Dual-cladding 622-type Ni-Co-Mn ternary positive electrode material and preparation method thereof

Abstract

The invention discloses a dual-cladding 622-type Ni-Co-Mn ternary positive electrode material. The molecular formula of the dual-cladding 622-type Ni-Co-Mn ternary positive electrode material is xMO.yMF.LiNi<0.6>Co<0.2>Mn<0.2>O2, wherein M is Na, Mg or Al, x is more than or equal to 0 but less than or equal to 0.09, and y is more than or equal to 0 but less than or equal to 0.09. The dual-cladding622-type Ni-Co-Mn ternary positive electrode material is implemented according to the following steps of 1) primary coating, in which lithium carbonate, Ni<0.6>Co<0.2>Mn<0.2>(OH)2 and an oxide are sequentially added into a ball-milling tank, and dry ball-milling is performed for 6-18 hours; 2) pre-sintering, in which powder in the step 1) is subjected to thermal processing for 6 hours under a temperature of 700-800 DEG C and then is naturally cooled; 3) washing, in which the powder in the step 2) is cleaned with deionized water and then is cleaned with ethyl alcohol; 4) secondary coating, inwhich the powder in the step 3) is taken out and mixed with a fluoride, and the product is placed in water bath for drying under 90-100 DEG C after ultrasonic treatment for 30 minutes; and 5) secondary sintering, in which the powder in the step 4) is subjected to heat preservation under a temperature of 800-900 DEG C and is naturally cooled to obtain the dual-cladding 622-type Ni-Co-Mn ternary positive electrode material. The method is safe and efficient, and the obtained dual-cladding 622-type Ni-Co-Mn ternary positive electrode material is fine and uniform distribution in particle, has a favorable microstructure and has relatively good electrochemical performance.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery cathode material manufacturing, in particular to a double-coated 622-type nickel-cobalt-manganese ternary cathode material and a preparation method thereof. Background technique [0002] As humans pay more attention to energy and environmental issues, energy storage products with high energy consumption and low efficiency (such as lead-acid batteries, nickel-metal hydride batteries, etc.) will be eliminated. Lithium batteries have been widely used in electronic equipment, electric vehicles and other fields due to their advantages such as high specific energy, small self-discharge, long cycle life, and environmental friendliness. Common lithium batteries are composed of several key materials such as positive electrode material, negative electrode material, separator, electrolyte and battery case, so the selection of positive electrode material is particularly important. The first-gener...

AI Technical Summary

Problems solved by technology

The 523-type nickel-cobalt-manganese cathode material technology is quite mature, and many manufacturers can provide commercial products in large quantities, but the 622-type nickel-cobalt-manganese cathode material is still in the technical reserve stage

However, the reduction of manganese content reduces its safety performance and cycle performance. At present, the main methods of modification reported in the literature include ion doping, surface coating and nanotechnology.

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