The Effects of Pulsed Charging Current on the Performance and Lifetime of Lithium-Ion Batteries

The pulsed current charging has been proposed in the literature to improve the performance and maximize the lifetime of lithium-ion batteries by eliminating concentration polarization and improving the active material utilization.However, there are few studies on this charging technique, and some of them hold opposite opinions.Moreover, the effect of the pulsed current is inconclusive due to the changeable current profile and conditions.Therefore, the main objective of this work is to prove that the pulsed charging current under suitable conditions can improve the performance and extend the lifetime of lithium-ion batteries.Various pulsed current charging modes and their effects on battery performance and lifetime are reviewed.Moreover, the main factor that impacts the battery performance and lifetime are analysis and discussed according to the previous studies.The effects of pulsed current on the charging performance of batteries are experimentally investigated.The considered conditions include current modes, frequency, duty cycle, amplitude, and temperature.The main factors that impact the performance of batteries (i.e., obtained capacity, maximum rising temperature, and charging time) are analyzed and discussed.The results illustrate that the pulsed current has no significant effect on the improvement of the performance of batteries.The effects of the pulsed current charging at a frequency range between 0.05 Hz and 2 kHz on battery lifetime are studied through aging tests.Compared to the traditional Constant Current (CC) charging, the pulsed current can extend the lifetime, where the PPC charging at 2 kHz can improve the lifetime up to 105.5%.Moreover, the impacts of pulsed current charging on the degradation mode of batteries are determined by a two-stage degradation model.The results of the Internal Resistance (IR) evolution and the changes in Incremental Capacity Analysis (ICA) curves are presented to comprehensively analyze the effect of the pulsed current on battery lifetime.The scientific contribution of this work is summarized as follows: the pulsed current charging has no significant improvement in performance but can significantly extend the lifetime of lithium-ion batteries, by more than 100%.iii ResuméDen pulserende strømopladning er blevet foreslået i litteraturen for at forbedre ydeevnen og maksimere levetiden for lithium-ion-batterier ved at eliminere koncentrationspolarisering og forbedre udnyttelsen af aktivt materiale.Der er imidlertid få undersøgelser om denne opladningsteknik,