Abstract: Using rice husk as the silicon source, in the mixed molten salt medium of NaCl/KCl/AlCl₃,thenano-silicon powder was prepared by the low-temperature aluminothermic reduction method. X ray diffraction, field emission scanning electron microscopy andhigh-resolution transmission electron microscopy were used to characterize and analyze the composition, structure and electrochemical performance of the prepared silicon samples. The results show that the obtained sample is pure-phase cubic silicon, composed of nearly spherical agglomerates of 100-300 nm, and the primary particle size is 10-20 nm; The nano silicon is used as a negative electrode material for lithium-ion batteries and exhibits quite well electrochemical performance. When the current density is 0.05A·g^-1, the maximum reversible capacity is 2 960 mAh·g^-1. When the current density is increased to 2 A·g^-1, its reversible capacity can reach 1 930 mAh·g^-1; after 200 cycles of 0.5 A·g^-1 current density, the specific capacity is still as high as 1 769 mAh·g^-1.