METHOD OF MEASURING AVERAGE OXIDATION DEGREE AND CONCENTRATION OF VANADIUM IONS IN ELECTROLYTE OF VANADIUM FLOWING REDOX BATTERY AND INSTALLATION FOR IMPLEMENTATION THEREOF Russian patent published in 2024 - IPC H01M8/18 

FIELD: electrical engineering.

SUBSTANCE: invention relates to a method and a device for determining the average degree of oxidation and concentration of vanadium ions in an electrolyte of a flow vanadium redox battery by coulometry and can be used to produce electrolyte for vanadium flow battery. Technical result is achieved by the fact that in a flow-through electrochemical cell with a proton-exchange membrane and a gas-diffusion hydrogen electrode, spent charges are measured in the process of electrooxidation of a sample of the analysed vanadium electrolyte with any ratio of concentrations of redox forms of vanadium to an oxidation state of +5, followed by electroreduction of the analysed sample to an oxidation state of +4, wherein electrooxidation and electroreduction is carried out in the presence of a background electrolyte based on sulfuric acid or hydrochloric acid in a volume ratio of the sample of the analysed electrolyte and the background electrolyte of 1:10, for which preliminary measurements of consumed charge for electrooxidation and electroreduction are carried out, after which the degree of oxidation and content of vanadium in the analysed solution are determined. Amount of passed charge (in C) at stages of electrooxidation and electroreduction with specified modes of constant voltage and current density is used to calculate concentration and degree of oxidation. Apparatus for implementing the disclosed method with a potentiostat includes a flow-through electrochemical cell with a proton-exchange polymer membrane separating a vanadium half-cell and hydrogen half-cell with electrodes from porous carbon materials with applied catalyst layer for hydrogen half-cell, hydrogen generator with hydrogen humidifier, reservoir with electrolyte and nozzles for inlet and outlet of electrolyte supplied to measuring cell by means of pump.

EFFECT: determination of average degree of oxidation and total concentration of vanadium ions in vanadium electrolytes at any state of charge of the battery against the background of additives of mineral acids of different nature and concentration.

4 cl, 5 dwg, 2 tbl