METHOD FOR PREPARING NEGATIVE ELECTRODE ACTIVE MATERIAL, NEGATIVE ELECTRODE, AND SECONDARY BATTERY

The present invention relates to a method for preparing a negative electrode active material, which includes mixing green coke particles, calcined coke particles, and a binder, and graphitizing the mixture through heat treatment to form an artificial graphite particle in the form of a secondary particle in which primary artificial graphite particles are bonded to each other, wherein an average particle diameter (D50) of the green coke particles is greater than an average particle diameter (D50) of the calcined coke particles.