Patent ID: 8895187
Filing Date: 2014-11-25
Classification: H01M,Y02E

Abstract:
1. A cathode active material for a lithium secondary battery, comprising a mixture of a lithium/manganese spinel oxide represented by Formula I and a lithium/nickel/cobalt/manganese composite oxide represented by Formula II, wherein the cathode active material exhibits the life characteristics that the capacity at 300 cycles is more than 80% relative to the initial capacity, in the provision that the below conditions (i) and (ii) are satisfied, (i) the lithium/manganese spinel oxide of Formula I has an average particle diameter of 15-30 μm, or the lithium/manganese spinel oxide of Formula I and the lithium/nickel/cobalt/manganese composite oxide of Formula II have an average particle diameter of 15-30 μm, respectively; and (ii) the mixing ratio of the lithium/manganese spinel oxide:lithium/nickel/cobalt/manganese composite oxide is in the range of 10:90 to 70:30 (w/w), wherein, 0≦x≦0.2; 0≦y≦0.1; 0.2≦b≦0.7; 0.2≦c≦0.7; and b+c<1; wherein each oxide is an aggregate of large numbers of oxide units, and wherein an oxide unit of the lithium/manganese spinel oxide of Formula I has a particle diameter of 0.2 to 12 μm and surface area of 0.1 to 1.0 m