A single-crystalline-structured low-cobalt ternary positive material, a chemical formula thereof is Li1+x(NiaCobMnc)1-dMdO2-yAy, where a mole fraction of Co element is low. 0.05 ≤ b ≤ 0.14; and in a single particle, a ratio of an average Co content per unit area of an outer layer to an average Co content per unit area of an inner core in a cross section passing through a geometric center of the particle is in a range 1.2-5.0:1, optionally, in a range 1.4-2.0:1 is disclosed. The material has better structural stability and dynamic performance at low temperature and high voltage, which improves cycle performance and power performance of the secondary battery at low temperature and high voltage. A method for preparing the low-cobalt ternary positive material, a secondary battery, a battery module, a battery pack, and a power consumption apparatus including the material is also disclosed