An efficient multi-state evaluation approach for lithium-ion pouch cells under dynamic conditions in pressure/current/temperature

• Published in: Applied energy 2023-06, Vol.340, p.121057, Article 121057
• Main Authors: Huang, Zhiliang, Wang, Huaixing, Yang, Tongguang, Chen, Zeye, Li, Hangyang, Chen, Jie, Wu, Shengben
• Format: Article
• Language: English
• Subjects: algorithms; Analytical approach; anisotropy; batteries; deformation; Dynamic conditions; energy; evolution; heat transfer; Lithium-ion pouch cell; Multi-state evaluation; Non-uniform characteristics; temperature
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2023.121057

Caption: An analytical model for lithium-ion pouch cells is proposed, including mechanical, thermal circuit and reaction sub-models. It can evaluate the multi-state distribution and evolution in gas/heat generation, temperature, pressure, and deformation. [Display omitted] •An analytical model and decoupling algorithm for lithium-ion pouch cells are developed.•Equations including mechanical, thermal circuit and reaction sub-models are formulated.•Uniform characteristics in local heating, heat conduction and shell deformation are included.•A sequential decoupling algorithm from the global to the local is proposed.•The approach evaluates the multi-state distribution and evolution under dynamic conditions. The current analytical and simulation models for lithium-ion pouch cells encounter challenges in accuracy and efficiency for battery management applications. This paper proposes an analytical model and decoupling algorithm for lithium-ion pouch cells. It can evaluate the multi-state distribution and evolution in gas/heat generation, temperature, pressure, and deformation. Analytic differential equations are formulated, including mechanical, thermal circuit and reaction sub-models. The analysis framework considers dynamic conditions (e.g., mechanical pressure, charging/discharging, heat dissipation) and uniform characteristics (e.g., local heating, anisotropic heat conduction, shell deformation). A sequential decoupling algorithm from the global to the local is proposed to address the convergence issue from the high-dimensional and strongly nonlinear equations. Iterative mechanisms are established to determine the solving parameters for eliminating confusion in engineering applications. The numerical and experimental results on three commercial pouch cells verified the approach performances, including stable convergence, millisecond efficiency, and 2% temperature error. The performances suggest its application prospects in energy storage and vehicle power systems.