The size effect on degradation in lithium-ion battery cells is investigated by simulations of lithium iron phosphate/graphite LIB cells with different size. An electrical-electrochemical-thermal model considering degradation phenomena is modeled for a 1Ah pouch cell and a 55Ah pouch cell with an identical electrode design. Numerical results in the large cell shows the additional voltage drops of 27 mV and the mean temperature increase of 8 °C for 3C discharge due to overpotentials in metal current collectors and clear spatial imbalances of temperature, current density and electric potential. The capacity fade in the large cell is accelerated by about 33% for cycling operation due to the activated parasitic reactions at high temperature conditions. But even in an isothermal condition, the large cell still shows about 7% faster degradation than the small cell because it stays longer at high SOC in the charge process.

通过模拟不同尺寸的磷酸铁锂/石墨LIB电池，研究了尺寸对锂离子电池退化的影响。为具有相同电极设计的1Ah袋式电池和55Ah袋式电池建模了考虑降解现象的电化学热模型。在大电池中的数值结果显示，由于金属集电器中的过电势以及明显的温度，电流密度和电势空间不平衡，对于3C放电，额外的电压降为27 mV，平均温度升高了8°C。由于高温条件下激活的寄生反应，大容量电池的容量衰减可加快约33％的循环操作循环速度。但是即使在等温条件下