A hybrid power-unit based on a passive fuel cell/battery system for lightweight vehicles. (1st December 2020)

• Record Type: Journal Article
• Authors: Di Trolio, P.; Di Giorgio, P.; Genovese, M.; Frasci, E.; Minutillo, M.
• Is Part Of: Applied energy. Volume 279(2020)
• Publication Date: 2020-12-01
• Subjects: Hydrogen Mobility -- Passive hybrid fuel cell/battery power unit -- Experimental analysis -- Numerical analysis -- ARTEMIS drive cycle; Power (Mechanics) -- Periodicals; Energy conservation -- Periodicals; Energy conversion -- Periodicals; 621.042
• DOI: 10.1016/j.apenergy.2020.115734
• Languages: English
• ISSNs: 0306-2619

Abstract

Highlights: A novel hybrid power-unit based on a passive fuel cell/battery system is proposed. The hybrid power-unit consists of 5 fuel cell stacks and 6 battery modules. A dedicated test bench has been realized for reproducing the Artemis duty-cycle. The fuel cell unit produces about the 51% of the energy request by the load. The average efficiency of the fuel cell unit during the Artemis duty-cycle is 47%. Abstract: Hybrid fuel cell/battery power-unit configurations are gaining growing attention; in fact, they offer advantages in terms of fuel cell downsizing, higher efficiency and fast fueling. In these configurations, the power-sharing is actively controlled employing power electronics, mainly boost converters, that affect the costs and performance of the system. In this work, a novel hybrid power-unit based on a passive fuel cell/battery system is proposed for a lightweight electric vehicle (5 kW nominal power). This configuration eliminates the need for costly power converters, and increases the overall performance. The hybrid power-unit consists of 5 fuel cell stacks, 6 battery modules and two resistors that allow safe fuel cell start-up and shut-down. The power profile requested by the electric motor is derived from an ARTEMIS drive cycle and tested by means of two electronic loads. The analysis on the power-unit behavior and performance has been carried out by means of a numerical model and experimental activities. The power-unit response has been analyzed focusing on: i) start-up operation; ii) drive cycle operation; iii) shut-down operation. During the whole test, the fuel cell produced about 51% of the total requested energy while the battery pack about 49%. The average stack efficiency during operation resulted to be 47%, while it dropped to 41% considering also start-up and shut-down. Results proved the technical feasibility as well as the safety of the system and showed that the developed power-unit has promising features for practical applications.