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A carbon superstructure material (PTA-700) was synthesized by a simple self-assembly method and one-step carbonization, and showed remarkable high energy and long cycle life stability in lithium/sodium ion half battery. [Display omitted] Due to abundant resources and low prices, biomass-derived carbons as anodes for lithium ion batteries (LIBs) and sodium ion batteries (SIBs) have been widely reported. However, it is still a challenge to design a biomass-derived carbon material that has immunity to environmental influences, stable chemical composition and controllable morphology. In this paper, tannic acid (TA) as a precursor is first reported to synthesize rod structures with abundant mesopores and defects (PTA-700). These features can provide more active sites and space for lithium and sodium ions storage, which is conducive to lithium and sodium ions transfer. Excellent electrochemical performance is observed in LIBs (535 mAh/g after 100 cycles at 0.1 A/g) and SIBs (114.0 mAh/g after 3000 cycles at 1 A/g). Kinetics analysis and density functional theory (DFT) calculations were carried out to further analyze the superior lithium and sodium ions storage performance of PTA-700. More importantly, PTA-700 solves many problems faced by traditional biomass-derived carbons in commercialization. Our work suggests an effective way to develop high-performance biomass-derived carbon anode materials for LIBs and SIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Polymer materials containing C 6 rings and C O become promising electrode materials for high-performance lithium ion batteries (LIBs). However, the poor electronic conductivity severely restricts its further application. Herein, we design and construct a pyromellitic dianhydride anhydride anthraquinone/reduced graphene oxides (PMAQ/rGO-40) composite as an anode material for LIBs. The PMAQ is uniformly wrapped by conductive rGO nanosheets. The PMAQ/rGO-40 electrode without additional conductive agents displays a discharge capacity of 253 mAh g−1 over 3000 cycles under 2A g−1, which is higher than that of the PMAQ electrode with conductive agents. Meanwhile, a capacity of 196 mAh g−1 is achieved under 5A g−1. The enhanced cycling performance and rate ability are attributed to the rGO conductive network, which promotes electronic transport capability. In addition, the lithium ion storage mechanism and kinetics in the PMAQ/rGO-40 are investigated. The excellent electrochemical performance shows the potential application of the PMAQ/rGO composite anode material for high performance LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] The effect of the chemical component and microstructure, not to mention their facile modification, of the coating/wrapping carbon layer on the electrochemical performance of the Si/C composite anode in lithium ion batteries (LIBs) hasn't been actively explored although Si/C has been recognized as one of the most promising route for the high energy density LIBs. Herein we propose a novel nitrogen-plasma doping route to modify the top carbon film in an elaborately constructed layered Si/C composite anode. The electrochemical performance, e.g., the initial coulombic efficiency (CE), cycle stability and specific capacity of the composite anode is drastically improved by this plasma processing due to the increased kinetics of lithium ions. By means of the appropriate adjustment of the N doping ratio and N chemical configuration in the carbon layer through a N 2 /H 2 plasma processing, the lithium diffusion rate in the composite anode was memorably increased as the pseudocapacitance effects promoted. The optimized Si/C composite exhibits a high capacity of 1120.7 mA h g−1 and an initial CE of 80.8% at the current of 2 A g−1 after a long cycle of 1500, increasing by ~40% of specific capacity and ~29% of the initial CE. [ABSTRACT FROM AUTHOR]

CaMnO 3 , a perovskite-type material, has been introduced as a novel anode material for lithium ion batteries, and its electrochemical performance at different temperatures is systematically investigated. The as-prepared CaMnO 3 material exhibits a high specific capacity, favorable rate performance and excellent cycling stability. The CaMnO 3 anode could deliver a high specific capacity of 102.5 mAh g-1 after 500 cycles at a current rate of 0.1 A g-1. Lithium ion batteries are attracting ever increasing attention due to their advantages of high energy/ power density, environmental friendly, lifetime and low cost. As a star in the field of materials and energy, perovskites have received extensive attention due to their attracting physical and chemical properties. Herein, CaMnO 3 , one material from the perovskite family is introduced as a novel anode material for lithium ion batteries, and its electrochemical performance at different temperatures is systematically investigated. CaMnO 3 has been synthesized using a liquid phase synthesis method followed by high temperature calcination. The as-obtained CaMnO 3 exhibits an initial high discharge capacity of 708.4 mAh g−1, superior rate capability and stable cycling performance at room temperature, the specific capacity is 102.5 mAh g−1 after 500 cycles at a current density of 0.1 A g−1. Additionally, at an extreme temperature of 0 °C, the discapacity can reach 138.2 mAh g−1 at a current density of 0.05 A g−1. At high temperature of 50 °C, the reversible discharge capacity is up to 216.5 mAh g−1under the same condition. It is believed that this contribution may lay the foundation for the application of perovskites in other rechargeable batteries and energy storage devices. [ABSTRACT FROM AUTHOR]

Hierarchical porous chromium niobium oxide (Cr 0.5 Nb 24.5 O 62) microspheres are prepared by a facile one-step solvothermal method and demonstrated with noticeable lithium ion storage performance with superior high-rate capability (199 mAh g−1 at 20C) and good cycling stability. • Construct hierarchical porous Cr 0.5 Nb 24.5 O 62 microspheres as anodes. • Hierarchical porous Cr 0.5 Nb 24.5 O 62 microspheres show high capacity. • Hierarchical porous structure is favorable for fast ion/electron transfer. Controllable fabrication of advanced electrode materials is critical for the development of lithium ion batteries (LIBs). Herein, for the first time, we report novel hierarchical porous chromium niobium oxide (Cr 0.5 Nb 24.5 O 62) microspheres prepared by a facile one-step solvothermal method. The as-prepared Cr 0.5 Nb 24.5 O 62 microspheres present 3D hierarchical porous structure consisting of cross-linked nanoparticles, high electronic conductivity and large specific surface area. Accordingly, the Cr 0.5 Nb 24.5 O 62 microspheres show noticeable lithium ion storage performance with superior high-rate capability (199 mAh g−1 at 20C) and good cycling stability with a capacity retention of 95% over 1000 cycles, much better than the bulk Cr 0.5 Nb 24.5 O 62 and TiNb 24 O 62 counterparts. Our work demonstrates a new high-rate electrode material for high-power energy storage. [ABSTRACT FROM AUTHOR]