| 摘要 |
PURPOSE: A lithium secondary battery is provided to have excellent capacity retention rate according to use and to remarkable reduce thickness expansion. CONSTITUTION: A lithium secondary battery (100) is formed of a positive electrode (112) incuding a negative electrode active material, a positive electrode (114) including a positive electrode active material, a polymer, a lithium salt having a borate structure, and an electrolyte including an organic solvent. The electrolyte includes 0.1 to 10wt% of the lithium salt having a borate structure in 100wt% of the electrolyte. The organic solvent comprises an acetate-based compound and a cyclic carbonate-based compound. A content of the acetate-based compound is greater than a content of the cyclic carbonate-based compound. The acetate-based compound is included at a content of 30 to 80vol% in 100vol% of the organic solvent. |
