Lead acid hybrid batteries of differential ionic interfaces

Abstract

Cost-effective and energy-efficient storage system is essential for both power grid interfacing and the automotive industry. With the advantages of low maintenance, low self-discharge, and more importantly-relatively low cost of production, these easy-to-made lead acid batteries remain as one of those solutions. Two hybrid battery systems compose of lead acid and nickel metal hydride batteries are studied. Here, we introduce an alternative configuration of ionic interface that allows both acid and alkaline solutions co-existing in a single hybrid battery system. Each hybrid cells have a positive PbO2 electrode and a negative MH electrode suspended in H2SO4 and KOH respectively. The acidic and alkaline compartments are separated by either a bipolar membrane (Dual electrolyte system), or two ion exchange membranes (a pair of cation exchange membrane and anion exchange membrane) with a neutral K2SO4 solution in between (Three-electrolyte system, See Fig. 1). The electrochemical performance of both dual electrolyte and three-electrolyte systems are reported …