AnodeAnode changing, a major production operation in aluminum electrolysisAluminum electrolysis, is the primary cause of zone anode currentZone anode current fluctuations in reduction cellsReduction cell, significantly reducing the zone’s anodeAnode current. As the new anodeAnode heats up and participates in electrochemical reactions, the zone current gradually recovers. During recovery, the zone anode currentZone anode current curve may show one or more of three stages: linear, steady, and step-up. The steady stage likely stems from slow dissolutionDissolution of solidified electrolyteElectrolyte on the new anodeAnode surface, while the step-up stage (≈6.2 kA) mostly results from anodeAnode changing in an adjacent zone. AnodeAnode current recoveryCurrent recovery in the anode changeAnode change zone falls into three modes. Among them, the linear-based mode (about 35

As one of the most common faults in zinc electrowinning cells, inter-electrode short circuits obviously reduce the current efficiency and increase energy consumption, so their timely online identification has great practical significance. Existing methods including infrared imaging and Gaussmeter suffer from problems such as delayed detection (more than 30 min after faults) and high false alarm rate. To address this critical issue, this study develops an intelligent method for rapid and accurate online diagnosis of short circuits based on cathode current data and machine learning. The cathodic current curves collected online were initially preprocess using sliding window, smoothing and curve fitting, the short-circuit features parameters were extracted, and then 32 trained models were constructed by using machine learning methods including Random Forest, Support Vector Machine, Neural Network and Gradient Boosted Trees. After optimized and evaluated by cross-validation method, as well as the verification of the test set, one Neural Network model has been chosen as the intelligent diagnosis model to be used for the online diagnosis of inter-electrode short circuits in zinc electrowinning cells, and the model is tested with an accuracy of 91%, showing fairly good diagnostic performance.

The Hall-Héroult aluminum productionAluminum production process can be enhanced by minimizing the anode effect (AEAnode Effect (AE)) occurrences since AEAnode Effect (AE) is detrimental to the process. This study demonstrated that the occurrence of low-voltage anode effectAnode Effect (AE) (LVAE) and its position can be diagnosed effectively according to the change of zone anode currentZone anode current by using the fiber optic current sensorSensors. In the single-zone manual reduced feeding experiments, additional aluminaAlumina was manually fed into the diagnosis zone once its zone anode currentZone anode current continued to drop to a certain threshold, resulting in the successful quenching of LVAE. Subsequently, an automated algorithm was developed and then applied to the single-zone stop feeding experiments. The quenching of LVAE was achieved by feeding the aluminaAlumina automatically into the zone in which the LVAE was present. This method of precise alumina feedingAlumina feeding to LVAE zones automatically can reduce the frequency of anode effectAnode Effect (AE) in electrolysisElectrolysis production processes effectively.

Anode effect (AEAnode Effect (AE)) is a common failure in the aluminum productionAluminum production process due to the numerous negative influences in electrolysis cellsElectrolysis cell. In this paper, the response of zone anode currentZone anode current to AEAnode Effect (AE) was analyzed systematically. The results showed that the zone anode currentsZone anode current in all zones fluctuated dramatically during the occurrence of the global AEAnode Effect (AE). However, in tens of seconds before this, there would always be a zone where the zone anode currentZone anode current first dropped (called the initial response zone, IRZ), with a probability of 59.3

Alternate feeding of two feeder groups with equal rate is commonly employed in high-amperage reduction cellsReduction cell. Both anodeAnode changing and feeding malfunctions cause uneven alumina concentrationAlumina concentration, leading to anode effectsAnode Effect (AE), sludge, and lower current efficiency. Online precise measurementMeasurements technology of zone anode currentZone anode current provides new ideas to improve the alumina concentrationAlumina concentration uniformityUniformity and rapid diagnosis of individual feeding port faults. In this study, the statistical laws and zone resistanceZone resistance response characteristics of underfeeding and overfeeding stages using the zone anode currentZone anode current of a 400kA aluminum reduction cellAluminum reduction cell were analyzed. The differences in the zone resistanceZone resistance changes over time in the same feeding stage were studied. The results of manual-controlled feeding experiments showed that the response of zone resistanceZone resistance to low local alumina concentrationAlumina concentration was weaker than that to high local alumina concentrationAlumina concentration, which may be the combined effects of mass transferMass transfer between zones and the resistance response to alumina concentrationAlumina concentration.

The eta ' phase is recognized for enhancing the strength of Al-Zn-Mg-Cu alloys but compromises their thermal stability due to poor coarsening resistance. Conversely, a dual-phase strengthening system combining eta ' with thermally stable T ' phases offers a strategy to balance strength and thermal stability. Here, we systematically evaluate the high-temperature performance of five peak-aged Al-Zn-Mg-Cu alloys with varying Zn/Mg ratios from 1.50 to 10.00 (Zn: 4.2-8.0 wt%; Mg: 0.8-2.8 wt%), using tensile testing at 200-300 degrees C and creep characterization at 200-300 degrees C under 30-100 MPa. Alloys A3 and A4, featuring high Zn/Mg ratios (2.86-4.44) and solute contents (10.8-11.8 wt%), exhibit exceptional high-temperature tensile strength. In contrast, alloys A1 and A2 with low Zn/Mg ratios (1.50-2.14) and lower solute contents (8.0-9.8 wt%) show superior creep resistance, attributed to their high T '/T phase fraction (>= 80 %). During creep, T '/T phases coarsen more slowly than eta '/eta phases, and these fine-scale precipitates hinder dislocation motion. Although the proportion of precipitates exerts a significant influence on the creep resistance of Al-Zn-Mg-Cu alloys, it appears to be independent of the creep mechanism. Analysis of stress exponents (n) and activation energies (Q) reveals distinct deformation modes at 300 degrees C: at low stress (30-50 MPa), diffusional creep and grain boundary sliding (GBS) coexist in alloys A1, A2, A4, A5 (n = 1.60-1.77), while GBS predominates in A3 (n = 2.52); at higher stress (50-100 MPa), all alloys undergo dislocation climb (n = 4.41-8.11, Q = 141.9-214.4 kJ/mol). This study yields novel insights into the optimization of microstructure and high-temperature properties for heat-resistant aluminum alloys.

In the process of zinc electrowinning, inter-electrode short circuits are one of the most common faults, which has great influence on the variation of cathode current and current efficiency of electrowinning cells. Based on data obtained from the online cathodic current measurement system, this paper analyzes the phenomenon of short circuits between cathode and anode plates and the current response characteristics, and evaluates the problems of current efficiency reduction and current consumption increase due to short-circuiting, which provides a theoretical basis for short circuits early warning and energy efficiency optimization of zinc electrowinning process.

The influence of O2 bubbles on the flow field characteristics of the electrolyte in the zinc electrowinning process was comparatively investigated by coupling a laminar flow module or a laminar bubbly flow module to study the zinc electrowinning process considering O2 bubbles and without considering O2 bubbles, respectively. The research results indicated that a large vortex formed at the top of the region between the anode and cathode, with the maximum flow velocity of the electrolyte reaching 0.065 m/s when considering O2 bubbles; when O2 bubbles were not considered, no vortex formed at the top of the anode and cathode region, and the maximum flow velocity of the electrolyte between the anode and cathode was 2.86×10‐3 m/s.

High-purity copper is widely used due to its excellent physical and chemical properties. However, due to the high production cost, it is difficult for the output of high-purity copper to match market demand in China, leading to a supply-demand imbalance. Therefore, improving preparation technology and increasing production have become key research focuses in China’s high-purity copper field. In this paper, COMSOL Multiphysics software was applied to conduct numerical simulations of the copper electrolysis process for experimental guidance, and the method used by the research group to wrap a filter mesh around the cathode plate for the preparation of high-purity copper was employed. The results showed that by wrapping the filter mesh, the transport mode of Cu 2+ was changed, and the mass transfer mode was changed from convection to both diffusion and electromigration. This transport mode reduced the inter-electrode mass transfer efficiency of Cu 2+ , so the current should not be set too high during the electrolysis process. Further research revealed that reducing the current density not only improved the surface quality of cathode copper but also increased its purity. Finally, by wrapping the filter mesh with a 0.1 μm pore size around the cathode plate and setting the current density at 31 A/m 2 , high-purity cathode copper with the purity close to 5N was successfully obtained.

Abstract Compared with the total current, the current in each parallel branch will help to achieve better battery management for new energy vehicles. However, today, accurate measurement of branch current is very difficult because the space between branches in the power battery pack is very limited. In this study, the fiber-optic current mini-sensor is used to meet this challenge. A saddle-sensing fiber structure has been designed to achieve surface measurement in response to the specific interconnection of circuitry in battery packs. A computer simulation was used to validate the feasibility, and experimental testing showed positive results. The specific experiments confirmed that the relative error between the saddle fiber-optic current sensor and conventional fiber-optic loop current sensor does not exceed 0.0119%. It meets the requirements of the automotive industry standards.

Rechargeable aluminum batteries (RABs) have garnered attention owing to their impressive theoretical capacity, outstanding safety features, and abundant Al reserves, thereby positioning them as a potential alternative and supplement to fixed energy storage. Nonetheless, RABs still suffer from issues, such as poor anode stability stemming from the corrosivity of the chloral aluminate ionic liquid electrolyte (ILs) and subpar wettability of the cathode. To address these issues, the proposed electrolyte interfacial engineering involves the nonionic surfactant (F127) as an interfacial optimizer in ILs, simultaneously modulating the anode-electrolyte and cathode-electrolyte interfaces. Systematic experiments and theoretical analyses validate that F127 preferentially adsorbs on the electrode surface, forming a dense and uniform adsorption layer. The F127 layer can effectively mitigate the corrosion of ILs on the Al anode and regulate the current density to achieve uniform Al deposition. Furthermore, F127 enhances the wettability between the cathode and ILs, preventing the collapse of the graphite structure and enhancing the active material's utilization. The Al//FG full battery assembled with F127 modifying ILs (F127-0.5) is able to retain a specific capacity of 104.9 mAh g-1 after 1600 cycles, which is higher than ILs (69.0 mAh g-1). This electrolyte interface modification strategy holds considerable practical significance for achieving long-lifespan and high-capacity RABs. An optimized electrode/electrolyte interface engineering strategy is developed by introducing amphiphilic non-ionic surfactants (F127) for achieving a dendrite-free Al anode and self-activated graphite cathode. The assembled Al//graphite battery with F127 optimizer can sustain a stable cycle of 1600 cycles at 0.5 A g-1, and its capacity is maintained at 104.5 mAh g-1, which is significantly better than pure ILs, its capacity decays to 69.0 mAh g-1. image

Hierarchical microstructures spanning from micro-sized eutectic structure to nano-sized precipitates are promisingly engineered in lightweight Al alloys to improve the high-temperature creep resistance that is increasingly required for rapid industrial development. However, the intrinsically-brittle eutectic phase is ready to fracture upon applied loading, which, dramatically reducing room-temperature ductility and fracture toughness, greatly hampers practical applications of the creep-resistant Al alloys. Here, through the combination of Sc microalloying with sub-rapid solidification, we observe the ductilization of Al11Ce3 eutectic phase in cast heat-resistant Al-Ce-Sc alloys due to the formation of atomic-scale compositional complexity. High-concentration Sc atoms are frozen within the Al11Ce3 intermetallic phase by the sub-rapid solidification, which then assemble into unusual atomic-scale compositional dipoles with the Sc atoms enriched at one pole and the Al atoms at the opposite during subsequent heat treatment. The dispersed Sc-Al compositional dipoles induce local lattice distortions that stimulate dislocation activities, as temporally and spatially visualized by in-situ neutron diffraction tensile test and microstructural characterizations. The unexpected plastic deformation triggered in Al11Ce3 improves the deformation compatibility between the eutectic phases, enabling the sub-rapidly-solidified Al-Ce-Sc alloy to reach a room-temperature tensile elongation 3 times and fracture toughness over 8 times of its counterpart derived from traditional solidification. In addition, the sub-rapidly-solidified Al-Ce-Sc alloy exhibits an excellent creep resistance at 300 °C, achieving a tensile creep stress threshold of ∼ 70 MPa. These findings provide new perspectives on the design of ductile intermetallic phases and the development of creep-resistant Al alloys with application-level ductility.

Metal aluminum is one of the ideal choices for the negative electrode material of the next generation energy storage batteries due to its high safety, low cost, and high theoretical capacity. However, the dendritic growth caused by the uneven electrode/electrolyte interface during the continuous metal electroplating/stripping process severely restricts its commercial application. In this work, an aluminum metal anode with the stable electrode/electrolyte interface has been prepared by a simple boiling water treatment followed by phosphoric acid immersion (BPA@Al anodes). The results indicated that the BPA@Al anode has the following advantages: (1) High ion conductivity accelerates the ion transport speed of the electrode/electrolyte interface; (2) High aluminum affinity reduces the activation energy of the reaction; (3) The uniform ion concentration distribution suppresses the growth of dendrites; (4) Fast charge transfer enables the battery to maintain better rate performance. Symmetrical cell using BPA@Al anodes maintains stable cycling for more than 7000 cycles at the current density of 10 mA & sdot;cm(-2). & sdot; cm(-2) . In addition, when the areal loading of the cathode material is 22.5 mg & sdot;cm- & sdot; cm- 2 , the full battery assembled with BPA@Al anode can stably cycle for more than 1400 h. The design principles and mechanism analysis in this study can provide theoretical basis and practical reference for exploring high safety and high stability aluminum anodes.

The electrolytic cellCell control systems, designed on the basis of cellCell voltage and line current, are becoming increasingly unsuitable for large aluminumAluminum electrolytic cellsCell. Instead, the design of the next generation electrolytic cellCell should be based on the anodeAnode. The accurate measurement of anodeAnode current is available by use of the fiber optic current sensor (FOCS). The employment of FOCS in aluminum reductionAluminum reduction cellsCell could be considered as a disruptive technological application. The measurement principle of FOCS is first introduced, and then the methodsMethod for online measurement of anodeAnode current in the aluminum reductionAluminum reduction cellCell are presented. The results showed that, FOCS could be used to provide a series of effective methodsMethod for achieving the digital, intelligent, and refined control of the aluminum reductionAluminum reduction cellCell based on the measurement results.

Rechargeable aluminum batteries (RAB) are a promising energy storage system with high safety, long cycle life, and low cost. However, the strong corrosiveness of chloroaluminate ionic liquid electrolytes (ILEs) severely limits the development of RAB separators. Herein, a nonsolvent-induced phase separation strategy was applied to fabricate the pPAN (poly(vinyl alcohol)-modified polyacrylonitrile) separator, which exhibits prominent chemical and electrochemical stability in ILEs. The pPAN separator, owing to its uniform pore size distribution and strong electronegativity with a zeta potential of about -10.20 mV, can effectively inhibit the growth of dendrites. Benefiting from the good ion conductivity (6.38 mS cm-1) and high ion migration number (0.133) of pPAN separator, the full cell with pPAN separator demonstrates stable operation for more than 500 cycles at 600 mA g-1, with a high capacity of 88.8 mAh g-1. When integrating into sodium-ion batteries, the pPAN separators also show an excellent electrochemical performance. This work provides a considerable approach for designing separators to address the issue of Al anode dendrite growth in RABs.

A gradient current collector (GCC) can encourage preferential Li metal deposition on the more lithiophilic/conductive bottom of 3D anodes, enhancing the reversibility of the battery. However, as the deposition proceeds, the reduction of lithophilicity/conductivity easily causes the disturbance of Li + flux. Herein, a brand‐new bicomponent‐bidirectional gradient current collector (BGCC) is proposed. The BGCC constructs slow‐release additives with reverse gradient distribution (SA gradient) based on GCC, allowing it to build a position‐responsive solid electrolyte interface layer. Additionally, as the deposition amount increases, the slow‐release additives will release more and present a stronger ability to regulate Li + flux, ensuring the anodereversibility under large deposition amounts conditions. Consequently, asymmetric cells can exhibit high reversibility with an average coulomb efficiency (CE) of 97.8% and sustain over 200 cycles using carbonate‐based electrolytes. The Li@BGCC||LiFePO 4 full cells hold a capacity retention of 94.8% over 400 cycles with thin Li. Notably, even at low temperatures, the Li@BGCC anodes can exhibit a CE as high as 98.46% and excellent capacity retention of 97.8% after 100 cycles paired with NCM811 cathodes. This strategy opens up a new direction for the development of 3D current collectors.