Search

Summary: Polypyrrole is successfully introduced to enhance the reaction stability and ionic conductivity of LiNi1/3Co1/3Mn1/3O2 material through an ultrasound dispersion method and applied as cathode materials for lithium‐ion batteries. This polymer can significantly advance the electrochemical properties. Expectedly, the 8 wt.% LiNi1/3Co1/3Mn1/3O2/polypyrrole composite has lower mixing degree of Li+/Ni2+, higher c/a value, which delivers the first discharge capacity of 199.2 mAh g−1, which abate to 121.3 mAh g−1 in the 300th cycle at 0.2 C between 2.5 and 4.5 V. Even at 3 C, it continues to reveal a reversible capacity of 86.4 mAh g−1 after 100 cycles. All the consequences implied that the 8 wt.% LiNi1/3Co1/3Mn1/3O2/polypyrrole verified a minor charge transfer resistance and better Li+ diffusion ability, hence establishing preferable rate and cycling performance compared with the primordial LiNi1/3Co1/3Mn1/3O2. [ABSTRACT FROM AUTHOR]

Abstract: Layered Li1.2V3O8 has been efficiently prepared via a sol–gel method. XRD and particle size analysis indicate that the final product with monoclinic structure consists of homogeneously distributed particles whose sizes are in a very narrow range. There are two different water molecules in the compound according to TGA and DTA. The structural water works as a pillar in the structure and is lost at higher temperature than the combined water. The as-prepared material was also compared with the one synthesized from the conventional solid-state method in terms of their morphology, electrochemistry capacity and electrodynamic characteristics. As a result, the Li1.2V3O8 obtained at 300°C for 10h has excellent electrochemical properties. A high-first discharge capacity of 286.4mAh/g was observed at a current rate of C/5 between 1.7 and 3.8V and the structure of Li1.2V3O8 remains stable in the subsequent cycles. EIS calculation suggests a better diffusion path for lithium ions in as-prepared material than in the solid-state compound. [Copyright &y& Elsevier]

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]

Aqueous zinc-ion batteries (ZIBs) with low-priced, high-safety, and high synergistic efficiency have captured an ever-increasing amount of consideration and have been expected to be a promising choice to replace LIBs. However, the cathode materials of ZIBs reported have many shortcomings such as poor electron and zinc ion conductivity and complicated energy storage mechanisms. In this review, several typical cathode materials for ZIBs in recent years and their detailed energy storage mechanisms are summarized, and various improvement methods to enhance the electrochemical properties of ZIBs are briefly introduced. Eventually, the current problems and the expected development foregrounds of ZIBs are proposed. [Display omitted] Although lithium-ion batteries (LIBs) have many advantages, they cannot satisfy the demands of numerous large energy storage industries owing to their high cost, low security, and low resource richness. Aqueous zinc-ion batteries (ZIBs) with low cost, high safety, and high synergistic efficiency have attracted an increasing amount of attention and are considered a promising choice to replace LIBs. However, the existing cathode materials for ZIBs have many shortcomings, such as poor electron and zinc ion conductivity and complex energy storage mechanisms. Thus, it is crucial to identify a cathode material with a stable structure, substantial limit, and suitability for ZIBs. In this review, several typical cathode materials for ZIBs employed in recent years and their detailed energy storage mechanisms are summarized, and various methods to enhance the electrochemical properties of ZIBs are briefly introduced. Finally, the existing problems and expected development directions of ZIBs are discussed. [ABSTRACT FROM AUTHOR]

The recycling of spent lithium-ion batteries (LIBs) is an effectual strategy for mitigating environmental and resource crises. Lithium iron phosphate batteries, renowned for their unique safety and stability, are widely utilized in energy storage systems and electric vehicles, consequently resulting in a growing number of spent LIBs. Herein, a one-pot mechanochemical process that integrates the recycling and preparation of LiFePO4 is proposed to drive the rapid regeneration of spent LiFePO4. Benefiting from the inherent characteristics of the input material, more than 98% of Li is selectively released, while less than 1.5% of Fe is leached without any impurity output. To this end, these reclaimed precursors in a ball mill can be directly re-used for the regeneration of LiFePO4 with an appropriate lithium source addition, eliminating the need to recover LiFePO4 with various degrees of lithium deficiency. As expected, the regenerated LiFePO4 delivers a discharge specific capacity of 143 mA h g−1 without negligible capacity fading after 250 cycles at 1 C, featuring significantly improved rate capability and long-term cycling stability. Designed with sustainable, integrated, and close-loop operation routes, this process pioneers a novel strategy to scale up the direct recycling for the LiFePO4 cathode. [ABSTRACT FROM AUTHOR]

[Display omitted] Carbon materials are promising anode materials for rechargeable lithium and sodium-ion batteries, due to their low cost, high capacity, and structural designability. In this work, we selected a waste biomass, garlic stem, as the carbon precursor, and we systematically investigated the effect of pyrolysis temperature and time on their battery performance. We find that 800 °C and 2 h are the best pyrolysis conditions, which leads to the optimal carbon material (800C-2H) with a large layer spacing, abundant defect sites, high surface area, and sufficient micro/meso-porous structures. Due to these favorable properties, this carbon anode exhibits an impressive performance for Lithium-ion batteries, with a very high capacity of 480 mAh g−1 and no significant capacity fading after 3000 cycles. Besides, this anode also shows promising performance for Sodium-ion batteries, where a good capacity of 151.9 mAh g−1 and reasonable cycling of 100 cycles are achievable. We also carried out in-situ X-ray diffraction and in-situ Raman spectroscopy experiments to understand the relationship between carbon microstructures and their Li-ion storage. [ABSTRACT FROM AUTHOR]

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]

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]

[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]

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]

In this work, it is proved that carbon coated nanospheres structure can effectively enhance the reaction stability, the transmission speed of electrons and ionic conductivity of Sb-based materials. Due to Ni-Co-Sb/C material has the high specific surface area, low charge transfer resistance and special alloying mechanism displayed admirable electrochemical properties as anode materials for LIBs. The synthetic strategy and lithium storage mechanism may provide a new insight into the preparation of high-performance Sb-based electrode materials for LIBs. The strategy of "template sacrifice method" was proposed to synthesize well-defined NiSb/CoSb nanoparticles embedded in carbon nanosphere (Ni-Co-Sb/C, ~560 nm) by calcination treatment of the Ni-Co-MOF (metal-organic framework) precursor. Due to the structural controllability of MOF precursor and Ni/Co bimetallic synergy, the fabricated Ni-Co-Sb/C demonstrates a high surface area (88 m2 g−1) and superior ion conductivity, thus an excellent electrochemical performance as has been achieved as lithium ion battery (LIB) anode. A reversible discharge specific capacity as high as 495.1 mAh g−1 has been stably delivered after 1000 cycles at a high current density of 1.0 A g−1. In addition, the charge transfer impedance of Ni-Co-Sb/C electrode is as low as 67.6 Ω in the 30th cycle at 0.1 A g−1 and the pseudocapacitive contribution is as high as 73.8% at 0.5 mV s−1. The alloying mechanism of Ni-Co-Sb/C has been verified by in-situ X-ray diffraction (XRD), which enables a high lithium storage capacity. Moreover, the full-cell assembled with LiCoO 2 as cathode exhibits a steady discharge specific capacity of 354.0 mAh g−1 at 0.1 A g−1 even after 100 cycles. Our work provides an effective method for the application and high-capacity Sb-based material in energy storage fields, and this material is expected as a promising candidate for a novel anode material in LIBs. [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]

Transition metal oxides/sulfides/selenides (TMOSS), regarded as three of the most potential anode materials for lithium-ion batteries (LIBs), are superior to their low cost, controllable morphology and high theoretical capacity. Herein, a facile strategy, using Ni-MOF material as precursor, was designed to fabricate the unique micro-flower-like NiO, NiS/C and NiSe/C electrodes, including the detailed investigation about their electrochemical and kinetics properties. The results show that sizes of NiO, NiS/C and NiSe/C micro-flowers are around 0.7, 3.5 and 2.0 μm, respectively, which contains abundant micro- and meso-pores. Among them, NiSe/C material exhibits better electrochemical performance when used as anode electrode for LIBs, with high initial capacity (1688.4 mAh g−1 at 0.1 A g−1) and high reversible capacity (1016.5 mAh g−1 at 1.0 A g−1 after 1000 cycles). Moreover, the full-cell, NiSe/C vs. LiCoO 2 , exhibits superior reversible discharge capacities of 421.8 mAh g−1 at 0.1 A g−1 after 50 cycles. It is important that the bond energy of Ni–Se contributes to improving NiSe/C electrochemical performance. This work shows the influence of Li+ insertion and pseudocapacitance behavior on lithium storage performance of TMOSS anode materials, which provides an effective strategy for research and development of TMOSS on LIBs. Image 1 [ABSTRACT FROM AUTHOR]

Summary: Compared with traditional anode materials, spinel‐structured Li4Ti5O12 (LTO) with "zero‐strain" characteristic offers better cycling stability. In this work, by a wet‐chemistry synthesis method, LTO anode materials have been successfully synthesized by using CH3COOLi·2H2O and C16H36O4Ti as raw materials. The results show that sintering conditions significantly affect purity, uniformity of particle sizes, and electrochemical properties of as‐prepared LTO materials. The optimized LTO product calcined at 650°C for 20 hours demonstrates small particle sizes and excellent electrochemical performances. It delivers an initial discharge capacity of 242.3 mAh g−1 and remains at 117.4 mAh g−1 over 500 cycles at the current density of 60 mA g−1 in the voltage range of 1.0 to 3.0 V. When current density is increased to 1200 mA g−1, its discharge capacity reaches 115.6 mAh g−1 at the first cycle and remains at 64.6 mAh g−1 after 2500 cycles. The excellent electrochemical performances of LTO can be attributed to the introduction of rutile TiO2 phase and small particle sizes, which increases electrical conductivity and electrode kinetics of LTO. Therefore, as‐synthesized LTO in this study can be regarded as a promising anode candidate material for lithium‐ion batteries. [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]

Graphical abstract Highlights • ZIF-8 nanocubes are rapidly synthesized and adjusted in aqueous solution. • ZnSe nanoparticles embedded N-doped carbon nanocubes (ZS-NP@NC) are first prepared. • ZS-NP@NC-600 displays high discharge capacity and excellent cyclability. • Kinetics analysis confirms the pseudocapacitive behavior of ZS-NP@NC. Abstract ZnSe is regarded as a promising anode material for reversible Li-ion batteries because of its high theoretical capacity. Herein, we report a facile chemical precipitation method to controllably synthesize ZIF-8 nanocubes and then select them as sacrificial templates to prepare ZnSe nanoparticles embedded N-doped carbon nanocubes. The as-obtained ZnSe/carbon nanocomposite at 600 °C demonstrates a high initial discharge capacity of 1170.8 mAh g−1 with the initial columbic efficiency of 68.8% at the current density of 0.1 A g−1 in the voltage range of 0.01–3 V. In addition, it displays a reversible capacity of 1166.6 mAh g−1 after 500 cycles at the current density of 0.5 A g−1, indicating the excellent cyclic stability for the designed composites. The enhanced electrochemical performance can be ascribed to its high specific surface area (493.45 m2 g−1) and unique mesoporous structure, which provides efficient Li+ transport channels and additional storage sites. Furthermore, the existence of faradaic pseudocapacitance in ZnSe/carbon nanocomposites also affords additional capacity and contributes to the increased capacity with respect to charge/discharge cycle number. [ABSTRACT FROM AUTHOR]

LiV 3 O 8 /poly (3, 4-ethylenedioxythiophene) (LVO/PEDOT) composites were synthesized via an in-situ oxidative polymerization process. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, galvanostatic discharge/charge tests, and electrochemical impedance spectroscopy techniques are used to characterize the as-prepared samples. The results demonstrated that the electrochemical performances of LVO/PEDOT composites have greatly improved in comparison with bare LVO. The discharge capacities of 20 wt% LVO/PEDOT composite are 270, 265, 252, 240, and 229 mAh g − 1 and ˃95% capacity retention is maintained after the charge-discharge 50 cycles at the current densities of 60, 90, 120, 180, and 240 mA g − 1 , respectively. A high reversible capacity of 176 mAh g − 1 (only 58 mAh g − 1 for the bare LVO) can be maintained after 50 cycles at a very high current rate of 2000 mA g − 1 . Electrochemical impedance spectra results implied that the 20 wt% LVO/PEDOT composite revealed a decreased charge transfer resistance and increased Li + ions diffusion ability. This noteworthy improvement is ascribed to the combination of PEDOT, which can act just as a defending layer to inhibit the LVO from direct contact with electrolyte and buffer volume change, and act just as a conductive network to improve the electronic conductivity, thus cycling stability and rate capability are improved. [ABSTRACT FROM AUTHOR]

Conjugated carbonyl compounds with high theoretical capacity, low cost, structural flexibility and abundant resources are potential cathodes in metal-ion batteries (lithium-LIBs, sodium-SIBs, kalium-KIBs). Regrettably, their inherent drawbacks of high solubility and low electrical conductivity limit their further application. Herein, different mass ratios of reduced graphene oxide wrapped poly (1,5-anthraquinonyl sulfide) (PAQS/rGO) composites were prepared through a calcination-treatment process aiming at decreasing the dissolution and enhancing the conductivity. XRD, FTIR and Raman analysis confirmed the successful synthesis of PAQS. XRD analysis also confirmed the conversion of GO to rGO. Four-probe test results showed that the conductivity of composites increased as the rGO ratio increased. SEM images showed that PAQS/rGO composites presented microsphere morphologies. Profiting from the enhanced conductivity and limited dissolution in electrolyte, the PAQS2 (the mass ratios of PAQS and rGO is 10:2) composite exhibited outstanding performance both in half- and full-batteries. In LIBs/SIBs, PAQS2 exhibited reservable discharge capacities of 121 and 115 mAh g−1 at 50 mA g−1 after 200 and 400 cycles, respectively. In PTPAn/PAQS2 all-organic Li/Na-ion batteries, reservable charge/discharge capacities of 42.1/39 and 42.1/40.4 mAh g−1 were retained at 50 mA g−1 after 200 cycles, respectively. Ex-situ FT-IR analysis further performed the redox reaction of carbonyl groups during charging and discharging. [ABSTRACT FROM AUTHOR]

In this study, Ag 2 V 4 O 11 was employed as an additive to boost the electrochemical performance of Li 4 Ti 5 O 12. A series of Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 composites with different Ag 2 V 4 O 11 mass ratios of 3 wt.%, 5 wt.% and 8 wt.% were prepared using liquid-phase dispersion method to yield compounds abbreviated as Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 (3 wt.%), Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 (5 wt.%) and Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 (8 wt.%), respectively. Among them, Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 (5 wt.%) composite displayed a considerable initial discharge specific capacity of 252.4 mAh g −1 at 30 mA g −1 which still maintained at 152.0 mAh g −1 over 500 cycles. At 1200 mA g −1, a capacity of 69.0 mAh g −1 was retained over 5,000 cycles. The electrode kinetic studies revealed that the introduction of Ag 2 V 4 O 11 phase boosted the transport rate of lithium ion and the electronic conductivity of Li 4 Ti 5 O 12. In-situ XRD tests related that Ag 2 V 4 O 11 was decomposed to in situ produce metallic Ag on Li 4 Ti 5 O 12 after cycle. In a word, Li 4 Ti 5 O 12 /Ag 2 V 4 O 11 (5 wt.%) composite was a promising as the electrode material in lithium-ion batteries. The data also provided a fire-new method to enhance the electrochemical property of Li 4 Ti 5 O 12. [ABSTRACT FROM AUTHOR]