Characteristics of the all-vanadium redox flow battery using anion exchange membrane

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2014-11, Vol.45 (6), p.2920-2925
• Main Authors: Choi, Ho-Sang, Oh, Yong-Hwan, Ryu, Cheol-Hwi, Hwang, Gab-Jin
• Format: Article
• Language: English
• Subjects: Cell performance; Energy storage; Ion exchange membrane; Redox flow battery; Vanadium
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2014.08.032

•A three commercial anion exchange membrane was evaluated for the application as a separator in the all-vanadium redox flow battery (V-RFB).•AFN membrane (ASTOM Co.) was selected as a separator in V-RFB with its largely unchanged membrane resistance during durability test.•AFN membrane had a good performance as a separator in V-RFB.•An average energy efficiency in V-RFB using 1M VOSO4 in 2M H2SO4 and 2M VOSO4 in 4M H2SO4 solution were 72.0% and 74.8%, respectively. Three commercial anion exchange membranes were evaluated the chemical stability with an increase of soaking time in a pentavalent vanadium ion (VO2+) solution. The membrane resistances of anion exchange membranes in 1M (mol/L) H2SO4 aqueous solution were measured as an indicator of chemical stability. AFN membrane (ASTOM Co., Japan) was selected as a separator in an all-vanadium redox flow battery (V-RFB). The cell performance of V-RFB using AFN membrane was measured at a current density of 60mA/cm2. The cell resistance for the charge had almost the same value (in the range of 3.47–3.67Ωcm2) with an increase in the state of charge (SOC). For the discharge, the cell resistance had almost the same value (in the range of 2.00–2.25Ωcm2) with an increase in the state of discharge (SOD). The cell efficiency of the V-RFB using the AFN membrane was evaluated at each cycle. The average energy efficiency was 72.0%. Thus, the AFN anion exchange membrane is well suited for use in a V-RFB as a separator.