Method for preparing lithium tetrafluoroborate

Abstract

The invention relates to a method for preparing lithium tetrafluoroborate. The method comprises the following steps of dissolving solid lithium carbonate with the purity higher or equal to 99.9% into pure water so as to prepare a suspension, heating the suspension, adding a fluoroborate aqueous solution to the heated suspension so as to react, carrying out filtering, evaporative concentration, cooling crystallization, separation and drying on a material after the reaction is completed, dissolving the dried material in a protection cabinet with nitrogen gas by adding anhydrous ethanol, crystallizing, and drying, thereby obtaining white powdery lithium tetrafluoroborate. The method disclosed by the invention has the advantages that the used raw materials are rich and are easy to obtain, the production cost is low, the process is simple, the operation and control are simple and convenient, the reaction rate is high, and the obtained lithium tetrafluoroborate product has the purity over 99% and the moisture lower than 200 ppm and meets the production needs of lithium-ion electrolysis tanks.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a preparation method of lithium tetrafluoroborate. Background technique [0002] Lithium-ion batteries have outstanding advantages such as high working voltage, high energy density (light weight), low self-discharge rate, no memory effect, long cycle life and no pollution. In recent years, it has quickly occupied many fields with its incomparable advantages over other batteries, and is widely used in well-known mobile phones, notebook computers, small cameras, electric vehicles and other products. With the industrialization of electric vehicles, the amount of lithium-ion batteries is bound to increase. The application shows that lithium-ion battery is an ideal small green power source. [0003] Electrolyte is an indispensable part of the electrolyte of lithium-ion batteries and one of the determinants of the performance of lithium-ion batteries. Therefore, improvi...

AI Technical Summary

Problems solved by technology

The non-aqueous solution method is to form a suspension in an organic solvent, and then react to form a product. It uses an organic solvent, which has side reactions and produces a tightly combined intermediate compound, which is difficult to separate.

The aqueous solution method uses acids to react with basic lithium salts, concentrates, crystallizes, filters, dries, and then recrystallizes to obtain a relatively pure product. However, the aqueous solution method uses an inorganic medium to purify lithium tetrafluoroborate, and there are product dehydration, purification, and separation. Difficulty and other problems, its production cost is also high