Method for preparing lithium titanate by spray drying-solid phase method

Abstract

The invention discloses a method for preparing lithium titanate by a spray drying-solid phase method, the method comprises the following steps: (1) weighing a titanium source, adding ammonia water, preparing metatitanic acid under a first reaction condition, adding concentrated nitric acid, and ultrasonically preparing a titanium oxynitrate clear solution; (2) weighing a lithium source, adding a dispersant and deionized water, and stirring to obtain a first solution; (3) mixing the titanium oxynitrate clear solution with the first solution, and then drying with a spray drier to obtain precursor powder; and (4) roasting and cooling the precursor powder to prepare the lithium titanate. According to the method, the lithium titanate is prepared by a method spray drying and solid phase combinedmethod, and the prepared lithium titanate is uniform and non-heterogenous micro-nano spherical lithium titanate particles, and the lithium titanate particles have high diffusion degree, good chemicaluniformity, atomic-level uniform distribution and high tap density. The lithium titanate can slow down the polarization of a electrode and increase the contact area between an electrode material andan electrolyte.

Description

technical field [0001] The invention relates to the field of lithium ion batteries, in particular to a method for preparing lithium titanate by a spray drying-solid phase method. [0002] technical background [0003] Lithium-ion batteries have the advantages of environmental protection, light weight, large capacity, and no memory effect, and have been widely used in various electronic products. At present, the anode materials of lithium-ion batteries on the market are mainly graphite. However, there are several problems with graphite: 1. The ion diffusion coefficient of graphite is low, which leads to unsatisfactory rate performance of graphite anode lithium-ion products. 2. The graphite negative electrode will undergo a certain volume expansion during the process of deintercalating lithium. At the same time, the SEI film formed on the surface of the graphite negative electrode is a dynamic process of continuous consumption and repair during the charging and discharging proc...

AI Technical Summary

Problems solved by technology

At present, the anode materials of lithium-ion batteries on the market are basically graphite, but graphite has several problems: 1. The ion diffusion coefficient of graphite is low, which leads to unsatisfactory rate performance of graphite anode lithium-ion products

2. The graphite negative electrode will undergo a certain volume expansion during the process of deintercalating lithium. At the same time, the SEI film formed on the surface of the graphite negative electrode is a dynamic process of continuous consumption and repair during the charging and discharging process. Therefore, the battery using the graphite negative electrode The problem of cycle capacity fading remains to be overcome

3. The potential platform of graphite deintercalation lithium is about 0.1 ~ 0.15V, it is easy to form lithium precipitation at low temperature or high magnification, leading to safety accidents

The process of synthesizing nano-scale powder by sol-gel method is relatively complicated, while the solution combustion method uses glycine complexation. Although the performance of the synthesized nano-powder is better, the price of glycine complexing agent is relatively high, and the cost is greatly increased. In addition, the The reaction process is violent and difficult to control

The solid-state reaction method is one of the traditional methods for preparing spinel lithium titanate, which uses TiO 2 with LiOH·H 2 O or Li 3 CO 3 Lithium titanate is obtained by sintering at high temperature under nitrogen atmosphere after mixing, which has the advantages of simple process and low cost, but at the same time, there are problems that the powder raw materials need to be ground and mixed for a long time, the uniformity is limited, and the diffusion process is difficult to proceed smoothly. , at the same time, the preparation process of this method requires high-temperature sintering in a nitrogen atmosphere, and the sintering time is relatively long, which makes it difficult to realize in the actual production process

Images