Asymmetric Performance Testing of Carbon Felt Electrodes to Identify the Limiting Electrode in Vanadium Redox Flow Battery

In this study, the performance of a vanadium redox flow battery (VRFB) is measured with raw and heat-treated electrodes using symmetric (i.e., same electrode used in both half-cell) and asymmetric electrode configuration (i.e., different electrodes used in positive and negative half-cells). The goal with these tests is to determine the effects of the surface functionalization on the half-cell reactions and identify the half-cell that limits the performance of a VRFB. Results indicate that surface functionalization has a minimal impact on the reaction kinetics at the positive half-cell; however it substantially affects the reaction kinetics of the negative half-cell, suggesting that the negative half-cell electrode may limit the performance of these systems.