THE EFFECTS OF MODIFIED CHARGE ON LITHIUM – ION BATTERY FOR HEALTH AND LIFE PREDICTION PURPOSES OF BATTERY USING MACHINE LEARNING

• Main Author: Ihsan, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/36591
• Institution: Institut Teknologi Bandung

Lithium batteries are well known that have been used in recent years and today there is a transition period where fossil energy has been taken over gradually by renewable energy. In this condition, batteries play an important role in energy storage. Lithium-Ion is one of the batteries that is very suitable for storing electrical energy. But lithium batteries are quite expensive so a lot of research aims to examine the performance degradation of the lithium-ion battery. Capacity degradation as a result of the modified charging and its influence on internal resistance was the object of this research. The research used commercial batteries. The obtained result showed that the modified charging method was proven to be faster in increasing battery resistance than the prior CC-CV charging method. In this research machine learning such as Support Vector Machine (SVM), linear regression, and Seasonal ARIMA (SARIMA) had been used to predict battery's life. Linear regression in predicting for 20 cycles ahead, gave MSE 624.01, RMSE 24.98, MAPE 0.77%, and coefficient of determination (R2)of the predictive model was 34%. Meanwhile, Support Vector Machine for 20 cycles gave MSE 612.37, RMSE 24.75, MAPE 0.74% and coefficient of determination (R2) of the predictive model was 35%. By applying the SARIMA prediction method for 20 cycles gave MSE 202.37, RMSE 14.23, MAPE 0.43%, and the coefficient of determination (R2) of the predictive model was 76%. Modified charge method could increase battery life when observed from its capacity. The method named as multi-current step III could make the lithium-ion battery has a trend of capacity degradation slower than CC-CV charge and multicurrent step II. The battery life could be extended when used modified charge method such as multi-current step III. In this research multi-current step III could prolong battery life up to 29 cycles with total cycles were 435 cycles. It was higher than the battery that uses the CC-CV charging method which had total cycles of 406 cycles and battery with multi-current step II charging method which had total cycles of 325 cycles. The longest life was 435 cycles because this research applied a fast charging method with 100% deep of discharge.