Development and characterization of Al–Ni and nanographite electrodes for energy storage

Abstract

Development new batteries is a research thrust to meet the global demand for storage energy. An aluminum (Al)-ion battery, similar to a lithium (Li)-ion battery, but with a lower manufacturing cost, was investigated, modifying the aluminum foil with nickel (Ni) coating to act as an anode, and graphite coated with nanographite powder acting as a cathode. The base electrolyte aluminum chloride (AlCl3) was modified by using additives, namely sodium chloride (NaCl), indium (III) chloride (InCl3) and mercury (II) chloride (HgCl2). The developed electrodes were electrochemically characterized by cyclic voltammetry, chronoamperometry and potentiodynamic polarization, while the constituents and morphology were examined by X-ray diffraction and electron microscopy. It was found that the nanographite powder produced a higher current density and more energy compared to the solid graphite electrode. The aluminum–nickel electrode acted as a more efficient electrode compared to the pure aluminum one, giving a much higher current during electro-oxidation. The effect of electrolyte additives such as sodium chloride, indium (III) chloride and mercury (II) chloride made the polarization resistance lower and the current higher. An electrolyte composition of 0·075 M aluminum chloride + 2 M sodium chloride + 4 M indium (III) chloride + 5 M mercury (II) chloride produced the highest current density and energy.