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Lithium metal anodes are a key component of high‐energy‐density lithium–sulfur (Li–S) batteries. However, the issues associated with lithium anodes remain unsolved owing to the immature lithium anode construction and protection technology, which leads to internal short circuits, poor capacity retention, and low coulombic efficiency for high‐sulfur‐loading Li–S batteries. Herein, a highly stable 3D lithium carbon fiber composite (3D LiCF) anode for high‐sulfur‐loading Li–S batteries was demonstrated, in which a self‐formed hybrid solid‐electrolyte protection layer was constructed on a lithium metal surface through codeposition of thiophenolate ions and inorganic lithium salts by using diphenyl disulfide as a co‐additive in the electrolyte. The aromatic components from thiophenolate could improve the stability of the protection layer, and the 3D structure of the carbon fiber could effectively buffer the volume effect during lithium cycling. A Li–S battery based on a 3D LiCF anode exhibited excellent cycling stability with an energy efficiency of 89.2 % for 100 cycles in terms of a high energy density of 22.3 mWh cm−2 (10 mAh cm−2 area capacity of lithium cycling). This contribution demonstrates versatile and ingenious strategies for the construction of a 3D lithium anode structure and protection layer, providing an effective solution for practical stable Li–S batteries.

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A hierarchical nanostructure LiFePO4@C composite was fabricated by an oleylamine mediated method. The as-prepared LiFePO4@C electrode shows superior electrochemical performance, especially at low temperature.

NSFC [200933005, 20903077, 21021002]; National 973 Program [2009CB220102]; Key Project Founded by Fujian province [2008H0087]A two-step hydrothermal method is reported here for the synthesis of a sulfur-graphene hybrid material. The scanning electron microscopy, X-ray diffraction and Raman spectroscopy characterizations have confirmed that this method can produce a homogeneous sulfur coating on the graphene surface and prevent the graphene sheets from aggregation simultaneously to form a three dimensional carbon network. When tested as a cathode in lithium sulfur batteries, the hybrid material exhibits a high discharge capacity and good cycling stability at a current density of 1A/g, even as the sulfur content reaches an extremely high level (75.2% wt). Its excellent electrochemical performance can be attributed to the stable carbon skeleton formed by the monolayer graphene sheets and the good contact between sulfur and graphene. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.048208jes] All rights reserved

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Lithium−sulfur (Li−S) batteries have attracted much attention, owing to their high theoretical energy density. Many studies have focused on improving areal sulfur loading by using carbonaceous current collectors. However, low sulfur utilization and polysulfide diffusion could be more severe. Herein, we introduce a reinforced current collector consisting of carbon felt (CF) decorated with carbon nanofibers (CNFs), prepared by using chemical vapor deposition (CVD). The CF@CNFs skeleton shows a large specific surface area for well‐dispersed active materials, highly conductive network with faster electronic/ionic transport, and a micro‐/mesoporous structure for spatial confinement on polysulfides. As a result, the cells with CF@CNFs current collectors exhibit a high specific capacity, superior cycling stability, and a good rate capacity. This work will provide a promising choice for designing novel current collectors toward high‐performance, high sulfur‐loading Li−S batteries.