A novel ionic liquid for improvement of lead-acid battery performance and protection of its electrodes against corrosion

A novel ionic liquid (IL) (1-octyl-3-propyl-1H-imidazole-3-ium iodide) was synthesized and used as a corrosion inhibitor for battery electrodes in 34% H2SO4 solution because IL compounds have high ionic conductivity and superior adsorption capabilities. Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy were used to identify the novel IL. According to electrochemical measure-ments, IL molecules adsorption on the electrode surface of the battery increased the charge transfer resistance, which in turn enhanced the inhibition efficiency, which reached 91.64% in the electrochemical impedance spectroscopy (EIS) and 87.70% in the electrochemical frequency modulation (EFM) technique. The adsorption of IL molecules on the surface of the battery electrode is demonstrated by several surface morphology in-vestigations. The battery tests were performed using Pb-Ca alloy as the working electrode. Results of the tests indicated an increase in both electrical capacity efficiencies from 84.66 to 97% and reserve capacity from 50 to 60 min. Thus, this IL compound can improve the battery performance if used as an electrolyte additive.