An enhanced circuit-based battery model with considerations of temperature effect

Accurate battery performance prediction is important for battery management system, battery maintenance, and multi-cell battery pack design. A variety of battery models have been proposed and validated to capture battery behaviors, such as circuit features and nonlinear capacity features. However, temperature effect is still poorly considered in most existing models. In this paper, we aim at filling this gap by developing an enhanced battery model by introducing an analytical model into the existing circuit-based model to evaluate battery dynamic behaviors and nonlinear capacity effects for accurate state of charge (SOC) estimation and runtime prediction, which not only takes advantages of circuit-based models but also takes considerations of temperature effect. Extensive simulations and tests are carried out on Arbin battery testing equipment using Heter 26650(LiFePO4) lithium-ion battery, and the comparison between experimental results and simulation results show that the proposed enhanced battery model can accurately predict battery performance under various thermal conditions. The model can also be extended to variety kinds of batteries and applications easily.