Dataset of "A Comparative Study of Physical blending and hydrogel-derived approaches for Si-based anode materials in Li-ion batteries"

Silicon nanomaterials are promising anode materials for lithium-ion batteries (LIB) due to their high theoretical capacity. However, their practical application is hindered by poor electrical conductivity and large volume expansion during cycling. Among these nanomaterials, silicon nanocrystals (SiNC) offer tunable particle size and surface properties that strongly influence electrochemical performance. This study investigates how anode fabrication method and SiNC structural characteristics, including particle size and surface oxidation, affect LIB behavior. Two widely used preparation strategies were compared: (i) physical blending of SiNC with a polyacrylic acid binder and Super P conductive carbon, and (ii) hydrogel-assisted synthesis via in situ polymerization of polypyrrole (PPy) in the presence of phytic acid and SiNC, forming a three-dimensional, flexible, and conductive network. Microstructural analysis, galvanostatic cycling, cyclic voltammetry, electrochemical impedance spectroscopy, and post-mortem characterization revealed complementary strengths and limitations of each preparation method. Smaller SiNC improved capacity retention in both systems, with a more pronounced effect in hydrogel-derived anodes (44% retention after 500 cycles) due to enhanced dispersion and mechanical support. Super P/SiNC anodes exhibited higher initial discharge capacity (2581 mAh/g) and faster lithiation kinetics, whereas PPy/SiNC anodes demonstrated superior long-term cycling stability by mitigating anode degradation. These results highlight the critical interplay between nanomaterial design and electrode architecture and provide mechanistic insight and guidance for the development of next-generation high-performance Si-based anodes.