Method for regenerating failure electrolyte of all-vanadium redox flow battery

Abstract

The invention relates to a method for regenerating a failure electrolyte of an all-vanadium redox flow battery. The technical scheme is as follows: the preparation method comprises the steps of proportioning a carbon material, anion exchange resin, a binder and an organic solvent in a mass ratio of 1: (0.1 to 1): (0.05 to 0.5): (2 to 10), and uniformly mixing to obtain a mixed solution I; preparing a carbon material, cation exchange resin, a binder and an organic solvent according to a mass ratio of 1: (1 to 5): (0.05 to 0.5): (2 to 10), and uniformly mixing to obtain a mixed solution II; respectively spraying or smearing the mixed solution I and the mixed solution II on a graphite felt electrode and drying; placing the dried anode composite electrode and cathode composite electrode at a positive electrode end and a negative electrode end corresponding to a capacitive deionization device, and circularly pumping the failure electrolyte of the all-vanadium redox flow battery into the capacitive deionization device under the condition of direct-current voltage to obtain an electrolyte I; and adding a chelating agent into the electrolyte I, and mixing to obtain the regenerated electrolyte. The regenerated electrolyte prepared by the method is low in impurity content and good in stability and electrochemical performance.

Description

technical field [0001] The invention belongs to the technical field of vanadium battery electrolyte. In particular, the invention relates to a method for regenerating an exhausted electrolyte of an all-vanadium redox flow battery. Background technique [0002] Vanadium battery is a new type of green and pollution-free chemical energy storage battery. Compared with other energy storage batteries, vanadium batteries have the characteristics of long operating life, low operation and maintenance costs, high reliability, strong safety and easy large-scale application. As an important part of the vanadium battery, the vanadium battery electrolyte is the energy storage active material of the vanadium battery. The performance of the vanadium battery electrolyte directly determines the performance of the vanadium battery. However, after long-term operation of the vanadium battery, the impurity ions in the electrolyte continue to accumulate, which leads to the failure of the electro...

AI Technical Summary

Problems solved by technology

Although this method can eliminate the influence of trace impurity ions, the effect is not ideal when the concentration of impurity ions in the electrolyte is high. Therefore, when the concentration of impurity ions in the electrolyte is high, it is necessary to consider preliminary impurity removal.

[0005] To sum up, the current method for regenerating the exhausted electrolyte of all-vanadium redox flow batteries generally adopts the method of diluting and adjusting the pH to precipitate vanadium to recover vanadium, which has complex process, high processing cost, and the recovery rate of vanadium cannot reach 100%. Produce waste water and waste gas to pollute the environment; and the method of adding complexing agent to the electrolyte is not suitable for the situation where the content of impurity ions in the electrolyte is high