Nano-Si composite with a <10 nm homogenous porous carbon coating layer was fabricated by a facile approach with phenolic resin as carbon source, Pluronic 123 (P123) as pore forming agent and cetyltrimethyl ammonium bromide (CTAB) as surfactant. The composite electrode exhibited a high lithium storage capacity of 960 mAh g−1 over 100 cycles at 1 A g−1 and could maintain reversible capacities of 810 mAh g−1 at 0.5 A g−1 over 400 cycles. The superior electrochemical performance could be due to the homogeneous and unique porous thin carbon shell for Si.