Performance Improvement of Alkaline–Electrolyte Aluminum–Air Batteries by NH₄VO₃-Based Additives

Abstract

Due to their high theoretical volumetric capacity, aluminum–air batteries are an up-and-coming alternative for energy storage in mobile applications. However, there are still several problems that need to be solved to make the technology commercially viable. One of the most significant problems in this type of battery is self-corrosion in alkaline electrolytes. For that reason, in this study, we implemented NH4VO3 and NH4VO3 derivatives mixed with carboxymethyl cellulose (CMC) as high-performance anticorrosive additives in cells that contain commercial aluminum alloys (Al7475, Al6062, and Al5052) as anode and alkaline liquid or gelled electrolytes. We compared these batteries with blank batteries (no additive) and batteries that contain the most studied ZnO additive. We observed that cells with NH4VO3 additives outperformed blank cells or cells with ZnO additives in terms of specific capacity and energy. Notably, in the case of cells with liquid electrolytes, NH4VO3 and NH4VO3 + CMC additives also duplicated the battery’s performance time. We also implemented NH4VO3-based additives in four-battery-stack configurations connected in series and concluded that these additives are promising candidates for aluminum–air cells.

Aluminum–air batteries: current advances and promises with future directions

“…[106][107][108] Besides, the electrolytes employed in these batteries are generally in liquid or semi-solid from, which can be ionic, aqueous, or polymer-gel. [109][110][111] The detailed description studies related to these components are discussed in the later sections/ sub-sections. Here, in the following sub-sections, the electrochemical behavior and related reactions are explained to understand the mechanism of the Al-air battery.…”

“…The composition and concentration of the electrolyte can inuence the electrochemical reaction rate on both sides of the electrodes. 92,110 The composition of the electrolyte affects the formation and passivation layers on the aluminum anode surface. Thus, an appropriate electrolyte formulation and its optimization for a given solvent can help prevent excessive passivation, ensuring continuous electrochemical activity throughout the operation together with an optimal battery capacity and energy density.…”

Benchmarking of Aluminum Alloys Processed by High-Pressure Torsion: Al-3% Mg Alloy for High-Energy Density Al–Air Batteries

“…The low performance of the anodes due to corrosion by hydrogen formation can be solved with the addition of corrosion inhibitors to the electrolyte, such as zinc oxide, − vanadate salts, , dicarboxylic acids, and hydroxyquinoline to reduce the rate of self-corrosion. Xu et al .…”

Synergistic Effect of Vanadate and Nanoclay Hybrid Inhibitor on the Self-Corrosion and Discharge Activity of Al Anode in Alkaline Aluminum-Air Batteries

“…One of them is creating new alloys with various alloying components, such as Zn, Sn, Ga, In, and Ca, which is considered a costly method. 9 The positive shift in the anode potential and enhancement of the HER overpotential, both possible with In and Sn is associated with faster rates of Al dissolution in aqueous solutions and slower rates of corrosion. 10 Studies have demonstrated that zinc (Zn) increases the HER's overpotential, which suppresses the HER.…”

“…In this regard, various mixtures, including ZnO/cetyltrimethylammonium bromide (CTAB) and ZnO/carboxymethyl cellulose (CMC) have been examined, demonstrating a more uniform layer, a higher discharge capacity, and a delay in the self-corrosion reaction of Al. 9,13,14 The ability of batteries to discharge should not be compromised by limiting the self-corrosion process of Al-based anodes. 15 In corrosive conditions like salt water, some inorganic salts are the first corrosion inhibitors utilized for Al alloys.…”