BATTERY MANAGEMENT SYSTEM FOR ELECTRIC VEHICLE PASSIVE CELL BALANCING ON LITHIUM ION POLYMER BATTERY

Automotive industry is moving forward for green technology which is Electric Vehicles. Battery is one of the critical components in an Electric Vehicle. Lithium Ion Polymer battery offers better performance compare to other types of the battery in the market. However, Lithium Ion Polymer battery is very sensitive to over voltage and under voltage which can be hazardous to the user. Moreover, the imbalanced cell in a battery affects the performance and life usage of the battery. By having a proper monitoring and balanced cell, it can prolong and maintain the performance of the battery. The purpose of this work is to adopt a passive cell balancing during the charging of Lithium Ion Polymer battery. This work produces State of Charge profile of Lithium Ion Polymer battery using measured parameters such as voltage, charging current and temperature. The work on battery testing was done to calculate the State of Charge and verified using Orion Battery Management System data. In this report, findings on both methods are discussed. A prototype of passive cell balancing was designed using a PIC16F877A microcontroller. However, the prototype is still under way. Therefore, the effectiveness cannot be determined at the moment.