The urgent demand for lithium ion batteries with high energy density is driving the increasing research interest in Si, which possesses an ultrahigh theoretical capacity. Though various modification strategies have been proposed from the aspects of electrolytes, binders, Si‐M alloys, and Si/C composites, the preparation of nano‐structured Si is the first step for industrial application, since it has the potential solve the intrinsic problem of severe volume change during the lithiation/delithiation process. A series of Si nanostructures including 0D (nanoparticles), 1D (nanowires, nanotubes), 2D (thin film), and 3D (porous structure) have been developed and displayed encouraging results. However, it remains a great challenge to realize industrial production with acceptable cost and batch stability. In this review, the preparation development of nano‐structured Si is revisited. After briefly introducing the market situation for nanostructured Si, the fabrication of various kinds of nanostructure Si are introduced, and the corresponding progress including ball milling, magnesium thermal reduction, temple method, chemical vapor deposition, and chemical etching are comprehensively reexamined and compared from the perspective of mechanism, cost, technical maturity, and recent development. Finally, the further directions of nano‐structured Si preparation toward industrial production are deeply discussed. This review of preparation of nanostructured Si helps to pave the way toward commercial application of high energy density Si‐anodes.

Si-based anodes have the advantages of high energy density and abundant reserve. However, their severe volume change during the charge–discharge process leads to particles’ pulverization and electrode destruction, which hinder their commercial application. Nanostructured Si is effective at relieving the expansion strain, and binders with a small proportion have been proven to play a pivotal role in maintaining the Si-based electrode integration. Si nanoparticles of various sizes show different particuological behaviors, including distribution, aggregation, etc. Moreover, the binders with specific molecular structure also have unique bonding characteristics with Si particles of different sizes. Except the aforementioned aspects, the process techniques of Si nanoparticles and binders also greatly affect the electrode. Though some pioneering reviews about the progress of binders for Si-based anodes have been published, in order to boost the practical application of Si-based anodes, it is urgent to revisit the previous investigations to clarify the correlation of the particle size, binder structure, and process techniques.

The particle size of Si raw materials is closely related with the stability and the cost of the final Si-based anode. Nevertheless, the detailed mechanism is still unclear. In the present study, Si particles with different sizes (100 and 500 nm and 1 μm) were used to prepare a nanoporous Si@C (P−Si−C) anode via Si−Mg alloy intermediate and carbon coating with Mg reduction of CO 2 . Contrary to the general idea, we found that P−Si−C synthesized with larger particle size of silicon exhibited better performance, and P−Si−C (1 μm) could maintain a specific capacity of 1741.1 mAh/g after 70 cycles at a current density of 0.5 A/g, with a capacity retention rate of 81.2%. It enlightens us that silicon−carbon composites can be prepared with low-cost largegrained silicon, which has significant guidance for industrial applications.

The size of silicon (Si) particles and used binder directly affects the flow uniformity of the slurry, the mechanical properties, and the electrochemical performance of the electrode. In this study, we tried to clarify the adaptation law of Guar gum (GG) and sodium alginate (SA) with 200 nm-Si and 1 μm-Si from the above-mentioned aspects. The rheological properties of the slurry showed that the slurry with GG due to the gelatinization had a poorer dispersion than that with SA. The tests of zeta potentials, thermogravimetric analysis, peeling-off, and nano-indentation profiles explained the performance differences of the electrodes from the mechanical properties. Because of more hydrogen bond sites, the discharge specific capacity of the nm-Si/GG electrode (1116.05 mA h g−1) was higher than the nm-Si/SA electrode (657.74 mA h g−1) after 70 cycles. On the contrary, the μm-Si/SA electrode owing to a rigid skeleton in the SA molecule exhibited a discharge specific capacity of 1681.47 mA h g−1 after 50 cycles, while the μm-Si/GG electrode was 486.58 mA h g−1. In addition, the results inspire more reasonable optimization of the Si-based electrode design.

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