| 摘要 |
The present invention relates to a lithium secondary battery, regarding a lithium secondary battery comprising a cathode, an anode, a separator arranged between the cathode and the anode, and a non-aqueous electrolyte solution, which comprises: the cathode comprising a cathode active material represented as the chemical formula 1; and the separator comprising a porous polymer substrate with the average pore size of 24-35 μm, 45-55% of porosity, and thickness of 10-20 μm. According to the present invention, sudden decline in durability of a lithium secondary battery can be prevented by applying a separator and using a cathode comprising a high capacity metal oxide represented as the chemical formula 1 at the same time. The chemical formula 1 is Li[Li_xM_(y-y′)M′_y′]O_(2-z)A_z, and 0<x<0.5, 0.6<y<1.1, 0<=y′<0.2, 0<=z<0.2 in the chemical formula 1, wherein M′ is at least one species selected from the group consisting of Al, Mg, and B, and A is at least one species selected from the group consisting of F, S, and N. |
