Developing Electrolyte for a Soluble Lead Redox Flow Battery by Reprocessing Spent Lead Acid Battery Electrodes

Abstract

The archival value of this paper is the investigation of novel methods to recover lead (II) ions from spent lead acid battery electrodes to be used directly as electrolyte for a soluble lead flow battery. The methods involved heating electrodes of spent lead acid batteries in methanesulfonic acid and hydrogen peroxide to dissolve solid lead and lead dioxide out of the electrode material. The processes yielded lead methanesulfonate, which is an electrolyte for the soluble lead acid battery. The lead (II) ions in the electrolyte were identified using Inductively Coupled Plasma Mass Spectroscopy and their electrochemistry confirmed using cyclic voltammetry. The concentration of lead (II) ions was determined and it was found that using the higher concentration of hydrogen peroxide yielded the highest concentration of lead (II) ions. The method was therefore found to be sufficient to make electrolyte for a soluble lead cell.