Washing method of ternary precursor

Abstract

The invention provides a washing method of a ternary precursor, which is characterized in that through multi-stage alcohol washing, on the premise of ensuring that various properties of a washed to-be-dried material are equivalent to those of a to-be-dried material in a conventional washing process, moisture contained in the to-be-dried material is less, and the to-be-dried material is easier to dry. According to the washing method of the ternary precursor, a washing procedure in a back-end program of an existing washing procedure is replaced by at least two stages of echelon multi-stage washing procedures, and the mass fraction of an alcoholic solution in the back washing procedure is higher than that of an alcoholic solution in the front washing procedure. The washing process follows the basic principle of washing for a small amount and multiple times, the washing consistency is better, and on the premise that it is guaranteed that all properties of the washed to-be-dried material are basically equivalent to those of the to-be-dried material in the conventional washing process, moisture contained in the to-be-dried material is less, and the to-be-dried material is easier to dry.

Description

technical field [0001] The invention belongs to the technical field of battery preparation, and in particular relates to a washing method of a ternary precursor. Background technique [0002] Lithium-ion battery cathode material is a decisive factor affecting the electrochemical performance, safety and cost of the entire battery. Among related technologies, the most widely commercialized lithium-ion battery cathode material is LiNi x co y mn 1-x-y o 2 Ternary material. [0003] At present, the preparation methods of ternary cathode materials mainly include high-temperature solid-phase method, liquid-phase co-precipitation controlled crystallization method, sol-gel method, spray pyrolysis method and hydrothermal method. At present, most enterprises use the liquid-phase co-precipitation controlled crystallization method for large-scale production of ternary material precursors. This method combines soluble transition mixed metal salts (nickel, cobalt, manganese or aluminum...

AI Technical Summary

Problems solved by technology

At present, most enterprises use centrifuges or filter presses when washing the precursors of ternary materials. 4 2- ions, and then wash off the excess metal cations and obtain the material to be baked. The current technology can control the pH of the reaction section, the washing amount of alkaline washing and water washing in the washing section, the washing temperature, etc., to wash off most of the impurity ions. Control within a reasonable range, however, the water content in the material to be dried after washing is often easily ignored. Even if you notice this and constantly adjust the process parameters of the washing equipment, the water content in the material to be dried is still high

The high water content in the material to be dried not only makes it difficult to unload the material in the washing section, but also causes difficulties in the transfer of the material to be dried, that is, the transfer of the material to be dried from the washing equipment to the drying equipment, and also causes certain damage to the drying equipment. Damage, greatly prolonging the baking time and increasing the cost of baking

In recent years, there has been a method of introducing an alcohol washing step to reduce the moisture content. However, after the introduction of this step, the washing consistency cannot be guaranteed, and the BET of the product has increased significantly.

Images