A Comprehensive Study on Battery Management System and Dynamic Analysis of Lithium Polymer Battery

Abstract

The battery management system (BMS) is the most vital components of an electric vehicle. The main objective of the BMS is to ensure safe and consistent battery operation. To ensure proper functioning of the battery, state measuring and conditioning, cell balancing and control of charge are features that have been realized in BMS. The performance of different types of batteries is different under different environmental and working conditions. These irregularities in the performance of a battery are the primary challenge to the implementing of these functions in the BMS. State estimation of a battery, i.e. state of charge (SOC) and state of health (SOH), is a crucial function for a BMS. Li-Polymer battery has high discharge rate per unit mass and hence are very suitable for applications in electric automotive industry. This project addresses the modelling of a typical Li-Polymer battery and its dynamic characteristics. These battery models emulate the characteristics of real life Li-Po batteries, and help predict their behavior under different external as well as internal conditions. A dynamic model of lithium-polymer battery is designed using MATLAB/Simulink® in order to study the output characteristics of a lithium polymer battery unit. Dynamic simulations are done, which includes the effects of charging/discharging and operating temperature on battery terminal voltage output. The simulation results when compared to relevant studies, validated the model developed in the project.