Method for preparing electrolyte for vanadium redox flow battery using vanadium oxide

摘要

According to the method for preparing an electrolyte for a vanadium redox flow battery, one electrolyte can be used as both the positive electrolyte and the negative electrolyte, by preparing an electrolyte having a median oxidation number of electrolytes used for the positive electrode and the negative electrode of the vanadium redox flow battery. Particularly, since the mixed electrolyte having the median oxidation number is separated into the same amounts of positive electrolyte and the negative electrolyte at the time of charging and discharging, the maximum charging and discharging effect based on the supplied capacitance can be obtained.

主权项

1. A method for preparing an electrolyte for a vanadium redox flow battery by mixing two vanadium electrolytes having different oxidation numbers, the electrolyte having an oxidation number of +3.5 and being usable for both a positive electrode and a negative electrode, the method comprising:
conducting a first electrolyte preparing procedure of mixing vanadium oxide and an acidic solution to prepare a vanadium electrolyte having an oxidation number range of +3.5 to +5, as a first electrolyte; conducting a second electrolyte preparing procedure of mixing vanadium oxide and an acidic solution to prepare a vanadium electrolyte having an oxidation number range of +2 to +3.5, as a second electrolyte; conducting a mixed electrolyte preparing procedure of mixing the first electrolyte and the second electrolyte prepared by the first electrolyte preparing procedure and the second electrolyte procedure to prepare a mixed electrolyte; conducting a mixed electrolyte supplying procedure of supplying the prepared mixed electrolyte to a positive electrode and a negative electrode of a stack; conducting a positive electrolyte and negative electrolyte separating procedure of separating a positive electrolyte and a negative electrolyte from each other by supplying electric energy to the stack, further comprising after the mixed electrolyte preparing procedure, conducting a mixed electrolyte oxidation number checking procedure of checking the oxidation number of the mixed electrolyte by comparing the mixed electrolyte with a reference electrolyte having a median oxidation number of the first and second electrolytes used as the positive electrolyte and the negative electrolyte of the vanadium redox flow battery; and before the mixed electrolyte supplying procedure, conducting an oxidation number matching procedure of further adding the first electrolyte or the second electrolyte until the oxidation number of the mixed electrolyte, checked in the mixed electrolyte oxidation number checking procedure, is the same as the oxidation number of the reference electrolyte, the mixed electrolyte having the same oxidation number as the reference electrolyte being supplied to the stack in the mixed electrolyte supplying procedure.