0.7MnO2 is synthesized for the first time. The synergistic composite cathode delivers high reversible sodium storage capacity and stable framework structure due to the synergistic effect. The new synergistic composite structured 0.44Na4Mn2O5•0.56Na0.7MnO2 is a promising cathode material for high‐energy density Na‐ion batteries. [ABSTRACT FROM AUTHOR]