Power conversion is a significant cost in second-use battery energy storage systems (2-BESS). 2-BESS is a sustainable pathway for retired batteries of electrical vehicles (EV) to provide energy storage for the grid and EV fast charging. We present and demonstrate the optimization of Lite-Sparse Hierarchical Partial Power Processing (LS-HiPPP) for battery degradation over the potential lifetime of the 2-BESS. LS-HiPPP has a significantly better performance tradeoff with lower power processing than other partial and full power processing architectures. 
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                            Economic Viability Assessment of Repurposed EV Batteries Participating in Frequency Regulation and Energy Markets
                        
                    
    
            The high cost and growing environmental concerns surrounding lithium-ion batteries have motivated research into extending the life of electric vehicle(EV) batteries by repurposing them for second life grid applications. The incorporation of repurposed electric vehicle batteries (REVBs) has the potential to decrease the overall cost of new battery energy storage systems (BESS) and extend the useful life of the materials. This paper focuses on maximizing daily profit that can be made from REVBs by stacking two grid services such as frequency regulation and energy arbitrage while minimizing battery capital cost by using second life EV batteries. A model for battery management with stacked frequency regulation and energy arbitrage is developed and tested using PJM market data. A mixed integer linear programming (MILP) is used to solve the optimization problem. It is found that REVBs can generate higher net profits than a new BESS. 
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                            - Award ID(s):
- 1659882
- PAR ID:
- 10229913
- Date Published:
- Journal Name:
- 2021 IEEE Green Technologies Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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