▎ 摘　　要

NOVELTY - Binary cathode material comprises lithium-nickel-manganese-oxide based component (LiaNixMnyMzO2), where x is 0.5-0.8, y is 0.05-0.4, z is 0.1-0.2, sum of x, y and z is 1, a is 1.03-1.05, and M is a transition metal element. USE - Binary cathode material for lithium ion battery (claimed). ADVANTAGE - The binary anode material has improved stability, and electrochemical performance of the lithium ion battery comprising binary cathode material is improved. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a method for preparing the binary cathode material, which involves: (a) weighing nickel-containing compound, manganese-containing compound, lithium-containing compound, and pinning agent based on element ratio in binary cathode material, combining nickel-containing compound, manganese-containing compound, and lithium-containing compound, and dispersing pinning agent in first solvent to obtain dispersion, where pinning agent comprises compound containing transition metal element and carbon material; and (b) calcining dispersion liquid in oxygen-containing atmosphere to obtain binary cathode material; and (2) a lithium ion battery, which comprises positive electrode, negative electrode and electrolyte, where positive electrode comprises binary positive electrode material.