The present invention provides a
lithium secondary battery including a positive
electrode, a negative
electrode, a separator, and a non-
aqueous electrolyte, wherein the positive
electrode includes a positive electrode active material, the positive electrode active material includes
lithium iron phosphate particles, the loading amount of the positive electrode is 450 mg / 25 cm 2 to 740 mg / 25 cm 2 , the non-
aqueous electrolyte includes a
lithium salt, an
organic solvent, and an additive, wherein the
organic solvent includes 10 to 35% by volume of
ethylene carbonate, 5 to 55% by volume of
dimethyl carbonate, and 20 to 70% by volume of ethyl
methyl carbonate, and the volume ratio of the cyclic
carbonate-based
solvent to the linear
carbonate-based
solvent is 10:90 to 35:65, the additive includes
vinylene carbonate, and the weight ratio of the
vinylene carbonate to the
dimethyl carbonate is greater than 0 to 0.2 or less. By improving the negative electrode reduction stability while improving the impregnation properties of the positive electrode to the non-
aqueous electrolyte, the lithium secondary battery has excellent capacity performance effects, excellent life performance, and resistance reduction effects.