Al-air Battery Research Articles

Effects of ultrasound on synthesis and performance of manganese-based/ graphene oxide oxygen reduction catalysts for aluminum-air batteries

In this research, manganese (Mn) based/graphene oxide (GO) composites, which are used as cathode catalysts for aluminum(Al)-air battery are successfully prepared via ultrasound method using KMnO4–MnSO4-GO system. The effects of ultrasonic amplitude on the synthesis and performance of catalysts are both investigated. The result reveals that changing the ultrasonic amplitude (10, 15 μm and 20 μm) is able to effectively affect the composition of catalysts, and which further influence their electrocatalytic and discharging performance. The catalyst obtained under an ultrasonic amplitude of 15 μm is composed of γ-manganese oxyhydroxide (γ-MnO(OH)), α-manganese dioxide (α-MnO2) and GO, which has good electrocatalytic performance closing to a commercial 20% Platinum (Pt)/Carbon (C) catalyst. This research proposes a novel and efficient method by using ultrasound to prepare Mn based/GO catalysts with excellent electrocatalytic performance, which exhibit great potential in the field of metal-air battaries.

Coordination strategy to prepare high-performance Fe-Nx catalysts for Al-air batteries

Coordination strategy to prepare high-performance Fe-Nx catalysts for Al-air batteries

Inhibitive effect of anionic/zwitterionic hybrid surfactants on the self-corrosion of anode for alkaline Al-air battery

Surfactants have been increasingly used as corrosion inhibitors in recent years. The zwitterionic surfactants can keep their amphoteric characteristics within a wide range of pH and temperature. In this research work，the self-corrosion of Al anode in alkaline electrolyte for Al-air battery is suppressed by adding a hybrid corrosion inhibitor consisting of dodecyl dimethyl betaine (DDBT) and sodium dodecylbenzene sulfonate (SDBS). The hybrid surfactant behaves as an anodic inhibitor. The results show that the optimum inhibition efficiency is 91.27 % for 1 × 10−3 M DDBT + 4 × 10−3 M SDBS. The combination of DDBT and SDBS decreases the corrosion rate of AA5052 alloy in sodium hydroxide electrolyte. The hydrophilic heads of DDBT and SDBS can adsorb on surface. The long alkyl chains in surfactant bring an increase in hydrophobicity. The hybrid surfactants have the electrostatic interaction and hydrophobic interaction, which improving the inhibition effect for the hydrogen evolution reaction. In general, the mixture of anionic and zwitterionic surfactants can provide the potential for better inhibition performance and significance for practical application.

Ionic conductive cellulose-based hydrogels for Al-air batteries: Influence of the charged-functional groups on the electrochemical properties

Gel electrolytes for aluminum-air (Al-air) primary batteries were prepared based on hydroxyethyl cellulose (HEC) and acrylate monomers bearing differently charged functional groups (i.e., -COOCH2CH2N+(CH3)3Cl−, -COO- and -COOCH2CF3). The acrylate monomers were grafted from HEC backbone and crosslinked using methylenebisacrylamide (MBA) to obtain hydrogels with tuned mechanical (15–75 kPa), morphological (pore size 35–125 μm) properties and varied swelling degrees at alkaline electrolyte (900–2500%). Electrochemical measurements were performed on Al-air cells assembled from Al anode, gel electrolytes (in 1 M NaOH) and carbon-based air-cathodes containing silver fine particles (Ag-FPs). Hydrogels with quaternary ammonium salt (HEC-AEtMACl) showed very long discharge time (6.5 h) compared to 1.8 h with the fluorinated hydrogels (HEC-TFEMA) and 1.1 h with carboxylated hydrogels (HEC-AA). Also, HEC-AEtMACl showed the highest current peak (3.9 μA at 1.4 V). Polarization curves proved that the anodic polarization behavior is dominant resulting from the anodic parasitic reaction. The Electrochemical Impedance Spectroscopy (EIS) evidenced that HEC-TFEMA has ionic conductivity (34.4 mScm−1) higher than that of HEC-AEtMACl. However, the highest specific capacity was observed to HEC- AEtMACl 0.928 mA h/cm2 compared to 0.26 and 0.15 mA h/cm2 for HEC-TFEMA and HEC-AA respectively.

Regulating the Anode Corrosion by a Tryptophan Derivative for Alkaline Al–Air Batteries

Screening a green corrosion inhibitor that can prevent Al anode corrosion and enhance the battery performance is highly significant for developing next-generation Al-air batteries. This work explores the non-toxic, environmentally safe, and nitrogen-rich amino acid derivative, N(α)-Boc-l-tryptophan (BCTO), as a green corrosion inhibitor for Al anodes. Our results confirm that BCTO has an excellent corrosion inhibition effect for the Al-5052 alloy in 4 M NaOH solution. An optimum inhibitor addition (2 mM) has increased the Al-air battery performance; the corrosion inhibition efficiency was 68.2%, and the anode utilization efficiency reached 92.0%. The capacity and energy density values increased from 990.10 mA h g-1 and 1317.23 W h kg-1 of the uninhibited system to 2739.70 mA h g-1 and 3723.53 W h kg-1 for the 2 mM BCTO added system. The adsorption behavior of BCTO on the Al-5052 surface was further explored by theoretical calculations. This work paves the way for constructing durable Al-air batteries through an electrolyte regulation strategy.

Effect of Sn and Zn alloying with Al on its electrochemical performance in an alkaline media containing CO2 for Al-air batteries application

Aluminum alloyed with other metals, such as Sn and Zn, was synthesized via fusion to trace the impact of alloying elements on the electrochemical characteristics of Al anodes. The corrosion inhibition and electrochemical tests were performed in a 5 M KOH medium in the absence and presence of CO2 for the Al–Sn, and Al–Zn anodes and compared to the commercial aluminum. Tafel polarization exhibited that the anodic and cathodic branches display lower current densities than Al metal in pure KOH. The steady state of the open circuit voltage (Ecorr.) for the studied alloys was shifted to a more negative magnitude than for Al. The corrosion current is sharply decreased, and potential is significantly shifted to less negative values in the presence of CO2. This is due to forming of a protective layer from the carbonate of Al, Sn, and Zn on the surface. Amazing results were obtained and discussed in the case of CO2. Electrochemical impedance spectroscopy (EIS) results exhibited that charge transfer resistance (Rct) values rise with alloying elements. The data of Tafel plots are consistent with those of EIS. The alloying of Al with Sn and Zn elements significantly affects capacitance, hydrogen evolution process suppression, and charge-discharge efficiency. This reveals that the highest potential value in the presence of CO2 in the charging process is obtained for Al–Zn alloy, while the most negative potential is obtained for Al in the discharging process with CO2. Moreover, the discharge time is higher in the alloys than in commercial Al in the absence and more in the presence of CO2. The produced alloys are thought to provide good anodes for long-life rechargeable batteries.

Graphene-loaded and Mn-doped SrCoO3 perovskite oxide as a cathode catalyst for aluminum–air battery

In this study, a SrCoO3 perovskite catalyst is prepared by sol–gel method, and modified by loading graphene and doping Mn. The effects of 20% graphene loading and 50% Mn doping on the performance of SrCoO3 perovskite as a cathode catalyst for Al–air battery are studied by morphology observation, electrochemical performance analysis, and full battery test. The results show that 20% graphene loading alone and 50% Mn doping alone do not significantly improve the oxygen reduction reaction (ORR) catalytic performance. However, 50% Mn-doped SrCoO3 perovskite exhibits a fine grain size, cubic hexagonal mixed structure, and low lattice stability. The 20% graphene-loaded SrCoO3 perovskite reduces the oxygen absorption capacity and elevates the peak potential of ORR reaction. After 20% graphene-loaded SrCo0.5Mn0.5O3 effectively improves the catalytic performance of ORR. The interfacial interaction between graphene and SrCoO3 elevates the peak potential of ORR reaction, but no interaction occurs between graphene and SrCo0.5Mn0.5O3 interface. The catalyst containing the graphene-loaded SrCo0.5Mn0.5O3 perovskite exhibits outstanding electrocatalytic ORR activity and is suitable for use as cathode catalyst in Al–air battery.

Interface engineering toward self-corrosion inhibited alkaline aluminum-air battery via optimized electrolyte system

In this manuscript, an introduced ionic liquids-ethylene glycol-KOH electrolyte system is proposed. Theoretical calculations and experiments show that ionic liquids with stronger hydrophobicity provide better corrosion inhibition for their spontaneous adsorption behavior and water molecule segregation. In this process, the imidazole ring cations play a major role. The electrolyte system reconstructs the Al/electrolyte interface with poor H2O, thus has lower self-corrosion rate for [BMIM]PF6 and contributes to the uniform dissolution of Al anode. Additionally, discharge performance of the full-cell feature same trend, endowing an outstanding capacity of 1971 mAh g−1 and anode utilization of 66.2% in alkaline [BMIM]PF6-ethylene glycol electrolyte. In terms of maintaining the activity of the Al-6061 anode whilst keeping low corrosion rate level, the proposed electrolyte system seems to be potential alternative.

Investigation of the AlB2 intermetallic phases effect on Al–Zn–B alloys’ electrochemical performance in Al–air battery anodes

Investigation of the AlB2 intermetallic phases effect on Al–Zn–B alloys’ electrochemical performance in Al–air battery anodes

A Mechanistic Overview of the Current Status and Future Challenges in Air Cathode for Aluminum Air Batteries.

Aluminum air batteries (AABs) are a desirable option for portable electronic devices and electric vehicles (EVs) due to their high theoretical energy density (8100 Wh K-1 ), low cost, and high safety compared to state-of-the-art lithium-ion batteries (LIBs). However, numerous unresolved technological and scientific issues are preventing AABs from expanding further. One of the key issues is the catalytic reaction kinetics of the air cathode as the fuel (oxygen) for AAB is reduced there. Additionally, the performance and price of an AAB are directly influenced by an air electrode integrated with an oxygen electrocatalyst, which is thought to be the most crucial element. In this study, we covered the oxygen chemistry of the air cathode as well as a brief discussion of the mechanistic insights of active catalysts and how they catalyze and enhance oxygen chemistry reactions. There is also extensive discussion of research into electrocatalytic materials that outperform Pt/C such as nonprecious metal catalysts, metal oxide, perovskites, metal-organic framework, carbonaceous materials, and their composites. Finally, we provide an overview of the present state, and possible future direction for air cathodes in AABs.

Influence of an imidazole-based ionic liquid as electrolyte additive on the performance of alkaline Al-air battery

Influence of an imidazole-based ionic liquid as electrolyte additive on the performance of alkaline Al-air battery

Corrosion inhibition of L-tryptophan on Al-5052 anode for Al-air battery with alkaline electrolyte

Corrosion inhibition of L-tryptophan on Al-5052 anode for Al-air battery with alkaline electrolyte

Enhanced electrochemical performance of low-pressure-plasma-treated paper-based fluidic aluminum-air battery

This study investigates the effect of low-pressure plasma (LPP) processing of a graphite foil as the cathode of a paper-based fluidic Al-air battery. A 10-s plasma treated battery exhibited better discharge performance in terms of the current density, power density, and energy density compared with an untreated battery. Scanning electron microscopy, x-ray photoelectron spectroscopy, and water contact angle measurements were used to investigate the difference in the surface properties of the graphite foil before and after LPP modification. Further, linear sweep voltammetry, constant current discharge measurement, and electrochemical impedance spectroscopy analysis were used to demonstrate the enhancement in discharge performance.

Hydrogen-bonds reconstructing electrolyte enabling low-temperature aluminum-air batteries

Aqueous aluminum-air batteries are promising candidates for the next generation of energy storage/conversion systems with high safety and low cost. However, the inevitable hydrogen evolution reaction on the metal aluminum anode and the freeze of aqueous electrolytes hinder the practical application of aluminum-air batteries at both room temperatures and subzero temperatures. Herein, we report a hydrogen-bonds reconstructing electrolyte strategy to boost aluminum-air batteries through the dipole of glycerol molecule, thus suppressing the self-corrosion of aluminum anode and lowering down the freezing point of electrolyte. This glycerol-based electrolyte endows a flow aluminum-air full battery with an outstanding specific capacity of 1886 mAh g−1 and a low operating temperature of −60 °C. This finding provides a synthetic design strategy to mitigate metal corrosion and expand the application range of temperature adaptation of aqueous batteries.

Synergistic Reductive Electrolysis Mixture Additive-Based Dual-Cell Configuration: An Effective Approach for High-Performance Aqueous Aluminum–Air Battery

Neutral aqueous electrolyte-based aluminum–air (Al–air) batteries have managed to gather significant attention because of their characteristic safety and cost effectiveness. However, the formation of the passivation layer [Al(OH)3] on the aluminum anode inhibits the long-term shelf life of the battery. Herein, a novel strategy to overturn the passivation by altering the aluminum/electrolyte interface is proposed. Incorporation of synergistic reductive electrolysis mixture additives (Tiron + NaNO3) can significantly reduce the passivation of the aluminum anode. The efficacy of the Tiron + NaNO3 synergistic mixture additive has been systematically examined using half-cell and full-cell with different concentrations of the additives in 0.5% NaCl. Furthermore, dual cell performance was investigated with optimum concentration (0.005 M Tiron + 0.005 M NaNO3) of the additive in 0.5% NaCl as the anolyte and different concentrations of H2SO4 as the catholyte. It is found that the resulting pumpless dual cell battery comprising neutral electrolyte with 0.005 M Tiron + 0.005 M NaNO3 mixture additive as the anolyte and 1 M H2SO4 as the catholyte demonstrated a remarkable cell potential of 1.14 V at a current density of 1 mA g–1, which is closer to the theoretical value. Morphological investigations using optical microscopy studies and X-ray photoelectron spectroscopic investigations also confirmed that the Tiron + NaNO3 additive is effective in preventing the discharge product on both anode and cathode surfaces and thus resulting in enhanced battery performance.

Potent Charge‐Trapping for Boosted Electrocatalytic Oxygen Reduction

AbstractMetal‐free carbon‐based materials are considered to be one of the most promising alternatives to precious metal Pt‐based electrocatalysts. However, the electrocatalytic activity of heteroatom‐modulated carbon rarely reaches the level of metal‐based electrocatalysts. Here, electron‐rich carbon and abundant pyridinic‐N adjacent to C vacancies decorated with carbon nanosheets (E‐NC‐V) are synthesized and used as the host for boosting efficient oxygen reduction reaction. Rich pyridinic‐N structures adjacent to C vacancies work in synergy with electron‐rich carbon, which promotes the sharp decrease of |ΔGO*|, resulting in the balanced adsorption and dissociation of oxygen intermediates, and thus activating OO. This can be attributed to the abundant vacancies and d–p orbital hybridization between Zn and N/C. The E‐NC‐V catalyst drives the oxygen reduction reaction (ORR) via a 4e− transfer‐dominated pathway with a half‐wave potential of 0.87 V versus RHE in the alkaline solution, even superior to Pt/C. The assembled Al–air battery exhibits a high peak power density of 113 mW cm−2. This promising strategy sheds light on the design and fabrication of robust, rich‐density, and high‐performance active sites for the ORR. The work is expected to inspire future work on the role of electronic structure modulation and defect engineering for enhanced reaction kinetics.

Negative surface charge-mediated Fe Quantum dots with N-doped graphene/Ti3C2Tx MXene as chlorine-resistance electrocatalysts for high performance seawater-based Al-air batteries

Compared to conventional alkaline Aluminum-air (Al - air) batteries, seawater-based Al-air batteries are promising large-scale energy storage devices and are highly compatible with offshore ocean locations or large-scale maritime applications. However, the complexity of the seawater components, in particular, chlorine anions (Cl−) blocks the metal surface and hinders the oxygen reduction reaction (ORR) at the cathode. Herein, we employed plasma engineering to anchor Fe Quantum dots (QDs) on a negative charge-mediated surface composed of nitrogen-doped graphene (NG) and Ti3C2Tx MXene. The negative fluorine and hydroxyl groups on MXene and NG induced strong negative-charged surface with a build-in electric field to repel Cl−, effectively protected the Fe QDs active sites from the seawater electrolyte. As a result, the cathode electrocatalysts demonstrated high ORR catalytic activity in seawater electrolytes and achieved a high-power density output of 53.6 mW/cm2 and rate performance of 0.8 V at 50 mA/cm2 in Al-air seawater batteries.

High-performance flexible Al-air batteries with liquid alloy-activated anode

A high-performance flexible Al-air battery with liquid alloy-activated anode system is developed for wearable electronics. By constructing activation interface composed of Ga–In liquid particles (GILPs) on the Al anode, the electrochemical performance of the flexible Al-air battery is enhanced. This work validated that GILPs can not only serve as active sites for the oxidation reaction of Al atoms to avoid the generation of passivation film, but also can further expand the active Al range and improve overall performance of the battery. These GILPs also exhibit satisfying electrical conductivity to reduce the mechanical loss of the Al anode during discharge, resulting in a high energy utilization of the battery. The Al-air battery with 150 μg cm−2 GILPs displays remarkable capacities of 2345 mA h g−1 at the current density of 1 mA cm−2, 1.6 times higher than that of Al-air battery without GILPs loading. Amplification experiment of Al anodes’ thickness and area are performed. The results indicate that the lifetime of battery can be extended by scaling up thickness of Al anode, and overall battery amplification efficiency is greater than 93.5%. This study opens up a prospect for the application of Al-air batteries in the field of flexible wearable power supply devices.

Effect of cetyl trimethyl ammonium bromide as an electrolyte additive on secondary discharge performance of aluminum-air battery

Effect of cetyl trimethyl ammonium bromide as an electrolyte additive on secondary discharge performance of aluminum-air battery

Precipitation-free aluminum-air batteries with high capacity and durable service life

Aluminum-air batteries are potential candidates for future large-scale energy storage/conversion due to their high safety and energy density. However, aluminum-air batteries face the challenges of continuously accumulated discharge by-products and undesired parasitic hydrogen evolution reaction (HER), which induce inferior performance and service life. Here, HER-suppressing and precipitation-free molecular crowding electrolytes are developed using sodium polyacrylate (PANa) as the crowding agent by taking advantage of its molecular crowding effect and scale inhibition property. The introduced PANa reconfigures the hydrogen-bond networks of electrolyte to suppress the HER by molecular crowding effect. A more uniform electric field distribution can be found on the surface of aluminum anode in the electrolyte containing PANa by employing Comsol multiphysics simulation. In addition, the anion long chains of PANa are electrostatically adsorbed on the surface of Al(OH)3 by-products micro-crystal, resulting in the same negative charge on the surface of the micro-crystal to prevent further aggregation and precipitation. The fabricated flow-based aluminum-air battery exhibits an outstanding specific capacity of 2096 mAh g−1, demonstrating the remarkable positive effect of PANa-based molecular crowding electrolyte in aluminum-air batteries. This work provides new light on aqueous electrolyte design for high capacity and precipitation-free aluminum-air batteries.