abstract |
An embodiment of the present invention relates to a negative electrode active material for a lithium secondary battery, a method for preparing the same, and a lithium secondary battery comprising the same, wherein the negative electrode active material contains a silicon-based composite composed of Si and crystalline SiO 2 , the Si and crystalline SiO 2 having crystal grains. The negative electrode active material according to an embodiment of the present invention comprises a silicon-based composite containing Si and crystalline SiO 2 in a crystal grain state, and the reaction of amorphous SiO 2 with lithium in the electrolyte can be excluded since the SiO 2 is crystalline. As such, the silicone-based composite contains crystalline SiO 2 , and thus, the use of the silicone-based composite as a negative electrode active material can maintain excellent capacity characteristics and improve initial efficiency and lifespan characteristics in a secondary battery. |