Method for industrially producing lithium-iron-phosphate positive pole material

Abstract

The invention discloses a method for industrially producing a lithium-iron-phosphate positive pole material by utilizing low-price ferric iron sources as a reaction material. The method comprises the following steps of: synthesizing a lithium-iron-phosphate precursor: weighing a lithium source, an iron source and a carbon source according to a reaction ratio, transferring the lithium source, the iron source and the carbon source into mixing equipment, continuously mixing the materials for 1-5 hours, carrying out granular control on the mixed materials by utilizing a gas crushing machine after the mixing is finished; after the granularity of the materials is refined, compacting the materials by a compacting machine, and finally transferring the materials into a sintering furnace; after introducing inert and protective gas into the sintering furnace, carrying out sintering under the front-stage temperature of 300-400 DEG C; after the sintering is finished, naturally cooling to be at the room temperature; secondarily introducing the carbon source, weighing the organic carbon source according to the ratio of a cooled precursor material, remixing, and adding the mixed materials into the high-temperature sintering furnace again after being mixed uniformly; and the synthesizing a lithium-iron-phosphate material: introducing the inert gas for protecting the mixed materials which are added again, roasting under the temperature of 600-800 DEG C for 2-10 hours, and cooling, so as to obtain carbon-covered lithium-iron-phosphate positive pole material.

Description

technical field [0001] The invention relates to a production method of power-type new energy, in particular to a method for industrial production of lithium iron phosphate cathode material. Background technique [0002] In the environment of the shortage of primary energy and the increasingly serious environmental pollution, green and environmentally friendly lithium-ion secondary batteries are widely used because of their high specific energy, good cycle performance, safety and pollution-free. Among the cathode materials for lithium-ion batteries, lithium iron phosphate cathode materials are known as the most promising cathode materials. [0003] LiFePO with olivine structure 4 Because of its internal FeO 6 The octahedron is connected at the same point only at a certain angle, so it has disadvantages such as low conductivity, rate discharge, and low temperature discharge; currently, the common methods for producing lithium iron phosphate materials mainly include solid-pha...

AI Technical Summary

Problems solved by technology

[0005] The object of the present invention is to provide a kind of cheap ferric iron source as reaction raw material to prepare lithium iron phosphate material, can overcome the shortcoming that ferrous iron source is difficult to preserve and easy to oxidize Compared with the shortcomings of poor morphology and poor electrochemical performance of lithium iron phosphate materials prepared by using ferric iron source under conventional process conditions, the economical and efficient preparation process of lithium iron phosphate materials has been realized, and the ratio of lithium iron phosphate cathode materials has been improved. The industrial production method of lithium iron phosphate positive electrode material of capacity and electric conductivity

Images