Preparation method for cobalt-manganese-nickel oxides

Abstract

The invention discloses a preparation method for cobalt-manganese-nickel oxides. The preparation method comprises steps of separately dissolving industrial products including manganese sulfate monohydrate, cobaltous sulfate heptahydrate and nickel sulfate hexahydrate by hot water, gradually adding a NH4HCO3 solution for performing a neutralization reaction and a precipitation reaction, then continuing to add a KOH solution to react, discharging, filtering, washing by water until SO42-ions disappear, drying, roasting by a high-temperature furnace at the temperature of 820 DEG C for 2-3 hours, ball milling and smashing, stirring and washing by hot water, then filtering, washing, drying and smashing to obtain the cobalt-manganese-nickel oxides. The preparation method is simple, easy to operate, and low in production cost; and the prepared cobalt-manganese-nickel oxides are excellent in product uniformity, stability and electric property, and low in production cost, and can be used for industrial production.

Description

technical field [0001] The invention belongs to the technical field of preparation of electronic functional powder materials, and in particular relates to a preparation method of cobalt, manganese and nickel oxides. Background technique [0002] Electronic semiconductor materials can be obtained by mixing CoO, MnO, and NiO through high-temperature firing. The resistance of this material decreases when the temperature rises, and the temperature coefficient of resistance is large, so it can be used as a negative characteristic thermistor (NTC). (NegativeTemperatureCoefficient, NTC) resistance refers to a material whose resistance value decreases exponentially with increasing temperature within the operating temperature range. NTC thermistors are used in electronic thermometers, temperature control electronic equipment, etc. Lithium-ion batteries are composed of three elements: positive electrode, negative electrode, and electrolyte. Cobalt-manganese-nickel oxide powder materi...

AI Technical Summary

Problems solved by technology

[0003] CoO, MnO, and NiO can be mixed and fired at high temperature to obtain electronic semiconductor (NTC) materials and cobalt-manganese-nickel oxide ternary materials for preparing lithium battery cathode materials. The method for preparing Co-Mn-Ni oxide powder mainly includes solid phase method, liquid phase method and gas phase method, the most common is the solid phase method, in which cobalt, manganese and nickel oxides are mainly prepared by mixing and calcination. This method puts CoO, MnO, NiO and other powders together according to the formula It is made by ball milling in a ball mill for tens of hours, and then granulated, pressed into tablets, sintered and other processes to make electronic components. The ceramic material prepared by the solid phase mixing method has the defects of poor uniformity and insufficient fineness of the ceramic material.

The impact of this on component manufacturing is reflected in the following three aspects, (a) uneven porcelain material leads to poor product consistency and low pass rate

(b) The electrical properties of the product are not good, due to the inhomogeneity of the ceramic material, the crystal grains and crystal phases are inconsistent during the sintering process

(c) Since the fineness of the ceramic material is not fine enough, the sintering temperature is high, which increases the production cost and has an adverse effect on the performance

The liquid-phase synthesis method includes a variety of synthesis methods such as precipitation method, sol-gel method, and hydrothermal method. In the case of uniform chemical solvents, uniform nanometer-sized powders can be obtained, and then more ideal thermistor resistivity and electrical properties can be obtained. Performance, but the operation is more complicated, the experiment requirements are relatively high, and it is difficult to achieve repeated and stable production

The gas phase method can improve the powder mixing degree and refine the particles, but the process is complicated, the equipment requirements are high, and it is not easy to operate

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