Safety-intelligent metal hydride storage systems: Mechanistic modeling, optimization, and risk-based control

LaNi 5 -based metal hydrides present a promising alternative for hydrogen storage at lower pressures for on-board applications in fuel cell electric vehicles (FCEVs). However, these materials are prone to excessive core temperature peaks, resulting in safety hazards influenced by factors such as alloy composition, operating conditions, thermodynamics, and kinetics, which collectively impact operability and scalability. This study investigates thermal runaway in metal hydride storage systems (MHSS) during both charging and discharging processes to improve safety and operational performance. Open-loop analysis reveals that supply pressure and water flowrate significantly influence core temperature and hydrogen adsorption capacity during charging. During discharging, hydrogen discharge rate and water flowrate affect both the thermal response and the quantity of hydrogen desorbed. Consequently, the development and implementation of advanced control strategies are essential to balance the trade-offs between mitigating thermal runaway and maintaining system efficiency. A risk-based explicit model predictive control (R-eMPC) strategy was developed and validated through closed-loop simulations under various scenarios to assess its effectiveness in reducing risk and extending operational duration. The R-eMPC exhibits minimal peak overshoot of core temperature while achieving the maximum hydrogen storage and discharge capacity within the specified horizon. Therefore, the findings indicate that integrating risk-aware control offers a proactive solution for enhancing the safety and reliability of metal hydride on-board storage in FCEVs.