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Lignin-reinforced PVDF electrolyte for dendrite-free quasi-solid-state Li metal battery

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Rare Metals 2024年第3期43卷 1006-1016页

作者： Xin-Yang Chen Xue-Jie Gao han-Yan Wu Yu-Long liu xiao-Fei Yang {3.-Cang sun Center for Lignocellulosic Chemistry and Biomaterials College of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian116034China Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China School of Chemistry Northeast Normal UniversityChangchun130024China

Quasi-solid-state lithium metal batteries(QSSLMBs)assembled with polyvinylidene fluoride(PVDF)are a promising class of next-generation rechargeable batteries due to their safety,high energy density,and superior interfacial ***,PVDF has a series of inherent drawbacks such as low ionic conductivity,ease of crystallization,and hydrophobic character that leading to poor cell *** tackle these issues,a lignin-reinforced PVDF electrolyte is proposed in this work to solve these drawbacks of PVDF and enhance the comprehensive performance of *** lithophilic polar groups of lignin can promote uniform deposition of Li on the *** with the improved mechanical properties can efficiently prevent Li dendrites penetration through the *** addition,more active sites provided by lignin can also enhance Li^(+)transport and lead to a faster electrochemical reaction *** from the ingenious design,Li symmetric cells with 5%lignin-PVDF quasi-solid-state electrolyte can operate for 900 h at a high current density/capacity of 5 mA·cm^(-2)/5 mAh·cm^(-2),while shortcircuiting occurs after 56 h for the counterpart(pure PVDF).Moreover,a full cell of Li/5%lignin-PVDF/LFP cell demonstrates a high capacity of 96.2 mAh·g^(-1)after 2000 cycles at 10 *** work is expected to open up promising opportunities to develop other high-energy/power-density QSSLMBs.

关键词： Quasi-solid-state electrolyte Lignin PVDF Dendrite-free Li metal battery

Modified HDDR Process for Producing Anisotropic NdFeB Powders

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Journal of university of science and technology beijing 2001年第2期8卷 111-114页

作者： xubo liu, Yue Ming, yaofu xiao, Qi Zeng, Zhengyi Z{3.g, run Wang (Material science and engineering School, university of science and technology beijing, beijing 100083. china) (beijing Institute of Aeronautical Materials, beijing 100095, china) Univ Sci & Technol beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China Inst Aeronaut Mat Beijing 100095 Peoples R China

The effect of HDDR (hydrogenation-decomposition-desorption-recombination process) treating conditions on magnetic anisotropy of Nd13.ebalCo17B7Ga1Zr0.1 powders has been studied. It is found that increasing recombination temperature is effective for magnetic anisotropy formation, but at the cost of reducing the coercive force. The microstructure analysis (TEM) indicates that the NdFeB recombination nucleation takes place markedly during the transition range from decomposition stage to recombination stage, in which both temperature and H-2 pressure change sharply. In order to create a more stable treatment condition for recombination nucleation, a modified HDDR process is established in which the conventional continuous transition range is divided into several stages. The experimental results have proved that such a process can effectively enhance the remanence of the magnet powders with high certainty, while only cause a little reduction in coercivity.

关键词： HDDR anisotropy NdFeB

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZhanG JianMetallurgical engineering school.university of {3. and technology beijing, beijing 100083. china Metallurgical engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

A New Genetic Algorithm Based on Niche Technique and Local Search Method

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Journal of university of science and technology beijing 2001年第1期8卷 63-68页

作者： Jinwu Xu, Jiwen liu Mechanical engineering School,{3., beijing 100083. china Univ Sci & Technol beijing Sch Mech Engn Beijing 100083 Peoples R China

The genetic algorithm has been widely used in many fields as an easy robust global search and optimization method. In this paper, a new generic algorithm based on niche technique and local search method is presented under the consideration of inadequacies of the simple genetic algorithm. In order to prove the adaptability and validity of the improved genetic algorithm, optimization problems of multimodal functions with equal peaks, unequal peaks and complicated peak distribution are discussed. The simulation results show that compared to other niching methods, this improved genetic algorithm has obvious potential on many respects, such as convergence speed, solution accuracy, ability of global optimization, etc.

关键词： genetic algorithm (GA) niche technique local search method

Assessment of the apparent activation energies for gas/solid reactions—carbonate decomposition

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Journal of university of science and technology beijing 2003年第2期10卷 25-29页

作者： Jianhua liu and Jiayun ZhangMetallurgical engineering School,{3., beijing 100083. china Metall. Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The guidelines for assessing the apparent activation energies of gas/solidreactions have been proposed based on the experimental results from literatures. In CO_2 free inletgas flow, CaCO_3.decomposition between 950 and 1250 K with thin sample layer could be controlled bythe interfacial chemical reaction with apparent activation energy E = (215+-10) KJ/mol and E=(200+-10) kJ/mol at T = 813.to 1020 K, respectively. With relatively thick sample layer between 793.nd 1273.K, the CaCO_3.decomposition could be controlled by one or more steps involvingself-cooling, nucleation, intrinsic diffusion and heat transfer of gases, and E could vary between147 and 190 kJ/mol. In CO_2 containing inlet gas flow (5 percent-100 percent of CO_2), E wasdetermined to be varied from 949 to 2897 kJ/mol. For SrCO_3.and BaCO_3.decompositions controlled bythe interfacial chemical reaction, E was (213.-15) kJ/mol (1000-13.0K) and (3.5+-15) kJ/mol(1260-1400 K), respectively

关键词： assessment activation energy decomposition carbonate

Nonlinear Theory on Dynamic Controlling Interface Patterns DuringSolidification of a Dilute Binary Alloy

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 253-258页

作者： Zidong Wang hanqi Hu(Material science and engineering School, {3. of science and technology beijing, beijing 100083. china) Material science and engineering School University of Science and Technology Beijing Beijing 100083 China

In non-equilibrium nonlinear region, the nonlinear equations of time dependence of perturbation amplitude at the solid/liquidinterface during solidification of a dilute binary alloy are established on the base of assuming that there is local equilibrium at the solid/liquid interface and considering that curvature, temperature and composition at the solid/liquid interface which are related to the perturbation amplitude are nonlinear. As a result, patterns at the solid/liquid interface during solidification process, which is from nonsteadystate to steady state can be controlled by these nonlinear equations.

关键词： nonlinearity solidification, dilute binary alloy, dynamic control

Effects of silver powder particle size on the microstructure and properties of Ag-Yb_2O_3.electrical contact materials prepared by spark plasma sintering

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Rare Metals 2010年第4期29卷 366-370页

作者： CHEN xiaohua,JIA Chengchang,and liu Xiangbing School of Materials {3. and engineering,university of {3. and technology beijing,beijing 100083.china School of Materials science and engineering University of Science and Technology Beijing Beijing China

mg-Yb203.electrical contact materials were fabricated by spark plasma sintefing （SPS）. The effects of silver powder particle size on the microstructure and properties of the samples were investigated. The surface morphologies of the sintered samples were examined by optical microscope （OM）, and the fracture morphologies were observed by scanning electron microscopy （SEM）. The physical and mechanical properties such as density, electrical resistivity, microhardness, and tensile strength were also tested. The results show that the silver powder particle size has evident effects on the sintered materials. Comparing with coarse silver powder （5 ktm）, homogeneous and fme microstmcture was obtained by fine silver powder （_〈0.5-1am）. At the same time, the electrical conductivity, microhardness, and tensile strength of the sin- tered samples with fine silver powder were higher than those of the samples with coarse silver powder. However, silver powder particle size has little influence on the relative densities, which of all samples （both by free and coarse silver powders） is more than 95%. The fracture characteristics are ductile.

关键词： composites electrical contact materials spark plasma sintering particle size microstructure physical properties mechanical properties

Two-dimensional simulation on the rolling process of semi-solid 60Si2Mn by finite element method

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Journal of university of science and technology beijing 2002年第4期9卷 273-276页

作者： Renbo Song, Yonglin Kang, Xueping Ren, Hongbo Dong, and Jiwen wangmaterials science and engineering School,{3., beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The effect of various process variables on the law of metal flow for semi-solid rolling 60Si2Mn was studied by finite element method. Semi-solid 60Si2Mn can be described as compressible rigid visco-plastic porous material saturated with liquid. In terms of ther-mo-mechanical coupling condition, the distributions of stress, velocity and temperature were studied using software MARC. The simulation results show that the rigid visco-plastic model can accurately describe the semi-solid 60Si2Mn rolling process. The great deformation can achieve completely in view of low flow stress of semi-solid slurry.

关键词： finite-element analysis semi-solid thermo-mechanical coupling compressible rigid visco-plastic model rolling

Preparation of semi-solid AlSi7Mg alloy slurry with big capability

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Rare Metals 2010年第6期29卷 642-645页

作者： LI Sha and MAO Weimin School of Materials science and engineering,university of science and technology beijing,beijing 100083.china School of Materials science and engineering University of Science and Technology Beijing Beijing China

Semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak traveling-wave electromagnetic *** effects of pouring temperature and stirring power on the microstructure of AlSi7Mg alloy slurry were *** results show that the semi-solid AlSi7Mg alloy slurry of 5 kg can be *** new technology can save energy and make the pouring process *** the pouring temperature is decreased at a stirring power of 0.41 kW,the shape of primary α-Al grains gradually changes from dendritic-like to *** the alloy melt is poured at the temperature（63.°C） with a certain superheat,the pouring process becomes easier,and the spherical microstructure of AlSi7Mg alloy slurry can be prepared by the weak traveling-wave electromagnetic *** the pouring temperature is 63.°C,increasing the stirring power appropriately can result in better spherical primary α-Al grains,but if the stirring power is increased to a certain value（1.72 kW）,the shape of primary α-Al grains does not obviously improve when the stirring power is continually increased.

关键词： aluminum alloys metal forming semisolid slurry electromagnetic stirring microstructure