Degradation-Aware Optimization of Second-Life Battery Energy Storage System

Many Electrical Vehicle (EV) batteries are expected to be retired in the next 5-10 years. These batteries are retired when no longer suitable for energy-intensive EV operations despite having 70–80% capacity left. Second-life use of these battery packs has the potential to address the increasing demand for battery energy storage systems (BESS) in the grid and to create a robust circular economy for EV batteries. However, the degradation of second-life batteries (SLBs) significantly differs from that of their fresh counterparts. This paper presents a mixed-integer linear programming optimization algorithm that considers the degradation of SLBs. A Wöhler curve is derived for an SLB using real-world degradation data of SLBs. The algorithm is tested on a real-world extreme fast charging station (XFCS) load and real-time pricing (RTP) data from a utility. The results show that using that using this algorithm the SLBESS can provide 10 years of operation with minimum degradation cost.