State-of-charge estimation for balancing control in a battery energy storage system
Loading...
Date
2017-06
Authors
Nur Hidayah Hashim
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Lithium ion (Li-ion) cells have been used in almost everything around us such as cell phones, digital cameras, laptop computers, and in many other electronic devices and nowadays there are more demanding applications with higher usage battery like Hybrid and Electric Vehicles (HEV). With bigger applications, we need bigger size of batteries as well as higher quality in their performance. Battery management system needs to improve the performance of the battery with such high demands to be able to deliver the full use of the battery. Battery management systems are affected by three types of battery cell imbalance which are state of charge (SoC) imbalance, total capacity differences and impedance differences which later results in premature cell degradation, safety hazards, early charge termination due to overcharged and also early discharge termination. To avoid on incomplete use of energy, safety hazards, and reduced longevity of battery life, an approach on cell balancing based on state of charge estimation is proposed. The parameters that affected the state of charge (SoC) are investigated and the study is carried out to prove and compare the accuracy of the state of charge (SoC) estimation. In this project, Li-ion Rechargeable Battery is used and the battery’s manufacturer data is used as reference to obtain the percentage on accuracy of the results from the experiment. The study of state of charge (SoC) estimation is focusing on the most obvious parameters which are temperature, ampere-hour, voltage and capacity. These parameters involved in the study of balancing system of battery energy storage system along with proper guidelines and suggestions by the manufacturer of the battery used.