During charging and discharging, the insertion and extraction of lithium ions into and from the active materials can cause stress in a lithium ion battery (LIB). Excessive stress will lead to cracking, breaking and pulverization of active particles, which can result in multiple failure modes such as capacity decay and life reduction of the battery. In this research, an electrochemical and mechanical coupling model of a LIB with the NCM cathode and graphite anode is built at mesoscopic scale. The electrochemical and mechanical characteristics of the model during the charging process are analyzed. By changing the charging rates and design parameters of the anode electrode such as the particle radius, spacing coefficient, electrode thickness and diffusion coefficient, the effects of them on the lithium concentration, strain and stress in the anode particles during the charging process are investigated. The results show that lower charging rate, greater spacing coefficient, smaller electrode thickness and greater diffusion coefficient could help to decrease the stress in anode particles during charging.

在充电和放电过程中，锂离子在活性材料中的嵌入和脱出会导致锂离子电池 (LIB) 产生应力。过大的应力会导致活性粒子开裂、破碎和粉化，从而导致电池容量衰减、寿命缩短等多种失效模式。在这项研究中，LIB 与 NCM 阴极和石墨阳极的电化学和机械耦合模型在细观尺度上建立。分析了模型在充电过程中的电化学和机械特性。通过改变负极的充电速率和设计参数，如颗粒半径、间距系数、电极厚度和扩散系数，它们对锂浓度的影响，研究了充电过程中阳极颗粒中的应变和应力。结果表明，较低的充电速率、较大的间距系数、较小的电极厚度和较大的扩散系数有助于降低充电过程中阳极颗粒的应力。