An electro-thermal model and its electrical parameters estimation procedure in a lithium-ion battery cell

Abstract

Abstract In this work, an electro-thermal model of a single lithium-ion battery cell has been developed in Simulink-Simscape environment. The model is divided in two interacting parts: the electrical and the thermal one. The electrical model consists of one Resistor-Capacitor branch circuit that is coupled to a thermal model consisting of a discretized volume, representing the battery cell, built on the basis of the thermal-electrical analogy. The heat generated by the cell is estimated using a lumped heat source approach. One of the novel aspects of the work is the definition and detailed description of an automatic procedure to extract the parameters of the RC circuit from pulse discharge tests, based on a Multi-Linear Regression Model approach. The electrical and thermal performance of the model was validated with dynamic and static measured data: the mean square error of the voltage prediction in dynamic conditions is 0.00027 V2. In static conditions, the mean square error of the voltage and temperature predictions are 0.014 V2 and 2.28 °C2, respectively. This model, due to its ease of application, can be used as a tool to define new modules architecture, as well as to support the design of the battery cooling system.