Lithium ion battery cathode material precursor, lithium ion battery cathode material, preparations methods of lithium ion battery cathode material precursor and lithium ion battery cathode material, and lithium ion battery

Abstract

The invention relates to the field of lithium ion batteries, and discloses a lithium ion battery cathode material precursor, a lithium ion battery cathode material, preparations methods of the lithiumion battery cathode material precursor and the lithium ion battery cathode material, and a lithium ion battery. The structural formula of the precursor is z[(Ni<x1>Co<y1>Mn<1-x1-y1-eta1>D<eta1>)(OH)2].(1-z)[(Ni<x2>Co<y2>Mn<1-x2-y2-eta2>G<eta2>)(OH)2], wherein x1 is greater than or equal to 0.6 and less than 1, x2 is greater than or equal to 0.6 and less than 1, y1 is greater than 0 and less thanor equal to 0.4, y2 is greater than 0 and less than or equal to 0.4, eta1 is greater than 0 and less than or equal to 0.1, eta2 is greater than 0 and less than or equal to 0.1, and z is greater than 0and less than 1. By controlling the gradient change of the doping element D and G at the inner core part and the outer core part of the precursor, a material with a stable crystal phase structure isobtained, and the cycle life of the lithium ion battery cathode material can be effectively prolonged and the stability of the lithium ion battery cathode material can be effectively improved on the basis of maintaining the high capacity characteristic and rate performance.

Description

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a lithium ion battery cathode material precursor and a preparation method thereof, a lithium ion battery cathode material and a preparation method thereof, and a lithium ion battery. Background technique

[0002] At present, electric vehicles are developing rapidly, and the country has shifted from vigorously supporting and restricting this development direction to leaving it to market competition. As a key component of electric vehicles, batteries are facing huge challenges. Cathode materials that restrict the performance and safety of batteries in all aspects need to be studied intensively. Commercial lithium-ion battery cathode material LiNi x co y mn 1-x-y o 2 The reversible capacity of the material increases with the increase of Ni element content in the material, and then the safety performance decreases. That is, when the Ni content is increased to x=0.80, the rev...

Images