锂电池介观尺度电化学-力学模型仿真分析  

Simulation analysis of mesoscale electrochemical mechanical model for lithium-ion batteries

作　　者：王宁 昝文达 张睿 丁飞 WANG Ning;ZAN Wenda;ZHANG Rui;DING Fei(State Key laboratory of Reliability and Intelligence of Electrical Equipment,School of Electrical Engineering,Hebei University of Technology,Tianjin 300130,China)

机构地区：[1]河北工业大学电气工程学院省部共建电工装备可靠性与智能化国家重点实验室,天津300130

出　　处：《电源技术》2024年第11期2209-2218,共10页Chinese Journal of Power Sources

基　　金：河北省自然基金青年项目(E2022202181);河北省高等学校科学技术研究项目“青年拔尖人才项目”(BJK2024123);河北省全职引进高端人才科研项目(2020HBQZYC017);河北工业大学“科技新星”项目。

摘　　要：基于电子计算机断层扫描数据搭建了锂离子电池介观尺度电化学-力耦合模型,模型还原了电极内部真实的结构并揭示了微观结构、参数对电极性能的影响。提高颗粒的固相扩散系数或降低粒径可以提高颗粒的锂化程度,从而提升电池的倍率性能;正极电解质膜阻的增加会加剧电极的极化。此外,放电倍率增加会导致电极颗粒锂化程度不均匀分布,造成更大的应力。介观尺度模型仿真结果对电极微观结构设计和材料选取有着重要的参考价值。This article presents a microstructure-resolved electrochemical-mechanical coupling model for lithium-ion batteries constructed based on X-ray nano computed tomography date.The model reconstructs the true internal structure of the electrode and reveals the influence of microstructure and parameters on electrode performance.Research has found that increasing the diffusion coefficient or reducing the particle size can effectively improve the lithiation degree of active material particles and enhance performance at high-rate discharge.Moreover,the increase in resistance of CEI membrane exacerbates electrode polarization.In addition,an increase in discharge rate can lead to uneven distribution of lithiation degree of active material particles,resulting in high internal stress.The simulation results of microstructure-resolved models can provide a basis for electrode microstructure design and material selection.

关 键 词：锂离子电池 介观尺度模型 电化学特性 力学特性 微观结构 

分 类 号：TM912[电气工程—电力电子与电力传动]