Method for preparing nickel lithium manganate having spinel structure by static mixer type reactor

Abstract

The invention discloses a method for preparing nickel lithium manganate (LiN0.5Mn1.5O4) having a spinel structure by a static mixer type reactor, which comprises the following steps: a mixing solution of a nickel source and a manganese source as well as a carbonate solution is placed according to equal volume flow from one end of the static mixer type reactor, a liquid phase mixing reaction is carried out in the static mixer type reactor to generate an emulsion, the emulsion is aged and a membrane is washed to remove the impurity ion, and a nickel manganese composite carbonate precursor powder is obtained through spray drying, the precursor powder is coasted at the temperature of 400-500 DEG C for 5-10 hours to obtain a nickel manganese composite oxide, the lithium source is added in the nickel manganese composite oxide according to mol ratio of Li<+> to Ni<2+> to Mn<4+> being 1.05: 0.5: 1.5, and performing ball milling and uniformly mixing, and sintering at the temperature of 800-950 DEG C for 8-15 hours to obtain the finished product. The obtained material has the advantages of pure phase, good crystallization, small particle size, narrow particle size distribution and low raw material price, the technology is simple and a continuous industrial production is easy to be carried out, 0.2C initial discharge specific capacity can reach 130mAh / g, and 0.5C multiplying power 50 times circulation capacity maintenance rate is more than 98%.

Description

technical field [0001] The invention relates to a method for preparing a positive electrode material of a lithium ion battery, in particular to a method for preparing a lithium nickel manganese oxide material by using a static mixing tube reactor, and belongs to the technical field of battery material preparation. Background technique [0002] As the cathode material of lithium-ion batteries, spinel lithium manganate has many advantages such as low toxicity, low cost, wide source of raw materials, and good application prospects. But pure LiMn 2 o 4 The electrochemical performance is not ideal, the first charge and discharge capacity is low, the high temperature is not resistant, and the capacity decays quickly. Among them, nickel doped spinel LiNi 0.5 mn 1.5 o 4 Exhibits excellent electrochemical performance, relatively pure LiMn 2 o 4 In terms of spinel LiNi 0.5 mn 1.5 o 4 It has the advantages of high potential platform (4.7V), high specific power, stable crystal...

AI Technical Summary

Problems solved by technology

For example, solid-phase synthesis is a commonly used method. The advantage of this method is that the process is simple and easy to realize industrialization. However, because the reactants are not easy to mix uniformly, the particle size of the product is large and unevenly distributed, and the shape is irregular, so there is insufficient batch stability. question

The sol-gel method has good chemical uniformity of the precursor solution (up to the molecular level), low gel heat treatment temperature, small particle size and narrow distribution, good sintering performance of the powder, and easy control of the reaction process, but the drying shrinkage is large, Industrialization is difficult and the production cycle is long

Ultrasonic spray pyrolysis can obtain materials with better electrical properties, but requires a reaction chamber with a high temperature above 500°C, high equipment requirements, and difficult industrial production

The traditional liquid-phase co-precipitation method usually adopts a batch reactor to operate as a batch method. Due to the limitation of the amount of reaction materials, the reaction process is long-lasting, which is not conducive to large-scale production. With the progress of the reaction process, the reaction conditions (such as concentration , pH value) are constantly changing, which affects the particle size and distribution of the micropowder

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