Lithium-ion battery modeling
Lithium-ion batteries comprise a very promising energy storage medium for electric and hybrid electric vehicles compared to other energy storage approaches. However, their performance is impeded by certain issues such as capacity fade, cyclic life limitation, and limited abuse tolerance. It is desirable to uncover the underlying physical and electrochemical mechanisms responsible for these performance degradations. Our research focuses on using modeling and numerical simulations to better understand these mechanisms, especially in terms of intercalation-induced stress and heat generation, in order to optimize battery design to improve battery performance.
We started the modeling from electrode particle scale simulations. Two phenomena were considered within single ellipsoidal particles: intercalation-induced stress and heat generation because (1) cyclic loading of intercalation-induced stress results in particle fracture, which is one putative capacity fade mechanism of Li-ion cells; and (2) excessive heat generation in Li-ion batteries, resulting in thermal runaway, could lead to complete cell failure. A thermal stress analogy was proposed to model intercalation-induced stress. With a surrogate-based approach, numerical simulations were systematically conducted to understand the underlying physical mechanisms and optimize the particle configuration design.
Optimizing a battery’s design requires a battery scale model. However, due to the geometric complexities of battery materials and the multiple physical processes, it is extremely expensive to implement a full-scale battery model with all the microscopic structure details resolved. Currently, we are exploiting the possibility of utilizing multiscale modeling approach to extend our particle scale model to the battery scale.
<Multiscale modeling framework>
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<Von Mises stress inside a single particle> |
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Representative publications:
1. Zhang, X., Shyy, W., Sastry, A.M., “Numerical Simulation of Intercalation-Induced Stress in Li-Ion Battery Electrode Particles”, Journal of the Electrochemical Society, 154, (2007), pp. A910-A916.
2. Zhang, X., Sastry, A.M., and Shyy, W., “Intercalation-induced Stress and Heat Generation within Single Lithium-ion Battery Cathode Particles”, Journal of the Electrochemical Society, Vol. 155, (2008), pp. A542-A552.
Faculty Advisor: Professor Wei Shyy
Graduate Students: Xiangchun Zhang and Wenbo Du
Post-Doctoral Researcher: Dr. Amit Gupta
In collaboration with: Professor Ann Marie Sastry
