The use of gold impregnated carbon-polymer electrodes with the soluble lead flow battery

Abstract

The soluble lead flow battery (SLFB) is a hybrid redox flow battery. During charge, lead and lead dioxide are deposited onto the negative and positive electrode surfaces respectively from Pb2+ ions dissolved in a methanesulfonic acid electrolyte. Many of the challenges for the SLFB are related to these solid deposits, particularly the positive lead dioxide deposit. Gold has been shown to be an effective substrate for lead dioxide deposition. However, the prohibitively high cost of pure gold prevents its use as an electrode material. Therefore, using low mass loadings of gold at the surface of carbon-polymer electrodes is proposed. Gold impregnated carbon-polymer electrodes are tested in static electrolyte soluble lead cells. The addition of gold leaf onto the surface of the electrodes improved the peak energy efficiency by 5%. The cycle life of the cell was also improved from 13 cycles using plain electrodes to 29 cycles using the gold plated electrodes. The use of gold at the positive electrode appears to reduce the likelihood of failure due to shorting.