NEGATIVE ACTIVE MATERIAL FOR SECONDARY BATTERY, AND ELECTRODE AND SECONDARY BATTERY INCLUDING THE SAME

摘要

A negative active material for a secondary battery according to the present invention includes a core carbon material and a carbide layer formed on at least a portion of an edge of the core carbon material, and has a difference (an amount of compression density change) of 0.5g/cc or more between a first compression density measured when a pressure of 63.704 MPa is applied for 2 seconds and a second compression density measured when a pressure of 6.3704 MPa is applied for 2 seconds. A secondary battery manufactured using the negative active material according to the present invention can prevent deterioration of characteristics caused by destruction of the carbide layer during a compression process in the manufacture of an electrode of a secondary battery. As a result, a cycle efficiency and a discharging capacity retention rate at a long cycle can be improved.