Preparation method of lithium ion battery anode material lithium manganate and automobile lithium ion battery

Abstract

The invention relates to a preparation technology of a battery anode material and a related automobile battery and particularly discloses a preparation method of lithium ion battery anode material lithium manganate. The method comprises the following steps: using lithium source, Mn3O4 and nanoscale doping metal additive as raw materials for proportioning, then presintering Mn3O4 or the Mn3O4 processed by ball milling, mixing the presintered Mn3O4 with the mixture of lithium source and metal additive; performing the first sintering and second sintering to the mixed raw material; and finally classifying and screening the sintering product to obtain the spinel lithium manganate product with the required grain size. The invention also discloses an automobile lithium ion battery which is assembled by using the spinel lithium manganate prepared by the method of the invention as anode and using graphite as cathode. The preparation method of the invention has simple operation and environmental friend; and the prepared lithium manganate product has excellent product performance.

Description

technical field [0001] The invention relates to a preparation process of a battery cathode material and a related vehicle battery, in particular to a preparation process of a lithium ion battery cathode material and a vehicle lithium ion battery. Background technique [0002] As an energy-saving and environmentally friendly new energy lithium battery cathode material, lithium manganese oxide has good thermal stability, excellent overcharge resistance, high current charge and discharge performance, and good safety assurance; and my country has abundant manganese resources and low raw material costs. The production of lithium manganate has a greater price advantage. Today's civilian or military mobile communication equipment, UPS power supplies, portable electrical appliances such as miner's lamps, and portable electric tools have been widely used in small lithium-ion secondary batteries, and lithium manganate materials have also begun to be gradually applied to such small seco...

AI Technical Summary

Problems solved by technology

[0003] However, at present, lithium manganese oxide still has many shortcomings such as low capacity, large cycle attenuation, and poor high temperature performance.

The dissolution of Mn in the electrolyte and the Jahn-Teller effect are the main reasons for its cycle attenuation

Although many researchers have done a lot of work, manganese dioxide is often used as a raw material. Due to the inherent small primary particle characteristics of manganese dioxide, the prepared lithium manganate has a small primary particle (mostly below 1 μm), Defects such as poor particle uniformity make the contact area between lithium manganate and electrolyte too large. During long-term cycles, especially high-temperature cycles, Mn dissolves in the electrolyte and causes lattice defects.

At the same time, the Jahn-Teller effect inherent in ordinary lithium manganese oxide greatly reduces the high temperature performance and cycle performance of the battery, limiting its application and development in the field of power batteries

[0004] Even though part of the lithium manganate is modified by doping to increase its cycle performance, due to its different purposes and uses, it does not process the raw materials, nor does it refine the sintering system too much. Most of the products have certain crystal defects, which will rapidly attenuate during high-temperature cycling and high-rate discharge conditions. They can only be used as ordinary lithium manganate cathode materials, and it is difficult to professionally promote them as lithium manganate materials for electric vehicles.

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