Electro-thermal Model using Advanced ECM Approach for Automotive Application

The burgeoning demand for electric vehicles (EVs) necessitates comprehensive electro-thermal modeling of Li-ion batteries. This study presents Advanced Equivalent Circuit Modeling (AECM) approach to create a precise electro-thermal model for Li-ion cells. The main goal is to provide reliable inputs for assessing vehicle performance and optimizing battery thermal management systems. Using a Design of Experiments approach, critical parameters like cell capacity, RC parameters, faradic efficiency, entropic coefficients, and specific heat capacity are derived. Tests like hybrid-pulse power characterization, capacity, and open circuit voltage are tailored to mimic real-world usage scenarios. The resulting models accurately predict voltage response, cell temperatures, and reversible/irreversible heat generation, validated against real-world data. Notably, these models predict heat and temperature across a wide range (-10°C to 60°C) and loading conditions, making them valuable for hardwarein-the-loop (HIL), software-in-the-loop (SIL), and model-in-theloop (MIL) simulations during EV development. Additionally, these models support test matrix design, failure mode analysis, and battery performance strategies. Limitations include challenges in predicting cell dynamics, particularly at lower state-of-charge (SOC) levels. Future work will integrate an aging model to enhance the models' utility. In conclusion, this research offers a robust electro-thermal model to improve Li-ion battery reliability and performance in electric vehicles, aligning with the growing demand for sustainable transportation solutions.