Mg-air Battery Research Articles

Prussian Blue Analogue Derived Co3O4/CuO Nanoparticles as Effective Oxygen Reduction Reaction Catalyst for Magnesium-Air Battery

Developing efficient, durable, and cost-effective non-noble metal catalysts for oxygen reduction reaction (ORR) is necessary to promote the efficiency and performance of Mg-air batteries. Herein, the Co3O4/CuO nanoparticles were synthesized by a low-cost and simple approach using CuCo-based prussian blue analogue (PBA) as precursor of pyrolysis at different calcination temperatures. It was found that the Co3O4/CuO nanoparticles calcined at 600 °C (CCO-600) have relatively small size and superior ORR performance. The onset potential is 0.889 V and the diffusion limiting current density achieves 6.746 mA·cm−2, as well as prominent stability in 0.1 M KOH electrolyte. The electron transfer number of the CCO-600 is 3.89 under alkaline medium, which indicates that the reaction mechanism of ORR is dominated by 4 e process similar to commercial Pt. The primary Mg-air battery with the CCO-600 as the cathode catalyst has been assembled and possesses better discharge performance than the CuCo-based PBA. The open circuit voltage of CCO-600 arrives at 1.76 V and the energy density reaches 1895.95 mWh/g. This work provides an effective strategy to develop non-noble metal ORR catalyst for the application of metal-air batteries.

Electrochemical Behavior and Discharge Performance of Extruded Dilute Mg-Bi-Based Alloy as an Anode for Primary Mg-Air Battery

Electrochemical Behavior and Discharge Performance of Extruded Dilute Mg-Bi-Based Alloy as an Anode for Primary Mg-Air Battery

Influence of Sodium 5-Sulfosalicylate as a Corrosion Inhibitor in Nacl Electrolyte on Enhanced Performances of Mg-Air Batteries

Influence of Sodium 5-Sulfosalicylate as a Corrosion Inhibitor in Nacl Electrolyte on Enhanced Performances of Mg-Air Batteries

Elucidating the Dependence of Electrochemical Behavior and Discharge Performance on the Grain Structure of Lean Mg-0.3bi-0.3ag-0.3in Anodes in Primary Mg-Air Battery

Elucidating the Dependence of Electrochemical Behavior and Discharge Performance on the Grain Structure of Lean Mg-0.3bi-0.3ag-0.3in Anodes in Primary Mg-Air Battery

The discharge performance of an as-extruded Mg-Zn-La-Ce anode for the primary Mg-air battery

We investigated the electrochemical properties and discharge performance of La-rich Mischmetal modified Mg-2Zn as candidate anode materials for the Mg-air primary battery. Alloying introduced tiny Mg-Zn-La-Ce second-phase particles into the Mg matrix. The Mg-2Zn-La-Ce anode had a stable discharge voltage higher than that of Mg-2Zn, because of the high open circuit voltage and smooth exfoliation of corrosion products. The best discharge capacity was 1311 mAh g−1 and 60% anodic efficiency at 40 mA cm−2, which were 44% and 45% higher than for Mg-2Zn. The good discharge performance was attributed to less self-corrosion and a suppressed anodic hydrogen reaction.

Achieving Ultrahigh Anodic Efficiency via Single-Phase Design of Mg-Zn Alloy Anode for Mg-Air Batteries.

Magnesium-air battery has been considered promising for electrochemical energy storage or as a conversion device due to its high theoretical energy density and low cost. However, the experimental energy density is far lower than the theoretical value due to the intense hydrogen evolution of the Mg anode upon discharging. Herein, we have successfully developed a novel Mg64Zn36 (at. %) alloy via single-phase design. The as-prepared Mg64Zn36 anode possesses a high discharge specific capacity of 1302 ± 70 mAh g-1 and extraordinarily high efficiency of 94.8 ± 4.9%, which breaks the records of efficiency among all of the reported Mg anodes. The superior high efficiency is attributed to the anodic hydrogen evolution being inhibited by Zn alloying, which passivates the Mg matrix. The intermediate ion Mg+ produced during discharging is dramatically limited by the integrated passive film and is totally converted into Mg2+ electrochemically through the film. Meanwhile, the uniform discharging products due to the homogeneous microstructure of Mg64Zn36 co-contribute to the high efficiency. The design of the Mg-Zn alloy may open a new avenue for the development of Mg-air batteries.

Electrochemical behaviors and discharge performance of Mg-Sn binary alloys as anodes for Mg-air batteries

In this work, the self-corrosion and discharge performance of the as-cast Mg-xSn (x = 1, 5, 9 wt%) anodes for primary Mg-air batteries were studied through microstructure characterization, electrochemical testing and discharge experiments. With the increase of Sn content, the volume fraction of the Mg2Sn phase increases, promoting dendrite refining. According to the electrochemical test, the Mg-1Sn anode shows a higher open circuit potential, resulting in a stronger electrochemical activity. The polarization curve and electrochemical impedance spectra show the corrosion resistance order as Mg-1Sn > Mg-5Sn > Mg-9Sn. In the discharge measurement, the Mg-1Sn anode achieves the best average discharge voltage, anode efficiency, specific capacity, and energy density under all current densities tested. At 10 mA cm−2, the energy density of Mg-1Sn is 1239.621 mWh g−1, which is higher than the Mg-5Sn anode and Mg-9Sn anode, 37% and 25%, respectively. The optimal discharge performance of the Mg-1Sn anode is mainly attributed to the high electrochemical activity and the micron-sized Mg2Sn phase dispersed in the matrix, which facilitates more uniform dissolution.

Magnesium alloys as anodes for neutral aqueous magnesium-air batteries

Magnesium (Mg) is abundant, green and low-cost element. Magnesium-air (Mg-air) battery has been used as disposable lighting power supply, emergency and reserve batteries. It is also one of the potential electrical energy storage devices for future electric vehicles (EVs) and portable electronic devices, because of its high theoretical energy density (6.8 kWh•kg −1 ) and environmental-friendliness. However, the practical application of Mg-air batteries is limited due to the low anodic efficiency of Mg metal anode and sluggish oxygen reduction reaction of air cathode. Mg metal as an anode material is facing two main challenges: high self-corrosion rate and formation of a passivation layer Mg(OH) 2 which reduces the active surface area. In last decades, a number of Mg alloys, including Mg-Ca, Mg-Zn, commercial Mg-Al-Zn, Mg-Al-Mn, and Mg-Al-Pb alloys, have been studied as anode materials for Mg-air batteries. This article reviews the effect of alloying elements on the battery discharge properties of Mg alloy anodes. The challenges of Mg-air batteries are also discussed, aiming to provide a depth understanding for the theoretical and practical development of high-performance Mg-air batteries.

Microstructure and battery performance of Mg-Zn-Sn alloys as anodes for magnesium-air battery

Four Mg-xZn-ySn (x = 2, 4 and y = 1, 3 wt.%) alloys are investigated as anode materials for magnesium-air (Mg-air) battery. The self-corrosion and battery discharge behavior of these four Mg-Zn-Sn alloys are analyzed by electrochemical measurements and Mg-air battery tests. The results show that addition of Sn stimulates the electrochemical activity and significantly improves the anodic efficiency and specific capacity of Mg-Zn alloy anodes. Among the four alloy anodes, Mg-2Zn-3Sn (ZT23) shows the best battery discharge performance at low current densities (≤ 5 mA cm−2), achieving high energy density of 1367 mWh g−1 at 2 mA cm−2. After battery discharging, the surface morphology and electrochemical measurement results illustrate that a ZnO and SnO/SnO2 mixed film on alloy anode surface decreases self-corrosion and improves anodic efficiency during discharging. The excessive intermetallic phases lead to the failure of passivation films, acting as micro-cathodes to accelerate self-corrosion.

Corrigendum to “Ca/In micro alloying as a novel strategy to simultaneously enhance power and energy density of primary Mg-air batteries from anode aspect” [J. Power Sources 472 (2020) 228528

Corrigendum to “Ca/In micro alloying as a novel strategy to simultaneously enhance power and energy density of primary Mg-air batteries from anode aspect” [J. Power Sources 472 (2020) 228528

Mg–Sn Alloys as Anodes for Magnesium-Air Batteries

Three Mg–Sn alloys (with Sn contents of 1, 3, and 5 wt%) were investigated as anodes for magnesium-air batteries. The effect of Sn addition on the microstructure, electrochemical behaviour and battery discharge properties of Mg alloys was studied. Addition of Sn improves the operational voltage of Mg at low to high current densities. At low current densities ≤2 mA·cm−2, Mg-5Sn exhibits better battery discharge performance than pure Mg and other Mg–Sn alloy anodes. At current densities higher than 5 mA·cm−2, Mg-1Sn delivered the best battery discharge performance, evidenced by an anodic efficiency of 51.7%, specific capacity of 1133 mAh g−1 and specific energy density of 1208 mWh g−1 at 10 mA·cm−2. The underlying mechanism by which Mg–Sn alloys improve Mg-air battery performance is discussed.

Development and Demonstration of Pilot Scale Metal-Air Flow Battery for Ultra-Large Capacity Energy Storage System

Recently, novel concepts of electrochemical cells have been spotlighted for ultra-charge energy storage system. Among these cells, magnesium alloy (AZ31) air batteries have attracted much attention as promising energy conversion devices due to their high theoretical energy density, eco-friendly materials and low fabrication cost. Although AZ31–air battery is a primary battery, the AZ31–air battery can be re-used or recharged mechanically by replacing the consumed AZ31 anode and turbid electrolyte with a fresh AZ31 anode and electrolyte, refering to “re-fuelable” During the discharge process, the AZ31 anode is oxidized to ionized Mg, producing two electrons, while at the opposite carbon air-cathode, oxygen molecules pass through the gas diffusion layer and is then reduced to OH− by reaction with H2O and electrons. The theoretical voltage of the AZ31–air battery is 1.2 V and the specific energy density is 2.2 kW h kg−1. Though AZ31–air batteries have a relative high voltage and energy density, there are still scientific problems limiting their pilot scale application. The main issue of cell is the high polarization and low coulombic efficiency. These problems are caused by the corrosion of the metal anode arising from the reaction of metal ions and the electrolyte, and the sluggish by-product kinetics in the air-cathode. In this work, we combined Mg-air batteries with electrolyte flow system, called metal-air flow battery (MAFB) in order to enhance the discharge properties and lifetime by solving the sluggish by-product problems. The components of anode and electrolyte were AZ31 (magnesium alloy) as a fuel and 18wt% saline aqueous solution. The circulation of electrolyte flow efficiently reduces the coagulation of Mg(OH)2 by-product in the unit-cells. As a result, the anode surface efficiency has increased from 72 to above 90 % after the use of flow system. In addition, we have successfully design and developed the metal-air flow battery from unit-cell to rack system. The rack system is made up of 25 series of electrically wired unit-cells for modules and 4-level of modules with electrolyte flow system. The flow system conducted simultaneously in each unit-cells by electrolyte supply tank in the top and by-product filter tank in the bottom. From the rack system, a pilot scale MAFB with 400 pieces of unit-cells was developed and fabricated for ultra-large energy storage system. The 704 kWh of energy storage system demonstrated by 25s-16p electrical wiring with 4-rack flow systems. As a result, it is the first report about the MAFB using AZ31 anodes in pilot-scale energy storage system. It has shown a large potential for future energy conversion devices for smart grid applications. Figure 1

The influence of Ga alloying on Mg-Al-Zn alloys as anode material for Mg-air primary batteries

This paper investigates the microstructure, corrosion, electrochemical behavior, and the discharge performance of Gallium (Ga) alloyed Mg-Al-Zn alloys using the gravimetric method, electrochemical measurements, and battery test. The average grain size of AZ80–2.5Ga (Mg-8Al-0.5Zn-2.5Ga alloy) is 36% smaller than that of AZ80 (Mg-8Al-0.5 Zn alloy). The number and size of the Mg17Al12 phase particles are smaller and more homogeneously distributed. Ga reduces the self-corrosion rate, increases the electrochemical activity and the discharge performance. The grain refinement generates many grain boundaries on the surface and promotes discharge performance. The decrease of the self-corrosion rate is attributed to the suppression of the protective film that inhibits the anode consumption. The AZ80–2.5Ga anode has the optimal discharge capacity of 1437 mAh g− 1 and anode efficiency of 61% at 50 mA cm−2, which are 25% and 29% higher than for the AZ80 anode.

Controlling Magnesium Self-Corrosion in Mg-Air Batteries with the Conductive Nanocomposite PANI@3D-FCNT.

A promising potential device for storage of large amounts of energy is Mg–air batteries. However, the corrosion of the Mg electrode inside the battery electrolyte limits the battery’s capacity to store energy. We present a new strategy to protect the Mg electrode from corrosion and increase the life cycle of Mg batteries in this article. The Mg electrode is coated with a conductive nanocomposite (PANI@3D-FCNT) in this technique. To better understand the anticorrosion properties of PANI@3D-FCNTs and their effect on the battery efficiency, electrochemical and battery tests are used. We discovered that PANI@3D-FCNT plays the most promising role in reducing Mg electrode corrosion in 3.5 wt % NaCl electrolyte, with an efficiency of 93.9%. The battery with the coated Mg electrode has a longer discharge time and a slower drop in operating voltage. The PANI@3D-FCNT nanocomposite will prolong the life of the Mg–air battery and keep the Mg electrode active for a long time. This work outstandingly provides an effective strategy to address the defects in the Mg–air batteries arising from electrode corrosion successfully. The work is a great way to open up new avenues for introducing new conductive nanocomposites in metal–air battery designs without using traditional methods.

CuMnO2 Nanoflakes as Cathode Catalyst for Oxygen Reduction Reaction in Magnesium-Air Battery

Developing efficient and stable ORR catalysts for Mg-air batteries is crucial to enabling extensive applications. Herein, CuMnO2 nanoflakes were synthesized with a facile one-step hydrothermal way and applied as the cathode catalyst for Mg-air batteries. The ORR activities in alkaline and neutral electrolyte were then investigated. The half-wave potential has a minus variation of 22 mV after 5000 cycles, indicating the outstanding stability of the CuMnO2. The electron transfer number of the CuMnO2 is 3.70 under neutral condition, which demonstrates that the reaction process of ORR is equivalent to the commercial Pt catalyst. Moreover, the primary Mg-air battery with CuMnO2 as the cathode catalyst was assembled and the discharge properties were tested. The open circuit voltage achieved was 1.78 V and the operating voltage remained about 1.36 V after 22 h operation at 1.0 mA·cm−2. It is evident that the CuMnO2 nanoflake is an effective catalyst to accelerate the reaction rate of ORR process in Mg-air battery. This work provides a novel approach for the subsequent exploration of non-noble metal catalysts for Mg-air batteries.

AS61 Magnesium Alloy with Nano-Scale Mg2Sn Phase as a Novel Anode for Primary Aqueous Magnesium Battery

A novel AS61 magnesium alloy is prepared via the small-hole confinement of liquid alloy by using a thick-walled copper mould. This facile method gives rise to distinct grain refinement and dispersed second phases such as nano-scale Mg2Sn (12.54 3.35 nm). Benefiting from the unique microstructure, the AS61 shows enhanced anode performance when adopted for primary aqueous battery, as compared with that using the anode of the same composition fabricated via a common iron mould during melting and casting. The Mg-air battery with the novel AS61 anode provides a high voltage of 1.269 V at 10 mA cm−2; its anodic efficiency at 10 mA cm−2 reaches 78.4%, which is higher than lots of other types of magnesium anodes. Moreover, the discharge mechanism of AS61 is also unravelled based on electrochemical response and microstructure characterization.

Discharge properties of Mg-Sn-Y alloys as anodes for Mg-air batteries

Discharge properties of Mg-Sn-Y alloys as anodes for Mg-air batteries

Cu ion doping α-MnO2 nanowire electrocatalysts for Mg-air battery

Cu ion doping α-MnO2 nanowire electrocatalysts for Mg-air battery

Enhancement of discharge performance for aqueous Mg-air batteries in 2,6-dihydroxybenzoate-containing electrolyte

In this work, 2,6-dihydroxytbenzoate (2,6-DHB) is evaluated as an efficient electrolyte additive for aqueous Mg-air batteries based on diverse metallic Mg anodes. EIS measurements amid intermittent discharge and real-time hydrogen evolution measurements during discharge were applied to clarify the effective mechanism. The dependence of working mechanism on 2,6-DHB concentration was investigated for a newly developed Mg-0.15Ca anode. The results reveal that sufficient amount of 2,6-DHB simultaneously improves the discharge activity and inhibits the self-discharge of Mg-0.15Ca anode, leading to negative average potential and high anodic utilization efficiency. Accordingly, 0.2 M 2,6-DHB is determined as the most suitable electrolyte concentration and applied during Mg-air battery tests based on diverse commercial Mg anodes (pure Mg, Mg-0.15Ca, AZ31 and AM50). The results demonstrate that 2,6-DHB efficiently improves the discharge performance of Mg-air batteries with different Mg anodes.

Micro-Alloyed Mg-Al-Mn-La Anode for Mg-Air Batteries

Herein, we propose a novel Mg-based micro-alloyed Mg-1Al-0.3Mn-0.3La (wt%) anode to obtain enhanced discharge characteristics in an Mg-air battery. In this study, comparisons are made with the Mg-1Al-0.3Mn alloy and commercial Mg-6Al-0.3Mn. Adding La in the Mg-1Al-0.3Mn-0.3La alloy inhibits the hydrogen evolution both at open circuit potential and under the condition of anode polarization but promotes a rapid anode dissolution. Furthermore, adding La can tune the microstructure of Mg-1%Al-0.3%Mn towards uniform dissolution and limit the chunk effect when used as an anode in the Mg-air battery system. Moreover, the intermetallic Al2La phase is shown to be critical in the formation and peeling off the loose-knit oxidation products. Thus, we report that the voltage and energy density of the Mg-air cell improved by adopting the Mg-1%Al-0.3%Mn-0.3%La anode, making it an excellent anode candidate for future practical applications.