LITHIUM SECONDARY BATTERY

Disclosed (or Provided) is a lithium secondary battery including a positive electrode, a separator and a negative electrode, in which the positive electrode includes a lithium composite transition metal compound including nickel (Ni) and cobalt (Co), the negative electrode includes a silicon-based active material and a carbon-based active material, the efficiency constants of the silicon-based active material and the carbon-based active material and the efficiency constant of the lithium composite transition metal compound satisfy a specific Equation.