Vanadium ion redox flow battery electrolyte, preparation method thereof and battery thereof

Abstract

The invention provides vanadium ion redox flow battery electrolyte, comprising vandic salt, sulphuric acid, additive, deionized water and metal salt can be dissolved in a sulphuric acid system. The electrolyte can greatly improve the cathode system evolution overpotential of the vanadium battery and anode system evolution overpotential, greatly reduce the ratio of gas evolution in the electrolyte caused by various polarizations in the process of operating the vanadium battery, and improve the stability of the electrolyte in the process of charge and discharge. The invention further provides a preparation method of the vanadium ion redox flow battery electrolyte, which eliminates a step of electrolyzing the obtained vanadyl sulfate solution to obtain 50% of trivalent vanadium and 50% of tetravalent vanadium, greatly simplifies the manufacture technology of the vanadium electrolyte which can be directly used for charging and discharging, reduces the lose of the vanadium in the process of preparation, and reduces the preparation cost of the electrolyte.

Description

technical field [0001] The invention relates to an electrolyte of a liquid flow battery, a preparation method thereof, and a battery, in particular to an electrolyte of an all-vanadium ion flow battery, a preparation method thereof, and a battery using the electrolyte. Background technique [0002] The all-vanadium redox flow battery is a redox flow battery in which the active material is in a cyclic flow state. It was first proposed by the University of New South Wales in Australia. After more than ten years of development, the relevant technologies have become mature, and Japan, the United States, Australia, and Canada have completed their practical research and realized industrial applications. Since the active material of the vanadium battery is stored in the liquid storage tank outside the stack, compared with the traditional solid-phase battery, it has the advantages of small concentration polarization, large battery capacity, easy adjustment, long life, and can withst...

AI Technical Summary

Problems solved by technology

[0004] The main problem that the method for above-mentioned preparation vanadyl sulfate solution exists is: (1) with elemental sulfur or SO Reduction, these materials itself are not friendly to the environment, with oxalic acid reduction, excessive oxalic acid is difficult to get rid of, so just It will affect the quality of the electrolyte; it needs to be fired at high temperature, the reaction conditions are harsh, and the requirements for equipment are high

Most of the attention is now on the first aspect of stability. For example, the prior art discloses adding some substances in the electrolyte that can make vanadium ions exceed the limit concentration in the electrolyte without precipitation or precipitation, including organic or inorganic substances. substances, liquids or solids; studies on the stability of the second aspect have not been reported