Strategies for scaling-up LaNi5-based hydrogen storage system with internal conical fins and cooling tubes

Scaling-up of a 5 kg LaNi5 reactor i.e. Reference Design (RD) with 88.9 mm outer diameter (OD) and 10 conical copper fins embedded with 6 cooling tubes to a 25 kg one is studied through simulations. RD takes 585 s for 90% saturation during hydrogen absorption at Ps = 15 bar and 5 LPM water supply (20 °C). Decreasing tank OD and increasing the number of fins result in the best performance. A scaled-up design with tank OD = 114.3 mm and 60 fins exhibits 57–58% reduction in saturation time (695 s), versus a proportionally-scaled-up design (dimensions of RD increase proportionally) with tank OD = 141.3 mm and 10 fins. Five units of RD connected in series reduce saturation time by ~60% (670 s). Series/parallel configurations can match the RD performance, reduce shutdown risk, offer flexibility in operation, configuration and ease of maintenance.