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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]

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]

Recycling of spent lithium-ion batteries (LIBs) has emerged as an inevitable trend in promoting environmental sustainability and resource conservation. Lithium iron phosphate (LiFePO 4 or LFP) battery, renowned for its unique stability and favorable price, has been the predominant focus for lithium-ion battery manufacturers, consequently resulting in a surge in the number of spent LIBs. In view of the failure mechanism, the direct regeneration technology presents a potential strategy for the closed-loop recycling of LFP. The aim is to retain the high added value and revitalize optimal state of the spent cathode materials through a non-destructive process that maximizes efficiency and ensures desirable profits. Hence, the existing technical challenges and recent progress in the separation pretreatment are reviewed and summarized. Subsequently, the current direct regeneration methods and advanced upcycling techniques for spent LFP cathode are outlined, along with an appraisal of their respective advantages and disadvantage. Specifically, a comprehensive analysis of environmental and economic benefits derived from three presentative examples is highlighted compared to traditional metallurgy process. The review also aims to provide an overview on direct regeneration of spent LFP cathode, making it favorable for further industry adoption. • Potential strategy for low-value LFP via direct regeneration is presented. • Challenges and recent progress in separation pretreatment are discussed. • Recent advancements and advanced upcycling for spent LFP cathode are summarized. • The merits and drawbacks of each approach are assessed. • The comprehensive analysis of environmental and economic benefits is emphasized. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work summarizes the application of vanadium oxides as aqueous ZIBs cathodes. • Electrochemical properties and energy storage behavior of different types of vanadium oxide cathodes. • Current challenges and expected development foregrounds of vanadium oxides cathodes in aqueous ZIBs are proposed. The rapid development of science and technology, as well as the trend toward intelligence, has resulted in a surge in the demand for excellent energy storage devices for smart devices. At present, the most widely used lithium ion batteries have limited further development because of their high cost and various disadvantages of electrolytes (flammable and toxic). In spite of the low costs and safety of aqueous zinc-ion batteries, the high radius of the zinc ions and strong electrostatic interactions make cathode materials without excellent performance difficult to find. Various oxidation states, structural diversity, excellent multiplicity performance and high capacity have attracted researchers to vanadium-based oxides in recent years. However, vanadium-based oxides have disadvantages such as poor structural stability and low electrical conductivity, so this paper summarizes the progress of research on vanadium oxide cathode materials such as V 2 O 5 , VO 2 , V 2 O 3 , etc., and provides an outlook on future development directions. [ABSTRACT FROM AUTHOR]

Abstract A series of LiNi 1/3 Co 1/3 Mn 1/3 O 2 /polytriphenylamine composites were successfully synthesized by ultrasound dispersion method. LiNi 1/3 Co 1/3 Mn 1/3 O 2 /polytriphenylamine (5.0 wt%) composite with small and homogeneous particle size exhibited excellent electrochemical performance, which delivered an initial discharge capacity of 223.7 mAh g−1 with a capacity retention of 84.39% after 100 cycles in the voltage range of 2.5–4.5 V and at a current density of 0.2C. Moreover, an excellent specific discharge capacity of 127.3 mAh g−1 at a current density 5C indicates a superior rate performance of the LiNi 1/3 Co 1/3 Mn 1/3 O 2 /polytriphenylamine (5.0 wt%) composite. The good electrochemical performances of the composite can be attributed to the introduction of polytriphenylamine, which increased electrical conductivity, decreased charge transfer resistance and increased Li+ ion diffusion ability. These noteworthy results demonstrated that LiNi 1/3 Co 1/3 Mn 1/3 O 2 /polytriphenylamine composites might be potential cathode materials for lithium ion batteries. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

LiV 3 O 8 /10 wt% poly(1,5-diaminoanthraquinone) composite was prepared by a in situ chemical oxidative polymerization process and applied as cathode material for rechargeable lithium batteries. Due to the introduction of poly(1,5-diaminoanthraquinone) and electrochemical synergistic effect, the composite demonstrated better rate capabilities and cycling performances compared to the bare LiV 3 O 8 sample. [ABSTRACT FROM AUTHOR]

The development of lithium-ion batteries is hindered by the lack of appropriate low-cost cathode materials with high performance. Here, the preparation of Cu-coated Li 3 V 2 (PO 4) 3 /C (x % Cu-LVPC) composites is reported via a chemical precipitation and self-reduction method. With an optimized Cu coating content of 2.0 wt%, the 2.0% Cu-LVPC composite displays the best electrochemical properties. The initial discharge capacity of 2.0% Cu-LVPC is 175 mA h g−1 at 0.15 C (30 mA g−1) in the voltage range from 3.0 to 4.8 V and the capacity retention is 86.3% after 50 cycles, whereas pristine LVPC has an initial capacity of 163 mA h g−1 and retains 82.2% of the capacity after 50 cycles. Moreover, the rate capacity of 2.0% Cu-LVPC is also increased under different current densities and 2.0% Cu-LVPC exhibits excellent long-term cycling performance of 89 mA h g−1 after 1000 cycles at 10 C. The enhanced electrochemical properties are attributed to the uniform coating of the metal conductor Cu on the LVPC surface, which is conducive to electron transfer and extraction/insertion of Li+ ions. • Cu-coated Li 3 V 2 (PO 4) 3 /C (LVPC) was prepared via a chemical precipitation and self-reduction method. • The 2.0% Cu-coated LVPC composite exhibits significantly improved electrochemical performance. • Cu coating can effectively increase the conductivity of LVPC. • Cu coating on the surface of LVPC can reduce the polarization. [ABSTRACT FROM AUTHOR]

• LZO-LVPC composites were prepared by a simple mechanical ball-milling method. • 4.0 wt% LZO-LVPC exhibit a significant improved electrochemical performance. • LZO compensate for the transfer of Li+ between the cathode material and the electrolyte. • LZO protect the cathode material from side reactions with electrolyte. A simple and efficient synthetic route was developed to obtain composites by mechanically ball-milling Li 2 ZrO 3 (LZO) with Li 3 V 2 (PO 4) 3 /C (LVPC). LZO improves the ionic conductivity of LVPC, compensates for the transfer of Li+ between the LVPC and the electrolyte, reduces the impedance of LVPC, and protects LVPC from side reactions caused by direct contact with the electrolyte. The composite consisting of 4.0 wt% of LZO exhibited a considerable electrochemical performance. The 1st discharge capacity reached 192 mAh g−1 at 30 mA g−1 between 3.0 and 4.8 V, and remained at 153 mAh g−1 after 50 cycles. The EIS analysis showed that the charge transfer and diffusion of Li+ in the LZO-LVPC composites were more favorable than those of pristine LVPC. The synthetic method proposed in this work is simple and efficient, which is convenient for large-scale production. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have garnered significant academic and industrial focus because of their excellent merits, like high voltage, high energy density, excellent cyclic performance, no memory effect and environment-friendly nature. So far, the electrochemical properties of LIBs are restricted by the capacity of cathode materials and various novel compositions and designed architectures have been proposed to enhance the energy density and cyclic performance of LIBs cathodes. Recently, lithium nickel cobalt manganese oxides have attracted extensive research interest owing to the united advantages of LiCoO 2 , LiNiO 2 and LiMnO 2. Herein, we have reviewed the recent developments of LiNi 1/3 Co 1/3 Mn 1/3 O 2 from the viewpoint of synthesis processes and structural designs. The electrochemical properties of LiNi 1/3 Co 1/3 Mn 1/3 O 2 depend on particle size, morphology, ion doping and surface coating of the as-prepared cathode powder. The present article summarizes the recent developments and provides an insight into the future roadmap for the realization of high energy density LIBs. • Main synthesis methods of NCM cathodes are summarized and analyzed. • Partial ionic substitution enhances the structural stability and electronic conductivity. • Surface coating can prevent the side reactions, improved the electronic and ion migration rate. • Composite structure can increase the structure constancy and the electronic conductivity. [ABSTRACT FROM AUTHOR]

• Substitution ions can affect the lattice constants, grain size and morphology. • Doping sites include Li, V, O sites, cation and anion co-doping, interlayer doping. • Ions-doping improves the diffusion coefficient and the electronic conductivity. • Ions-doping is an important trend for the long-term development of Li 1+ x V 3 O 8. Compared with other materials, monoclinic Li 1+ x V 3 O 8 as the promising cathode includes many strong points, such as high theoretical capacity, abundant raw materials, safety characteristic and low environmental impact. However, the primary problems facing the development of Li 1+ x V 3 O 8 for energy storage devices are poor cycling performance, low rate capability and short service life. Recently, many researches have taken various measures to overcome these shortcomings. In this mini-review, we summarized the recent developments of Li 1+ x V 3 O 8 and focus on the improving of Li 1+ x V 3 O 8 by ions-doping, which is deemed to a significant manner to improve the electrochemical performances of Li 1+ x V 3 O 8. [ABSTRACT FROM AUTHOR]