All-solid-state lithium ion electrolyte material and preparation method thereof

Abstract

The invention provides an all-solid-state lithium ion electrolyte material and a preparation method thereof. The method specifically comprises the following steps: (1) adding a lithium source, an aluminum source, a titanium source and a phosphorus source into a water solution of ethanol according to a stoichiometric ratio of Li<1+x>Al<x>Ti<2-x>(PO4)3, wherein x is greater than 0 and less than or equal to 1, then adding a complexing agent, and carrying out hydrolyzing to obtain a uniform solution, sol or turbid liquid; (2) carrying out spray drying on the solution, sol or turbid liquid obtainedin the step (1); and (3) heating the product obtained in the step (2) to 600-1200 DEG C in an air atmosphere, carrying out temperature-control calcinations for 2-10 hours, and then carrying out natural cooling to obtain the walnut-like fast-ion conductor material titanium aluminum lithium phosphate. The all-solid-state lithium ion electrolyte material prepared by the preparation method is in a special morphology, is distributed in a monodisperse manner and has relatively high room-temperature ionic conductivity and excellent rate and cycle performance; and no other impurity elements are introduced, so that the product purity is high.

Description

technical field [0001] The invention relates to the field of lithium ion battery materials and preparation methods thereof, in particular to an all-solid lithium ion electrolyte material and preparation methods thereof. Background technique [0002] Lithium-ion batteries have been invented since the 1990s, and their popularity has grown rapidly. However, traditional commercial lithium-ion batteries are mainly lithium-ion batteries assembled with organic electrolytes. The non-aqueous system of electrolyte lithium salts and the physical and chemical properties of the metal shell make lithium-ion batteries prone to fires under long-term use and high temperature conditions. A series of safety hazards such as electrolyte leakage, short circuit and explosion, and the electrolyte will react severely with the electrode interface when the battery is working, resulting in poor cycle and rate performance of the battery. Therefore, if the battery does not contain or contains a small amo...

AI Technical Summary

Problems solved by technology

The whole process steps take too long, and the conductivity of the final electrolyte material needs to be improved

Chinese patent publication number CN103496740A has reported a kind of molten salt method to prepare Li 7 La 3 Zr 2 o 12 The method of electrolyte powder, which uses KCl and LiCl as molten salt, although the sintering temperature can be appropriately reduced, but the molten salt is easily mixed into the powder after sintering, which is difficult to wash off, resulting in low product purity

In this method, amorphous silicon oxide is used to improve the grain boundary conductivity of LLTO, but the added nano-silicon oxide layer is a lithium ion insulator, which has a limited effect on improving the grain boundary conductivity and total conductivity.

[0006] At present, it is basically the research on the above LLZO solid electrolyte and LLTO solid electrolyte materials, all of which have disadvantages such as poor electrochemical performance and low product purity.

In the prior art, there is no relevant report on the new type of electrolyte material-fast ion conductor lithium titanium aluminum phosphate

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