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High energy-storage Li-ion battery needs a high-capacity anode. However, current graphite-based anode doesn't meet this requirement, thus developing high performance anode materials is highly needed and significant. Here, we provide a rational engineering of a multi-layered hollow structure combining with surface coating of polyamine (PANI) layer, forming a Co 3 O 4 /NiO@PANI hybrid using for Li-ion battery anode. PANI is able to effectively improve the conductivity of active materials; besides, PANI is flexible, which can prevent the collapse of the structure caused by volume-expansion during charge and discharge. The multi-layered morphology improves the utilization ratio of voids inside the conventional hollow structured materials, which is significant to improve capacity in practical applications. The Co 3 O 4 /NiO@PANI hybrid-based anode shows a capacity of 1049 mAh g−1 along with a Coulombic efficiency of 99.3% after 100 cycles of 0.2 A g−1. Rate-performance of Co 3 O 4 /NiO@PANI exceeds that of the bare Co 3 O 4 /NiO. It is believed that the hierarchical structure combining multi-layered hollow morphology with surface coating of conductive polymer presented here would find broad applications for developing high-performance energy-storage hybrids. [Display omitted] • A novel Co 3 O 4 /NiO@polyamine is developed for Li-ion battery anode. • Polyamine nanorods on Co 3 O 4 /NiO keep robust during cycling. • Co 3 O 4 /NiO@polyamine anode exhibits a high and stable capacity. • A recoverable rate-performance of Co 3 O 4 /NiO@polyamine is achieved. [ABSTRACT FROM AUTHOR]

Nano-engineering graphene-based composite anodes have motivated broad investigations of the high energy density lithium-ion batteries. Here, a sandwich-like and porous NiCo 2 O 4 @reduced graphene oxide (rGO) nanocomposite was presented. Through an incipient dipping process, the NiCo 2 O 4 precursors attach on the rGO densely, which significantly improves the material loading of the NiCo 2 O 4 @rGO composites. Serving as an anode of the lithium-ion battery, the NiCo 2 O 4 @rGO composites exhibit an unprecedented capacity of 1566 mAh g −1 cycling at a current density of 1000 mA g −1 over 700 times; while a capacity of 886 mAh g −1 at 100 mA g −1 over 100 cycles was achieved upon a NiCo 2 O 4 @rGO//LiCoO 2 full-cell, which indicates a promising potential for high energy density battery applications. [ABSTRACT FROM AUTHOR]

• A novel multi-layered SnO 2 @NiMoO 4 composite is developed for Li-ion battery anode. • The dense NiMoO 4 nanosheets on SnO 2 shorten the Li-ion transfer pathways. • SnO 2 @NiMoO 4 anode exhibits a high capacity. • A well-recoverable rate-performance is achieved. [Display omitted] High-performance anodes are highly needed for lithium-ion batteries to achieve high capacity and energy density. Here, a strategy of combining hollow yolk-shell structure and surface modification is reported to improve the capacity of anode. As a demonstrating case study, a nanosheets-coated multiple-layered SnO 2 @NiMoO 4 composite is prepared through a simple hydrothermal method. The results show that the multilayered SnO 2 microspheres and NiMoO 4 nanosheets would exhibit a synergistic effect, which efficiently improves the electrochemical properties of Li-ion battery anode. During the cycling, the hollow multilayered SnO 2 microspheres coated by NiMoO 4 nanosheets maintain a robust structure, and have a long cycle life. The reversible capacity of SnO 2 @NiMoO 4 anode is as high as 1109 mAh g−1 at 400 mA g−1 for 250 cycles, which is competitive to the bare SnO 2 and some other reports, indicating a potential for developing high-performance Li-ion battery systems. [ABSTRACT FROM AUTHOR]

• A binder-free composite cathode is developed for Li-S batteries. • Stable capacity and recoverable rate-performance are achieved. • Density functional theory calculations show the composite has large binding energies with polysulfides. • Three-dimensional composite facilitates ion diffusion and electron transport. [Display omitted] A binder-free porous graphene like-C 3 N 4 nanoflakes/carbon cloth/sulfur lithium-sulfur battery cathode prepared through a thermal polymerization method is presented. On the basis of the density functional theory calculations on the bonds between g-C 3 N 4 and lithium polysulfides including Li 2 S 4 , Li 2 S 6 and Li 2 S 8 , it is found the cathode possesses robust binding energies towards polysulfides and an improved conductivity, which would enable a strong suppression for the transfer of the lithium polysulfides. The prepared porous binder-free cathode exhibits a high capacity of 892 mAh g−1 after cycling 250 times at 0.2 C and a well-recoverable rate-performance, which indicates a good potential to construct high-performance lithium-sulfur batteries for practical applications. [ABSTRACT FROM AUTHOR]

Hierarchical materials have been considered promising for secondary battery electrodes owing to their capability of accommodating volumetric change of active materials and providing short pathways for rapid transportation of ions and electrons. Herein, we present a rod-on-tube composite consisting of cobalt molybdate (CoMoO 4) nanotubes coating with polyaniline (PANI) hydrogel nanorods, which exhibits a high electrochemical performance as Li-ion battery anode. The hierarchical CoMoO 4 @PANI is prepared through in-situ polymerizing PANI nanorods on the CoMoO 4 nanotubes. The rod-on-tube structure could alleviate the volumetric change of CoMoO 4 during lithiation-delithiation, and improve conductivity for electron transfer. When cycling at 0.5 A g-1, the presented CoMoO 4 @PANI anodes exhibit a large capacity of 805 mAh g-1 after 150 cycles along with a Coulombic efficiency of 99%, which are both exceeding those of the pristine CoMoO 4. A well-recoverable rate-performance is achieved. Furthermore, the density of state (DOS) and band gap of the CoMoO 4 @PANI and pristine CoMoO 4 are also investigated by using density functional theory (DFT) calculations. Image 1 • A rod-on-tube CoMoO 4 @hydrogel composite anode is presented. • Rod-on-tube structure enables rapid transportation of ions and electrons. • CoMoO 4 @hydrogel composite exhibits a high electrochemical performance. • Density function theory calculations verify an improved conductivity. [ABSTRACT FROM AUTHOR]