摘要
为深入理解锂离子电池(Lithium-Ion Battery,LIB)内部的多物理场耦合行为,更好地为锂离子电池的生产制造及优化等工作提供参考,文中通过数值模拟方式,在有限元仿真软件COMSOL Multiphysics中建立了更符合物理实际的锂离子电池电化学-热-力(Electrochemical-Thermal-Mechanical,ETM)耦合模型,并进行求解。该模型考虑了电池工作时电极与颗粒两个尺度中的应力生成,解决了以往模型中电极层面应力难以计算的问题。同时通过考虑应力对锂离子扩散及过电位的修正,更好地关联了应力与电化学间的关系。基于该模型,文中讨论了不同正极粒径对电池性能的影响。数值结果表明,当正极粒径小时,锂离子电池放电过程中各物理场的性能指标较好,电池能量密度增大,证明采用较小的正极粒径可提升锂离子电池性能。
In order to deeply understand the multi-physical field coupling behavior inside the LIB(Lithium-Ion Battery)and better provide reference for the manufacturing and optimization design of the LIB,a more physically realistic coupled ETM(Electrochemical-Thermal-Mechanical)model of the LIB is established and solved in the finite element simulation software COMSOL Multiphysics by means of numerical simulation in the present study.The model takes into account the stress generation in both electrode and particle scales during battery operation,which solves the problem of difficult calculation of stress at the electrode level in previous models,and better correlates the relationship between stress and electrochemistry by considering the correction of stress on lithium diffusion and overpotential.Based on this model,the effect of different positive electrode particle sizes on the battery performance is discussed in the study.The numerical results show that the performance index of each physical field during the discharge of LIB is better and the energy density of the battery is improved when the positive electrode particle size is small,which proves that the use of smaller positive electrode particle size can improve the performance of LIB.
作者
余润洲
李培超
YU Runzhou;LI Peichao(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)
出处
《电子科技》
2024年第9期1-7,共7页
Electronic Science and Technology
基金
国家自然科学基金(12272217)。
关键词
锂离子电池
多物理场耦合
电化学-热-力
能量密度
有限元仿真
应力
粒径
优化设计
lithium-ion battery
multi-physics field coupling
electrochemical-thermal-mechanical
energy density
finite element simulation
stress
particle size
optimal design