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A comprehensive and scientific research experiment based on the solution combustion method is designed to prepare niobium pentoxide (Nb2O5) for high-rate lithium storage. The phase and morphology of the samples are analyzed by X-ray diffraction and scanning electron microscopy. The electrochemical performance of the Nb2O5 anode is investigated by galvanostatic charge-discharge measurements, and the pseudo capacitance behavior is explored by cyclic voltammetry (CV) technique. The results indicate that H-Nb2O5 obtained at 950 °C exhibits optimal lithium storage performance, demonstrating a reversible specific capacity of 104 mAh/g at an ultra-high current density of 100 C. This comprehensive experiment design is simple and covers the knowledge points of synthesis, characterization, and electrochemical performance, which is convenient for students to understand the relationship between the structure and performance of the materials. Furthermore, it also boosts their awareness of scientific research innovation and comprehensive practical skills. [ABSTRACT FROM AUTHOR]

Niobium-based oxides are considered to be promising anode materials for lithium-ion batteries (LIBs) due to their high capacity, excellent cycling performance and desirable safety. However, the poor intrinsic conductivity and relatively sluggish reaction kinetics limit its broad applications. Herein, V5+ was in situ doped into W3Nb14O44 using a solution combustion method. It was found that V5+ doping did not destroy the intrinsic Wadsley–Roth crystal structure of W3Nb14O44. Instead, it led to a reduction in both the cell volume and material size, which was convenient for the contact between the electrode material and the electrolyte, increased the number of reaction sites and shortened the Li+ transport path. Meanwhile, the EIS and CV results demonstrate that the doping of V5+ is beneficial to improve the electronic conductivity and Li+ diffusion coefficient of the materials. Consequently, microsized W3V0.28Nb13.72O44 exhibits superior electrochemical properties, including an outstanding rate capability of 144.17 mA h g−1 at 100 C and excellent cyclic stability with a capacity retention of 80.29% after 500 cycles at 5 C. In addition, the LiFePO4//W3V0.28Nb13.72O44 full cell also exhibits good cycling stability over 800 cycles at 10 C with tiny capacity loss of only 0.02% per cycle. This work provides a general approach for the design and development of low-conductivity electrode materials for fast Li+ storage. [ABSTRACT FROM AUTHOR]

Ti2Nb10O29 is fabricated directly by solid-state reaction from commercial TiO2 and Nb2O5. Without further modification, the bulk Ti2Nb10O29 anode exhibits a reversible capacity of 144 mAh g-1at 10 C after 800 cycles. More impressively, the capacity of the Ti2Nb10O29/LiFePO4 full-cell at 1 C stabilizes at 100 mA h g-1 after 1000 cycles. [ABSTRACT FROM AUTHOR]

A new thread for improving the cycling stability of Fe2O3 nanorice is proposed through combining the electrochemical porousness (EP) effect and solid-electrolyte interphase (SEI) thermolysis approach. Starting from solid Fe2O3 nanorice, this process could be applied to prepare porous Fe2O3 nanorice with a good coating of a porous SEI thermolysis layer composed of carbon and Li2O. The interconnecting pores and full coating of the SEI thermolysis layer provides not only mechanical resistance of the Fe2O3 nanorice against pulverization, but also high electrical and ionic conductivity over the electrode throughout long cell cycles. This method results in the enhancement of cycling ability and capacity, which is demonstrated by comparison with the starting Fe2O3 nanorice. After the EP and SEI thermolysis approach, the Fe2O3 nanorice exhibits an energy capacity retention about of 680 mAhg-1 at a current density of 1000 mAg-1 over 250 cycles, which is more than 82% of the initial reversible capacity. Moreover, it also has an excellent rate capability and high coulombic efficiency. This strategy provides a simple and convenient route toward stable charge/discharge cycling for not only Fe2O3, but also for other electrode materials that are subject to large volume changes and low charge voltages. At the same time, it also contributes to a fundamental understanding of improved cycling stability and reversible capacity for electrode materials. [ABSTRACT FROM AUTHOR]

A new family of sulfur-rich phosphorus sulfide molecules (P 4 S 10+n ) and their electrochemical reaction mechanism with metallic Li has been explored. These P 4 S 10+n molecules are synthesized by the reaction between P 4 S 10 and S. For Li batteries, the P 4 S 40 molecule in the series of P 4 S 10+n molecules provides the highest capacity, which has a first discharge capacity of 1223 mAh g -1 at 100 mA g -1 and stabilizes at approximately 720 mAh g -1 at 500 mA g -1 after 100 cycles. This new class of sulfur-rich P 4 S 10+n molecules and its electrochemical behavior for room-temperature Li + storage could provide novel insights for phosphorus sulfide molecules and high-energy batteries., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new thread for improving the cycling stability of Fe 2 O 3 nanorice is proposed through combining the electrochemical porousness (EP) effect and solid-electrolyte interphase (SEI) thermolysis approach. Starting from solid Fe 2 O 3 nanorice, this process could be applied to prepare porous Fe 2 O 3 nanorice with a good coating of a porous SEI thermolysis layer composed of carbon and Li 2 O. The interconnecting pores and full coating of the SEI thermolysis layer provides not only mechanical resistance of the Fe 2 O 3 nanorice against pulverization, but also high electrical and ionic conductivity over the electrode throughout long cell cycles. This method results in the enhancement of cycling ability and capacity, which is demonstrated by comparison with the starting Fe 2 O 3 nanorice. After the EP and SEI thermolysis approach, the Fe 2 O 3 nanorice exhibits an energy capacity retention about of 680 mAh g -1 at a current density of 1000 mA g -1 over 250 cycles, which is more than 82 % of the initial reversible capacity. Moreover, it also has an excellent rate capability and high coulombic efficiency. This strategy provides a simple and convenient route toward stable charge/discharge cycling for not only Fe 2 O 3 , but also for other electrode materials that are subject to large volume changes and low charge voltages. At the same time, it also contributes to a fundamental understanding of improved cycling stability and reversible capacity for electrode materials., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)