Tensile/Electrical Performance Simulation And Microstructure Modeling Of Carbon Fiber Composite Electrode

The microstructure of the composite electrode is different from the traditional fiber-reinforced composite.The matrix has complicated three-dimensional pore cross-linked structure and is filled by the conductive phase which is not carried.The traditional macro-mechanics or meso-mechanics analysis method has the problems of mesoscopic modeling difficulty and low accuracy.In this paper,a three-dimensional stochastic modeling method for complex structures is proposed.A mesomechanical cell model that reflects the real microscopic complex structure is established to predict the macroscopic elastic properties of the composite electrode materials.At the same time,an electrochemical model of lithium battery was set up to analyze the discharge characteristics of the model,which would be the foundation for the future study of force-electricity coupling of multi-functional structure batteries.Research results mainly from several aspects:Use MATLAB programming language and reverse-engineering software to establish a parametric complex microstructure cell model generation method.Based on the Monte-Carlo principle,this algorithm simulates the random formation of matrix material in three-dimensional space through the random selection growth of point nuclei in three-dimensional space grid in 26 directions,and realizes the complex pore microstructure of the composite material Finally,the point cloud data is transformed into a three-dimensional solid model reflecting the complex pore structure of the material through the parametric method.The method can meet the need of mesoscopic modeling of different complex three-dimensional microstructures and lay a foundation for the finite element analysis of mesomechanics.The macroscopic mechanical properties of composite materials based on the three-dimensional random growth algorithm with complex microstructure were calculated by Abaqus platform and compared with the experimental data of the literature materials.It is proved that the modeling method and the model Accuracy and effectiveness.The macroscopic mechanical properties of the composites were studied.It is shown that the modulus matching between the components of the composites is the key factor that affects the macroscopic mechanical properties and provides the basis for the mechanical optimization design of the composite electrode.Based on the electrochemical model of Li-ion battery,the discharge performance of the composite structure battery was simulated.Based on the electrochemical parameters of the lithium iron phosphate battery material in the related literatures,the electrochemical model was used to simulate the discharge performance.The simulation results show that the electrochemical model of the single particle can simulate the discharge characteristics of the battery,but due to the measurement method and the uncertainty of some electrochemical reaction parameters,the discharge curve of the battery with the real structure is poor.The innovation of this paper lies in the cross-integration of a variety of traditional analytical simulation methods for a new multi-functional material,laying a foundation for the future electro-mechanical coupling analysis of multi-functional structures.