Modified anode material and preparation method thereof as well as lithium ion battery

Abstract

The invention provides a preparation method of a modified anode material. The preparation method comprises the following steps: stirring an anode material and a hydroxyl alumina sol in water for reacting, and drying by distillation to obtain a powder product; roasting the powder product to obtain the modified anode material. According to the preparation method of the modified anode material, the hydroxyl alumina sol is adopted as an aluminum source to perform water cladding on the anode material; compared with the prior art that alumina is adopted to perform surface cladding on the anode material, the preparation method has the advantages that the attenuation of the cycle performance of the anode material caused by lithium loss due to water cladding cannot occur, the contact area between the anode material and electrolyte can be effectively reduced, the dissolving of the anode material in a high temperature cycling process is improved, and the cycling capacity keeping capability is enhanced; therefore, a lithium ion battery prepared by the modified anode material which is prepared by the method has better cycling performance and high temperature storage performance. The invention also provides the modified anode material and the lithium ion battery.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a modified positive electrode material, a preparation method thereof and a lithium ion battery. Background technique [0002] Energy is an important basis for the development and progress of human society, and the human demand for energy is increasing. It is estimated that the energy demand will increase by 50% to 100% by 2020. With the development of society, the problems of environmental pollution and energy crisis in our country are becoming increasingly serious, and the development and research of new energy power batteries have gradually received people's attention. Lithium-ion battery is a new type of high-energy battery with high specific energy and wide voltage, and is environmentally friendly. It has become an important direction for the development of my country's new energy industry. [0003] At present, the positive electrode material used in lithium-ion power batt...

AI Technical Summary

Problems solved by technology

[0003] At present, the positive electrode material used in lithium-ion power batteries is generally nickel-cobalt lithium manganese oxide positive electrode material. This positive electrode material has good reaction reversibility, strong high-current discharge capacity, and good cycle stability and safety. performance; however, the recycling performance of traditional nickel-cobalt lithium manganese oxide cathode materials can no longer meet the needs of the market. With the in-depth study of materials by researchers, it is found that the surface properties of cathode materials have a great influence on the electrochemical performance, especially for high-temperature performance and The cycle performance has a great influence, and the coating modification of the surface of the positive electrode material has become a research hotspot

[0004] The Chinese patent with the application number 201110222398.X discloses a method for preparing lithium-ion battery anode material wet-coated aluminum, which includes the following steps: preparing a precursor and preparing a slurry with a certain solid content; dissolving isopropanol in advance The aluminum isopropanol solution is added dropwise to the precursor slurry at a certain speed, and the appropriate dropping speed, temperature, and stirring speed are controlled; after the dropping is completed, it is aged for a certain period of time, filtered, washed, and dried to obtain the coated aluminum The nickel-cobalt-manganese precursor; the aluminum-coated precursor and the lithium salt are mixed evenly, and after a certain period of high-temperature treatment, cooling and crushing, the lithium-ion battery cathode material coated with aluminum isopropoxide in a wet method is obtained; the existing Although the lithium-ion battery positive electrode material coated with aluminum isopropoxide provided by the technology has improved the high-temperature safety performance and cycle characteristics of the lithium-ion battery prepared by the positive electrode material; Stability and high temperature storage performance need to be further improved

Images