Al-air Battery Research Articles

Improvement of Electrochemical Performance with Cetylpyridinium Chloride for the Al Anode of Alkaline Al-Air Batteries

Improvement of Electrochemical Performance with Cetylpyridinium Chloride for the Al Anode of Alkaline Al-Air Batteries

Atomically modulated Cu single-atom catalysts for oxygen reduction reactions towards high-power density Zn- and Al-air batteries.

Herein, Cu single-atom-encapsulated hollow carbon-nitrogen spheres (CuSA@CNS) are fabricated through a solution process, confining optimal electronic structures reinforcing Cu-N4 active sites. CuSA@CNS demonstrate a remarkable half-wave potential of 0.95 V, mass activity, and a durability of 5000 cycles. Accordingly, CuSA@CNS present record-high power densities of 371 and 289 mW cm-2 for Zn- and Al-air batteries. The rechargeable Zn-air battery demonstrates an unprecedented small charge-discharge voltage and stable cycling for harsh operations at 50 mA cm-2, outperforming Pt/C.

Corrosion Inhibition of PAAS/ZnO Complex Additive in Alkaline Al-Air Battery with SLM-Manufactured Anode

In order to improve the electrochemical activity and discharge performance of aluminum–air batteries and to reduce self-corrosion of the anode, an SLM-manufactured aluminum alloy was employed as the anode of the Al-air battery, and the influence of PAAS and ZnO inhibitors taken separately or together on the self-corrosion rate and discharge performance of the Al-air battery in a 4 M NaOH solution were investigated. The experimental result indicated that the effect of a composite corrosion inhibitor was stronger than that of a single corrosion inhibitor. The addition of the compound inhibitor not only promoted the activation of the anode but also formed a more stable composite protective film on the surface of the anode, which effectively slowed down the self-corrosion and improved the utilization rate of the anode. In NaOH/PAAS/ZnO electrolytes, the dissolution of the Al6061 alloy was mainly controlled by the diffusion of the electric charge in the corrosion products or the zinc salt deposition layer. Meanwhile, for the Al-air battery, the discharge voltage, specific capacity, and specific energy increased by 21.74%, 26.72%, and 54.20%, respectively. In addition, the inhibition mechanism of the composite corrosion inhibitor was also expounded. The excellent discharge performance was due to the addition of the composite corrosion inhibitor, which promoted the charge transfer of the anode reaction, improved the anode’s activity, and promoted the uniform corrosion of the anode. This study provides ideas for the application of aluminum–air batteries in the field of new energy.

Electrohydrodynamic Printing Grid-Structured Catalytic Layers with Excellent Bending Resistance for Flexible Al-air Batteries.

The catalytic film of a flexible Al-air battery is generally a brittle film formed by brushing a slurry onto the surface of carbon cloth. Fatigue bending can easily lead to cracking of the catalytic film and shedding of the active material. This study innovatively proposes a novel grid-structured catalytic layer prepared by electrohydrodynamic printing. Experiments have verified that, compared with traditional catalytic films, the grid-structured catalytic layer exhibits excellent bending resistance. After 10 000 fatigue bending cycles, its relative resistance is ≈1/9 that of the traditional catalytic film. The printed grid-structured catalytic layer is applied to a flexible Al-air battery, which maintains a power density retention rate as high as 92% after the same number of bending cycles. Compared to traditional catalytic films, the electrodynamically printed grid-structured catalytic layer proposed in this study demonstrates both excellent electrochemical performance and bending resistance. This advancement holds significant importance for the development and application of flexible metal-air batteries.

Nickel-Nitrogen Doped MnO2 as Oxygen Reduction Reaction Catalyst for Aluminum Air Batteries.

Aluminum-air battery has the advantages of high energy density, low cost and environmental protection, and is considered as an ideal next-generation energy storage conversion system. However, the slow oxygen reduction reaction (ORR) in air cathode leads to its unsatisfactory performance. Here, we report an electrode made of N and Ni co-doped MnO2 nanotubes. In alkaline solution, Ni/N-MnO2 has higher oxygen reduction activity than undoped MnO2, with an initial potential of 1.00 V and a half-wave potential of 0.75 V. This is because it has abundant defects, high specific surface area and sufficient Mn3+ active sites, which promote the transfer of electrons and oxygen-containing intermediates. Density functional theory (DFT) calculations show that MnO2 doped with N and Ni atoms reduces the reaction overpotential and improves the ORR kinetics. The peak power density and energy density of the Ni/N-MnO2 air electrode increased by 34.03 mW cm-2 and 316.41 mWh g-1, respectively. The results show that N and Ni co-doped MnO2 nanotubes are a promising air electrode, which can provide some ideas for the research of aluminum-air batteries.

Regulating the Helmholtz plane by trace ionic liquid additive for advanced Al-air battery

Al-air batteries (AABs) are the next generation of alternative energy sources due to their high theoretical energy density, low cost, and environmental friendliness. Researchers have been interested in AABs with stable discharge in alkaline solution, long discharge time, and high conductivity. However, the uncontrolled self-corrosion of the Al anode and the severe hydrogen evolution reaction in alkaline electrolytes have been two major drawbacks hindering the commercial development of AABs. These shortcomings reduce the Al anode's utilization and significantly shorten the battery's service life. Herein, the Helmholtz plane structure was reconstructed using an ionic liquid additive called 1-aminopropyl-3-methylimidazolium bromide (AMIB) to regulate the electrochemical interface between the electrolyte and the Al anode. Electrochemical tests found that when 3 mM AMIB was added, the corrosion inhibition efficiency could reach up to 60 %. Further surface analysis and theoretical calculations showed that AMIB can form a dense and uniform protective layer on the surface of the Al anode substrate, which reduces the anode corrosion, lowers the active centers for hydrogen evolution on the Al surface, and reduces the hydrogen evolution rate. The full-cell studies found that the specific capacity of the cell increased from 1227 to 2564 mAh g−1, the energy density increased from 1546 to 3359 Wh kg−1, and the Al anode utilization increased from 41.2 % to 86.1 % as the AMIB addition to the alkaline electrolyte risen from 0 to 3 mM. This method of electrolyte regulation provides an efficient strategy for the commercial development of AABs.

Recycling of spent heat pack towards Fe-Fe3O4@NC catalyst for ORR in direct methanol fuel cells and Al-air batteries

The effective repurposing of waste materials is crucial for sustainable development. The widespread use of disposable iron-based chemical warmers (IBCW) generates substantial solid waste annually. In this study, IBCWs were repurposed as raw materials to synthesize different electrocatalyst composites comprising metallic and oxide forms of iron embedded in nitrogen-doped carbon (NC). The composites were evaluated as oxygen reduction reaction (ORR) catalysts. The optimized Fe-Fe3O4@NC demonstrated enhanced ORR kinetics, with an onset potential of 0.92 V and a half-wave potential of 0.86 V vs. RHE. As an air cathode for direct methanol fuel cell (DMFC), Fe-Fe3O4@NC achieved a power density of 33.3 mW cm−2 at 88 mA cm−2, demonstrating its practical applicability. Additionally, a quasi solid-state aluminium-air battery (SAAB) was assembled using this catalyst as the air cathode with a PVA-KOH gel electrolyte and the separator. The quasi SAAB exhibited an open circuit voltage (OCV) of 1.46 V, a power density of 40 mW cm-2, and good rate capability compared to Pt/C. The combined effect of metallic and oxide iron with nitrogen doping enhances the overall catalytic activity. This study demonstrates that IBCWs can be effectively transformed into valuable catalysts for renewable energy applications, enabling clean and sustainable utilization of waste materials.

Mitigating anodic corrosion in aluminum–air batteries: Effects of alkali metal cation size on electrochemical performance

Anodic corrosion limits the performance of aluminum–air batteries (AABs) by reducing discharge capacity and hindering energy density. This study proposes a strategy to mitigate anodic corrosion by controlling electrolyte cations to decrease the activity of free water molecules in the anodic corrosion process. Alkali metal cations (Na+, K+, Rb+) are introduced into a 1mol dm−3 KOH solution to examine their solvation properties and effects on free water molecule activity. Results show that larger cations (Na+ < K+ < Rb+) enhance anode discharge capacity by promoting more stable discharge reactions. Raman spectroscopy reveals that as cation radius increases, free water molecule activity decreases due to increased hydration. X-ray photoelectron spectroscopy analysis shows that larger cations favor the formation of corrosion-resistant aluminum compounds like Al2O3 and Al(OH)3, due to their higher concentration in the electric double layer, inhibiting anodic corrosion. This study highlights the critical role of cation solvation in enhancing electrochemical performance and corrosion resistance of AAB anodes.

Recent progress in inhibition of hydrogen evolution reaction in alkaline Al-air batteries

Recent progress in inhibition of hydrogen evolution reaction in alkaline Al-air batteries

Oxophilic Low‐Coordination Gd‐N3 Single Atom Sites With P‐Enhanced Second Coordination for High‐Performance Al‐Air Batteries

AbstractThe development of efficient rare earth single‐atom (SA) catalysts for the oxygen reduction reaction (ORR) is essential yet challenging for high‐performance aluminum‐air batteries (AABs). This study introduces a concept‐to‐proof strategy for synthesizing a hollow carbon‐supported gadolinium (Gd) SA catalyst using low‐coordination and second‐coordination sphere engineering. In this design, Gd atoms are coordinated to three nitrogen (N) atoms in N‐doped carbon and surrounded by six phosphorus (P) atoms, forming Gd‐N3‐P6 sites. These catalysts demonstrated exceptional ORR performance, achieving a half‐wave potential of 0.895 V and superior durability compared to the commercial Pt/C benchmark. When integrated into AABs, they delivered impressive performance, with a peak power density of 257 mW/cm2 and an energy density of 2916 Wh/kg, alongside enhanced cycling stability. In situ characterization and theoretical calculations revealed that the strategic placement of P atoms in the second coordination sphere significantly enhanced the valence state of the Gd site. This enhancement improved the adsorption capacity for O2 and H2O while facilitating the rapid desorption of *OH intermediates during the ORR. This study offers valuable insights into the development of cost‐effective ORR catalysts, emphasizing the significance of modulating the local coordination environment of metal SA sites.

Three-center-four-electron hydrogen bond bridged by fluorine enables advanced electrolyte for aluminum air batteries

Aluminum air batteries have great potential as a state-of-the-art energy storage device due to their high capacity, energy density and fascinating safety. However, the disturbing hydrogen evolution reaction (HER) of the Al anode increase the gap between practical application and theoretical level. Electrolyte engineering with organic additives has been the spotlight to address the problem of HER. The polar functional group of organic molecules could bound with the water via the hydrogen bond to drop the activity of water. Unfortunately, the basic physicochemical properties of electrolyte would be deteriorated due to the organic matter, which has a negative impact on the electrochemical performance of batteries. Herein, an inorganic additive was adopted to regulate the hydrogen bond network and anode interface. The activity of H2O could be obviously suppressed by the stronger three-center-four-electron hydrogen bonds bridged by fluoride ions. And the water molecules are kept away from the anode surface due to the protective layer caused by the adsorption of fluoride ions. The HER could be greatly inhibited by both pathways, which reaches an inhibition efficiency of 55% in the electrolyte with 5 M KF. Correspondingly, the Al air battery exhibits a high discharge specific capacity of 1552.8 mAh g−1 and an energy density of 1829.51 Wh kg−1 at a current density of 25 mA cm−2. This work showcases a promising inorganic additive to suppress the HER for high-performance Al air battery.

Modulation of Al-Zn-0.5Sn-0.5Mn anode properties by trace Sb

In aluminum-air batteries, hydrogen precipitation corrosion is a difficult problem for aluminum anodes in alkaline electrolytes, which causes a decrease in the efficiency and shortens the service life of aluminum anodes. Under the condition of 4 mol·L-1 NaOH alkaline solution, the addition of trace Sb (0.04 wt%) to Al-Zn-0.5Sn-0.5Mn resulted in an increase of 88.64% in energy density and 74.03% in the specific capacity of the aluminum anode, and a constant current discharge at a current density of 10 mA·cm-2, with a discharge voltage as high as 1.43 V and the discharge process is stable, the anode efficiency reaches 90.90% and the energy density reaches 2526 Wh·kg-1. The improvement in the performance of the aluminum anode is mainly due to the precipitation of the AlSb phase, which activates the grain boundaries, improves the electrochemical activity of the aluminum anode, and forms Sb-containing membranes to inhibit the formation of surface passivation films. Efficient discharge in alkaline solution and long battery life.

The Effect of Hatch Spacing on the Electrochemistry and Discharge Performance of a CeO2/Al6061 Anode for an Al-Air Battery via Selective Laser Melting

To improve the electrochemical activity and discharge performance of an aluminum-air (Al-air) battery, a commercial 6061 alloy (Al6061) was selected as the anode, and CeO2 was also added inside the anode to enhance its performance. The CeO2/Al6061 composite was prepared using selective laser melting (SLM) technology. The influence of hatch spacing on the forming quality, corrosion resistance, and discharge performance of the anode was studied in detail. The results showed that with an increase in hatch spacing, the density, corrosion resistance, and discharge performance of the anode first increased and then decreased. When the hatch spacing is 0.13 mm, the anode has the best forming quality. At this point, the density reaches 98.39%, and the self-corrosion rate (SCR) decreases to 2.596 × 10−4 g·cm−2·min−1. Meanwhile, the anode exhibits its highest electrochemical activity and discharge voltage, which is up to −1.570 V. The change in anode performance is related to the defects generated during the SLM forming process. For samples with fewer defects, the anode can dissolve uniformly, while for samples with more defects, the electrode solution is prone to penetrate the defects, causing uneven corrosion and reducing electrochemical and discharge activity.

Regulating H-bonded network of aqueous electrolytes for stable and energy-dense Al-air batteries

Aluminum-air batteries offer unique advantages over other aqueous batteries in terms of environmental friendliness, energy density, resource abundance, and cost-effectiveness. Nevertheless, the parasitic hydrogen evolution reaction (HER) of anode presents severe challenges for stable and long-term operation of batteries. Here we found that the mixed solution with strong H-bond network has a significant inhibitory effect on the self-discharge and HER of Al anode in alkaline electrolyte. And establishing the relationship between the molecular structure of the cosolvent (carbon chain lengths and hydrogen bond acceptors) and the strength of the hydrogen bonding network of the electrolyte. The as-constructed Al-air battery with ethylene glycol (EG) cosolvent demonstrates a remarkable increased discharge specific capacity of 2725 mAh g-1, corresponding to the Al anode utilization of 91.4 %. The operation time also extends to 160 h at 5 mA cm-2. This work provides new avenues to understand the role of H2O in aqueous electrolytes and explore low-cost and effective approaches for the development of next-generation aqueous Al-air batteries.

Interfacial activation of anode in aluminum-air battery through incorporating 5-carboxyl benzotriazole@β-cyclodextrin assembly in synthetic seawater electrolyte

Neutral electrolyte, such as synthetic seawater (SW), is a promising candidate for aluminum-air (Al-air) battery due to the alleviated hydrogen evolution along with anode self-corrosion. However, aluminum surface passivation in SW poses a serious challenge for battery's power generation. Following molecular self-assembly theory, 5-carboxylate benzotriazole (CB) was incorporated into β-cyclodextrin (β-CD), which (CB@β-CD) was utilized as an interfacial activator for aluminum anode in SW. CB could be released from β-CD, and activated aluminum surface, facilitating anode discharge. The specific capacity and energy density of Al-air battery were achieved as 2607.4 mAh/gAl and 2.37 kWh/kgAl, respectively, at an optimal CB@β-CD concentration of 120 mg/L. Density functional theory calculations revealed that the overwhelming adsorption energy of guest molecule (CB) on Al (111) plane over its binding energy inside host (β-CD) accounted for the release of CB on anode surface, and the ensuing interfacial activation effect.

Multi-Objective Optimization for the Forming Quality of a CeO2/Al6061 Alloy as an Aluminum–Air Battery Anode Manufactured via Selective Laser Melting

To improve the discharge performance of aluminum–air batteries, CeO2/Al6061 composites were prepared as an anode using selective laser melting (SLM). Response surface methodology (RSM) was employed, and the test results were linearly fitted. A prediction model for the forming quality of the composite anode was established, and the reliability of the model and the interaction between process parameters were explored based on variance analysis and significance testing. On this basis, with corrosion potential, self-corrosion rate, and discharge voltage as optimization objectives, the optimal solution set of the SLM forming CeO2/Al6061 anode process parameter was solved through a genetic algorithm, and experimental verification was conducted. The results indicate that the optimal process range for the forming quality and various properties of composite materials is laser power of 265~285 W, scanning speed of 985~1025 mm/s, and scanning spacing of 0.116~0.140 mm. The optimized process parameters were selected for reliability testing, and the errors were all within 3.0%, verifying the accuracy and reliability of the model.

Beyond Barrier Function: Exploring the Potential of Polymer Coatings for High-Performance Aluminum–Air Batteries

Beyond Barrier Function: Exploring the Potential of Polymer Coatings for High-Performance Aluminum–Air Batteries

Building aluminium-air battery on waste paper for DIY learning

Abstract Environmental sustainability and the effective use of renewable resources are critical subjects that need to be integrated into our educational systems through practical, hands-on learning. This paper focuses on the fabrication of aluminium-air batteries using waste materials, providing an innovative and cost-effective DIY approach to energy storage education. Utilizing aluminium from food packaging and graphite from pencils, this study demonstrates the construction and functionality of an aluminium-air battery to run an LED, highlighting its potential applications in educational settings and low-cost energy solutions. The paper aims to inspire the adoption of environmentally friendly practices and enhance students’ understanding of electrochemical energy conversion through accessible and engaging DIY projects.

The effect of Artemisia capillaris leaf extract as a benign corrosion inhibitor on the performance of Al–air batteries

The self-corrosion of the aluminum anode reduces largely the performance of Al-air batteries. Herein, we report on the effect of Artemisia capillaris leaf extract (ACLE) as a benign corrosion inhibitor on the performance of Al-air batteries in 4 M NaOH electrolyte. The hydrogen evolution tests, electrochemical measurements, and surface analysis show that ACLE can markedly reduce the corrosion current density of the Al electrode in 4 M NaOH, which is due to the adsorption of the active components in ACLE inhibitor on the Al electrode surface. The presence of ACLE in 4 M NaOH greatly reduces the self-corrosion of the Al anode, and thus improves the utilization rate of the Al electrode. Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) are employed to determine the chemical composition of the adsorption layers on the surface of the Al electrode. When the concentration of ACLE in 4 M NaOH is 5 g/L, the Al-air battery has a high practical capacity density of 3545 Wh kg−1, and the fuel efficiency also increases to a high value of 44 % from 14 % without ACLE. This work presents a novel approach to enhance the performance of Al-air batteries through the utilization of natural product extracts as corrosion inhibitors.

Inhibited Passivation by Bioinspired Cell Membrane Zn Interface for Zn-Air Batteries with Extended Temperature Adaptability.

Due to the slow dynamics of mass and charge transfer at Zn|electrolyte interface, the stable operation of Zn-air batteries (ZABs) is challenging, especially at low temperature. Herein, inspired by cell membrane, a hydrophilic-hydrophobic dual modulated Zn|electrolyte interface is constructed. This amphiphilic design enables the quasi-solid-state (QSS) ZABs to display a long-term cyclability of 180 h@50mAcm-2 at 25°C. Moreover, a record-long time of 173 h@4mAcm-2 at -60°C is also achieved, which is almost threefolds of untreated QSS ZABs. Control experiments and (in situ) characterization reveal that the growth of insulating ZnO passivation layers is largely inhibited by tuned hydrophilic-hydrophobic behavior. Thus, the enhanced transfer dynamic of Zn2+ at Zn|electrolyte interface from 25 to -60°C is attained. As an extension, the QSS Al-air batteries (AABs) with bioinspired interface also show unprecedented discharge stability of 420 h@1mAcm-2 at -40°C, which is about two times of untreated QSS AABs. This bioinspired-hydrophilic-hydrophobic dual modulation strategy may provide a reference for energy transform and storage devices with broad temperature adaptability.