Process for preparing lithium cobalt oxide of lithium-ion secondary battery cathode materials

Abstract

The invention provides a process for preparing lithium cobalt oxide of lithium-ion secondary battery cathode materials. The process includes that cobalt oxide or hydroxyl cobalt oxide powders and lithium carbonate powders are mixed according to a lithium / cobalt molar ratio of 1.0-1.1 and calcined in an atmosphere containing oxygen at the temperature of 850-1100 DEG C; obtained mixture is calcined for 5-55 hours in the atmosphere containing oxygen at the temperature of 850-1100 DEG C; calcined products are naturally cooled to reach room temperature and then grinded; laser scattered grain size distribution measuring device is used for classifying; lithium cobalt oxide semi-finished products are obtained by selecting an average grain diameter D50 of 8-20 micrometers; and a device with high-speed shear strength function is used for conducting coating composition treatment process on the surfaces of the lithium cobalt oxide semi-finished products. The process has the advantages of low raw material cost, high volume energy density, good safety, fine charge-discharge cycle performance, high pressurizing density and superior productivity.

Description

technical field [0001] The present invention relates to a lithium cobaltate material with excellent characteristics in many aspects such as high volume energy density, safety, charge-discharge cycle, pressurized density and productivity, etc., by using cheap cobalt hydroxide or cobalt oxyhydroxide and lithium carbonate The method, especially a kind of preparation method of lithium cobaltate lithium ion secondary battery anode material. Background technique [0002] In recent years, with the development of portable and wireless equipment, the demand for non-aqueous electrolyte secondary batteries such as lithium-ion secondary batteries with small size, light weight and high energy density has been increasing. As we all know, the positive electrode active material for this non-aqueous electrolyte secondary battery has LiCoO 2 , LiNiO 2 、LiNi 0.8 co 0.2 o 2 、LiNi 0.33 co 0.33 mn 0.33 o 2 , LiMn 2 o 4 、LiFePO 4 Composite oxides or phosphates of lithium and transition...

AI Technical Summary

Problems solved by technology

[0007] However, in lithium cobalt oxide to which foreign elements are added, since the foreign elements do not contribute to the battery reaction (charge-discharge reaction), there arises a problem that the capacity of the battery decreases and the charge-discharge efficiency also decreases as the amount of these foreign elements added increases.

In addition, since the crystallinity is lowered due to the addition of different elements, there are also problems that the thermal stability is lowered and the load performance is also lowered.

Moreover, there is still much room for improvement in charge and discharge efficiency performance.

[0008] Therefore, those of ordinary skill in the art have not foreseen the use of low-cost raw material cobalt hydroxide, which can produce a desired particle size distribution, and can form a high volume energy density, safety, charge-discharge cycle, pressurized Lithium cobalt oxide with excellent characteristics in many aspects such as density and productivity

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