Recycling method for electrolyte in waste power lithium ion battery

Abstract

The invention discloses a recycling method for an electrolyte in a waste power lithium ion battery. The recycling method comprises the following steps of (1) cutting the waste power lithium ion battery under protection of nitrogen, removing a shell, taking out a battery cell, and cutting the battery cell; (2) adding dichloroethane into the cut battery cell debris for leaching, and performing negative-pressure filtering to obtain a leaching liquid; (3) performing normal-pressure distillation on the leaching liquid under a condition of 35-50 DEG C, and performing cooling, backflowing and recycling to obtain dichloromethane; and (4) performing pressure-reduction distillation separation on the backflown remaining liquid under the condition of vacuum being 1,000pa and 80 DEG C to obtain an electrolyte organic solvent and an electrolyte lithium hexafluorophosphate. The method is used for recycling the electrolyte in the waste power battery, is simple in process and high in recycling efficiency, and no pollution to an environment is generated.

Description

technical field [0001] The invention relates to the field of battery recycling, in particular to a method for recycling electrolyte in waste power lithium-ion batteries. Background technique [0002] The application of lithium-ion batteries in consumer electronics and electric vehicles has experienced leapfrog development. In the 10 years from 2000 to 2010, the annual output of lithium-ion batteries increased at a rate of 800%. It is estimated that by 2020, there will be more than 25 billion waste lithium-ion batteries, totaling about 500,000 tons. Although the large-scale recycling enterprises of waste batteries in my country are gradually emerging, in the research of recycling lithium power batteries, including positive and negative materials, separators , the recycling of the five major components of the shell and the electrolyte has been studied at home and abroad, and the methods for the first four materials are relatively simple, environmentally friendly and safe, and t...

AI Technical Summary

Problems solved by technology

[0003] Lithium-ion electrolyte is an organic liquid, which will absorb water and deteriorate in the air. At the same time, it contains toxic components, which will pollute the environment if leaked in the air; the battery will have capacity decay and deterioration during use. In order to extract the problem battery For the analysis and research of the electrolyte, it is necessary to separate the electrolyte in the battery. The existing technology is to simply extract the electrolyte in the battery pole piece. Since the electrolyte and the positive and negative pole pieces are in an infiltrated state, it is not easy to separate and simple. The disadvantage of extraction is that it is difficult to collect, the amount of collection is small, and the collected electrolyte is thin and uneven, which makes the analysis and research inaccurate; at the same time, the treatment of waste batteries is usually to incinerate the battery, and the residual electrolyte will be gasified and discharged. On the one hand, it causes a waste of electrolyte, and at the same time causes certain pollution to the environment