Thermal polymerization preparation method of manganides solid solution positive material

Abstract

The invention relates to a thermal polymerization preparation method of a manganides solid solution positive material. The thermal polymerization preparation method comprises the following steps of: preparing a mixed solution comprising lithium salt, nickel salt and manganese salt according to a general form stoichiometric proportion; adding a thermal polymerization precursor solution to the mixed solution; stirring the mixed solution to polymerize to form a gelatinous material at the temperature of between 80 DEC and 120 DEC and pH of between 4 and 7; drying the obtained gelatinous material in vacuum at the temperature of between 140 DEC and 170 DEC to obtain a resinoid product; pre-burning the resinoid product for 5 to 20 hours at the temperature of between 400 DEC and 700 DEC; carrying out heat preserving on the resinoid product for 5 to 20 hours at the temperature of between 750 DEC and 1000 DEC; and slowly cooling the product to a room temperature after calcination to obtain a finished product. According to the thermal polymerization preparation method, the raw material component blending can reach to molecule degree level, larger nonuniformity of microcosmic material matching ratios by blending with a mechanical method can be avoided; the thermal polymerization preparation method is easy and simple to operate; and the synthetic product is fine and uniform in grain diameter, high in purity, higher in discharge ratio capacity, excellent in circulating performance and high temperature performance and remarkable in magnification performance and can serve as a high power lithium ion battery positive material.

Description

technical field [0001] The present invention relates to the positive electrode material technology for lithium-ion secondary battery, especially manganese series solid solution positive electrode material Li[Ni x Li (1-2x) / 3 mn (2-x) / 3 ]O 2 (0≤x≤0.5), the material prepared by the method can be applied to the positive electrode of lithium ion battery. Background technique [0002] As the core of electric vehicles, the mainstream direction of power batteries is lithium-ion power batteries. The positive electrode material of existing commercial lithium-ion secondary batteries uses lithium cobalt oxide (LiCoO 2 ), ternary class (LiNiMnCoO 2 ), lithium manganate (LiMn 2 o 4 ), lithium iron phosphate (LiFePO 4 )Wait. However, the theoretical capacity of these cathode materials is less than 200mAh / g, which makes it difficult for the market development of 3G electronic products and electric vehicles that require high battery capacity. Therefore, it is necessary to explore a ...

AI Technical Summary

Problems solved by technology

[0006] From the existing literature and patents, it can be seen that the mainstream preparation process of lithium-rich solid solution cathode materials is co-precipitation combined with solid-phase method, and the material has high discharge potential and electrochemical capacity. PH adjustment, filtration, washing and other processes lead to poor consistency of product performance, large initial irreversible capacity of the sample and unsatisfactory rate performance

Images