Doped cobaltosic oxide and preparation method thereof

Abstract

The invention discloses doped cobaltosic oxide; the morphology of the doped cobaltosic oxide is single-crystal particles or single-crystal-like aggregates, the primary grain size is 200-500 nm, and the half-peak width of the 311 crystal face is 0.2-0.6. The preparation method comprises the steps: adjusting the pH value of a reaction kettle base solution to 7.1+ / -0.05; adding a mixed salt solution containing cobalt and doped elements and an ammonium bicarbonate solution into a reaction kettle for reaction, and controlling the pH value of a reaction system to be 7.1+ / -0.05; standing and clarifying the slurry overflowing from the full liquid level of the reaction kettle, removing the supernatant, controlling the solid content of the slurry, returning the slurry to the reaction kettle for reaction, and stopping feeding until the reaction reaches the target particle size; and washing, drying, sieving and calcining the obtained material to obtain the doped cobaltosic oxide. The doped cobaltosic oxide has a monocrystal or monocrystal-like aggregate morphology, the compaction density is obviously higher, and a guarantee is provided for synthesis of a lithium cobalt oxide positive electrode material with high energy density.

Description

technical field [0001] The invention belongs to the field of lithium ion battery materials, and in particular relates to a doped tricobalt tetroxide and a preparation method thereof. Background technique [0002] With the iterative upgrade of products in the digital field and the rapid development of various high-end aircraft models, drones and other emerging electronic products, the requirements for the lightweight and battery capacity of lithium batteries are getting higher and higher. Lithium cobaltate cathode material has an important application direction in the digital field. As electronic products have increasingly stringent requirements on the performance of lithium batteries, the update and iteration of lithium cobaltate cathode material is particularly important. The performance of the lithium cobalt oxide cathode material largely depends on the performance of the precursor. Currently, in order to prepare a high energy density cathode material, on the one hand, the...

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Problems solved by technology

At present, the preparation technology of single crystal tricobalt tetroxide is generally prepared by spray pyrolysis method. The spray pyrolysis method mainly obtains single crystal tricobalt tetroxide by pyrolysis of cobalt chloride solution, but this method will cause a large amount of hydrogen chloride gas to be produced, and the tail gas treatment is stricter, and The spray pyrolysis method cannot be applied to the preparation of doped single crystal cobalt tetroxide

[0004] At present, lithium cobaltate cathode materials are mostly made of polycrystalline small particles of cobalt tetroxide with conventional secondary spherical particles, but there are relatively high pores inside the polycrystalline small particle raw materials, and due to the small particle size, cobalt and doping elements are in the sintering process. It is easy to form a state of phase separation, which makes the distribution of doping elements uneven, and the positive electrode material prepared by using polycrystalline aggregates has low compaction density and serious battery gas production.

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