Study on aging characteristics of lithium-ion batteries for thermodynamic phases

Abstract

In order to derive the new charging algorithm which prolongs the lifetime of lithium ion batteries (LiBs), aging rates of LiBs for different phases and currents were analyzed. It was confirmed by ETM (Electro thermodynamic measurement) that ICR17335 of LiBs have 9 different phases over state of charge (SoC). Studies have shown that the phase is closely related to the aging rate enough to have a maximum difference of 2.5 times among phases. However, it was confirmed that the differences of the aging rates for different currents under 1C were insignificant. Therefore, it is difficult to derive a new charging algorithm that extends the lifetime by controling the current value according to the phase at the current condition under 1C. Further studies are required at currents above 1C to derive meaningful charging algorithms.