Aluminum-ion Batteries Research Articles

Advances in the Field of Graphene-Based Composites for Energy–Storage Applications

To meet the growing demand in energy, great efforts have been devoted to improving the performances of energy–storages. Graphene, a remarkable two-dimensional (2D) material, holds immense potential for improving energy–storage performance owing to its exceptional properties, such as a large-specific surface area, remarkable thermal conductivity, excellent mechanical strength, and high-electronic mobility. This review provides a comprehensive summary of recent research advancements in the application of graphene for energy–storage. Initially, the fundamental properties of graphene are introduced. Subsequently, the latest developments in graphene-based energy–storage, encompassing lithium-ion batteries, sodium-ion batteries, supercapacitors, potassium-ion batteries and aluminum-ion batteries, are summarized. Finally, the challenges associated with graphene-based energy–storage applications are discussed, and the development prospects for this field are outlined.

Experimental Study on Temperature Sensitivity of the State of Charge of Aluminum Battery Storage System

The operating temperature of a battery energy storage system (BESS) has a significant impact on battery performance, such as safety, state of charge (SOC), and cycle life. For weather-resistant aluminum batteries (AlBs), the precision of the SOC is sensitive to temperature variation, and errors in the SOC of AlBs may occur. In this study, a combination of the experimental charge/discharge data and a 3D anisotropic homogeneous (Ani-hom) transient heat transfer simulation is performed to understand the thermal effect of a novel battery system, say an aluminum-ion battery. The study conducts a turbulence fluid dynamics method to solve the temperature distribution of the battery rack, and the entropy generation method analyzes the heat generation of AlB during the charging/discharging process. The AlB is modeled by a second-order Thevenin equivalent circuit to estimate the status of the battery. An extended Kalman filter is applied to obtain the accurate SOC for monitoring the battery cell. The current study conducts the Galvanostatic Intermittent Titration Technique (GITT) on aluminum-ion batteries under different operation temperatures: 25 °C, 40 °C, 60 °C, and 80 °C. According to the sensitivity analysis of the SOC, the temperature sensitivity tends to or greater than one, ST≥1, while the operation temperature is above 40 °C, and the SOC modification of EKFtmep estimator improves the battery state of charge in the error range below 1%.

Al3+ ion storage in LiMnPO4 for rechargeable aqueous aluminum-ion battery

Herein, we demonstrate the Al3+ ion electrochemical activity of LiMnPO4 in aqueous electrolyte. It is found that LiMnPO4 can store Al3+ ion and it possesses two discharge plateaus at 1.09 V and 0.86 V (vs Ag/AgCl). The initial discharge capacity is as high as 146 mAhg−1 at a current rate of 1 Ag−1 with capacity retention of 50 mAhg−1 over 450 cycles at current rate of 2.5 Ag−1. A functional rechargeable aqueous Al3+ ion cell is also demonstrated with LiMnPO4 as cathode and WO3 as anode. The cell shows discharge plateau in the potential range of 1–1.4 V with excellent cycling stability.

Application of purified kish flake graphite as a potential cathode material for high-performance aluminum ion batteries

The separation and purification of kish graphite is an important prerequisite for its high value and comprehensive utilization. The comprehensive separation process including water washing dust removal, magnetic separation and acid leaching purification can effectively enrich and purify kish flake graphite (KFG) from low-cost industrial by-product kish graphite. When the magnetic strength is 2000 Gauss, the purified KFG has suitable recovery (57.34%), high fixed carbon content (99.38%) and low ash content (0.62%). Compared with natural flake graphite, KFG has a highly ordered graphite microcrystalline layer structure with higher graphitization degree (99.77%) and well-developed micro/nanopore with larger specific surface area (4.12 m2·g−1). Such distinctive microstructure features ensure KFG to be applied as a cathode material for aluminum ion batteries (AIBs) to exhibit superior electrochemical behaviors. KFG exhibits a high reversible specific capacity (110.7 mAh/g at 50 mA/g), outstanding rate capability (56.9 and 26.6 mAh/g at high current densities of 1000 and 2000 mA/g) and superior long-term cycling stability (101.8 mAh/g with a Coulombic efficiency of 99.5% at 1000 mA/g after 2000 cycles). This study demonstrates a promising feasibility for mass production of KFG from industrial by-product kish graphite for high performance AIBs.

Ultra-high-performance aluminum-based hybrid supercapacitors prepared for nitrogen-doped micro-mesoporous carbon sphere

Aluminum-based devices are promising candidates for the next generation of energy storage due to the advantages of high energy density, high safety, and low cost. The aluminum ion batteries (AIBs) are based on the electrochemical intercalation/deintercalation reactions against the electrodes, but the selection of the cathode is limited to the present. The cathode reactions of cation-type AIBs are plagued by the poor kinetics of solid-state diffusion from high charge density of Al3+ and anion-type AIBs show poor capacity due to the intercalation of large-sized chloroaluminate (AlCl4−) active ions into the cathode. Here, we deliberately adopted a hybrid capacitor-battery mechanism and employed a nitrogen-doped micro-mesoporous carbon sphere of a high specific area as the cathode and aluminum as the anode to construct an aluminum-based energy storage device. After optimization, it exhibits an excellent discharge capacity of 224 mA h g−1 at a current density of 300 mA g−1, and exceptional cycling performance with a discharge capacity as high as 114 mA h g−1 at 10 A g−1 after 35000 cycles. The ultra-high-performance aluminum-based hybrid supercapacitor (Al-HSC) may lead to a new direction for the development of aluminum-based energy storage devices.

Selection principles of polymeric frameworks for solid-state electrolytes of non-aqueous aluminum-ion batteries.

Liquid electrolyte systems of aluminum-ion batteries (AIBs) have restrictive issues, such as high moisture sensitivity, strong corrosiveness, and battery leakage, so researchers have turned their attention to developing high safety, leak-free polymer electrolytes. However, the stability of the active factor of AIB systems is difficult to maintain with most of polymeric frameworks due to the special Al complex ion balance in chloroaluminate salts. Based on this, this work clarified the feasibility and specific mechanism of using polymers containing functional groups with lone pair electrons as frameworks of solid-state electrolytes for AIBs. As for the polymers reacting unfavorably with AlCl3, they cannot be used as the frameworks directly due to the decrease or even disappearance of chloroaluminate complex ions. In contrast, a class of polymers represented by polyacrylamide (PAM) can interact with AlCl3 and provide ligands, which not only have no effect on the activity of Al species but also provide chloroaluminate complex ions through complexation reactions. According to DFT calculations, amide groups tend to coordinates with AlCl2 + via O atoms to form [AlCl2(AM)2]+ cations, while disassociating chloroaluminate anions. Furthermore, the PAM-based solid-state and quasi-solid-state gel polymer electrolytes were also prepared to investigate their electrochemical properties. This work is expected to provide new theoretical and practical directions for the further development of polymer electrolytes for AIBs.

Preintercalated Copper Hexacyanoferrate as a Long-Time Cycle Cathode Material for Aqueous Aluminum-Ion Batteries

Preintercalated Copper Hexacyanoferrate as a Long-Time Cycle Cathode Material for Aqueous Aluminum-Ion Batteries

CMK3 collaborated with SexSy to build high-performance rechargeable aluminum-ion batteries

The development of rechargeable aluminum batteries (RABs) has consistently relied on the logical selection and design of cathode materials. Se has a high electrical conductivity while S has a high theoretical specific capacity; yet, both materials are known to present lethal shuttle effects, space expansion, and slow reaction kinetics. The development of RABs will be accelerated if the synergistic properties of both materials can be utilized. Various ratios of SexSy as the cathode materials for RABs, and a series of electrochemical tests are shown in this work. The rise in the ratio of Se and S leads to the improvement of the cycling performance. However, the shuttle effect of Se and S has a fatal blow to the performance of the battery. To solve this problem, (mesostructured carbon materials) CMK3 modified separators were employed between the cathode and anode to further limit the dissolution of Se, considerably improving the utilization of the active materials. Therefore, initial capacity of Al/GF/C@CMK-3/SexSy is about 539.4 mAh g−1 and reversible capacity of 314.2 mAh g−1 was likewise maintained after 500 cycles at 1.0 A g−1. RABs based on Al/S and Al/Se batteries have promising research avenues opened up by Al/SexSy batteries based on CMK3 modified separators.

Effects of Multiple Ion Reactions Based on a CoSe2 /MXene Cathode in Aluminum-Ion Batteries.

Rechargeable aluminum-ion batteries (RAIBs) have emerged as a promising battery storage technology owing to their cost-effectiveness, operational safety, and high energy density. However, their actual capacity is substantially lower than their true capacity and their cycling stability is poor. Therefore, understanding the energy-storage mechanism may contribute to the successful design of a stable electrode material, on which the performance can be optimized. The aim of this study is to investigate AlCl4 - ions in transition metal cathode materials and mechanisms that enable for their high-energy-storage potential and low Coulombic efficiency. Results of theoretical analysis and experimental verification show that a multi-ion transport mechanism is responsible for the electrochemical behavior of the battery. The lattice distortion of CoSe2 caused by AlCl4 - ion intercalation, has a considerable effect on the initial stability of the battery. MXene as a support material reduces the size of CoSe2 growing on its surface, effectively inhibiting the lattice distortion caused by the interaction with the aluminum-anion complex, thus addressing the issues of poor reversibility, cycle instability, and low Coulombic efficiency of the battery. Hence, understanding the impact of MXene on the battery may aid in further improving the design of electrode materials.

Organic Cathode Materials for Rechargeable Aluminum-Ion Batteries.

Organic electrode materials (OEMs) have shown enormous potential in ion batteries because of their varied structural components and adaptable construction. As a brand-new energy-storage device, rechargeable aluminum-ion batteries (RAIBs) have also received a lot of attention due to their high safety and low cost. OEMs are expected to stand out among many traditional RAIB cathode materials. However, how to improve the electrochemical performance of OEMs in RAIBs on a laboratory scale is still challenging. This work reviews and discusses the uses of conductive polymers, carbonyl compounds, imine polymers, polycyclic aromatic hydrocarbons, organic frameworks, and other organic materials as the cathodes of RAIBs, as well as energy-storage mechanisms and research progress. It is hoped that this Review can provide the design guidelines for organic cathode materials with high capacity and great stability used in aluminum-organic batteries and develop more efficient organic energy storage cathodes.

Aqueous Binders Compatible with Ionic Liquid Electrolyte for High-Performance Aluminum-Ion Batteries.

The incompatibility of poly(vinylidene difluoride) (PVDF) with acidic ionic liquid electrolytes and the use of toxic and high-cost N-methyl pyrrolidone (NMP) solvents hinder the wide application of aluminum-ion batteries (AIBs). In this work, sodium alginate (Na-Alg) is developed as an aqueous binder for the fabrication of graphite positive electrodes in AIBs. The compatibility of various binders with the ionic liquid electrolyte is evaluated, and interaction between various binders and graphite particles before and after cycling is compared and discussed. The results demonstrate that the well compatibility of Na-Alg in ionic liquids and its reasonable distribution on the graphite surface facilitate fast charge transfer and ion diffusion, reduce electrode polarization, and thus contributing to significantly improved cycling stability and rate capability of AIBs. This work provides a new insight into the development of low-cost, eco-friendly, and high-performance binders for AIBs.

Organopolysulfides as high-performance cathode materials for rechargeable aluminum-ion batteries

The development of aluminum-ion batteries (AIBs) is significantly confined by the limited high-performance cathode materials. Herein, organopolysulfides are investigated as active cathode materials to fabricate AIBs. A liquid-phase phenyl tetrasulfide (PTS) can deliver a capacity above 600 mAh g−1 after activation, with the maintenance of 253 mAh g−1 after 100 cycles. Owing to the different S locations, PTS shows several voltage plateaus and an average voltage of ∼0.7 V vs. Al3+/Al with no decay upon cycling. More importantly, the liquid PTS can serve as a high-Coulombic-efficiency cathode (∼99.88% ± 0.57% after stabilization), enlighting the design of high-efficiency and low-resistance conversion-type cathode materials for AIBs. By experimental characterizations accompanied by theoretical calculations, it is found that PTS undergoes stepwise reaction procedures during discharge with final products of Al2S3 and AlCl2-coordinated phenyl sulfide, and partially reforms with elemental S and other organopolysulfides during charge. This study demonstrates new opportunities for the design of high-efficiency conversion-type cathode materials for advanced AIBs.

Research Progress of Cathode Materials for Rechargeable Aluminum Batteries in AlCl3/[EMIm]Cl and Other Electrolyte Systems

AbstractThe development of safe, cheap, and environmentally friendly advanced rechargeable batteries with high energy density are one of the most pressing tasks for today‘s energy crisis. With the advantages of low cost, abundant reserves, and high‐level safety, rechargeable aluminum ion batteries are considered ideal candidates for next‐generation energy storage batteries in the context of large‐scale energy applications. Relevant knowledge of energy storage materials and electrolytes, which possess close connection in between, is undeniably crucial for such research, while ironically, most attention is attracted to merely one element alone, especially the energy storage materials involving micro/nanomaterials. In this review, we focus on cathode materials matching with various electrolyte systems for rechargeable aluminum batteries and manage to provide new ideas for the preparation methods of high‐efficiency electrochemical energy storage materials, with future outlooks in this field.

The Negative-Charge-Triggered "Dead Zone" between Electrode and Current Collector Realizes Ultralong Cycle Life of Aluminum-Ion Batteries.

Typically, volume expansion of the electrodes after intercalation of active ions is highly undesirable yet inetvitable, and it can significantly reduce the adhesion force between the electrodes and current collectors. Especially in aluminum-ion batteries (AIBs), the intercalation of large-sized AlCl4 - can greatly weaken this adhesion force and result in the detachment of the electrodes from the current collectors, which seems an inherent and irreconcilable problem. Here, an interesting concept, the "dead zone", is presented to overcome the above challenge. By incorporating a large number of OH- and COOH- groups onto the surface of MXene film, a rich negative-charge region is formed on its surface. When used as the current collector for AIBs, it shields a tiny area of the positive electrode (adjacent to the current collector side) from AlCl4 - intercalation due to the repulsion force, and a tiny inert layer (dead zone) at the interface of the positive electrode is formed, preventing the electrode from falling off the current collector. This helps to effectively increase the battery's cycle life to as high as 50000 times. It is believed that the proposed concept can be an important reference for future development of current collectors in rocking chair batteries.

Effects of molecular structure and functional groups on the performance of carbonyl organic compounds as cathodes for aluminum batteries

Organic electrode materials have received extensive and long-term research and attention due to their safety, environmental friendliness, and lower price, and have also been used in aluminum-ion batteries (AIBs). The performance of existing applications in AIBs using organics as cathode materials still lags behind inorganics, especially in terms of battery capacity and voltage. Carbonyl groups have great potential as active sites for redox reactions in AIBs. Here, six carbonyl organic compounds were used as cathode for AIBs to investigate their performance differences and the factors affecting the performance. Through a combination of experiments and theoretical calculations (DFT), BDTO was first identified as the best performing cathode material in six organics, leading the organic materials with a high specific capacity of 236.8 mAh g−1 and 500 stable cycles. Moreover, it is proved that the symmetry of ring structure and molecular structure has an important influence on the properties of organic cathodes. These research results provide a direct reference for the selection and design of rational organic as cathode materials, which is an important step on the road to develop high-performance aluminum-organic batteries as soon as possible.

Realizing the Long Lifespan of Molybdenum Trioxide in Aqueous Aluminum Ion Batteries Through Potential Regulation

Realizing the Long Lifespan of Molybdenum Trioxide in Aqueous Aluminum Ion Batteries Through Potential Regulation

Long-chain alkylammonium organic–inorganic hybrid perovskite for high performance rechargeable aluminon-ion battery

Recent advances in the use of organic-inorganic hybrid perovskites have been investigated in a variety of applications, such as solar cells, photodetectors, light-emitting devices, and lasers, because of their outstanding semiconductor properties. Furthermore, the perovskite structure can host extrinsic elements, making it a promising candidate for battery applications. Previous studies have shown that organic-inorganic hybrid perovskites can be suitable anode materials for both lithium- and sodium-ion batteries. However, multivalent rechargeable batteries with perovskite materials have not yet been realized. Herein, we studied the electrochemical performance of three-dimensional (CH3NH3PbI3 (MAPbI3) and long-chain alkylammonium (C4H9NH3)2(CH3NH3)3Pb4I13 ((iBA)2(MA)3Pb4I13) thin films as electrode materials for rechargeable Al-ion batteries. Our results showed that (iBA)2(MA)3Pb4I13 presented a specific capacity of 257 mAh g–1 at a current density of 0.1 A g−1 and delivered 108 mAh g–1 after 250 cycles at a current density of 0.3 A g−1 with a retention of as high as 91 %, demonstrating a crucial role of isobutyl amine (C4H9NH3) due to the unique hydrogen-bonding interaction of isobutyl amine that hinders the shuttle effect of polyiodide. The results open a new direction for the use of organic–inorganic hybrid perovskites for new secondary aluminum ion batteries.

ZnSe/SnSe2 hollow microcubes as cathode for high performance aluminum ion batteries

Advances in cathode material design and understanding of intercalation mechanisms are necessary to improve the overall performance of aluminum ion batteries. Therefore, we designed ZnSe/SnSe2 hollow microcubes with heterojunction structure as a cathode material for aluminum ion batteries. ZnSe/SnSe2 hollow microcubes with an average size of about1.4 µm were prepared by selenization of ZnSn(OH)6 microcubes successfully. The shell thickness of ZnSe/SnSe2 hollow microcubes is about 250 nm. On one hand, the hollow cubic structure can effectively alleviate the volume effect, provide shorter ion diffusion paths, and increase the contact area with the electrolyte. On the other hand, ZnSe/SnSe2 heterojunction structure can establish a built-in electric field to facilitate ion transport. The synergistic effect of the two leads to the improved electrochemical performance of ZnSe/SnSe2 as the cathode of aluminum ion batteries. The material delivered a reversible capacity of 124 mAh/g after 150 cycles at a current density of 100 mA/g. Meanwhile, coulombic efficiency remained above 98% in almost all cycles. In addition, the electrochemical reaction mechanism and kinetic process of Al3+ and ZnSe/SnSe2 were studied.

Phytic acid-doped and ammonium hydroxide de-doped polyaniline cathodes for rechargeable aluminum ion battery

Rechargeable aluminum ion battery (RAIB) is a very promising large-scale energy storage scheme attributed by the advantages of aluminum with large theoretical capacity, high energy density, low cost, abundant earth resources and environment friendliness. The selection and preparation of cathode materials are crucial for the electrochemical performance of RAIB. In this study, the specific capacity and cycle life of RAIB were improved by using polyaniline doped with phytic acid and further optimized by ammonium hydroxide de-doping treatment. Phytic acid doping improves the spatial configuration of polyaniline, making the nanostructure more hierarchical and increasing the specific surface area. More importantly, ammonium hydroxide treatment provides more chemical reaction sites while maintaining hierarchic structural morphology of the material. Due to the advantages above, the de-doped polyaniline cathode obtains an initial discharge-specific capacity of the initial cycle is 78.1 mAh g−1 at a high current density of 1 A g−1. After cycling of 2000, the capacity loss is only 16.7%, and an average decay rate of 0.007% per cycle with the Coulomb efficiency remains about 100% after cycling of 5000. At the same time, the contribution of pseudo capacitance and working mechanism are investigated. The capacity contribution of RAIB has been divided into diffusion-control, surface-control and double-layer, which is more consistent with the actual situation and further deepens the understanding of the charging-discharging mechanism of RAIB. These results are expected to lay a foundation for the future development of RAIB systems for large-scale energy storage using organic polymers as cathode materials.

Establishment of second-order equivalent circuit model for bidirectional voltage regulator converter: 48 V-aluminum-ion battery pack

The establishment of an equivalent circuit model for new-generation battery packs is an important issue related to the safety of future energy storage systems. In this study, an aluminum-ion battery pack model is accurately built by performing a hybrid pulse power characterization (HPPC) experiment, along with a synchronous regulator converter electric-circuit model of the resistor–capacitor (RC) equivalent circuit. This approach proves the feasibility of the proposed model via field testing and simulation, thereby underscoring its capability to precisely depict the exterior features of the battery discharging behavior and its advantages and disadvantages, as well as suggestions for improvement. From the analysis results, the convergent efficiency is found to exceed 90%. The simulation error was smaller than 0.08 V. The system can be incorporated with the function of current feedback to suppress current surge and stabilize battery output as well as to prevent voltage surges and damage to components caused by impulses when a load is applied.