摘要
由于电阻层析成像(electrical resistancetomography,ERT)技术具有非扰动、无辐射、可视化等优点,本文基于该技术提出了一套能够实现锂离子电池阴极浆料粒子分布特性的可视化在线监测系统。ERT监测系统包括阻抗分析仪(impedance analyzer,IM3570,HIOKI)、计算机(PC)、多路复用器(34970A,Agilent)和8电极传感器。在实验中,搅拌器搅拌速度为720r/min,搅拌时间在360s以内,激励电流的频率为f=1kHz,幅值为1mA。电流输入采用相间激励法,从而获得20组测量电压数据。另外,基于总变差(total variation,TV)正则化的PD-IPM算法重构了ERT图像,同时,定义了电导率平均值σ—ave和均方差s来定量分析ERT重构图像。此外,为了定性和定量验证ERT测量系统的可行性,分别采用了扫描电子显微镜(scanning electron microscopy,SEM)方法和电阻抗谱(electrical impedance spectroscopy,EIS)方法。对比结果表明,①ERT重构图像和SEM表观形貌图像基本一致,当搅拌时间t<120s时,SEM表观形貌图像中粒子凝聚较为严重,ERT重构图像中颜色变化明显;当t≥120s时,SEM表观形貌图像中粒子趋于分散,ERT重构图像中颜色呈现较为单一的橙色。②EIS中的电阻Z′和电抗Z″变化的变化量与σ—ave和s的变化量相符合,并且阴极浆料的电化学特性能够与ERT重构图像相互对应。因此,基于ERT的锂离子电池阴极浆料分布特性的动态可视化监测系统具有可行性,能够应用于阴极浆料实际工程制备的在线动态监测。
Electrical resistance tomography(ERT)technology has the advantages of non-disturbance,non-radiation and visualization.Based on this technology,a visual on-line monitoring system was proposed in the present study,which can monitor the particle distribution of LIB cathode slurry.The ERT monitoring system included an impedance analyzer(IM3570,HIOKI),a computer(PC),a multiplexer(34970A,Agilent)and an 8-electrode sensor.In the experiment,the stirring speed of the stirrer was 720r/min,the stirring time was shorter than 360s,the frequency of excitation current was f=1kHz,and the amplitude was 1mA.Phase-to-phase excitation method was adopted for current input,and 20 sets of measured voltage data were obtained.In addition,PD-IPM algorithm based on total variation(TV)regularization reconstructed ERT image,and defined averageσ-ave and standard deviation s of conductivity to quantitatively analyze ERT reconstructed image.In order to qualitatively and quantitatively verify the feasibility of ERT measurement system,scanning electron microscopy(SEM)method and electrical impedance spectroscopy(EIS)method were used respectively.Comparison results showed that①ERT reconstructed image was basically consistent with SEM apparent topography image.When the stirring time t was less than 120s,the agglomeration of particles in SEM apparent morphology image was serious,and the color change in ERT reconstructed image was obvious.When t≥120s,the particles tended to disperse in the SEM image,and the color of ERT reconstructed image was single orange.And②The variation of resistance Z′and reactance Z of EIS was consistent with the variation of σ_(ave) and s,and the electrochemical characteristics of cathode paste could correspond to ERT reconstructed image.Therefore,the ERT-based dynamic visualization monitoring system of cathode slurry distribution characteristics was feasible and could be applied to online dynamic monitoring of cathode slurry preparation in practical engineering.
作者
王志龙
刘晓栋
赵桐
刘凯
武居昌宏
WANG Zhilong;LIU Xiaodong;ZHAO Tong;LIU Kai;MASAHIRO Takei(School of Mechanical and Precision Instrument Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China;Division of Artificial Systems Science,Graduate School of Engineering,Chiba University,Chiba 263-8522,Japan)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2021年第12期6505-6515,共11页
Chemical Industry and Engineering Progress
基金
国家自然科学基金(52006176,51876175)。
关键词
多相流
分布
浆料
粒子
可视化
multiphase flow
distributions
slurry
particle
visualization
