摘要
相场断裂方法通过定义序参量来表示裂纹,利用系统最小能量变分原理得到描述裂纹发展的控制方程。通过对控制方程的推导,建立了相场理论的框架,包括基于能量原理建立相场断裂损伤演化方程和边界条件。对含缺口平板进行了拉伸和剪切模拟,断裂路径和支反力均与文献结果吻合。利用相场方法模拟了锂离子电池不同直径硅负极充电时的裂纹扩展问题,结果表明:较大直径(400nm)硅颗粒在充电时由于表面受到较大拉应力,很快发生开裂并向内部扩展,且断裂能量释放率对裂纹扩展影响较大,能量释放率较小时,起裂点较多,裂纹密度较大;小直径(100nm)硅颗粒在充电时内部发生断裂,且其断裂时间要早于大尺寸硅颗粒。
In the phase field fracture method,the crack is represented by defining an order parameter,and the governing equation describing the crack development is obtained by using the minimum energy variational principle for the system.In this paper,the framework of phase field theory was established through the derivation of governing equations,including the establishment of phase field fracture damage evolution equation and boundary conditions based on the energy principle.Tensile and shear simulations were carried out on a plate with a notch,and the fracture path and support reaction were in good agreement with the results reported in the literature.The crack propagation of lithium-ion batteries with different diameters of silicon anode during charging was simulated using the phase field method.Results show that the large-diameter(400 nm)silicon particles quickly exhibit crack during charging due to the large tensile stress on their surfaces,and the crack propagates inwards.The fracture energy release rate has a great influence on the crack propagation,and a small energy release rate results in more crack initiation points and a high crack density.In comparison,internal fracture appears in small-diameter(100 nm)silicon particles during charging,and the fracture time is earlier than that of large-sized silicon particles.
作者
张可
刘靖
房冉冉
王维
ZHANG Ke;LIU Jing;FANG Ranran;WANG Wei(School of Intelligent Manufacturing and Control Engineering,Shandong Institute of Petroleum and Chemical Technology,Dongying 257061,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《电源学报》
2025年第7期266-273,共8页
Journal of Power Supply
基金
东营市科学发展基金资助项目(DJ20211014)。
关键词
相场法
锂离子电池
硅纳米颗粒
断裂
Phase field method
lithium-ion battery
silicon nanoparticle
fracture
