Evaluation of an Alkaline Electrolyte System for Al-Air Battery

Abstract

The performance of Al-air batteries in 4 M NaOH containing ZnO or ZnO/cetyl trimethyl ammonium bromide (CTAB) hybrid inhibitor is studied by constant current discharge test. The characteristics of aluminum anodes after discharge are investigated by scanning electron microscopy (SEM), and energy dispersive analysis of X-ray (EDAX). The corrosion behavior of aluminum electrodes in 4 M NaOH containing ZnO or ZnO/CTAB is studied by means of hydrogen collection and potentiodynamic polarization. SEM and EDAX results indicate that CTAB can greatly improve the deposition of zinc so that a uniform and compact zinc layer covers on the aluminum surface.Due to the low atomic mass and the negative electrode potential, aluminum potentially attracts as an outstanding anode material for Alair battery with a high theoretical energy density. 1-3 The electrolyte is one of the important components of Al-air battery. Al-air batteries in various electrolytes such as saline, alkaline, and non-aqueous have been studied by many researchers over the past few decades. 4-6 However, Al-air batteries still encounter many challenges. For instance, a protective oxide film forms spontaneously on the aluminum surface in neutral or non-aqueous electrolytes, which retards the active dissolution of aluminum anode. Additionally, severe self-corrosion of aluminum causes the fuel loss during standby in alkaline electrolytes. 7-9 So far, these problems are still not effectively resolved so that the business applications of Al-air batteries have been hindered. One effective method to mitigate the corrosion of aluminum in alkaline solutions is to add inhibitors to the electrolytes. 10-12 Many researchers found that zinc oxide can significantly inhibit the corrosion of aluminum anodes in alkaline solutions. 13 But, if the alkaline solution only contains zinc oxide inhibitor, the deposited zinc covering on the aluminum surface is loose and spongy, which means that the inhibition of the corrosion of aluminum anodes may not sustain for a long time. As a result, in order to obtain a better deposited zinc layer covering on the aluminum surface, numerous researchers tried to add another additive to improve the deposition of zinc. 14,15 Wang found that the addition of dimethyl amine epoxy propane (DE) to the zincate-containing alkaline solution can bring about a granular zinc on the aluminum surface. But Wang mainly paid attention to the electrochemical performance of aluminum anode in the alkaline solution containing ZnO/DE hybrid inhibitor but ignored the Al-air battery performance. 16 Zhu studied the influence of some surfactants on the electrochemical behavior of zinc electrodes in alkaline solution. The results revealed that the surfactant cetyl trimethyl ammonium bromide (CTAB) can bring about a significant improvement in the morphology of the deposition of zinc. 17 Besides, the addition of surfactant cetyl trimethyl ammonium bromide (CTAB) into alkaline solution can also inhibit the corrosion of aluminum anodes. 18 However, so far, the electrolyte system o...

A review of sodium chloride-based electrolytes and materials for electrochemical energy technology

“…However, the strong corrosion and hydrogen evolution of Al as an amphoteric metal in alkaline solution greatly reduces the coulombic efficiency of the anode and causes fuel loss in the open-circuit state. 137,[156][157][158] The alkaline electrolyte easily reacts with CO 2 in the air and deteriorates. 159 Despić et al took the lead in applying the NaCl-based electrolyte in the Al-air battery and foresaw two difficulties.…”

Anode Interfacial Layer Construction via Hybrid Inhibitors for High-Performance Al–Air Batteries

“…Therefore, hybrid corrosion inhibitors are put forward to overcome the problem caused by a single inorganic inhibitor. Extensive research has verified that a hybrid corrosion inhibitor could combine the advantages of organic and inorganic inhibitors, which not only provides a protective layer to reduce the active sites of self-corrosion but also stabilizes and enhances the film by the adsorption of organic inhibitors. , Studies have shown that cetyltrimethylammonium bromide and poly­(ethylene glycol) di- acid could greatly improve the deposition of metallic zinc on the Al interface to restrain self-corrosion and amend the electrochemical properties of a pure aluminum anode (99.999 and 99.9995%). , It is found that carboxymethyl cellulose and organic acids adsorbed on Zn and Al surfaces form RCOO-Al and RCOO-Zn composite protective films to improve the electrochemical performance of the AA5052 alloy and porous Al foam (95.17%) anode. , However, the reported studies mainly concentrated on the electrochemical characterization of Al anodes, and hence, there is limited understanding on the electrode/electrolyte interface.…”

“…19,20 Studies have shown that cetyltrimethylammonium bromide and poly-(ethylene glycol) di-acid could greatly improve the deposition of metallic zinc on the Al interface to restrain self-corrosion and amend the electrochemical properties of a pure aluminum anode (99.999 and 99.9995%). 21,22 It is found that carboxymethyl cellulose and organic acids adsorbed on Zn and Al surfaces form RCOO-Al and RCOO-Zn composite protective films to improve the electrochemical performance of the AA5052 alloy and porous Al foam (95.17%) anode. 23,24 However, the reported studies mainly concentrated on the electrochemical characterization of Al anodes, and hence, there is limited understanding on the electrode/electrolyte interface.…”

Experimental research on temperature rise and electric characteristics of aluminum air battery under open-circuit condition for new energy vehicle

“…At present, there are many research institutes around the world having studied the application of aluminum air batteries in various fields . However, these researches on aluminum air batteries mainly focus on the improvement of anticorrosion performance of aluminum alloy, the improvement of waterproof and gas permeability of oxygen positive electrode, the improvement of catalyst activity, the development of different types of liquid and gel electrolytes, and the improvement of various inhibitors' effects . The research on the performance parameters of aluminum air battery, such as the open‐circuit voltage (OCV), is still relatively rare.…”

“…[6][7][8][9][10][11][12] However, these researches on aluminum air batteries mainly focus on the improvement of anticorrosion performance of aluminum alloy, the improvement of waterproof and gas permeability of oxygen positive electrode, the improvement of catalyst activity, the development of different types of liquid and gel electrolytes, and the improvement of various inhibitors' effects. [13][14][15][16][17][18][19] The research on the performance parameters of aluminum air battery, such as the open-circuit voltage (OCV), is still relatively rare. The OCV is an approximation of the battery electromotive force, and in current actual test, the electromotive force is measured by the OCV value.…”