Preparation method of spinel type lithium manganate with high crystallinity used in lithium ion battery

Abstract

The invention relates to a preparation method of spinel type lithium manganate with high crystallinity used in the lithium ion battery, comprising the following steps: (1) selecting the raw materials: selecting the battery grade electrolytic manganese oxide with the grain size of 3-25 mum and the battery grade Li-containing compound with the average grain size less than or equal to 8 mum and the impurity content less than or equal to 0.5%; (2) mixing the manganese oxide and the Li-containing compound evenly according to the Mn / Li mole ration of 1:0.56-0.58, ball milling and pressing into block mixture; (3) adding the mixture into the continuous sintering furnace, and heating under 730-810 DEG C with constant temperature for 12-24 h in the oxygen containing atmosphere with the oxygen content larger or equal to 30%; after the sintering reaction, cooling under the normal temperature in the continuous sintering furnace for 10-30 h, examining in grade and obtaining the product of Li1+xMn2O4, wherein 0<x<0.2. The method of the invention has simple process, and the crystallinity and the circulating performance of the product are improved with the enhancement of the oxygen content in the sintering atmosphere.

Description

technical field [0001] The invention relates to a preparation method of spinel lithium manganate, in particular to a preparation method of high-crystal spinel lithium manganate used in lithium ion batteries. Background technique [0002] Due to the advantages of high energy density, long cycle life, less pollution, no memory effect, small size, and light weight, lithium-ion batteries are widely used in small mobile electronic products such as mobile phones, notebook computers, and power tools. The battery with the most development potential in the fields of bicycles and electric vehicles. [0003] Lithium cobalt oxide (LiCoO 2 ), spinel lithium manganese oxide LiMn 2 o 4 , lithium nickel cobalt manganese oxide Li (Ni 1 / 3 co 1 / 3 mn 1 / 3 )O 2 . Due to the scarcity of cobalt resources, high price, and the impact of its toxicity on the environment, coupled with the low thermal stability of lithium cobalt oxide during charge and discharge cycles, the development potential ...

AI Technical Summary

Problems solved by technology

[0004] However, during the long charge-discharge cycle of traditional lithium manganese oxide, especially under high-temperature charge-discharge cycles, the cycle performance of the battery is significantly reduced due to the dissolution of manganese, and the Jahn-Teller structure deformation is prone to occur when the discharge is terminated. These factors Both reduce the high temperature cycle performance, cycle performance and high current working performance of the battery

Although doping, surface coating and other methods can reduce the dissolution of manganese to a certain extent and improve the cycle performance, but due to the addition of inactive substances, the energy density of the battery is often sacrificed, and the preparation process is complicated. The impurity elements are mainly Co, Ni, etc., which will also cause environmental pollution and increase costs

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