Search

Your search keyword '"Lim, Cheolwoong"' showing total 17 results
Start Over Author "Lim, Cheolwoong"
17 results on '"Lim, Cheolwoong"'

6. In situ and operando investigation of the dynamic morphological and phase changes of a selenium-doped germanium electrode during (de)lithiation processes

Author

Li, Tianyi, primary, Lim, Cheolwoong, additional, Cui, Yi, additional, Zhou, Xinwei, additional, Kang, Huixiao, additional, Yan, Bo, additional, Meyerson, Melissa L., additional, Weeks, Jason A., additional, Liu, Qi, additional, Guo, Fangmin, additional, Kou, Ronghui, additional, Liu, Yuzi, additional, De Andrade, Vincent, additional, De Carlo, Francesco, additional, Ren, Yang, additional, Sun, Cheng-Jun, additional, Mullins, C. Buddie, additional, Chen, Lei, additional, Fu, Yongzhu, additional, and Zhu, Likun, additional

Published
2020
Full Text
View/download PDF

9. 3D Simulation of diffusion induced stress in realistic LiCoO2 electrode particles of lithium ion battery generated by nano-CT

Author

Yan, Bo, Lim, Cheolwoong, Zhu, Likun, and Yin, Leilei

Abstract

Diffusion induces stresses in the electrode during charge and discharge processes of lithium ion batteries, which can cause deformation and even fracture, further result in the fade of capacity and duration. The 3D model coupling diffusion and induced stress is applied to the reconstructed LiCoO2 electrode particles determined by X-ray nanocomputed tomography technology, of which the nonuniform electrochemical intercalation reaction takes place on the surface. A code is developed to simulate the fully coupled diffusion and induced stress in the LiCoO2 electrode particles at different discharge rates. The simulations demonstrate the variable distribution such as concentration, reaction rate, hydrostatic stress, Von-Mises stress, and so on. The influence of the geometric characteristics of LiCoO2 electrode particle and material properties on the variables is revealed. The investigation can help to improve lithium ion battery design and manufacture through understanding the relationship between electrode morphology and mechanical endurance.

Published
2014

16. Simulation of heat generation in a reconstructed LiCoO2 cathode during galvanostatic discharge.

Author

Yan, Bo, Lim, Cheolwoong, Yin, Leilei, and Zhu, Likun

Subjects
*LITHIUM compounds, *COMPUTER simulation, *HEAT transfer, *LITHIUM-ion batteries, *CATHODES, *GALVANOSTAT, *ELECTRIC discharges, *COMPUTED tomography
Abstract

Abstract: A three dimensional numerical framework with finite volume method was employed to simulate heat generation of a semi lithium ion battery (LIB) cell during isothermal galvanostatic discharge processes. The microstructure of the LIB cathode electrode was experimentally determined using X-ray nano computed tomography technology. Heat generation in the semi LIB cell during galvanostatic discharge processes from different mechanisms, such as electronic resistive heat, ionic resistive heat, contact resistive heat, reaction heat, entropic heat and heat of mixing, was investigated. The spatial distribution of heat generation rates from different mechanisms was also studied. The simulation results demonstrate that the magnitude of heat generation rates spans a wide range in the electrode due to structural inhomogeneity. The simulation results of heat generation from the three dimensional model and the porous-electrode theory model were compared in this study. It is found that the typical Bruggeman coefficient, 1.5, underestimated ionic resistance in the electrolyte and overestimated electronic resistance in the cathode particles. In general, the three dimensional model predicted more heat generation than the porous-electrode theory model at large discharge rates due to the wider distribution of physical and electrochemical properties. [Copyright &y& Elsevier]

Published
2013
Full Text
View/download PDF

17. Three Dimensional Simulation of Galvanostatic Discharge of LiCoO2 Cathode Based on X-ray Nano-CT Images

Author

Yan, Bo, Lim, Cheolwoong, Yin, Leilei, and Zhu, Likun

Abstract

Based on the experimentally determined microstructure of a lithium ion battery (LIB) cathode electrode using X-ray nano-CT technology, a three dimensional simulation framework of galvanostatic discharge with finite volume method is presented. The tomography data were used to evaluate the homogeneity of porosity and tortuosity of the electrode. With this approach, galvanostatic discharge processes at different C rates were simulated and the local effects in the LIB cathode electrode during discharge processes were investigated. The spatial distribution of physical and electrochemical properties in the microsturcture of the cathode electrode, such as concentration, current density, open circuit potential (OCP), overpotential and intercalation reaction rate was revealed in this paper. The simulation results show that the distributions of those properties are very different from the results based on the pseudo two dimensional model. The physical and electrochemical properties distribute in a wider range due to the structure inhomogeneity, which may have a negative impact on LIB performance, especially at large discharge rates.

Published
2012

Catalog

Books, media, physical & digital resources
See catalog results