预紧力对锂离子电池充电性能的影响OA

To clarify the effect of preload pressure on the charging performance of lithium-ion batter-ies and determine the optimal preload pressure value,a multi-physical field coupling model was es-tablished for a ternary-graphite pouch cell.The model accuracy was verified using test data under different C-rates and preload pressures.The influences of porosity and active specific surface area on the charging performance were analyzed,and the optimal preload pressure for the best charging per-formance was predicted.On one hand,preload pressure compresses the electrodes,which hinders the lithium-ion transfer in the electrolyte.On the other hand,it changes the contact state among elec-trode materials,thereby affecting the charge transfer resistance.The combined effects of the afore-mentioned mechanisms result in 175 kPa being the optimal preload pressure for 2.5 C-rate charging,at which the battery exhibits the minimal internal resistance and the best charging performance.This study elaborates on the impact of preload pressure on the charging performance of lithium-ion bat-teries and provides theoretical guidance for the design of preload pressure.