Positive electrode material for lithium ion battery and preparation method of positive electrode material

Abstract

The invention discloses a positive electrode material for a lithium ion battery as well as a preparation method and application of the positive electrode material. Slurry prepared from the positive electrode material for the lithium ion battery is still stable after being arranged for a period of time and cannot be gelled, and therefore, a positive electrode piece can be prepared easily; meanwhile, the positive electrode material has excellent cycle performance at high temperature and under high voltage. According to the method for preparing the positive electrode material for the lithium ion battery, a microwave absorbent is added so that raw materials can be synthesized and subjected to coating reaction under a relatively high microwave power without secondary high-temperature annealing, and the added microwave absorbent which is taken as the raw material of the coating does not need to be removed, preparation operation is simple and industrial practicability is achieved.

Description

technical field [0001] The invention relates to the field of lithium ion battery preparation, in particular to a modified lithium ion battery positive electrode material and a preparation method thereof. Background technique [0002] With the continuous expansion of the application field of lithium-ion secondary batteries, especially the application in mobile phones, notebook computers and electric vehicles, etc., the development of lithium-ion secondary battery materials has brought broad prospects. The performance and price of battery materials also put forward higher requirements. Among them, the most urgent requirement is to improve the energy density of lithium-ion batteries while ensuring the safety performance of lithium-ion batteries. [0003] There are two main ways to increase the energy density of lithium-ion batteries. One is to increase the capacity of lithium-ion battery electrode materials, and the other is to increase the operating voltage of lithium-ion batt...

AI Technical Summary

Problems solved by technology

[0008] In the prior art, oxides are used as microwave catalysts for ester hydrolysis, Diels-Alder reactions and benzyl substitution reactions. For example, Chinese patent CN101172224A discloses a method for promoting chemical reactions under microwave radiation conditions. SnO 2 or Fe 3 o 4 As a high-efficiency microwave absorber, it is used to catalyze liquid organic reactions, but the SnO used in this method 2 or Fe 3 o 4 Only as a microwave absorber, when the reaction is over, it needs to be separated by filtration or column chromatography, and its promotion effect on microwave-catalyzed solid-phase reactions is not good

[0009] At the same time, there are doped and surface-coated lithium ion positive electrode materials and their preparation methods in the prior art, such as Chinese patent CN102332585A, which discloses a lithium nickel cobalt manganese oxide / tin oxide composite positive electrode material doped with metal elements and its Preparation method, the chemical expression of the lithium nickel cobalt manganese oxide / tin oxide composite positive electrode material doped with metal elements is: LiNi x co y mn z R z′ o 2 / SnO 2 , wherein, 0.1≤x≤0.7, 0.1≤y≤0.7, 0.1≤z≤0.7, 0.001≤z≤0.2, said x+y+z+z'=1, the composite cathode material at room temperature, 2.5 The 20-cycle capacity retention rate between ~4.3V is 78-81%, and the cycle capacity retention rate at high temperature and high voltage will be lower, and the composite positive electrode material is prepared by high-temperature solid-state reaction, which requires a long time Time high temperature reaction, not only consumes a lot of energy, but also takes a long time to react