Main Electrode Research Articles

A solar thermoelectric system by temperature difference for efficient removal of chromium (VI) in water and soil

In this work, we designed and developed a facile solar thermoelectric generator (STEG)-based system and a new electrokinetic remediation (EKR) system, which consists of main electrodes and unenergized auxiliary electrodes. The prepared nanocomposite was investigated for the effectiveness of the STEG+PANI-CNT/GF system in remediating Cr-contaminated. Photothermal performance test were applied in order to examine this STEG could export a power density of 365.56mW/dm2 and output potential of 801mV at the temperature difference of 50 ℃. Thus the STEG could be used as the power to construct a Cr(VI) removal system using polyaniline (PANI) film/carbon nanotubes (CNT) modified graphite felt (GF) electrode (PANI-CNT/GF) as cathode and graphite rod as anode. The as-prepared STEG+PANI-CNT/GF system exhibited a significant Cr(VI) removal efficiency (96.2% in water) through electromigration, electro-adsorption and electroreduction. Moreover, a multi auxiliary electrodes (AEs) system (STEG+PANI-CNT/GF+AEs) with six PANI-CNT/GF auxiliary electrodes was constructed in remediating Cr(VI)-contaminated soil, showing Cr(VI) removal efficiency of 16.7-60.1% higher than that of STEG+PANI-CNT/GF. The PANI-CNT/GF auxiliary electrodes could bind Cr(VI) and adjust electric field distribution, contributing to adsorption and reduction of Cr(VI). Consequently, this work provides a promoting approach for heavy metals removal in future application.

Microstructure reconstruction via confined carbonization achieves highly available sodium ion diffusion channels in hard carbon

Hard carbon is considered as the main candidate negative electrode material for sodium-ion batteries (SIBs) due to its high stability and electrochemical performance. However, the complex carbon structure and composition of hard carbon are difficult to achieve precise control during the preparation process, which leads to difficulties in accurately determining the attribution of electrochemical behavior. Here, we propose a confined carbonization strategy to achieve microstructure reconstruction of hard carbon, characterized by the anchoring of polymers in the mesopores of porous carbon to generate ordered carbon structures at high temperatures. The stacking of ordered carbon on micropores in porous carbon achieves the transition from exposed pores to closed pores (nano cleithral pores). Through mechanism detection, it is found that the ordered carbon structure provides sub nanochannels for sodium ion migration, which contributes to high slope capacity. In addition, the nano cleithral pores are sites filled with sodium ions and provide high plateau capacity. Benefiting from theses available sodium ion transport channels, carbon materials have achieved a transition from surface-controlled process to diffusion-controlled process in the sodium storage process via confined carbonization. The as-prepared carbon delivers a superior capacity of 356.2 mAh g–1 (215.6 mAh g–1 for plateau capacity) at 20 mA g–1 with excellent rate and cycling performance. This work reveals the correlation between structure and electrochemical performance for carbon electrode, providing profound guidance for the precise preparation of high-performance carbon materials.

Influence of SF6/N2 Mixed Gas Pressure on the Arc Control Ability of the Main Electrode in the Trigger Gap

Abstract In the controllable self-recovery energy-absorbing apparatus of the Baihetan-Jiangsu Hybrid UHVDC Transmission Project, a 30%SF6/70%N2 mixed gas is employed as the insulating medium within the trigger gap switch. In order to mitigate surface erosion on the main electrode of the trigger gap switch, as well as the inner wall of the insulating sleeve, and to reduce the usage of SF6, an investigation into the arc control ability of the main electrode under different pressures of the mixed gas has been initiated. The motion characteristics of the arc within the gap have been simulated using a Magnetohydrodynamics (MHD) model, and the variation pattern of the main electrode’s arc control ability within the pressure range of 0.1MPa to 0.4MPa was obtained by analyzing the changes in the arc volume. The arc control ability of the main electrode is influenced by the differences in physical parameters of mixed gas at different pressures. Results indicate that the electrode’s arc control ability experiences an initial increase followed by a subsequent decrease with the rising pressure of 30%SF6/70%N2 mixed gas. Notably, within the pressure range of 0.1MPa to 0.4MPa, the main electrode exhibits the highest arc control ability when the pressure of the mixed gas is 0.3MPa.

Design, Fabrication, and Characterization of a Planar Three-Electrode Trigger Switch Based on Flexible Printed Circuit Process.

An exploding foil initiator system (EFIs) is essential in modern weaponry for its safety and reliability. As the main component of EFIs, the performance of the switch is critical to EFIs. In this study, a planar three-electrode trigger switch was designed and fabricated using the Flexible Printed Circuits (FPC) process. Subsequently, the performance of the FPC switch was tested. The results show that the self-breakdown voltage of the FPC switch is stable. In addition, an FPF switch with a 0.6 mm main electrode gap demonstrated consistency, with delay times below 31.75 ns, and a jitter ranging from 1.7 ns to 10.94 ns at 900 V to 1200 V, evidencing the FPC switches' reliability and uniform performance across various voltages. Compared to the Micro-Electro-Mechanical Systems (MEMS) switches of similar dimensions, the FPC switches achieved a faster high-current attainment with less inductance, showing a 5% reduction in loop inductance. The repetitive testing results demonstrate that the FPC switch maintains consistent output performance, with stable peak currents, peak current time, and delay time over 50 action cycles, highlighting its repeatability. The FPC switch was assembled with an EFI chip and capacitor into an integrated system, which was subsequently able to successfully detonate HNS-IV at 1000 V/0.22 μF, proving the FPC switch's potential in low inductance applications.

Time‐Dependent Deep Learning Manufacturing Process Model for Battery Electrode Microstructure Prediction

AbstractThe manufacturing process of Lithium‐ion battery electrodes directly affects the practical properties of the cells, such as their performance, durability, and safety. While computational physics‐based modeling has been proven as a very useful method to produce insights on the manufacturing properties interdependencies as well as the formation of electrode microstructures, their high computational costs prevent their direct utilization in electrode optimization loops. In this work, a novel time‐dependent deep learning (DL) model of the battery electrodes manufacturing process is reported, demonstrated for calendering of nickel manganese cobalt (NMC111) electrodes, and trained with time‐series data arising from physics‐based Discrete Element Method (DEM) simulations. The DL model predictions are validated by comparing evaluation metrics (e.g., mean square error (MSE) and R2 score) and electrode functional metrics (contact surface area, porosity, diffusivity, and tortuosity factor), showing very good accuracy with respect to the DEM simulations. The DL model can remarkably capture the elastic recovery of the electrode upon compression (spring‐back phenomenon) and the main 3D electrode microstructure features without using the functional descriptors for its training. Furthermore, the DL model has a significantly lower computational cost than the DEM simulations, paving the way toward quasi‐real‐time optimization loops of the 3D electrode architecture predicting the calendering conditions to adopt in order to obtain the desired electrode performance.

Spent graphite regeneration: Exploring diverse repairing manners with impurities-catalyzing effect towards high performance and low energy consumption

Spent battery recycling has received considerable attention because of its economic and environmental potential. A large amount of retired graphite has been produced as the main electrode material, accompanied by a detailed exploration of the repair mechanism. However, they still suffer from unclear repair mechanisms and physicochemical evolution. In this study, spent graphite was repaired employing three methodologies: pickling-sintering, pyrogenic-recovery, and high-temperature sintering. Owing to the catalytic effect of the metal-based impurities and temperature control, the as-obtained samples displayed an ordered transformation, including the interlayer distance, crystalline degree, and grain size. As anodes of lithium ions batteries, the capacity of repaired samples reached up to 310 mA h g−1 above after 300 loops at 1.0 C, similar to that of commercial graphite. Meanwhile, benefitting from the effective assembly of carbon atoms in internal structure of graphite at >1400 °C, their initial coulombic efficiency were >87%. Even at 2.0 C, the capacity of samples remained approximately 244 mA h g−1 after 500 cycles. Detailed electrochemical and kinetic analyses revealed that a low temperature enhanced the isotropy, thereby enhancing the rate properties. Further, economic and environmental analyses revealed that the revenue obtained through suitable pyrogenic-recovering manners was approximately the largest value (5500 $ t−1). Thus, this study is expected to clarify the in-depth effect of different repair methods on the traits of graphite, while offering all-round evaluations of repaired graphite.

(Invited) On Degradation Mechanisms of Ni-YSZ Fuel Electrodes in Solid Oxide Cells

The solid oxide cell (SOC) is reversible. It has about equally good performance both in solid oxide fuel cell (SOFC) and in solid oxide electrolyzer cell (SOEC) mode. The classical Ni-YSZ cermet SOC fuel electrode has an excellent initial performance provided that it has a good structure in terms of particle size of both Ni and YSZ, and a suitable porosity with sufficient contact between Ni-Ni, YSZ-Ni, YSZ-YSZ particles, and in absence of certain impurities such as silica and sulfur. The essential entity of the Ni-YSZ electrode is the length of the three phase boundary (3pb) between the three phases of Ni electron conductor, YSZ oxide ion conductor, and H2-H2O gas, which have electronic contact to the main Ni electrode, ionic contact to the bulk YSZ electrolyte, and access to the the main gas atmosphere, respectively.Nano-particular Ni is an excellent electrocatalyst for the reduction of H2O to H2 + O2- and for the oxidation. It seems that it is generally accepted that at operation temperatures (above 650 °C and above) the initial nano-sized Ni particles, which are in electric contact with each other, will over time continue to sinter into larger and larger Ni particles until all the Ni has become one dense body or the growth of the Ni particles has been blocked by particles of another phase like YSZ. Thus, the relative high mobility of Ni continues to pose a problem towards the lifetime of a highly functional Ni-YSZ electrode.A most serious type of degradation of Ni-YSZ electrodes in solid oxide electrolysis cells (SOEC) seems to be the one coupled to Ni-migration, which is regarded as an important obstacle for the commercialization of SOEC. Post mortem scanning electron microscopy investigations of the degraded Ni-YSZ electrode reveal that a thin (up to 3 – 5 µm) zone of the original nano-structured active Ni-YSZ cathode has been significantly been depleted in Ni. This degradation is clearly driven by the electrochemical polarization of the Ni-YSZ electrode [1], but the mechanism is highly discussed. Several researchers have the hypothesis that the Ni depletion is a result of Ni migration in a gradient in Ni/YSZ interface energy, see e.g. [2,3]. However, a review of relevant literature points out that this hypothesis cannot explain several reported clear experimental results, whereas our hypothesis based on Ni+ ions from Ni particles, which have lost electrochemical contact, migrate as NiOH across the YSZ particles to new active 3pbs formed further away from the bulk electrolyte. This hypothesis may qualitatively explain all reported results from steam electrolysis cells and H2 fuel cells so far [1]. However, our hypothesis does not directly explain the similar migration of Ni away from the YSZ bulk electrolyte in case of CO2 electrolysis.Therefore, a revision of our hypothesis will be presented. The essential change is simply to propose that it is the Ni+-ion that migrates in the YSZ-surface layer as either NiOH in case of steam electrolysis, or as “Ni2CO3” in case of CO2 electrolysis. A monolayer of “Ni2CO3” on a YSZ surface is not assumed to be any kind of crystalline Ni2CO3, but rather a layer of adsorbed Ni+ and “CO3 1-“ in which CO3 2- has one of its oxygen atoms incorporated into the YSZ surface crystalline structure which is formed by reaction between CO2 from gas and an unsaturated surface oxygen with a “dangling” electron with similarity to CO2 reduction on ceria [4]. Furthermore, the possible role of SiO2 impurities in the loss of contact between Ni and YSZ at negatively polarized Ni will be presented as another revision of the hypothesis together with further new details.References M.B. Mogensen et al., Fuel Cells, (2021), 1–15; DOI: 10.1002/fuce.202100072, and references therein.M. Trini et al., Acta Materialia, 212 (2021) 116887; DOI: 10.1016/j.actamat.2021.116887.L. Rorato et al., J. Electrochem. Soc., 170 (2023) 034504, DOI: 10.1149/1945-7111/acc1a3, and references therein.E.M. Sala et al., Phys. Chem. Chem. Phys. (2023), DOI: 10.1039/d2cp05157e.

Integrating natural tourmaline with energy conversion ability to magnetically assembled electrode: Boosted electrochemical oxidation wastewater treatment performance

Novel anodes are desirable in the development of electrochemical oxidation wastewater treatment (EOWT). Magnetically assembled electrode (MAE) is a novel modular electrode format that physically adsorbs magnetic particles (auxiliary electrodes, AEs) onto the main electrode (ME) by magnetic force which realizes an effective and sustainable EWOT process but puts a new requirement on AEs polarization. Therefore, tourmaline (Tml), a natural mineral with ferroelectricity, pyroelectricity, and piezoelectricity, was introduced into the MAE in this study. Tml particles were expected to utilize waste heat or mechanical energies in electrolysis (e.g., Joule heat, bubble strike) and give extra electricity to the stacked AEs (Fe3O4/Sb-SnO2 granules herein) to fully active MAE. Tml’s effects were investigated via different MEs (Ti/IrO2-Ta2O5, graphite, Ti/Sb-SnO2), different wastewater, different Tml sizes, loading amounts, and different conditions (e.g., current density). Results show that all these conditions could affect the buffering of Acid red G degradation, Tml could offer a 10∼40% buff. Medium Tml size and loading as well as low or medium current density (e.g., 2 mA·cm−2 or 20 mA·cm−2) are appropriate. For real wastewater degradation, Tml facilitates macromolecule destruction. This study may start a new application route of abundant natural energy-converting materials in the EOWT area.

The Mitigation of Interference on Underground Power Lines Caused by the HVDC Electrode

High Voltage Direct Current power links are usually designed to adopt, on a continuous basis or during emergency operations, two grounding plants using the soil or seawater as a link–current return path. Such DCs flowing into the ground can cause problems, of which one of the most important is the increased risk of the corrosion of metallic structures in the area. Normally, the simplest mitigation technique is to keep an adequate distance between the main grounding plants and any metallic structure that can be corroded. Normally, such distances are not less than 5 km. However, there are situations where this approach cannot be applied, for example due to geographical constraints. In this paper, we describe and analyze the behavior of a mitigation technique that can be adopted when the HV pole cable is laid closer than the recommended distance to the main ground electrode. This paper is focused on the minimization of deleterious effects on the cable’s metallic sheath and its earthing points, distributed along it by means of sheath segmentation. The suggested approach appears well-suited to substantially diminishing the current flowing through the sheath of an HVDC power cable. In the segmented scenario, the sheath’s power dissipation is less than one-hundredth of that in the typical continuous configuration.

Removal of E133 brilliant blue dye from artificial wastewater by electrocoagulation using cans waste as electrodes

AbstractSolid‐waste management, particularly of aluminum (Al), is a challenge that is being confronted around the world. Therefore, it is valuable to explore methods that can minimize the exploitation of natural assets, such as recycling. In this study, using hazardous Al waste as the main electrodes in the electrocoagulation (EC) process for dye removal from wastewater was discussed. The EC process is considered to be one of the most efficient, promising, and cost‐effective ways of handling various toxic effluents. The effect of current density (10, 20, and 30 mA/cm2), electrolyte concentration (1 and 2 g/L), and initial concentration of Brilliant Blue dye (15 and 30 mg/L) on the efficiency of the EC process were examined in this study. The results show that removal efficiency increased with current density and sodium chloride (NaCl) concentration and decreased with initial dye concentration. The electrical power and electrodes consumed increased with an increase in current density and decreased notably with increased NaCl. The optimum current density and amount of NaCl were 20 mA/cm2 and 2 g/L, respectively to attain highest values of E133 brilliant blue dye removal. The EC process was examined using adsorption isotherms and kinetics models. Those results showed that the Langmuir isotherm matched the experimental data. Furthermore, the experimental data were followed the Elovich model kinetics.

Simple Method for Enhancing Performance of the Bacterial Cellulose-Based Triboelectric Nanogenerator by Adding Conductive Interlayer

Surface charge density is a key factor that greatly enhances the performance of a natural-based triboelectric nanogenerator (TENG), which is essential for future sustainable sensing and harvesting devices. This work introduced a conductive interlayer between a main frictional layer and electrode. This approach can suppress the charge recombination rate and improve the amount of charges produced during the triboelectrification process. Bacterial cellulose (BC) film was selected as a main frictional layer for the TENG. A conductive nanomaterial, i.e. silver flake, was incorporated into the BC film as an intermediate layer for enhancing TENG performance. As firstly reported, the maximum electrical outputs for the multi-layer BC structure could be found when using silver flake/BC composite (ratio 1:5) as an intermediate layer, which has 122 V and 8.2 µA of output voltage and current, respectively. This is higher than the output voltage and current of a single layer BC TENG by approximately 3 and 8 times, respectively. The maximum output power of ∼440 µW is achieved by connecting with a load resistor of ∼10 MΩ. This demonstrates an efficient strategy for designing a high performance energy harvester by adding an intermediate layer for the target of practical purposes in sustainable systems.

Large-Area Inkjet-Printed Flexible Hybrid Electrodes with Photonic Sintered Silver Grids/High Conductive Polymer.

The field of printed organic electronics has not only made flexible devices accessible but also allows the production process toward a high throughput industrial scale. The current research involves the inkjet-printing of an indium tin oxide-free large-area flexible hybrid electrode compose of a high conductivity organic layer (PEDOT: PSS) as a main electrode and inorganic silver nanoparticles-based grid/film for the auxiliary electrode. The current bottleneck in the roll-to-roll production of printed electronics is the time required for the conductive inks to dry and sinter. Flash sintering is used to dry nano-silver conductive ink to 77.6mΩ□-1 sheet resistance in <20ms, the quickest annealing procedure, without damaging flexible substrates. Flexible organic light-emitting diodes (OLEDs) are created with a large active area (500mm2 ) to demonstrate the efficacy of the flexible hybrid electrodes and the excellent bending stability (4mm bending radius) of OLEDs. Maximum current efficiency of 19.58cdA-1 and a maximum luminescence of 8708cdm-2 at a low turn-on voltage of 3.1V for the small-area (16mm2 ) OLEDs are achieved. This method is promising for reducing indium consumption and paving the way for creating new high throughout hybrid electrodes for large-area flexible printed electronics.

Removal of diazinon from aqueous solutions using 3D electrochemical system including a nanocomposite of microbial cellulose/nanomagnetite

In this study, with the aim of improving of the diazinon removal efficiency, a 3D electrochemical system was provided including microbial cellulose/Fe3O4 (MC/Fe3O4) nanocomposite. The MC/Fe3O4 nanocomposite was utilized for the activation of persulfate (PS) in the diazinon decomposition process. The characterization of the MC/Fe3O4 nanocomposite was determined by FE-SEM, FT-IR, XRD and TGA analysis. The operating variables including initial pH, NaCl concentration, PS concentration, initial diazinon concentration, current density and time were investigated. The proposed 3D electrochemical system in the optimal conditions of 10 mg/L initial diazinon concentration, pH 3, 0.2 g/L NaCl, 0.07 mmol/L PS, 3.54 mA/cm2 current density and energy consumption of 12.61 kWh/m3 during 60 min reached to the complete removal of diazinon and 84.4 % TOC removal. According to the obtained results, the MC/Fe3O4 nanocomposite has the high efficiency of diazinon and TOC removal, as well as the consumption of NaCl, PS and lower energy in a shorter period of time compared to general electrochemical processes. Therefore, the reactions provide not only on the surface of the main electrodes but also on the surface of the particle electrode. It can improve the performance of electroabsorption and electrocatalysis in the chemical electrooxidation system.

ELIMINATION OF CRACKS IN METAL PARTS

One of the most versatile and effective methods of restoring parts is the method of electric spark processing. On the basis of this method, a technological process was developed that allows to obtain a thick-layer coating of increased continuity. The use of electric spark processing in the restoration of parts is an urgent task of eliminating cracks in metal parts of machines. (Research purpose) The research purpose is eliminating cracks in metal parts of machines by the electric spark processing to obtain sealed coatings. (Materials and methods) BRKMTS3-1 bronze was chosen as the main electrodes, M1 copper was chosen for the reflow electrode for experimental work to eliminate cracks by electric spark treatment. It was determined that the process of eliminating cracks took place in several cycles. (Results and discussion) Experiments have shown that, using only the reception of a thick-layer electric spark coating, it is possible to close a crack up to 1.5 millimeters wide inclusive, but it is practically impossible to obtain a sealed coating. It was established as a result of studies of the effect of surface plastic treatment that the average microhardness of the coating, untreated by the method of surface plastic deformation, was 250 according to Vickers. The maximum microhardness of the sample treated by the method of surface plastic deformation at a depth of 0.05 millimeters was more than 500 Vickers. (Conclusions) The experiments carried out to eliminate cracks have shown that using only the reception of a thick-walled electric spark coating, it is easy to close a crack up to 1.5 millimeters wide inclusive, but it is almost impossible to obtain a sealed coating, since it has significant porosity. For those cases where the tightness of the seam is mandatory, additional processing by the method of surface plastic deformation is necessary.

Research progress of transition metal compounds and composites in the field of supercapacitors

Supercapacitors are widely used in the field of energy storage because of their high power density and good cycle stability. The energy storage mechanism of different electrode materials is different, and the corresponding supercapacitors are also obviously different. In recent years, transition metallic compounds with high energy density and capacitance have attracted extensive attention. In this paper, the energy storage principles and research results of three main transition metal-based electrode materials (transition metal oxide (TMOs), Layered double hydroxides (LDHs) and transition metal sulfide (TMDs)) and the research progress of their composites are reviewed, and the future of transition metal-based electrode materials is prospected.

Paper-based electrochemical biosensors for the diagnosis of viral diseases.

Paper-based electrochemical analytical devices (ePADs) have gained significant interest as promising analytical units in recent years because they can be fabricated in simple ways, are low-cost, portable, and disposable platforms that can be applied in various fields. In this sense, paper-based electrochemical biosensors are attractive analytical devices since they can promote diagnose several diseases and potentially allow decentralized analysis. Electrochemical biosensors are versatile, as the measured signal can be improved by usingmainly molecular technologies andnanomaterials to attach biomolecules, resulting in an increase in their sensitivity and selectivity. Additionally, they can be implementedin microfluidic devices that drive and control the flow without external pumping and store reagents, and improve the mass transport of analytes, increasing sensor sensitivity. In this review, we focus on the recent developments in electrochemical paper-based devices for viruses' detection, including COVID-19, Dengue, Zika, Hepatitis, Ebola, AIDS, and Influenza, among others, which have caused impacts on people's health, especially in places with scarce resources. Also, we discuss the advantages and disadvantages of the main electrode's fabrication methods, device designs, and biomolecule immobilization strategies. Finally, the perspectives and challenges that need to be overcome to further advance paper-based electrochemical biosensors' applications are critically presented.

A Flexible 8-in-1 Microsensor Embedded in Proton Battery Stack for Real-Time Microscopic Measurements

According to the latest literature, it is difficult to measure the multiple important physical parameters inside a proton battery stack accurately and simultaneously. The present bottleneck is external or single measurements, and the multiple important physical parameters (oxygen, clamping pressure, hydrogen, voltage, current, temperature, flow, and humidity) are interrelated, and have a significant impact on the performance, life, and safety of the proton battery stack. Therefore, this study used micro-electro-mechanical systems (MEMS) technology to develop a micro oxygen sensor and a micro clamping pressure sensor, which were integrated into the 6-in-1 microsensor developed by this research team. In order to improve the output and operability of microsensors, an incremental mask was redesigned to integrate the back end of the microsensor in combination with a flexible printed circuit. Consequently, a flexible 8-in-1 (oxygen, clamping pressure, hydrogen, voltage, current, temperature, flow, and humidity) microsensor was developed and embedded in a proton battery stack for real-time microscopic measurement. Multiple micro-electro-mechanical systems technologies were used many times in the process of developing the flexible 8-in-1 microsensor in this study, including physical vapor deposition (PVD), lithography, lift-off, and wet etching. The substrate was a 50 μm-thick polyimide (PI) film, characterized by good tensile strength, high temperature resistance, and chemical resistance. The microsensor electrode used Au as the main electrode and Ti as the adhesion layer.

Analysis of the Influence of the Spark Plug on Exhaust Gas Composition

This paper analyses the influence of the type of electrode in a spark plug on exhaust gas emission. The objects of the research were the following vehicles of different years of production: the Volkswagen Beetle 1300, the Honda Nighthawk 650, the BMW e46 318i, the Hyundai i10, and the Audi A4 B6. The vehicles were powered by petrol and LPG. Spark plugs were selected for the vehicles, with different kinds of construction for the main electrodes and different numbers of poles but with similar heat values. A comparative analysis of the composition of the exhaust gas mixture was performed, depending on the set of spark plugs used. The amount of CO, HC, CO2, and O2 emissions was analysed. The results were compared with the applicable exhaust gas emission standards. Both in the case of E5 95 petrol and LPG gas, lower exhaust gas emissions were observed when iridium spark plugs were used.

Development of a High Power Density In-Wheel Motor Using Halbach Array Magnets

In this study, a direct drive in-wheel system is proposed as a high power density system for reducing the intermediate parts, such as a speed reducer by increasing the torque. We propose a design strategy to show that multipolarization and the improvement of the gap magnetic flux density can effectively increase the power density. A Halbach array magnet rotor that combines the main electrode magnets and spoke magnets with the core is adopted as a technique for improving the gap magnetic flux density. We compare the Halbach array type rotor to the conventional SPM type rotor by using both of magnetic circuit calculation and FEM analysis. Moreover, the actual sized in-wheel motor prototype with the developed Halbach array magnet rotor is fabricated and measures the no-load induced back EMF. The measured no-load induced back EMF agrees well with the analyzed waveform.

Research on optimization test of electrode material in desulfurization wastewater purification system of coal-fired power plant

The traditional coal-fired power plant wastewater treatment technology is faced with the problems of complex system, high operating cost, easy scaling and corrosion, etc. Therefore, coal-fired power plants need to adopt an integrated multi-functional coupling system, taking into account the desalination, anti-scaling, etc. function to remove pollutants from wastewater. Electro-adsorption technology is a technology that can realize water purification and water desalination. It is a new type of water treatment technology. It can effectively remove impurity ions in water without scaling under the premise of low energy consumption. In this paper, the development history of electrosorption theory, the principle of electrosorption, the main points of electric double layer theory, the structure of electrosorption and its working process are reviewed. Several main electrode materials and their advantages and disadvantages are introduced in this paper. Based on the increasingly stringent environmental protection requirements, electro-adsorption technology is expected to be widely used in the power industry due to its advantages of low energy consumption, low cost, and no secondary pollution.