NEGATIVE ELECTRODE ACTIVE MATERIAL, PROCESS FOR PREPARING THE SAME, AND SECONDARY BATTERY, BATTERY MODULE, BATTERY PACK AND APPARATUS RELATED TO THE SAME

The present application provides a negative electrode active material, a process for preparing the same, and a secondary battery, a battery module, a battery pack and an apparatus related the same. The negative electrode active material comprises a core material and a polymer-modified coating layer on at least a part of a surface of the core material, the core material is one or more of a silicon-based negative electrode material and a tin-based negative electrode material, the polymer-modified coating layer comprises sulfur element and carbon element, the sulfur element has a mass percentage of from 0.2% to 4% in the negative electrode active material, the carbon element has a mass percentage of from 0.5% to 4% in the negative electrode active material, and the polymer-modified coating layer comprises a —S—C— bond.