To dispose the fragility and poor conductivity problems of SiO‐based anode materials, a “phase change mediation combined with cord reinforcing” concept is proposed, in which graphene cord is in situ fabricated combined with Si and SiO2 nanodomains generated in the SiO matrix via chemical vapor deposition. Being the fabricated composite, graphene cord not only bridges but also wraps the SiO particles, improving the electrical conductivity and flexibility of the fabricated SiO@Gra anode. Moreover, the increased SiO2 regions in the Si/SiO matrix alleviate volume change and release the strain for Li+ insertion, enhancing the tenacity of the SiO electrode according to the phase transformation flexibility mechanism. Besides, the grain boundaries and interfaces among the Si/SiO2/SiO regions contribute to additional Li+ storage and pledge more channels for Li+ transfer and electrolyte wetting. The merit of Si/SiO2/SiO synergistically contributes to the ascendant electrochemical performance of the SiO anodes. The as‐fabricated SiO@Gra anodes deliver a high reversible capacity of 1127 mAh g−1 at 0.2 A g−1 with 87% capacity retention after 200 cycles. The proposed phase change and cord reinforcing not only deepen the understanding of the electrochemical reaction mechanism of Li+ in SiO, but also inspire a rational design tactic for advanced lithium‐ions batteries.

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Silica (SiO2) is considered as a promising candidate anode material for next-generation lithium-ion batteries (LIBs) owing to its low cost, abundant reserve on Earth, and relatively high theoretical specific capacity. However, the development of SiO2-based anode materials has been impeded by their poor electrical conductivity and sluggish charge-transfer kinetics. Herein, porous SiO2/tin (SiO2@Sn) composites with tunable SiO2 to Sn molar ratios are fabricated using a scalable, simple, and low-cost ball-milling and low-temperature thermal-melting combined method. It is found that the Sn phase can significantly improve the diffusion and migration kinetics of Li in the composites, whereas the SiO2 to Sn molar ratio plays a key role in the mechanical integrity and subsequent cycling behaviors of the composite electrodes. By optimizing the molar ratio of SiO2/Sn to 10:1, the synergistic effect of Li storage between SiO2 and Sn can lead to the simultaneous achievement of improved Li kinetics and ensured mechanical integrity, contributing to the excellent electrochemical performance of the composite with a large reversible capacity of 613 mAh g–1 at 100 mA g–1, a remarkable rate capability of 450 mAh g–1 retained at 1000 mA g–1, and long-term cycling durability with ∼95% capacity retention over 200 cycles.

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Antimony (Sb) is regarded as a promising anode material for sodium ion batteries (SIBs) on account of its high theoretical specific capacity (∼660 mAh g–1) and low cost. However, the large volume expansion (∼390%) during charging has inhibited its practical application. Herein, hexagonal Sb nanocrystals encapsulated by P/N-co-doped carbon nanofibers (Sb@P-N/C) were prepared using a low-cost but mass-produced electrospinning method. The as-prepared Sb@P-N/C, used as anode material for SIBs, exhibits unexpected cycling stability and rate capability, with 500.1 mAh g–1 at 50 mA g–1 after 200 cycles and 295.6 mAh g–1 at 500 mA g–1 after 400 cycles. Especially, the full battery fabricated by Na (Ni1/3Fe1/3Mn1/3) O2 || Sb@P-N/C possesses a reversible specific capacity of 66.8 mAh g–1 at 50 mA g–1 over 60 cycles. This simple and low-cost fabrication technology combined with unique crystal morphology offers new strategies for the advancement of sodium ion batteries (SIBs) in energy storage and electrical transportation.