Review of Battery Management Systems

Abstract

In this work the authors investigate the different parts and functions offered by Battery Management Systems (BMS) specifically designed for secondary/rechargeable lithium batteries. Compared to other chemistries, lithium batteries offer high energy density and cell voltage, which makes them the most attractive choice for electronic devices including EV and RES. However, lithium technology is vulnerable and highly susceptible to catastrophic failures which result in fire. Hence, the use of electronic safety designs is a must. BMS are responsible for the monitoring of the battery state, ensuring operation within safe limits. BMS offer multiple functionalities with the state of charge (SoC) estimation being the most challenging hence the most studied by engineers. All estimation methodologies and algorithms have pros and cons, which best suits the application that is developed for. This research concludes that according to designers, the optimum BMS provides battery packs with the needed protection, good functioning conditions and accurate prediction for the battery’s state including charge and life. Finally, this research presents and validates an SoC algorithm based on the reformulated Peukert’s equation which is also valid for variable load and multi-pulsing scenarios with an accuracy exceeding 95%.