A Mission-Based Co-Design Optimization Framework for Hybrid Battery Fuel Cell Marine Power Systems

Abstract

Hybrid energy storage systems combining a fuel cell system (FCS) with high-energy (HE) and high-power (HP) batteries are a promising pathway toward low-emission marine power systems. However, system performance is strongly influenced by the coupled interaction between component sizing and energy management system (EMS) behavior under mission-dependent load dynamics. This paper proposes a simulation-based multi-objective co-design optimization framework that jointly optimizes the sizing of a modular HE/HP battery architecture, the rated fuel cell power (in discrete modular steps), and key EMS parameters within a unified MATLAB/Simulink loop using NSGA-II. The optimization targets three conflicting objectives: capital expenditure (CAPEX), hydrogen-based operational expenditure (OPEX), and average fuel cell efficiency, while enforcing mission feasibility and operational constraints, including battery state-of-charge bounds and fuel cell ramp-rate limitations. The results highlight a clear trade-off between investment cost, hydrogen consumption, and fuel cell efficiency. Selected solutions show reduced hydrogen consumption and improved fuel cell efficiency at the expense of higher system cost. A representative knee-point solution provides a balanced compromise, ensuring efficient fuel cell operation with reduced dynamic stress and effective power sharing between high-energy and high-power batteries. Overall, the proposed codesign framework provides a quantitative basis for selecting balanced hybrid battery-fuel cell architectures tailored to marine mission profiles and highlights the necessity of jointly optimizing system sizing and EMS parameters.