Resistor Design for the Use of Dynamic Hydrogen Electrode in Vanadium Redox Flow Batteries

Abstract

Vanadium redox flow batteries (VRFBs) are attracting increasing amounts of attention for energy storage applications. However, their electrochemical performance capabilities have not been closely analyzed because proper reference electrodes remain elusive. In this work, we report the resistor design of a dynamic hydrogen electrode (DHE) for VRFBs which enables the in-situ monitoring of the positive and negative electrode potential. Due to the presence of multiple redox couples at the reference electrode inserted into the VRFB membrane, the adjustment of the current flowing through the DHE with the resistor is the key factor when attempting to maintain a stable and steady hydrogen reduction reaction at the DHE during repeated charge and discharge processes. With the insertion of the DHE into the membrane, the electrochemical properties of the positive and negative electrode/electrolyte can be individually analyzed. Thus, the DHE design provides an effective electrochemical analysis platform for VRFB research. (C) 2016 Elsevier Ltd. All rights reserved