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SiO x is proposed as one of the most promising high-performance anodes for its favorable capacity and stable lithium insertion/extraction electric potential, however its effective commercial application still faces giant challenge. To overcome poor electrical conductivity and huge volume effect of silicon oxide-based material, we adopt a valid strategy to synthesis the SiO x nanosphere double-wrapped by MoS 2 and multi-walled carbon nanotubes (CNTs) as anode material. The influences of MoS 2 and CNTs on the structure, morphology and electrochemical performances of nanohybrid are probed detailly by transmission electron microscopy, X-ray photoelectron spectroscopy and charge-discharge measurements. The results show that as-prepared nanohybrids release a steady reversible capacity of 798 mAh g−1 with high capacity retention of 81.4% at 500 mA g−1 after 300 cycles. The outstanding electrochemical properties can be ascribed to the facts that the hollow mesoporous structure affords ample buffer space and the introduction of MoS 2 with a two-dimensional layered structure can provide more exposed active-sites for lithium adsorption, as well as the CNTs wrapping can form a favorable conductivity matrix, endowing the nanocomposites with great structural stability. Accordingly, this new structure design by means of a heterogeneous dual-wrapped architecture develops a significant strategy for the development of high-performance SiO x -based anode materials. Unlabelled Image • Heterogeneous dual-wrapped architecture of SiO x /MoS 2 -CNTs is successfully prepared. • The hollow structure shortens the transportation of Li+/e− and offers buffer space. • Wrapping MoS 2 can own more exposed active sites for promoting transport of Li+/e−. • The conductive twining CNTs form a favorable conductivity framework. • The material presents excellent cycling performance and rate capability. [ABSTRACT FROM AUTHOR]

• Graphite was regenerated by acid leaching and graphene-like carbon coating. • The structure defects of graphite are well repaired. • The graphene-like carbon layer improves electrochemical performance of graphite. • The recycled graphite can meet the standard of commercial material. The recycling of waste electrode materials from spent lithium-ion batteries (LIBs) is attracting widespread attention from the perspective of the reutilization of resources and environment protection. Nevertheless, the low added value, complex separation steps and the structure defects induced in the long-term charge/discharge process reduce people's interest for secondary utilization of waste graphite anode. More importantly, if waste graphite anode is not prudently treated, it will cause black pollution. Herein, we report a facile and efficient graphene-like coating strategy for the regeneration of waste graphite. Using low-cost Humic Acid as the coated carbon source and waste graphite as the core, graphene-like-coated graphite anode material was prepared by sulfuric acid leaching and in situ carbonization of Humic Acid. Humic Acid containing aromatic rings can be in-situ converted to a graphene-like coating layer to repair the surface defects of graphite during thermal treatment, which can effectively restore the Li+ transport channels, improve the rate performance and cycle stability of the reconstructed graphite anode. When it is reused as anode material of LIBs, the reconstructed graphite anode shows a high initial Coulombic efficiency of 86.2 %, high capacity of 352.76 mAh/g and good retention capacity rate of 86.7 % after 400 cycles at 0.5C. Therefore, the graphene-like coating strategy provides a significant exploration for the recycling and regeneration of waste graphite anode materials, and it is conducive to the realization of the carbon peaking and carbon neutrality goals. [ABSTRACT FROM AUTHOR]

SiO x has aroused great attractions as a promising substitute for the anode materials of high-performance lithium-ion batteries (LIBs) because of the high specific capacity and the longer cycle life as well as relatively low volume expansion compared to Si. However, the unstable structure and poor conductivity of the SiO x lead to unideal electrochemical properties in LIBs, and thus hindering the widespread application of the SiO x anode. Herein, a facile approach has been put forward to prepare the high-performance mesoporous structure SiO x /carbon (m-SiO x /C) composites by electrospinning technique and sintering processes. The spherical SiO x nanoparticles are well anchored on the carbon fibers, and the reserved space can accommodate large volume expansion of the SiO x materials. Besides, the fibrous carbon materials can significantly enhance the conductivity for the SiO x anodes. Therefore, the resultant m-SiO x /C composites exhibit high discharge specific capacity of 1434 mAh g−1 at 500 mA g−1 with 67.5% capacity retention after 500 cycles and the good rate properties of 410 mAh g−1 at 2000 mA g−1. In consequence, the reasonable structural design and innovative fabrication technique can facilitate the practical application for the m-SiO x /C composites and further promote the comprehensive electrochemical performance of LIBs. [ABSTRACT FROM AUTHOR]