Production method of lithium ferric metasilicate anode material

Abstract

The invention relates to a preparation method of lithium iron silicate cathode material. In the method, ferric saline, Na2SiO3 and lye are added into a reactor in a flowing way; the pH value of the reaction system is controlled, so that the hysrolysis reaction between the ferric iron and the SiO3 can occur; the common deposit of iron and silicon is prepared by filtering and washing; the common deposit of iron and silicon, the lithium source compound, the oxalic acid solution and the carbon source compound are mixedto become pulp state; the Fe is reduced to be Fe through ball milling; the precursor material of lithium iron silicate can be prepared by drying; the precursor material is calcinated under the conditions with the protective atmosphere and at the low temperature to form the agglomerated acidic lithium-iron anode material which is composed of nanoparticles. The method has the strong process adaptability; the industrial production can be easily realized; and the product has higher density and excellent electrochemical properties.

Description

technical field [0001] The invention belongs to the field of electrochemistry, and relates to a preparation method of a lithium iron silicate cathode material for a lithium ion battery. Background technique [0002] The energy crisis and environmental pollution pose severe challenges to human survival, and finding clean and renewable secondary energy is an urgent task to be solved to realize the sustainable development of human society. Among many secondary battery systems, lithium-ion batteries have the advantages of high working voltage, high energy density, long cycle life, low self-discharge rate, and environmental protection, and have become the main trend of secondary battery development. [0003] At present, commercial lithium-ion battery cathode materials mainly use α-NaFeO 2 type layered LiCoO 2 , it has the advantages of easy synthesis and stable charge and discharge performance, but LiCoO 2 The synthesis requires a large amount of scarce and expensive cobalt me...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the problem that the traditional method of synthesizing lithium iron silicate positive electrode material is difficult to balance the material density and electrochemical performance, the present invention provides a hydrolysis co-precipitation-normal temperature reduction method to synthesize silicic acid according to the chemical characteristics of iron salt and silicate The method for lithium iron cathode material, the main steps include: iron, silicon hydrolysis co-precipitation, Fe 3+ Normal temperature reduction, low temperature roasting, etc.

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