A multi-field model for charging and discharging of lithium-ion battery electrodes
A multi-field model for charging and discharging of lithium-ion battery electrodes
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DOI：
10.1007/s00161-020-00943-8
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发表时间：
2020-11
影响因子：
2.6
通讯作者：
Marek Werner;A. Pandolfi;K. Weinberg
中科院分区：
文献类型：
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作者：
Marek Werner;A. Pandolfi;K. Weinberg
提出了一个描述锂电极充放电过程的电化学-热力学模型。多物理场耦合是通过本构关系实现的，本构关系是在基于自由能密度定义的一致热力学框架内获得的，自由能密度是来自不同物理场的不同贡献的总和。该系统具有有限运动学特征，在变形局部性假设下，变形梯度被分解为弹性部分和非弹性部分的乘积。具体地，泰勒级数展开用于近似由于离子嵌入的非弹性变形。弹性部分可以交替地由两个有限的运动学模型的新胡克弹性，和麦克斯韦型粘弹性模型占时间依赖性的力学方面。该模型被实现到一个有限元代码，使用B样条基函数。通过实例说明了该模型的特点，表明化学-机械相互作用影响相的平衡浓度。该模型捕捉的阳极充电和放电过程的基本方面。
An electrochemical–thermomechanical model for the description of charging and discharging processes in lithium electrodes is presented. Multi-physics coupling is achieved through the constitutive relations, obtained within a consistent thermodynamic framework based on the definition of the free energy density, sum of distinct contributions from different physics. The system is characterized by finite kinematics, under the assumption of locality of deformation, and the deformation gradient is decomposed into the product of elastic and inelastic parts. Specifically, a Taylor series expansion is used to approximate the inelastic deformation due to ion intercalation. The elastic part can be described alternatively by two finite kinematics models of neo-Hookean elasticity, and a Maxwell-type viscoelastic model accounts for time-dependent mechanical aspects. The model is implemented into a finite element code that uses B-spline basis functions. We illustrate the features of the model by means of selects examples, showing that chemo-mechanical interaction affects the equilibrium concentrations of the phases. The model captures the fundamental aspects of the anode charging and discharging processes.