Preparation method for high-capacity nanometer organic positive electrode material

Abstract

Disclosed is a preparation method for a high-capacity nanometer organic positive electrode material. The preparation method comprises the steps of 1, putting trimellitic anhydride, urea, nickel chloride hexahydrate and ammonium molybdate into a mortar to be mixed uniformly, putting the mixture into a drying oven to be dried, performing cooling and crushing and then adding a saturated solution of hydrochloric acid / sodium chloride, heating until reaching a slight boiling state, and then performing cooling, filtering and drying; 2, putting the synthesized and dried product into a sodium hydroxide solution to be heated, and then cooling the solution, mixing with deionized water, and adjusting pH by a hydrochloric acid solution, and after the product is fully precipitated, performing separation by filtering; 3, washing the product obtained in the step 2 by deionized water and methyl alcohol for many times, and then putting into a vacuum box to be subjected to evaporation to remove a little residual low-boiling-point impurity to finally obtain a carboxyl substituted phthalocyanine compound; and 4, mixing phthalocyanine active material and a conductive agent I2 based on a certain proportion and then putting into a ball grinding mill to be subjected to ball grinding, adding a mixed glue solution into the ball-grinded and sieved powder and performing ball grinding again; and coating an aluminum foil with a slurry solution to obtain the positive electrode material.

Description

[0001] 【Technical field】 [0002] The invention relates to the technical field of lithium batteries, in particular to a method for preparing a high-capacity nanometer organic cathode material. [0003] 【Background technique】 [0004] With the rapid development of energy storage power supply and electric vehicles, the development of lithium-ion batteries with high energy density has become one of the focuses of research. The improvement of the performance of lithium-ion batteries largely depends on the characteristics of the cathode material. At present, the widely used inorganic cathode materials generally have defects such as limited capacity improvement, high energy consumption in the production process, potential safety hazards, and high costs. Traditional inorganic materials also have the following disadvantages: the actual available specific capacity does not exceed 200mAh / g, and the room for improvement is very limited. They all use non-renewable mineral deposits as raw ...

AI Technical Summary

Problems solved by technology

At present, widely used inorganic cathode materials generally have defects such as limited capacity improvement, high energy consumption in the production process, potential safety hazards, and high costs.

Traditional inorganic materials also have the following disadvantages: the actual available specific capacity does not exceed 200mAh / g, and the room for improvement is very limited. They all use non-renewable mineral deposits as raw materials, and mining them at the same time consumes a lot of energy, which does not meet the requirements of sustainable development.

However, organic compound cathode materials have problems such as difficulty in dissolving in the electrolyte and low conductivity.

[0005] At present, the existing research on oxygen-containing organic compound cathode materials has carried out many improvement measures from the addition of conductive agents, lithium / sodium salination of carbonyl compounds, polymerization process of carbonyl compounds, etc., and achieved certain results, but there are still The following problems: ①Although the addition of conductive agent improves the solubility and conductivity to a certain extent, it will cause a significant decrease in electrode capacity; ②Although the lithium salinization measure can reduce the solubility, it will introduce additional non-electrochemical Active Li + -O - functional group, leading to a decrease in specific capacity, and the functional group Li + -O - The electron-donating effect of the corresponding small molecule conjugated carbonyl compound reduces the redox potential of the corresponding small molecule conjugated carbonyl compound, which is not conducive to the performance of the positive electrode material; ③Although the polymerization process can effectively reduce the solubility, it will introduce components without chemical activity (such as coupling Unit) leads to a decrease in specific capacity, and the low conductivity of the polymer and the large charge repulsion between the monomers cause a slower ion / electron transport rate, while the swelling of the polymer and its own aggregation during charge and discharge The state structure will also affect the diffusion and migration rate of lithium ions

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