| abstract |
And an electrolyte solution containing an additive, wherein the negative active material comprises a Si-based material, the Si-based material is included in an amount of 1 to 70% by weight based on the total amount of the negative electrode, Wherein the additive is fluoroethylene carbonate and a compound represented by the following formula (1). [Chemical Formula 1] (Wherein R 1 to R 3 are each a substituted or unsubstituted C 2 to C 5 alkylene group). |