Optimizing Average Electric Power During the Charging of Lithium-Ion Batteries Through the Taguchi Method

In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach.

Mechanical and Electrical Properties of Some Sn-Zn Based Lead-Free Quinary Alloys

Although there are many lead-free soldering alloys on the market, none of them have ideal qualities. The researchers are combining binary alloys with a variety of additional materials to create the soldering alloys’ features. The eutectic Sn-9Zn alloy is among them. This paper investigated the mechanical and electrical properties of Sn-9Zn-x (Ag, Cu, Sb);{x = 0.2, 0.4, and 0.6} lead-free solder alloys. The mechanical properties such as elastic modulus, ultimate tensile strength (UTS), yield strength (YS), and ductility were examined at the strain rates in a range from 4.17 10−3 s−1 to 208.5 10−3 s−1 at room temperature. It is found that increasing the content of the alloying elements and strain rate increases the elastic modulus, ultimate tensile strength, and yield strength while the ductility decreases. The electrical conductivity of the alloys is found to be a little smaller than that of the Sn-9Zn eutectic alloy.

Effect of heating rate on the densification of NdFeB alloys sintered by an electric field

This study introduces a novel method of electric field sintering for preparing NdFeB magnets. NdFeB alloy compacts were all sintered by electric fields for 8 min at 1000~C with different preset heating rates. The characteristics of electric field sintering and the effects of heating rate on the sintering densification of NdFeB alloys were also studied. It is found that electric field sintering is a new non-pressure rapid sintering method for preparing NdFeB magnets with fine grains at a relatively lower sintering temperature and in a shorter sintering time. Using this method, the sintering temperature and process of the compacts can be controlled accurately. When the preset heating rate in- creasing from 5 to 2000~C/s the densification of NdFeB sintered compacts gradHally improves. As the preset heating rate is 2000C/s, Nd-rich phases are small, dispersed and uniformly distributed in the sintered compact, and the magnet has a better microstructure than that made by conventional vacuum sintering. Also, the maximum energy product of the sintered magnet reaches 95% of conventionally vacuum sintered magnets.

Effects of the Shading Rate on the Electrical Parameters of CIGS-Based Solar Modules

The aim of this article is to study the effects of the shading rate on the electrical performance parameters of CIGS PV modules. The study concerns a new flexible CIGS type photovoltaic module with a power of 90 W, manufactured by the company Shenzhen Shine Solar Co., Ltd. This module, reference SN-CIGS90, is tested under the initial conditions to ensure its correct operation and to determine the initial values of the electrical parameters before shading. After this characterization test, the module is exposed under the actual operating conditions of the Renewable Energies Study and Research Center (CERER), located in Dakar, then 4 types of shading are performed with the same mask: partial shading 25% partial shading, 50% partial shading, 75% partial shading, and 100% full shading. The variation rates obtained on the experimental values of the 4 types of shading carried out determine that the shading phenomenon constitutes a factor that influences negatively on the electrical parameters of a CIGS-based PV module. Indeed, for 25% of the surface of the shaded module, there is a reduction of 58.139% of the maximum power and of 60.507% of the efficiency and for shading of 100%, the module loses 84.436% of its maximum power and 84.135% of its performance.

Electrical treeing behaviors in silicone rubber under an impulse voltage considering high temperature

In this paper,work was conducted to reveal electrical tree behaviors（initiation and propagation）of silicone rubber（SIR） under an impulse voltage with high temperature.Impulse frequencies ranging from 10 Hz to 1 k Hz were applied and the temperature was controlled between 30 °C and 90 °C.Experimental results show that tree initiation voltage decreases with increasing pulse frequency,and the descending amplitude is different in different frequency bands.As the pulse frequency increases,more frequent partial discharges occur in the channel,increasing the tree growth rate and the final shape intensity.As for temperature,the initiation voltage decreases and the tree shape becomes denser as the temperature gets higher.Based on differential scanning calorimetry results,we believe that partial segment relaxation of SIR at high temperature leads to a decrease in the initiation voltage.However,the tree growth rate decreases with increasing temperature.Carbonization deposition in the channel under high temperature was observed under microscope and proven by Raman analysis.Different tree growth models considering tree channel characteristics are proposed.It is believed that increasing the conductivity in the tree channel restrains the partial discharge,holding back the tree growth at high temperature.

Secondary Activation of Commercial Activated Carbon and its Application in Electric Double Layer Capacitor

The cheap commercial activated carbon (AC) was improved through the secondary activation under steam in the presence of FeCl2 catalyst in the temperature range of 800-950℃ and its application in electric double layer capacitors (EDLCs) with organic electrolyte was studied. The re-activation of AC results in the increases in both specific capacitance and high rate capability of EDLCs. For AC treated under optimized conditions, its discharge specific capacitance increases up to 55.65 F/g, an increase of about 33% as compared to the original AC, and the high rate capability was increased significantly. The good performances of EDLC with improved AC were correlated to the increasing mesoporous ratio.

Aircraft Electric Anti-skid Braking System Based on Fuzzy-PID Controller with Parameter Self-adjustment Feature

The principle of electric braking system is analyzed and an anti-skid braking system based on the slip rate control is proposed.The fuzzy-PID controller with parameter self-adjustment feature is designed for the anti-skid braking system.The dynamic model of aircraft ground braking is established in the simulation environment of MATLAB/SIMULINK,and simulation results of dry runway and wet runway are presented.The results show that the fuzzy-PID controller with parameter self-adjustment feature for the electric anti-skid braking system keeps working in the state of stability and the brake efficiencies are increased to 93%on dry runway and 82%on wet runway respectively.

Improving energy utilization efficiency of electrical discharge milling in titanium alloys machining

Electrical discharge milling(ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energy utilization efficiency of ED-milling process, unstable arc discharge and stable arc discharge combined with normal discharge were implemented for material removal by adjusting servo control strategy. The influence of electrode rotating speed and dielectric flushing pressure on machining performance was investigated by experiments. It was found that the rotating of electrode could move the position of discharge plasma channel, and high pressure flushing could wash melted debris out the discharge gap effectively. Both electrode rotating motion and high pressure flushing are contributed to the improvement of machining efficiency.

Effect of electric boundary conditions on crack propagation in ferroelectric ceramics

In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga Njiwa et al.（Eng. Fract. Mech., 2006）.

Estimate of China's energy carbon emissions peak and analysis on electric power carbon emissions

China's energy carbon emissions are projected to peak in 2030 with approximately 110%of its 2020 level under the following conditions:1)China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2030;2)coal's share of the energy consumption is 61%in 2020 and55%in 2030;3)non-fossil energy's share increases from 15%in 2020 to 20%in 2030;4)through 2030,China's GDP grows at an average annual rate of 6%;5)the annual energy consumption elasticity coefficient is 0.30 in average;and 6)the annual growth rate of energy consumption steadily reduces to within 1%.China's electricity generating capacity would be 1,990 GW,with 8,600 TW h of power generation output in 2020.Of that output 66%would be from coal,5%from gas,and 29%from non-fossil energy.By 2030,electricity generating capacity would reach3,170 GW with 11,900 TW h of power generation output.Of that output,56%would be from coal,6%from gas,and 37%from non-fossil energy.From 2020 to 2030,CO2emissions from electric power would relatively fall by 0.2 Gt due to lower coal consumption,and relatively fall by nearly 0.3 Gt with the installation of more coal-fired cogeneration units.During 2020e2030,the portion of carbon emissions from electric power in China's energy consumption is projected to increase by 3.4 percentage points.Although the carbon emissions from electric power would keep increasing to 118%of the 2020 level in 2030,the electric power industry would continue to play a decisive role in achieving the goal of increase in non-fossil energy use.This study proposes countermeasures and recommendations to control carbon emissions peak,including energy system optimization,green-coal-fired electricity generation,and demand side management.

Effects of electric-field treatment on a Ni-base superalloy

The effects of electric-field treatment on the microstructure and deformation behavior of a nickel-base superalloy were summarized.The results show that the electric-field treatment increases the ductility of the superalloy but has no evident influence on its static strength at both room and elevated temperatures,while,the strength increases but elongation changes weekly with the increasing tensile strain rate.It is found that the direction of microcrack propagation can be changed by the presence of the annealing twins during the tensile deformation,and it causes the increasing of the plastic deformation energy and delay of the fracture,which is considered as the reason for the increasing the ductility.

EFFECT OF A WEAK LONGITUDINAL ELECTRIC FIELD ON WHISTLER WAVES

The effect of a longitudinal electric field on whistler waves is studied based onkinetic theory.A local Maxwellian distribution is taken as stationary distribution function ofelectrons which departs from thermodynamic equilibrium due to the applied electric field.Thedielectric tensor is derived by integrating along orbit of the particle in the unperturbed field.Dispersion relation and growth rate are analysed from Hermitian and anti-Hermitian parts ofthis tensor respectively.It is found that the waves are growing when the angle between the wavevector and the electric field is in range of θ【2θ_c, otherwise the whistler waves are damping.Thegrowth rate increases with wave frequency and decreases with the angle between the wave vectorand the applied field.In the case of ω_e(?)Ω the maximum of growth rate,which is at θ=O_l isproportional to the plasma density and anti-proportional to the magnetic field.Some computedresults for parameters at top of the F layer are given.

Electric Wheelchair Control System Using Brain-Computer Interface Based on Alpha-Wave Blocking

A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram(EEG) when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject's triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min.

Effect of Electrode Materials on Electric Discharge Machining of 316 L and 17 - 4 PH Stainless Steels

Electric Discharge Machining (EDM) is one of the most efficiently employed non-traditional machining processes for cutting hard-to-cut materials, to geometrically complex shapes that are difficult to machine by conventional machines. In the present work, an experimental investigation has been carried out to study the effect of pulsed current on material removal rate, electrode wear, surface roughness and diameteral overcut in corrosion resistant stainless steels viz., 316 L and 17-4 PH. The materials used for the work were machined with different electrode materials such as copper, copper-tungsten and graphite. It is observed that the output parameters such as material removal rate, electrode wear and surface roughness of EDM increase with increase in pulsed current. The results reveal that high material removal rate have been achieved with copper electrode whereas copper-tungsten yielded lower electrode wear, smooth surface finish and good dimensional accuracy.

Contrast Test of Precision Electric Mist Duster and Electric Sprayer

[Objectives]The paper was to compare and verify the operation performance of precision electric mist duster and electric sprayer,and to select the optimum plant protection equipment suitable for greenhouse application.[Methods]Agents were sprayed by precision electric mist duster and electric sprayer to control tomato downy mildew in greenhouse,and the control effect and pesticide utilization rate were compared.[Results]Compared with electric sprayer,precision electric mist duster improved the pesticide utilization rate by 31.7%,improved the spray efficiency by 20 times,and increased the control effect by 13.2%.[Conclusions]The study provides technical support for the popularization and application of precision electric mist duster in greenhouse and other facilities cultivation.

基于PLC技术的联合收割机电气控制系统设计

以联合收割机电气控制系统为研究对象,利用可编程控制器(PLC)对联合收割机电气控制系统进行改进,以提高联合收割机运行效率和可靠性。通过对联合收割机的工作原理和液压作动系统进行分析,基于可编程控制器(PLC)进行联合收割机电气系统整体设计,并对电气系统的运行效果进行测试分析。试验结果表明:系统运行可靠,能够获得良好的收割效果,可将收割损失率控制在2%以内,验证了系统运行过程稳定性。