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Nanostructured manganese sulfide (MnS) has been verified to be effective to address the issues of MnS as next‐generation anode material in high energy lithium‐ion batteries (LIBs). The scale‐up fabrication, however, is still challenged by the multistep and rigid processes of synthesizing MnS nanoparticles. Herein, by using micro‐sized MnS as low‐cost MnS source, we present a facile, cost‐effective and scalable strategy to prepare a sub‐micrometer sized MnS@NSC composite, in which MnS nanoparticles are encapsulated into N,S‐codoped carbon matrix (NSC) deriving from polyacrylonitrile (PAN). The NSC matrix combined with homogeneously distributed MnS nanoparticles crushed from micro‐MnS provide fast access of lithium ion/electron and robust structure, leading to remarkable cycling stability (551.6 mAh g−1 at 0.5 A g−1 even after 400 cycles) and desirable rate capability (624 mAh g−1 at 0.1 A g−1 and around 300 mAh g−1 at 2 A g−1). Particularly, the assembled LIB full cell by coupling the anode with LiFePO4 (LFP) cathode presents an encouragingly cycling retention of 96 % after 100 cycles. This work provides a new possibility for design and industrial implementation of MnS as advanced anode materials for LIBs. [ABSTRACT FROM AUTHOR]

The SiO x/Si composite enhanced by dual-carbon (i.e., multiwall carbon nanotubes and carbon) was fabricated from the micro silicon monoxide (SiO) by the combination of high-energy mechanical milling, spray drying and pyrolysis. The obtained SiO x/Si particles were composed of Si-suboxide and embedded nano-sized Si crystallites. As one of dual-carbons, the multi-walled carbon nanotubes were directly scaffolded of anchoring the SiO x/Si composite particles through spray drying. Another carbon source was directly deposited on the surface of the SiO x/Si by means of the carbonization of phenol-formaldehyde resin. Nano-sized silicon embedded in the Si-suboxide matrix and dual-carbon provided a compromise between the reversible capacity and cycle stability related to the volume change. The obtained SiO x/Si/MWCNT/PC-1 electrode delivered an initial capacity of 936.5mAh g and the reversible capacity was maintained at 825.9mAh g with excellent capacity retention of 87.5% on the 200th cycle versus the 6th one (compared with the same current rate). In contrast, although the SiO x/Si presented the higher initial capacity of 1271.4mAh g, its capacity dropped quickly after several cycles and capacity retention was only 25.6% versus the 6th cycle after 100 cycles. The dual-carbon (MWCNTs and carbon) enhanced SiO x/Si anode materials were fabricated on the basis of the micro SiO, though the combination of high-energy mechanical milling, spray drying and pyrolysis was aiming at low cost and facile up-scaling production. MWCNTs were used as the scaffold of anchoring SiO x/Si. Nano-sized silicon embedded in the Si-suboxide matrix and dual-carbon provided a compromise between the reversible capacity and cycle stability related to the volume change of silicon. [ABSTRACT FROM AUTHOR]

Although some reported porous silicon-based anode materials manifest excellent lithium-ion storage properties, their scalable and economical synthesis remains a large obstacle to their industrial application. This work presents a scalable and efficient preparation of hierarchical porous silicon by using cost-effective porous SiO2 as raw material through a modified magnesiothermic reduction approach, in which a rotatable furnace was employed and the hydrofluoric acid (HF) etching treatment was avoided. Moreover, the reaction has a high conversion yield (>95 %). Subsequently, a carbon layer with a thickness of 7 nm has been conformally wrapped onto the surface of the porous silicon through a chemical vapor deposition (CVD) process. The obtained porous Si@C composite exhibits a high reversible capacity at 0.3 A g−1, and retained ca. 40 % of its capacity even at 8 A g−1. Moreover, it has an excellent capacity retention over 300 cycles. The strategies disclosed in the present work and the novel porous Si@C composite may have great potential for the next generation of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Metallic lithium is the most promising negative electrode for high energy rechargeable batteries due to its extremely high specific capacity and the lowest redox potential. However, the low cycle efficiency and lithium dendrite formation during charge/discharge processes consistently hinder its practical application. Here a new dual-salts electrolyte composed of Li[N(SO 2 F) 2 ] and Li[N(SO 2 CF 3 ) 2 ] has been explored to simultaneously cope with these two problems. Under the unique protection of solid electrolyte interphase (SEI) film formed in this electrolyte solution and the improvement in Li crystal growth pattern, high cycle efficiency of ca. 99% and dendrite-free Li deposit have been achieved. Moreover, the excellent cycling performance and favorable lithium morphology can be retained even at high current density of 10 mA cm −2 . This study will greatly promote the development of Li-metal rechargeable batteries with high power and high energy density. [ABSTRACT FROM AUTHOR]

• Fabrication of sub-micro Si/Sn@SiO x -C composite by a facile milling and annealing process without any by-products. • Nano-SnO 2 was in-situ reduced to metallic Sn via ball-milling with micrometer Si. • The prepared composite delivers excellent rate capability and cyclability. • The superior performance is derived from introduction of sn with high electronic conductivity, dual-buffering of inner SiO x matrix and surface carbon layer. Micrometer silicon (MSi) particles are prospective anode material for high energy-density lithium-ion batteries. Aiming at the scale-up production and the improvement in rate capability, a novel sub-micro Si/Sn@SiO x -C (SSSC) composite via a facile two-step process of milling and annealing is designed and synthesized. With the structural uniqueness including in-situ introduction of metallic tin (Sn) originated from mechano-reduction of nano tin dioxide (nano-SnO 2) with MSi, dual-buffering of inner SiO x matrix and uniform surface carbon layer, SSSC electrodes exhibit impressive rate capability and stable cyclability. The optimum architecture of SSSC-73 (i.e. weight ratio of precursor MSi-to-SnO 2 is 7:3) delivers stable cycling with 1102 mAh g −1 (at 0.5 A g −1) over 100 cycles and exceptional rate performance with a high capacity retention of 95% over 500 cycles at 2 A g −1. Particularly, this facile and cost-effective preparation of SSSC composites has no by-products, making it competitive in practical application. A sub-micro Si/Sn@SiO x -C composite was in-situ mechanochemically synthesized by a combinational milling and annealing method and exhibit excellent high-rate performance. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel nano/micro-structured pSi@C composite with buffer void was successfully synthesized via a simple and scalable process with combination of the calcination, spray drying, carbonization and HF etching. The obtained pSi@C composite with this particular structure exhibits high reversible capacity of ca. 2200 mA h g −1 and excellent cycling stability with 90.3% capacity retention after 300 cycles, which benefits from its void spaces between silicon and carbon layer and highly conductive carbon-layer. The simple and scalable synthesis technique and good electrochemical performance of this nano/micro-structured pSi@C composite make it a promising candidate for large capacity lithium ion battery anode material. [ABSTRACT FROM AUTHOR]