Modeling and simulation framework for hybrid energy storage systems including degradation mitigation analysis under varying control schemes

Battery Energy Storage Systems (BESSs) are an increasingly prevalent part of the Great Britain Grid as the energy mix shifts to a higher proportion of intermittent generation such as solar and wind. National Grid ESO (Electricity System Operator) offers a number of frequency response services that can be provided by Energy Storage Systems (ESSs). A significant drawback of BESSs is the degradation experienced when subjected to frequent cycling compared to other energy storage mediums. Modeling and simulation of these systems is key to understanding the impact that hybridization can have on the lifetime and economic viability of such systems. In this paper, a framework for simulation and assessment of the degradation of BESSs offering these services is presented, implementing a micro-cycle-based degradation algorithm and high-resolution data capture of number of cycles occurring at differing C-Rate and SOC ranges. The motivations and methodology behind the method are introduced and discussed and compared with existing methods. The impact of changing hybrid control schemes on battery degradation is introduced and discussed. The framework presented in this paper provides the foundation for further works analyzing the effect of varying control schemes and hybrid configurations on energy storage degradation.