Analyzing Discharge Characteristics of Redox Flow Battery using Hydrochloric Acid as a Reaactant

Abstract

This research focused on two-phase flow performance of a reactant in a cathode that used affordable, locally sold hydrochloric acid to provide low-pressure. The experimental characteristics including current density and cathode flow rate were set to 100 - 400 ml/min while concentration rate was set to 1 - 3 molarity and reaction area was set between 25 and 49 cm2. Electrode synthesis and cell performance were obtained in operation to validate the numerical results with comparison between the two substances, Pt/C and RuO2.The best performance was achieved at concentration of 2 M and a flow rate of 400 ml/min with a current density and power density exceeding 179 mA/cm2 and 3 mW/cm2, respectively. The limiting current density and power density for reaction area 49 cm2 was about 123 mA/cm2 and 98.1 mW/cm2, respectively, at 57.9% voltage efficiency. An increased average voltage efficiency for reaction area 25 cm2 was about 64.5%. The Pt/ C side Colleen to RuO2 catalyst loading resulted in decreasing average voltage efficiency (6.6 %). Hence, the investigation will be beneficial to determine the suitable performance of two-phase flow configuration for the redox flow battery with low-cost material and to gain in-depth understanding of operation characteristics of redox flow battery using hydrochloric acid as a reactant for the new model of two-phase flow in cathode.