Improving the performance of lead acid batteries

In this study, fumed silica-based gel electrolyte systems were prepared for lead-acid batteries and charge-discharge tests were performed to investigate the performance of these gel systems. In this context, primarily the concentration of acid used to prepare the gel systems and scanning rate for the cyclic voltammetry were determined as w/w % 30 and 20 mVs-1, respectively. Later, the optimum concentration of fumed silica was determined as w/w % 6 (v/v % 66) to prepare the gel systems. The novel gel formulations were obtained adding different amounts of some additives (TiO2, B2O3, Al2O3, Na2SO4, MgSO4) into the gel system having optimum amount of fumed silica. Besides, the electrochemical behaviors of gel systems having fumed silica and TiO2 were determined in different temperatures.Electrochemical methods were used to determine the optimum concentrations, stirring time and stirring rate for the preparation of the electrolyte systems. In this perspective, cyclic voltammetry (CV) and electrochemical impedance spectroscopy methods (EIS) were performed to characterize the gel electrolyte systems as electrochemical. The performance of the gel systems was determined using the cyclic charge-discharge method. According the results of cyclic charge-discharge tests, the capacities of gel systems having fumed silica and other additives were better than the system having just sulfuric acid. The best capacity was determined the gel system having w/w % 6 fumed silica as 3,5 mAh.Finally, the surface morphology of the electrode used for cyclic voltammetry was characterized by scanning electron microscope (SEM). The gel electrolyte systems were investigated using optical microscopy.Keywords: Lead-Acid Battery, Cyclic Voltammetry (CV), Impedance Spectroscopy (EIS), Cyclic Charge-Discharge, Fumed Silica, Gel Electrolyte