Smart Battery Management System with Active Cell Balancing

Abstract

Background/Objectives: Batteries are extensively being used in transportation, military, aerospace and portable applications like mobile phones and laptops. Also, battery driven Electric Vehicles (EVs) are replacing conventional vehicles to reduce pollution and dependence on conventional energy resources like petroleum and diesel etc. Methods/Statistical analysis: Generally batteries operate in the form of battery packs consisting of string of cells in series and parallel manner providing high voltage, current and power as required for different applications. Findings: Batteries faces many problems like charge imbalance, thermal runaway, over voltage and under voltage due to high charge/discharge profile. Charge imbalance affects overall pack performance as well. An efficient and sophisticated Battery Management System (BMS) that monitors and controls the critical parameters of the battery for smooth running and better performance of a battery. An embedded system was designed using a battery monitoring fuel gauge IC (BQ76PL536) and a buck-boost converter for cell balancing. Conclusion: This paper demonstrates a novel battery management system which actively monitors the critical parameters like voltage, capacity and performs as an active balancing of cells in a battery pack whenever required. The system is integrated with MSP430 microcontroller for monitoring and controlling purpose. Proposed battery management system continuously monitors each cell voltage in a battery pack and performs cell balancing if voltage difference between cells exceeds the threshold value.