## 2 SiOC-Based Anode Materials
These mechanisms make SiOC/Sn nanocomposites exhibit excellent electrochemical properties as anode materials for lithium-ion batteries, which is expected to solve the volume expansion problem of alloy materials and improve the energy density of batteries. Furthermore, [PERSON] et al. (2018) enhances Si anodes via a dual-matrix design. Covalent seeding embeds Si nanoparticles within a SiOC buffer (Si@SiOC), showing an improved capacity. Adding tin nanocrystals (SiSn@SiOC) creates internal voids to accommodate volume changes and boosts conductivity. The optimized composite delivers 1330 mAh\(\cdot\)g\({}^{-1}\) capacity and exceptional cycling stability (96.5% retention after 200 cycles). The relevant performance is shown in the Figure 6. It validates the dual-matrix design as a holistic solution for Si anodes: Sn simultaneously enhances capacity (alloying), conductivity (metallic pathways), and cyclability (void-mediated stress relief). The optimal SiSn\({}_{1.0}\)@SiOC formulation balances high energy density (1329 mAh\(\cdot\)g\({}^{-1}\)) with unprecedented mechanical-electrochemical durability, setting a benchmark for structurally integrated composites. Figure 6: **(a)** Initial CCD curves and **(b)** cycling stability of Si@SiOC and various SiSn@SiOC electrodes. **(c)** Sheet resistances of bare SiOC, Si@SiOC, and various SiSnx@SiOC electrodes. **(d)** Nyquist plots of Si@SiOC and SiSn@SiOC electrodes after formation cycles and 100 cycles. Cross-sectional SEM images after 100 cycles and thickness change before and after cycling of **(e)** Si@SiOC and **(f)** SiSn@SiOC electrodes (delithiated states) Copied with permission from the Royal Society of Chemistry (2018). [PERSON] et al. [33] employed covalent-assisted seeding technology to establish robust covalent bonds between silicon nanoparticles and the SiOC matrix. They further introduced a dual-matrix design by incorporating tin nanocrystals as pore triggers within the Si@SiC framework, thereby creating internal artificial voids. The resulting SiSn@SiOC composite demonstrated excellent electrochemical performance. Similarly, [PERSON] et al. [37] recently engineered a 3D micron-sized SiOC anode with an in situ Cu\({}_{3}\)Si interphase through solvent-free ball milling (Figure 7). The conductive Cu\({}_{3}\)Si alloy buffered mechanical stress, enhanced interfacial stability, and facilitated an LiF-rich SEI, achieving 78% initial coulombic efficiency and remarkable long-term cycling (750 mAh\(\cdot\)g\({}^{-1}\) after 1000 cycles at 1 A\(\cdot\)g\({}^{-1}\)) in half-cells, alongside 93% capacity retention in NCM811 full cells. [PERSON] et al. [35] developed a three-dimensional (3D) lamellar SiOC@C/rGO composite through a hydrothermal reaction and electrostatic self-assembly process. In this composite, SiOC powders are encapsulated by amorphous carbon layers and uniformly dispersed within reduced graphene oxide (rGO) sheets. The combination of carbon-free nanoclusters in SiOC, carbon layers on its surface, and the rGO support creates a multidimensional interconnected conductive network, improving interfacial adhesion. As a result, the SiOC@C/rGO composite exhibits a high specific capacity (676 mAh\(\cdot\)g\({}^{-1}\) at 200 mA g\({}^{-1}\)) and exceptional rate capability (306.4 mAh\(\cdot\)g\({}^{-1}\) at 4000 mA g\({}^{-1}\)). When integrated into a full cell with a LiFePO\({}_{4}\) cathode, it shows a stable voltage platform and reliable performance over 200 cycles. The superior electrochemical performance of SiOC@C/rGO is attributed to the synergistic effects of its robust structure, multidimensional conductive network, and enhanced chemical stability. [PERSON] et al. [38] use in situ Raman spectroscopy revealed that the vertically grown graphene coating on the Hp-SiOC@VG anode primarily enhances conductivity rather than contributing significantly to Li\({}^{+}\) storage. In addition, by analyzing the changes in the position and intensity of the G-band, the reversibility of the graphene layers during the lithium insertion and extraction processes was revealed.