ANODE ACTIVE MATERIAL, METHOD FOR PREPARING SAME, ANODE COMPOSITION, ANODE FOR LITHIUM SECONDARY BATTERY COMPRISING SAME, AND LITHIUM SECONDARY BATTERY COMPRISING ANODE

A negative electrode active material includes a silicon-based active material having a crystal grain size of about 300 nm or less. The silicon-based active material has a value of about 2.00 or less as defined by Equation 1 below. The silicon-based active material includes SiOx (x=0) and at least one selected from SiOx (0