Chromium-doped high-voltage high-nickel ternary lithium battery positive electrode material and preparation method thereof

Abstract

The invention provides a chromium-doped high-voltage high-nickel ternary lithium battery positive electrode material and a preparation method thereof. The inorganic salt containing tetravalent chromium is immersed in molten sodium hydroxide for reaction, magnesium oxide is separated to obtain an ammonium complex containing nickel and chromium, and then an oxidation assistant, a cobalt source and amanganese source are added, ball milling is performed, then a chromium-doped NCM precursor is prepared by a co-precipitation method, and after pre-burning, grinding and crushing, the chromium-doped NCM precursor is mixed with a powdery lithium source to carry out oxygen-enriched solid phase sintering, so as to obtain the chromium-doped high-voltage high-nickel ternary lithium battery positive electrode material. According to the method, a stable nickel layer structure is formed through tetravalent chromium and trivalent nickel, and meanwhile, the tetravalent chromium is subjected to disproportionation into mixed valence state in the sintering process, the problem that nickel ions are separated from the crystal lattices due to excessive oxidation is effectively solved, the prepared high-nickel ternary positive electrode material is good in cycling performance and good in high-temperature performance, the capacity loss of the lithium battery is small, the safety and the stability are good, and the application prospect is good.

Description

technical field [0001] The invention relates to the field of lithium batteries, in particular to the preparation of lithium battery cathode materials, in particular to a chromium-doped high-voltage, high-nickel ternary lithium battery cathode material and a preparation method. Background technique [0002] In recent years, due to the vigorous promotion of new energy vehicles, lithium-ion batteries have received widespread attention. Lithium-ion batteries have the advantages of high voltage, high energy density, long cycle life, and low environmental pollution. However, with the rapid development of electronic information technology, higher requirements are placed on the performance of lithium-ion batteries. Cathode material is currently the most critical material in lithium-ion batteries, and its development deserves the most attention. At present, the main research object of cathode materials for lithium-ion batteries is high-nickel ternary cathodes, whose main advantages l...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the current widely used high-nickel ternary cathode materials for lithium batteries, there are problems such as poor ring performance, poor high temperature performance, serious capacity loss caused by lithium batteries in the process of deep charge and discharge, poor cycle formation, low safety, and poor stability. , the present invention proposes a chromium-doped high-voltage high-nickel ternary lithium battery positive electrode material and a preparation method, thereby significantly improving the cycle performance and high-temperature performance of the high-nickel ternary complete machine material, and ensuring the capacity of the lithium battery. Good security and stability