A high-voltage nickel-cobalt lithium manganese oxide precursor and its preparation method and high-voltage nickel-cobalt lithium manganese oxide positive electrode material

Abstract

The invention discloses a high-voltage nickel-cobalt-lithium-manganese-oxide precursor. The primary particles of the nickel-cobalt-lithium-manganate precursor have a clustered "petal" structure, and the "petals" are flake-shaped; the secondary particles are loose inside. spherical structure. The invention also discloses a method for preparing a high-voltage nickel-cobalt lithium manganese oxide precursor. The preparation method combines the process advantages of high and low pH phase separation through a unique reaction atmosphere design, and the proper matching of output power and flow rate to prepare a The primary particle is "petal-shaped", flake-shaped, and the secondary particle is spherical, porous nickel-cobalt-lithium manganese oxide precursor; compared with the conventional precursor, the primary particle structure is unique, and the secondary particle is loose and porous inside , which provides an important guiding significance for the morphology research of the small particle size nickel cobalt lithium manganese oxide precursor and the optimization of the preparation process. The nickel cobalt lithium manganese oxide precursor is made into a high voltage nickel cobalt lithium manganese oxide positive electrode material, and the high voltage nickel cobalt lithium manganese oxide positive electrode material has a single crystal structure.

Description

technical field [0001] The invention belongs to the field of lithium-ion battery materials, and in particular relates to a high-voltage nickel-cobalt lithium manganate precursor with a special shape, a preparation method thereof, and a high-voltage nickel-cobalt lithium manganate positive electrode material. Background technique [0002] Lithium-ion batteries are widely used as a new type of green battery by the battery industry due to their advantages of no memory effect, high specific energy, and long cycle life, such as digital fields, electric vehicles, and energy storage fields. Lithium-ion batteries are widely used. The excellent performance of lithium-ion batteries depends on the manufacture of advanced battery materials, and the performance of batteries depends largely on the performance of cathode materials. Common cathode materials include lithium cobalt oxide, lithium manganese oxide, and lithium iron phosphate. Due to the characteristics of high discharge capaci...

AI Technical Summary

Problems solved by technology

For example, the patent application with the publication number CN103746111A mentioned the preparation method of the positive electrode material of the single crystal nickel cobalt manganese battery, although the preparation method of the precursor of the positive electrode material of the single crystal battery was mentioned in the application, but this method is not suitable for industrialization; The patent application with the publication number CN103840151A provides a preparation method of a ternary material with a special single crystal structure. It mentions using nickel sulfate, cobalt sulfate, and manganese sulfate as the salt solution, using ammonia water to control the pH value, and putting the reaction kettle into the muffle In the furnace, and then heated at high temperature, although the method is unique, there are risks in the preparation technology in this application. It is proposed to put the reaction kettle into the muffle furnace for heating, which has a huge safety hazard and is not feasible in industrial technology; the publication number is The CN104979546A application provides the primary particle composition, particle size, and BET range of a single crystal precursor, but the BET in this patent is greater than 100m 2 / g, while lithium carbonate BET is at 10m 2 / g or so, the BET has a large difference. During the mixing process, lithium carbonate is easy to mix unevenly, and after mixing, the shape is easy to be fluffy. Higher, and the patent stipulates that the valence states of nickel, cobalt, and manganese elements are both positive divalent, which limits the role of the diversity of valence states of manganese elements

The patent application with the publication number CN104201367A provides a convenient preparation method of a small particle precursor and the analysis of the properties of the precursor, but the patent uses a tight filter tube to control the solid content in the reactor, and the flow rate and stirring power are constant. If the solid content of the reaction system is increased, the agglomeration phenomenon between the secondary particles will be serious, and the crystal form of the primary particles will be easily damaged, and uniform primary particles cannot be obtained, let alone a sheet-like morphology. The test summary shows that using the inventive method mentioned in the patent to prepare the precursor, due to the high solid content of the system, the interior of the obtained precursor is relatively compact, and the primary particles are mostly plate-shaped, which is similar to the SEM image in the patent. The primary particle precursor with thin sheet morphology has a great relationship with the oxygen concentration in the reaction atmosphere, and also has a great relationship with the stirring power and flow rate. Therefore, it is important to deepen the research on the properties and preparation process of single crystal ternary precursors. practical significance

Images