A kind of preparation method of iron phosphate doped with nano-titanium dioxide

Abstract

The invention discloses preparation of iron phosphate doped with nanometer titanium dioxide. The preparation comprises the following steps: adding iron powder and titanium tetrachloride liquid into hydrochloric acid, then adding an oxidizing agent till the molar ratio of ferrous ions to ferric ions in a solution is 1:2, then adding into a high-temperature sealed furnace in a spraying way, reactingat 700-800 DEG C, then sucking out through a suction fan, cooling, then collecting solid ferroferric oxide particles doped with the nanometer titanium dioxide, then adding into a phosphoric acid solution, reacting till the black color completely disappears, then filtering, washing and drying, performing electromagnetic separation, and then sieving to obtain the iron phosphate doped with the nanometer titanium dioxide. The nanometer titanium dioxide is uniformly distributed in the iron phosphate, the primary particle sizes of the obtained iron phosphate and the nanometer titanium dioxide are about 30 nanometers, the secondary particle sizes thereof are 400-600 microns, wastewater produced by each ton of the product is less than 10 tons, the wastewater does not contain ammonia nitrogen, andthe cost is low.

Description

technical field [0001] The invention relates to a method for preparing ferric phosphate doped with nano-titanium dioxide, and belongs to the technical field of lithium battery material preparation. Background technique [0002] In today's era, in order to alleviate the global energy crisis, environmental crisis and get rid of the financial crisis, developed countries in Europe and the United States, Japan and China have focused their technological innovation on the new energy industry. In the process of searching for new energy sources, lithium-ion batteries, as a new generation of clean and environmentally friendly energy sources, have received more and more attention. [0003] For lithium-ion batteries, positive and negative electrode materials are the key factors that determine their electrochemical performance, safety performance, and price and cost. Nano-titanium dioxide has the characteristics of large lithium intercalation capacity, low toxicity, low energy consumpti...

AI Technical Summary

Problems solved by technology

[0006] 2. Low tap density and poor low-temperature performance: the surface is coated with nano-titanium dioxide to make LiFePO 4 Improved low temperature performance

[0008] 4. Slow diffusion of lithium ions: pure LiFePO 4 The room temperature conductivity of the cathode material is low, Li + Diffusion coefficient is small, it is difficult to be practical

[0009] At present, conventional doped nano-titanium dioxide is mainly divided into two types, one is mechanical doping, and nano-titanium dioxide is mechanically doped with iron phosphate. Since the doping amount of nano-titanium dioxide is very small, generally less than 1%, it leads to doping Miscellaneous is difficult to evenly

The second is to achieve doping by co-precipitation, but because titanium is tetravalent, the pH of its precipitation is much lower than that of iron ions, resulting in the segregation of titanium

Images