NEGATIVE ELECTRODE ACTIVE MATERIAL WITH IMPROVED SAFETY, AND SECONDARY BATTERY COMPRISING SAME

The present invention relates to a negative electrode active material for an electrode composition, and to an electrochemical cell comprising the negative electrode active material, wherein the negative electrode active material comprises an amorphous carbonaceous material and a doping element, and exhibits, in the temperature range of 450°C to 950°C, at least two peaks of weight reduction variation calculated by thermogravimetric analysis, and exhibits a maximum heat peak output of 20 mW to 60 mW as measured by differential scanning calorimetry.