Crucial Examination of Thermal Behavior of Solid-State Battery for Intelligent Gray Box Model-based Automotive Battery Management Systems

Solid-state batteries (SSBs) represent one of the most promising technologies for next-generation energy storage systems, offering potential advantages in safety, energy density, and longevity compared to traditional lithium-ion batteries. However, comprehending and managing the thermal behavior of these batteries across a wide range of operating conditions is essential for ensuring their safe and reliable operation. Furthermore, gray box modeling-based state estimation and control are extremely crucial due to the higher degree of nonlinearity exhibited under dynamic operating conditions of SSBs. Gray box modeling is a fusion of equivalent circuit models and data-driven techniques, requiring battery test data and information on charging/discharging and thermal characteristics of SSBs. Therefore, this paper presents a comprehensive analysis of the thermal behavior of SSBs through laboratory experiments conducted in a controlled environment. Additionally, it investigates the thermal characteristics of SSBs under various charging and discharging conditions to assess their suitability for e-mobility applications. Moreover, it examines the thermal behavior and stability of SSBs and introduces a concept of a gray box modeling-based temperature detection scheme for an effective thermal management system. The insights gained from this study can inform the development of advanced thermal management strategies and contribute to the design of safer and more efficient solid-state battery technologies for e-mobility applications.