• A new top-down strategy for preparing microsize porous silicon is proposed, combined with a nitrogen-doped carbon coating from polyacrylonitrile (PAN).
• Treatment at 400 °C yields a high nitrogen content of 11.35 at% in the PAN coating, enhancing ionic-electronic transport properties.
• The optimized composite anode exhibits remarkable cycling stability, retaining a specific capacity of 857.6 mAh g−1 after 200 cycles at 4 A g−1.
• The porous structure and carbon coating effectively mitigate volume expansion and structural degradation, demonstrating potential for high-capacity energy storage.