Thermal behavior analysis of Pouch Lithium ion Battery using distributed electro-thermal model

Abstract

Pouch lithium ion batteries are applied in electronic vehicles far and wide, due to their high energy density, smaller internal resistance and convenient transportation. However, pouch-type batteries are easier inducing thermal inhomogeneities and cause safety problems, especially for large-sized batteries. Therefore, in order to study the thermal behaviors of Pouch Lithium Ion Battery, a distributed electro-thermal model is established in this paper, which is developed by coupling the network equivalent circuit model and the 2D thermal model. Using this model, we can obtain the distributions of temperature, local SOC and current density on the cell plates. Then, a simulation analysis based on this model has been given for the thermal behavior of a pouch cell under different discharge rates (1C, 2C, 3C, 4C). Results verify that the larger discharge rate always causes a higher temperature rise, what's more, the highest temperature area is not invariable in the process of discharge.