CYLINDRICAL LITHIUM SECONDARY BATTERY

The present invention relates to a cylindrical lithium secondary battery including an electrode assembly in which a positive electrode, a separator, and a negative electrode are sequentially stacked and wound in one direction, an electrolyte, and a battery case in which the electrode assembly and the electrolyte are accommodated, wherein the electrolyte includes an ester-based solvent, and a diffusion of ions in a battery (DIB) value defined by Equation 1 below is 162 mS/mm2 to 635 mS/mm2. DIBDiffusionofIoninaBattery=hR×1r×C×t+×1000In Equation 1 above, h (unit: mm) is the height of the cylindrical lithium secondary battery, R (unit: mm) is the diameter of the cylindrical lithium secondary battery, r (unit: mm) is the radius of a winding central portion of the electrode assembly, C (unit: mS/mm) is the ion conductivity of the electrolyte, and t+ is the cation transport rate of the electrolyte.