Stress Analysis of Graphite Anode under Various Binder Conditions in a Multiparticle Model through Multiscale Simulation and Experimental Verification

摘要

Quantifying and analyzing the stress of the battery system at different levels are important for ensuring battery stability and performance. Herein, a threedimensional multiparticle model to evaluate the stress generated within the active material particles of battery due to the particle–particle and particle–binder interactions is developed. Variations in binder conditions, such as binder distribution, thickness, and radius, as well as Young's modulus, are introduced to investigate their effects on the mechanical stress of graphite particles in the battery. Herein, it is demonstrated that larger binder distributions, lower thicknesses, and smaller Young's moduli and radii reduce the maximum particle stress of graphite. Moreover, smaller binder distributions and Young's moduli along with larger thicknesses and radii reduce the maximum and average binder stress values. The interfaces between the particle–particle and particle–current collector are the typical maximum stress locations. The average stress data obtained are applied at the electrode level for comparison with the experimental stress value. The experimental and the model average stresses are comparable, indicating the credibility of our model. These findings have considerable implications for minimizing the mechanical stress and probability of electrode fracture in the battery electrode operation and fabrication processes.