Polycrystalline LiNixCoyMn1−x−yO2 (PC-NCM) cathodes are widely used in Li-ion batteries due to their high operating voltage and gravimetric capacity. However, their performance declines due to intergranular fracture induced by chemo-mechanical interactions. This study develops a chemo-mechanical-damage fully coupled model to simulate and analyze the electrochemical performance, crack initiation, and propagation of nickel-rich PC-NCM particles during charging. Based on the anisotropic volume changes and diffusion of the primary particles, this work specifically examines the effect of stress on Li diffusion. Additionally, the effect of concentration-dependent material properties on the electrochemical behavior and crack development in PC-NCM particles is also analyzed. The mechanical degradation of PC-NCM particles during cycling is modeled by simulating the decrease in fracture energy. In addition, the study explores the effect of radial rod-like structural design on the electrochemical and mechanical properties of PC-NCM particles. The results show that coupled stress helps promote Li diffusion. The degradation of fracture energy, accelerating crack propagation in PC-NCM particles and leading to a decline in SOC. Concentration-dependent material properties significantly affect SOC estimation. The radial rod-like structure enhances the SOC and rate performance of PC-NCM particles but exacerbates radial cracking in the central region. This model provides new insights into the chemo-mechanical behavior of PC-NCM particles and offers guidance for their structural design and performance optimization.
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