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Currently, with the rise of the photovoltaic industry, how to effectively treat waste silicon powder from an environmentally friendly and economic point of view becomes significant. We reported a simple method to prepare the "core-shell" structure of silicon/carbon nanotubes/carbon (Si/CNTs/C) composite by ball-milling using waste silicon powder. Specifically, The synergistic effect of CNTs and amorphous carbon matrix is beneficial to improving the transmission rate of Li-ions and electrons, and facilitating the reaction kinetics of Li-ions in the process of lithiation/de-lithiation. Meanwhile, the carbon coating layer reduces the direct contact between silicon and the electrolyte, which greatly alleviates the volume expansion of silicon in cycling. With these merits, Si/CNTs/C anode shows high rate performance and outstanding cycling stability up to 300 cycles at 0.2C. Furthermore, full cells assembled with pre-lithiated Si/CNTs/C anodes and commercial NCM811 cathodes deliver considerable initial coulombic efficiency (84.4%) and high energy density (502 Wh kg−1). Si/CNTs/C composites prepared by ball-milling show excellent long-cycle stability and rate performance. [Display omitted] • Industrial waste silicon is used to prepare silicon-based anodes. • Two-step ball milling method to prepare Si/CNTs/C composite. • A solution-based chemical prelithiation method is proposed. • Si/CNTs/C anode exhibits excellent long-cycle stability and good rate performance. • A full cell shows an improved ICE (84.4%) and a higher energy density (502 Wh kg−1). [ABSTRACT FROM AUTHOR]

• An N-doped CNT-interspersed hierarchical carbon shell structure by Co-Zn bimetallic ZIFs-triggered surface polymerization of dopamine has been designed and successfully prepared for stabilized silicon anode (PDA@CoZn-NC@Si). • PDA@CoZn-NC@Si electrodes deliver better cycle stability of 814 mAh/g at 0.5C with a capacity loss of −0.14% per cycle over 400 cycles and possess excellent rate capability. • The solution-based chemical prelithiation method is used to compensate for irreversible loss of anode capacity, and the full cell exhibits an improved ICE (88.3%) and a higher energy density (419.8 Wh kg−1). The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni 1/3 Co 1/3 Mn 1/3)O 2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes. [ABSTRACT FROM AUTHOR]

• A three-dimensional Ni,Co-embedded CNT-coated N-doped hollow porous carbon (Ni/Co-CNT/NHPC) cathode has been designed and prepared for lithium-sulfur battery. • The Ni/Co-CNT/NHPC-S cathode possesses a high specific capacity of 1352 mA h g-1 and an excellent cycle stability at 1 C with low capacity decay of 0.094% per cycle over 500 cycles. • The mechanism of suppressing the shuttle effect on the cathode materials is discussed by analyzing adsorption experiments and density functional theory（DFT）calculation. Lithium-sulfur (Li-S) batteries have attracted great attentions due to their high specific capacity. However, the poor cycle stability caused by polysulfide shuttles, volume expansion and formation of lithium dendrites limit their practical applications. In the present work, to tackle the poor stability and unstable rate capability, a MOF-doping strategy is developed to construct a hollow porous carbon framework，which consists of Ni, Co particles and CNT on a N-doped shell surface (Ni/Co-CNT/NHPC). This hollow framework increases the load of S, slows down the volume changes, and can physically entrap soluble polysulfide. It is found that the CNT-coated network structure is beneficial for optimizing the conductivity and wettability of the material, which accelerates the reaction kinetics. Moreover, synergistic effect of abundant defects and Ni, Co nanoparticles strengthens the chemisorption of polysulfides, which suppresses the shuttle effect. As a consequence, the Ni/Co-CNT/NHPC-S cathode harvests a high specific capacity (1352 mA h g-1), and shows an excellent cycling stability at 1 C with low capacity decay of 0.094% over 500 cycles. [ABSTRACT FROM AUTHOR]