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Summary: The carbon layer acting as a conductive medium is beneficial to overcoming the comparatively inferior electronic conductivity of Na3V2(PO4)3. Based on this, Na3V2(PO4)3/C composites with diverse ratios of citric acid are synthetized via rheological phase reaction way in this work. The consequences display that the Na3V2(PO4)3/C‐1.5 composite brings a higher initial discharge capacity of 113.2 mAh g−1 at a current rate of 1 C with coulombic efficiency above 99% during all cycles. The discharge capacity retains at 117.6 mAh g−1 at the 100th cycle. Even at the high current densities of 5 C and 10 C, the composite also shows superior cycling performance with negligible capacity fading. Its discharge capacities decline from 97 to 92.6 mAh g−1 at 5 C and from 85.3 to 83.7 mAh g−1 at 10 C. These remarkable outcomes arise from its preferable morphology with suitable carbon coating because both excess and skimpy carbon seriously affect the microstructure and electrochemical properties of Na3V2(PO4)3/C composites. [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]

Summary: Polyaniline‐derived N‐doped carbon‐composited Na3V2(PO4)3 (NVP@NC) are synthesized by a rheological phase reaction followed by calcination. The NVP@NC composite displays improved cycling and rate properties. Its discharge capacity remains 118.7 mAh g−1 at the 400th cycle at 0.3 C. It also obtains invertible capacities of 93.7 and 91.1 mAh g−1 at 5 and 10 C after 1000 cycles, with capacity retention rates of 92.7% and 98.4%, respectively. These enhanced results due to the N‐doped carbon layer (NC), which restrains the expansion and deformation of the crystal structure, reduce the transport length of sodium ion and electrons and improves the electroconductibility of NVP. [ABSTRACT FROM AUTHOR]

Summary: NaV3O8/polytriphenylamine composites were synthesized by an in situ oxypolymerization way for the first time. Among them, the NaV3O8/20 wt.% polytriphenylamine composite shows better cycling and rate performance. Its discharge capacity retains at 118.9 mAh g−1 after 300 cycles at 120 mA g−1. It also obtains a reversible capacity of 101.7 mAh g−1 at 300 mA g−1 after 100 cycles. These enhanced results arise from the excellent morphology, that is, smaller particles of clear edges and uniform distribution suppress the expansion and deformation of the crystal structure, and avoid large agglomerate particles gathering during the electrochemical reaction. In addition, tight polytriphenylamine (PTPAn) coating also improves the conductivity of NaV3O8 cathode and suppresses the dissolution of NaV3O8 in electrolyte. [ABSTRACT FROM AUTHOR]

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]

This paper proposes the new concept of preplanned microgrid islanding (PMI) in the smart distribution system. PMI is a special form of controlled islanding that can be used to provide demand-side service for electrical users under the scheduled distribution operation, especially for the preventive maintenance. A simulation-based multi-objective optimization framework is developed to decide the starting time and duration of PMI. The optimization objectives include the minimization of load curtailment, operating cost, and pollutant emission. On one hand, the stochastic short-term simulation method is developed to assess the performance of candidate PMI schemes considering multiple uncertainties and optimal scheduling of microgrid operation. On the other hand, the weighted-sum approach is used to compromise the conflicting objectives according to the decision preferences of users. Furthermore, the response surface methodology is adopted to improve the efficiency of scheme selection with the help of experimental design technique and regression analysis. Finally, the effectiveness and high efficiency of the proposed method is verified in case studies. Sensitivity analysis is also performed to investigate the impact of decision preference, season scenario, and sizing alternative on optimization result. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]