Aging and Characterization of Li-Ion Batteries in a HEV Application for Lifetime Estimation

This paper deals with the aging and characterization of lithium-ion (Li-ion) batteries for life estimation evaluation. The most important aging characteristics of a real driving cycle for hybrid electric vehicle application, such as initial State of Charge (SoC) and Depth of Discharge (DoD), are used to synthesize an aging profile to be reproduced in laboratory based on statistical analysis. Implementing the synthesized driving cycle at higher temperature results in an accelerated aging. Periodic assessment tests are also performed within the aging activity in order to monitor the behavior of two battery aging parameters, namely, resistance and capacity. The evolution of these two parameters is monitored and a general framework for battery parameter estimation based on a predictor/corrector scheme is presented.