State of Health Characterization and State of Charge Estimation Inaccuracies of Aged Batteries in Smartphones
5.5.2017, 14:00 , 3945
This work studies the charging and discharging curves of smartphone batteries with the goal of finding parameters serving as indicators for capacity fading. Six differently aged batteries are charged and discharged using three different devices in order to classify them into two groups according to their capacity based on the parameters: time to reach end voltage, charging rate (C-rate), capacity and energy. From the classification results, the parameter that most reliably classifies the batteries is the time to reach end voltage. The discharging experiments also show that aged batteries discharge faster at a lower SOC than newer batteries because the capacity of the battery is not accurately estimated. The presented results demonstrate the shortcomings in SOC estimation and further the study of the effects of capacity fading on SOC estimation.