POSITIVE ELECTRODE ACTIVE MATERIAL WITH ENHANCED ELECTRODE EFFICIENCY AND ENERGY DENSITY CHARACTERISTICS

摘要

The present invention provides a positive electrode active material having a composition of LiFe(P1-XO4) (where P has a mole ratio of 0.910 to 0.999) of chemical formula (1). The positive electrode active material of the present invention has an operating efficiency leveled to the operating efficiency of a negative electrode active material, which is relatively low, and may improve the energy density of the positive electrode active material. Further, as the positive electrode active material, in which the mole ratio (1-x) of phosphorus (P) is adjusted to less than 1, has Fe2+ and Fe3+ coexisting therein, structural collapse caused by the deficiency of phosphorus (P) is prevented, ion conductivity is improved to achieve superior rate capabilities, and IR drop is suppressed during charging/discharging, thus improving energy density.