The invention discloses a
niobium-doped
single crystal nickel-enriched ternary positive
electrode material and a preparation method thereof. The
niobium-doped
single crystal nickel-enriched ternary positive
electrode material comprises a
nickel-enriched ternary positive
electrode material, the chemical general formula of the nickel-enriched ternary positive
electrode material is LiNi < x > Co < y > Mn < z > O < 2 >, wherein x ranges from 0.79 to 0.81, y ranges from 0.09 to 0.11, and z ranges from 0.09 to 0.11; the nickel-enriched ternary positive
electrode material is of a single-
crystal structure, and Nb < 5 + > ions are doped in
crystal lattices of the nickel-enriched ternary positive
electrode material. According to the single-
crystal nickel-enriched ternary positive electrode material provided by the invention, the crystal boundary is eliminated in the single-
crystal morphology, and particle
cracking and
electrolyte erosion in the circulation process are effectively inhibited; nb5 < + > is doped into crystal lattices, and due to the fact that the
ionic radius of the Nb5 < + > is large, the Nb5 < + > serves as a supporting column, the
lithium interlayer spacing is enlarged, the
lithium ion migration energy barrier is reduced, meanwhile, the
crystal structure is stabilized, and Li < + > / Ni < 2 + > cation mixed arrangement is reduced.