| abstract |
The present invention, An electrode assembly each including at least one anode, cathode and separator; And lithium secondary battery comprising a lithium non-aqueous electrolyte, The positive electrode, as a positive electrode active material, includes an excess of lithium transition metal oxide represented by Formula 1, The negative electrode, as a negative electrode active material, contains a Si-based compound in an amount of 1% by weight based on the total weight of the negative electrode active material, The lithium non-aqueous electrolyte includes a lithium salt and a non-aqueous organic solvent, The non-aqueous organic solvent provides a lithium secondary battery comprising a fluorine (F) group-containing solvent in an amount of 20% by volume or more based on the total volume of the non-aqueous organic solvent. [Formula 1] Li a (Ni x Mn y Co z A w ) O 2-b X b In Chemical Formula 1, A is one or more elements selected from the group consisting of W, V, Cr, Nb, Mo, Fe, and Al, X is one or more elements selected from the group consisting of P, N, F, S and Cl, 1<a≤1.2, 0≤b≤0.02, 0<x≤0.5, 0.2≤y≤0.8, 0.15≤z≤0.5, 0≤w<0.2, a+x+y+z+w=2. |