Study on the Aging Characteristics of Li-ion Battery Based on the Electro-Thermal and Aging Joint Simulation platform

With the wide application of the power battery system for EVs and energy storage battery system for the power grid, the analysis of batteries aging characteristics has become a hot spot. However, the aging of battery is a complex process, which needs to consider the combined effect of electrical and thermal processes. Therefore, this paper establishes an electrothermal and aging joint simulation platform considering the interaction of internal parameters of battery, heat transfer characteristics, and current feedback. The platform can simulate the closed-loop process of the internal thermal aging of the battery of the real working condition. Firstly, this paper introduces how to combine the electrical model, thermal model, and aging model of the battery to form the electro-thermal and aging joint simulation platform, and gives the process of battery parameters transfer and feedback. Then, through the simulation analysis, the curves and differences of battery capacity degradation under the single aging process and electro-thermal and aging process are compared. The results show that the joint simulation platform can get the process of cell temperature change and SOC change under the actual operating conditions, and the battery capacity declines faster under the electro-thermal and aging process, which verifies the effectiveness and accuracy of the joint simulation platform.