<p>Silicon is regarded as one of the most promising post-graphite anode materials for high-energy–density lithium-ion batteries owing to its high theoretical specific capacity. However, the large volume variation during lithiation and delithiation causes structural degradation, rapid capacity fading, and low Coulombic efficiency, which seriously restrict its practical application.A double-layer carbon-coating strategy was developed to prepare a Si@hard carbon@soft carbon composite using photovoltaic silicon cutting waste and asphalt as the silicon and carbon sources, respectively. The hard-carbon inner layer and soft-carbon outer layer were designed to buffer volume expansion, improve structural stability, and facilitate lithium-ion diffusion and electron transport.Evaluation of the electrochemical properties revealed that a composite architecture consisting of silicon coated successively by hard carbon and then soft carbon exhibited notably improved lithium-ion retention behavior. Under a current density of 0.2&#xa0;A g⁻¹, the initial lithiation cycle produced a discharge capacity measuring 2095&#xa0;mAh g⁻¹, accompanied by a first-cycle Coulombic efficiency value of 85.46 percent. Following thirty charge–discharge repetitions, the electrode maintained a reversible specific capacity of 1244&#xa0;mAh g⁻¹, which represents 59.4 percent of its original delivery capability. These results demonstrate that the proposed double-layer carbon-coating strategy effectively improves the cycling stability and electrochemical reversibility of silicon-based anodes.</p> Graphical abstract <p></p>