Study on the effect of solar irradiance intermittency mitigation on electric vehicle battery lifetime

The rising penetration of intermittent power sources such as solar photovoltaic systems is a concern for electric utility operators, and techniques to mitigate the effect of power variability have been proposed. One method is to use electric vehicle (EV) batteries, connected through fast bidirectional chargers, as short time scale storage devices for intermittent power sources. This allows the high frequency components of intermittent power to be diverted to the EV battery, while the remaining, slowly changing power is fed to the AC distribution system. However, studies of lithium-ion (Li-ion) EV batteries have shown that frequent and rapid charging and discharging reduces battery lifetime. Using an empirically validated Li-ion battery degradation model, this paper demonstrates that the effect of intermittency mitigation (IM) on battery lifetime is small. This conclusion is validated with publicly available irradiance data and daily EV usage data from a large-scale study.