PURPOSE: To prevent Coulomb efficiency of electrolyte for a redox flow battery from being lowered even if used for long time by after applying lead ions into solution, reducing the solution with electrolytic reduction by means of an electrolytic cell as solution potencial of the saturated calomel electrode-standard becomes lower than the specified value to efficiently remove nickel ions in the solution by electroanlysis.
CONSTITUTION: The supplied material is dissolved in acid solution including hydrochloric acid. The solution obtained during dissolution process is reduced with electrolytic reduction in a cathode room of an electrolytic cell under the existence of lead ions as solution potencial of the saturated calomel electrode standard becomes lower than -0.6V to remove nickel ions in the solution by electroanlysis. Thus, electrolyte producing cost is extremely lowered and charging/discharging efficiency having same level as that of highly pure chrome material is obtained. Furthermore, high Coulomb efficiency and potencial efficiency can be maintained.
UMEHARA YOICHI
MORIE SATSUKI
KUWABARA IKUROU
OKADA YOSHIMI
