Method for preparing lithium cobaltate by directly using invalid lithium ion battery

Abstract

The invention provides a method for preparing lithium cobaltate by directly using an invalid lithium ion battery. The method comprises the following steps: crushing the invalid lithium ion battery or scraps generated when a lithium cobaltate battery is produced by a mechanical crusher at normal temperature; adding water and one or more of acetic acid, sulfuric acid, hydrochloric acid or nitric acid to produce mixed aqueous solution of the battery scraps and acid; filling the mixed aqueous solution into a hermetic pressure reactor, and controlling the temperature in the reactor to be between 50 and 150 DEG C; introducing or adding one leaching additive of sulfur dioxide or hydrogen, or adding hydrazine hydrate; stirring and leaching, cooling, and filtering; adding one precipitator of sodium carbonate, potassium carbonate and ammonium carbonate, or adding composite precipitator consisting of one of the sodium carbonate, the potassium carbonate and the ammonium carbonate and one of sodium hydroxide and potassium hydroxide to obtain mixture of lithium carbonate, cobalt carbonate and cobalt hydroxide; drying and calcining at high temperature to produce a lithium cobaltate product. The method is particularly suitable for the treatment scale of medium-sized and small enterprises, and is an effective method for directly materializing cobalt secondary resources.

Description

technical field [0001] The invention relates to a method for directly preparing lithium cobaltate by using a failed lithium ion battery, and belongs to the technical fields of nonferrous metal resource recycling and battery material preparation. In particular, the treatment method involving lithium cobalt oxide as the positive electrode material of the invalid lithium ion battery and the leftover waste does not go through many pretreatment procedures for separating the positive electrode material, and uses special leaching means to make lithium and cobalt elements enter the solution, and then remove them from the solution. Lithium and cobalt are precipitated in the medium, and lithium cobaltate is prepared by roasting, which provides an unlimited scale method for direct materialization of failed lithium-ion batteries. technical background [0002] Cobalt is a strategic metal resource that is in short supply in China. It is one of the metals with the highest dependence on for...

AI Technical Summary

Problems solved by technology

The solvent used to dissolve the binder with an organic solvent is expensive, and it is also difficult to separate the electrode material from other materials in the battery

The use of roasting pretreatment to remove organic matter is relatively simple, reducing the separation process and equipment of electrode materials, and obtaining metal-containing roasted products, but roasting will produce severely toxic gases such as hydrogen fluoride, dioxins, and furans, polluting the environment, and A large number of new cobalt-containing phases are produced, such as tricobalt tetroxide, etc., which are difficult to leach and extract, which is not conducive to the recovery of cobalt. It also makes tin-lead solder easy to leach during roasting, which increases the impurity content of subsequent solutions.

At present, there are different processes and methods in China. There are many types of chemicals used in recycling metals, the process is long, the waste generation is large, and the cost is high.

In addition, due to the difficulty in collecting failed lithium-ion batteries in China, it is difficult to meet the requirements of large-scale centralized processing, and the scale of general processing enterprises is generally small

[0013] Due to the special structure of lithium-ion batteries, the main valuable substance - lithium cobalt oxide is closely bonded to the aluminum foil current collector, which is not only difficult to disassemble and break, but also causes serious mechanical entrainment loss of lithium cobalt oxide during screening and magnetic separation. The rate is very low, which is the main reason for the low comprehensive recovery rate of cobalt, copper and lithium in the whole process, and the efficiency of the current general treatment method is also low

Taking the amorphous citrate precipitation method as an example, the comprehensive recovery rate of the valuable metals cobalt, copper, and lithium is only about 50%, and due to many processing procedures, the various reagents used are relatively expensive, and the processing cost is relatively high