Loss-of-life investigation of EV batteries used as smart energy storage for commercial building-based solar photovoltaic systems

Abstract: This study presents a loss-of-life (LoL) analysis for electric vehicle (EV) batteries, when they are being used as smart energy storage (SES) systems in a typical solar photovoltaic (PV) system installed in building environment. EVs can be considered as ideal energy storage for solar PV system installed in commercial/office buildings. This is attributable to the fact that the idle time-period of the EVs during the daytime, and the time-period during which the solar PV requires the energy storage intersect perfectly. However, it is to be demonstrated that using EVs as SES for solar PV system in commercial/office buildings would not have a significant impact on the battery lifetime and driving range of EVs. Hence, LoL analysis is essential to get a clear picture on the expected LoL for the EV batteries when EVs are used as SES for solar PV. Furthermore, the LoL of the individual EV batteries depends on the priority criteria used for charging/discharging the EVs, namely time coordinated and power coordinated vehicle-to-grid (V2G) algorithms. Hence, a comparison of LoL for different types of EVs while using different priority criteria in both the types of V2G is presented. © The Institution of Engineering and Technology 2017