Lithium-rich anode material for lithium ion battery and preparation method thereof

Abstract

The invention provides a lithium-rich anode material for a lithium ion battery and a preparation method thereof. The chemical formula of the anode material is Li[LixCo1-x-y-z-a NiyMnzCea]O2, wherein x is more than 0 and less than 1, y is more than or equal to 0 and less than 1, z is more than or equal to 0 and less than 1 and alpha is more than 0 and less than or equal to 0.3. The preparation process is as follows: firstly, mixing cobalt salt, nickel salt, manganese salt, ceric salt and water at ratio of 1-x-y-z-a:y:z:a, thereby obtaining a first solution; mixing oxalic acid matters, urea and water, thereby obtaining a second solution; under inert gas shielding, mixing the first solution with the second solution and performing coprecipitation reaction, thereby obtaining an oxalate precursor; milling and mixing lithium source with oxalate precursor, roasting the mixed powder, and then obtaining the lithium-rich anode material for the high-capacity lithium ion battery. The lithium-rich anode material provided by the invention is uniform in size distribution, excellent in high-magnification charge and discharge performance, low in initial irreversible volume and high in cycling stability.

Description

technical field [0001] The invention relates to the technical field of lithium battery materials, in particular to a lithium-rich cathode material for a lithium ion battery and a preparation method thereof Background technique [0002] Lithium-ion batteries have the advantages of long cycle life and high energy density, and are widely used in mobile phones, laptop computers and other electronic products, and are considered to be the most reliable energy storage and conversion devices at present. Lithium-ion battery cathode materials account for more than 40% of the total cost of lithium batteries. The performance of cathode materials directly affects the performance indicators of lithium batteries and occupies a core position in lithium batteries. [0003] Lithium-rich cathode material Li 1+x A 1-x o 2 (A=Mn, Ni, Co, etc.) contains a certain amount of lithium in the transition metal layer, and the specific capacity is as high as 300mAh / g. It is an important candidate posi...

AI Technical Summary

Problems solved by technology

[0004] However, in practical applications, lithium-rich cathode materials have the problem of high irreversible capacity loss during the first cycle, and when the charge cut-off voltage is high, it is easy to cause lithium-rich cathode material electrolyte and Li 2 MnO 3 Decomposition, the material structure collapses, resulting in poor cycle stability, which cannot meet the application requirements. These shortcomings still exist in lithium-rich cathode materials, which severely limit its application in high-energy lithium-ion batteries.

Images