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Abstract: The development of lithium (Li) metal anodes Li metal batteries faces huge challenges such as uncontrolled Li dendrite growth and large volume change during Li plating/stripping, resulting in severe capacity decay and high safety hazards. A 3D porous copper (Cu) current collector as a host for Li deposition can effectively settle these problems. However, constructing a uniform and compact 3D porous Cu structure is still an enormous challenge. Herein, an electrochemical etching method for Cu–Zinc (Zn) alloy is reported to precisely engrave a 3D Cu structure with uniform, smooth, and compact porous network. Such a continuous structure endows 3D Cu excellent mechanical properties and high electrical conductivity. The uniform and smooth pores with a large internal surface area ensures well dispersed current density for homogeneous Li metal deposition and accommodation. A smooth and stable solid electrolyte interphase is formed and meanwhile Li dendrites and dead Li are effectively suppressed. The Li metal anode conceived 3D Cu current collector can stably cycle for 400 h under an Li plating/stripping capacity of 1 mA h cm−2 and a current density of 1 mA cm−2. The Li@3D Cu||LiFePO4 full cells present excellent cycling and rate performances. The electrochemical dealloying is a robust method to construct 3D Cu current collectors for dendrite‐free Li metal anodes. [ABSTRACT FROM AUTHOR]

In order to achieve a high capacity and capacity retention of Ge-based Lithium-ion batteries, it is critical to identify a scalable and economical method to prepare Ge-based materials. We present a mean of preparation and characterization for GeO 2 /SnO 2 (GS) nanofibers produced by electrospinning technique. The optimized GS nanofibers (Ge/Sn mol ratio is 0.88) shows a high initial reversible capacity of 922 mA h g −1 and excellent cyclability (charge capacity retention is 73.9%). [ABSTRACT FROM AUTHOR]

Abstract: Uniform hierarchical SnS2 structures were synthesized by a facile solvothermal approach. Based on time-dependent experiments results, a possible formation mechanism of the hierarchical SnS2 architectures was proposed. Mesoporous hierarchical SnO2 also could be obtained by calcining the corresponding SnS2 structures. When used as the anode materials of rechargeable lithium-ion batteries, both of them showed high specific capacities and enhanced rate capacities. [Copyright &y& Elsevier]

Urchin-like nano/micro-structured FeO/C composite has been successfully synthesized using inexpensive starting materials. The urchin-shaped nano/micro-structure consisted of several oriented nanorods. TEM analysis revealed that there is a large number of pores and uniform amorphous carbon distribution at a nanoscale in the nanorods walls. As used in lithium-ion batteries, the mesoporous FeO/C anode delivered a higher reversible capacity of about 830 mAh g at 0.1 C up to 50 cycles, as well as enhanced high-rate capability compared with urchin-like FeO and commercial FeO. The improvements can be attributed to the combined effects of the nano/micro-architecture, the porosity, and the ultra-fine carbon matrix, where the three factors would contribute to possess both the merits of nanometer-sized building blocks and micro-sized assemblies and provide high electronic conductivity. It is believed that the results of this study offer new prospects for improving the lithium storage capacity of metal oxides by controlling both architecture and composition. [ABSTRACT FROM AUTHOR]

Abstract: Ni foam suppported-SnO2 nanorod arrays with controllable diameter were prepared via a template-free growth method, which was a convenient route for the large-scale growth of pure-phase metal oxide nanorod arrays on metal substrates. The relationship between electrochemical behavior and the shape of SnO2 nanorod arrays has been investigated in detail. SnO2 nanorod arrays with diameter of about 25nm, as anode materials for Li-ion batteries revealed a capacity of 607mAh g−1 (at 0.2 C) up to 50 cycles. The superior performance of the SnO2 nanorods can be mainly attributed to small size of nanorods which reduce volume expansion and lithium diffusion length. [Copyright &y& Elsevier]

Abstract: In this work, three-dimensional mesoporous NiO nanostructures have been synthesized by a simple ethylene glycol (EG)-mediated self-assembly route and subsequent calcination process. The synthesized nickel alkoxide precursors annealed at 300 and 500°C exhibit different surface area, crystallinity and pore distribution, which have been characterized by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, X-ray diffraction, Fourier transform infrared spectroscopy and Nitrogen adsorption/desorption isotherms. The electrochemical properties of these NiO mesoporous nanostructures are investigated including the cycling and rate performance as anode materials for lithium-ion batteries. It is indicated that mesoporous NiO nanospheres synthesized at 500°C exhibit better electrochemical performance than that obtained at 300°C. The NiO nanospheres annealed at 500°C present a reversible specific capacity of 518mAhg−1 at a current density of 0.1Ag−1 after 60 cycles. With varying the rate from 0.1 to 8.0Ag−1, the capacity remains at 535mAhg−1 at 2Ag−1 after 30 cycles and resumes to 582mAhg−1 at 0.1Ag−1 after 60 cycles. The results indicate that our mesoporous NiO nanospheres are promising anode materials for lithium ion batteries. [Copyright &y& Elsevier]