Investigating the Sources of Uncertainty in Capacity Estimation of Li-Ion Batteries

Li-ion batteries have shown great potential due to their numerous advantages and therefore, have been established as the main power source in various mobile applications such as consumer electronics and electrified transportation. In stationary energy storage applications, Li-ion batteries have emerged as a reliable solution; furthermore, they can facilitate the integration of renewable energy sources into the power grid. To achieve an efficient and reliable performance, Li-ion batteries need to be managed carefully, especially, battery aging effects should be accurately monitored over the battery lifetime. Capacity is one of the most important indicators of battery aging which can also be used to predict the run-time of the battery-powered application. Therefore, in this paper, some of the less-frequently explored sources of uncertainty, such as hysteresis, temperature, and polarization, which can significantly impact Li-ion battery capacity estimation are investigated. The investigations are based on experimental laboratory tests conducted on a Li-ion battery cell. The insights provided by this work can be used towards establishing confidence bounds on battery capacity estimates.