NEGATIVE ELECTRODE ACTIVE MATERIAL, AND NEGATIVE ELECTRODE AND SECONDARY BATTERY WHICH INCLUDE THE SAME

A negative electrode active material including artificial graphite particle, wherein a thermal expansion coefficient measured by a specific method is in a range of 108×10/K to 150×10/K. The negative electrode active material has excellent adhesion to an electrode, and has excellent processability and long-term cycle life characteristics accordingly, and the negative electrode including the negative electrode active material has high capacity and excellent initial efficiency.