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The development of high‐performance cathode materials for next‐generation lithium‐ion batteries (LIBs) is urgently needed. Among the potential cathode candidates, ternary layer oxide LiNi1/3Co1/3Mn1/3O2 (LNCM) has attracted considerable attention due to its high voltage discharge, large theoretical specific capacity, stable chemical structure and low cost. However, Li+/Ni2+ cation mixing and low conductivity have resulted in poor long‐term cyclability, voltage drop and capacity degradation during high‐rate charging. To address these issues, a sol‐gel technique together with an annealing treatment was used to prepare LNCM with well‐defined structure and good morphology. The material obtained by heating the LNCM precursor at 850 °C for 12 h (LNCM‐850/12) exhibited an initial discharge specific capacity of 217.9 mAh g−1 at 0.2 C and maintained a high reversible capacity of 116.1 mAh g−1 after 200 cycles. The LNCM‐850/12 electrode also demonstrated superior rate capacity and exceptional cycling stability due to its well‐defined structure, low Li+/Ni2+ cation mixing and good morphology. These characteristics improve the electrical/ionic conductivity, reduce the charge transfer resistance and shorten the Li+ diffusion distance, ultimately accelerating the Li+ insertion and extraction. Overall, the careful control of calcination time in LNCM synthesis provides valuable insights for the development of advanced cathodes for LIBs. [ABSTRACT FROM AUTHOR]

The rapid depletion of lithium resources and the increasing demand for electrical energy storage have stimulated the pursuit of emerging electrochemical energy storage. Aqueous zinc ion batteries (ZIBs) are highly sought after for their low cost, high safety, and increased environmental compatibility. However, the search for suitable cathode materials is still tricky for a wide range of researchers. Vanadium oxides (VxOy), with their abundant vanadium valence, easily deformable V−O polyhedrons, and tunable chemical compositions, are of significant advantage in developing emerging materials. This work provides a detailed review of different VxOy for the application in aqueous ZIBs. The current problems and optimization strategies of VxOy cathode materials are systematically discussed. Finally, the current challenges and possible directions for future research of VxOy cathode materials in aqueous ZIBs are presented. [ABSTRACT FROM AUTHOR]

Ethylene glycol‐assisted sol‐gel method is employed for preparing LiNi1/3Co1/3Mn1/3O2 used as cathode material in lithium‐ion batteries. The prepared material has higher c/a value and lower cationic mixing degree of Li+/Ni2+, illuminating a more orderly structure, smaller particle size and more regular particle shape, which shorten the diffusion length for Li+ ions and allow the rapid kinetics of Li+ ions diffusion. Sure enough, the as‐prepared LiNi1/3Co1/3Mn1/3O2 material displays the first discharge capacity of 208 mAh g−1 and keeps 133 mAh g−1 after 200 cycles between 2.5 and 4.5 V at 0.2 C. In addition, it demonstrates excellent rate capacity of 143 mAh g−1 at 2 C. The results show that LiNi1/3Co1/3Mn1/3O2 prepared by this method has high discharge capacity, admirable rate capability and exceptional cycle stability, which provides significant insights into the synthesis of other layered oxides as cathode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

LiV3O8 material with high discharge capacity has attracted increasing attention as cathode material for lithium‐ion batteries (LIBs). However, LiV3O8 is still limited by its weak dissolution and change of lattice structure. In this study, Mg3(PO4)2 fully coated LiV3O8 nanoparticles are successfully prepared by rheological phase reaction and surface deposition. The thickness of Mg3(PO4)2 coating layer is estimated to 24.7 nm for surface‐modified LiV3O8 with Mg3(PO4)2 content of 1.0 wt.%. The as‐prepared Mg3(PO4)2 coated‐LiV3O8 is utilized as cathode and showed high initial capacity of 323.93 mAh g−1. In addition, it maintained stable capacity of 250.82 mAh g−1 after 50 cycles at the current rate of 60 mA g−1 between 1.8 and 4.0 V. This value was much higher than that of bare LiV3O8. Besides, even at current density of 240 mA g−1, its capacity keeps 170.89 mAh g−1 after 50 cycles. The detailed quantitative kinetics analyses confirm the fundamental reasons behind the enhanced rate capability and cycling stability. Overall, this work opens up novel avenues towards the design of protecting cathode materials, which could broaden applications of insoluble phosphates. Rod‐like Mg3(PO4)2 coated−LiV3O8 were successfully prepared through the rheological phase, then coated by ex‐situ formed Mg3(PO4)2. 1.0 wt.% Mg3(PO4)2 coated sample shows the uniform coated layer with the thickness of 24.7 nm, and delivers a high‐rate capacity of 220.06 mAh g−1 at 240 mA g−1. The detailed quantitative kinetics analyses confirm that surface‐controlled behaviors effectively enhance rate capability and cycling stability. [ABSTRACT FROM AUTHOR]