Numerical Prediction of Multiscale Electronic Conductivity of Lithium-Ion Battery Positive Electrodes
Numerical Prediction of Multiscale Electronic Conductivity of Lithium-Ion Battery Positive Electrodes
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DOI：
10.1149/2.1221908jes
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发表时间：
2019-05-22
影响因子：
3.9
通讯作者：
Maire, E.
中科院分区：
文献类型：
--
作者：
Cadiou, F.;Etiemble, A.;Maire, E.
在多尺度下，基于LiNi 1/3 Mn 1/3Co 1/3 O 2和/或碳包覆的LiFePO 4、炭黑和聚偏氟乙烯混合物的锂离子正极复合电极的电子电导率被建模。通过X射线层析成像和FIB/SEM纳米层析成像在3D中数值地获得电极微结构，并使用快速傅里叶变换（FFT）方法进行数值分割以进行静电模拟。这样的模拟容易且快速地执行，因为它们直接在由3D体积中的体素表示的网格上计算。数值计算结果与实验测量的多尺度电子电导率的宽带介电谱（BDS）进行了比较。一个很好的预测实现了体电导率的C/LiFePO 4相和CB/PVdF混合物。因此，X射线和FIB/SEM层析成像，FFT模拟方法和BDS的组合非常适合于了解电极组成和微观结构对其电子电导率的影响。(C)2019电化学学会。
The electronic conductivity, at the multiscale, of lithium-ion positive composite electrodes based on LiNi1/3Mn1/3Co1/3O2 and/or carbon-coated LiFePO4, carbon black and poly(vinylidene fluoride) mixture is modeled. The electrode microstructures are acquired numerically in 3D by X-ray tomography and FIB/SEM nanotomography and numerically segmented to perform electrostatic simulations using Fast Fourier Transform (FFT) method. Such simulations are easy and quick to perform because they are directly computed on the grid represented by the voxels in the 3D volumes. Numerical results are compared with experimental measurements of the multiscale electronic conductivity by broadband dielectric spectroscopy (BDS). A good prediction is realized for the bulk conductivities of the C/LiFePO4 phase and the CB/PVdF mixture. The combination of X-ray and FIB/SEM tomography, FFT simulation method, and BDS is thus well adapted to understand the influence of the electrode composition and microstructure on its electronic conductivity. (C) 2019 The Electrochemical Society.