Optimization of Operating Conditions for an SOFC Stack

Abstract:

Performance testing for a single-cell solid oxide fuel cell (SOFC) stack is carried out to optimize its operating conditions. In this study, the Taguchi method is employed to effectively define the test matrix. The single-cell stack is composed of a 10x10 cm² commercial anode-supported cell, metallic interconnects, current collectors, and glass-ceramic sealant. The major parameters for the experiments include: flow rates of fuel (hydrogen) and oxidant (air) gases, and temperatures. The target indices are the electrical power output, electrical efficiency, and fuel utilization. The fuel flow rates (400, 500, and 600 sccm), air flow rates (1000, 1500, and 2000 sccm) and temperatures (650, 675, and 700°C) are evaluated for different experimental combinations. The results reveal that, the operating temperature is the most crucial factor to the stack performance. The maximum power reaches to 46 W (570 mW/cm²) with a current of 58 A (715 mA/cm²) at test conditions of 700°C and fuel and oxidant flow rates of 600 sccm and 2000 sccm, respectively. As the fuel flow rate decreases to 400 sccm, the electrical efficiency can reach to 53% while the power at 34.6 W (427 mW/cm²) and current 42 A (518 mA/cm²). As the current increases to 44 A (543 mA/cm²), the fuel utilization reaches to 83%, nevertheless concentration polarization is observed in such operating condition.

• Periodical: Key Engineering Materials (Volumes 656-657)
• Pages: 119-123
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.656-657.119
• Online since: July 2015
• Authors: Chang Wei Lu*, Szu Han Wu, Hung Hsiang Lin, Wen Hsiu Chung, Jing Kai Lin, Yung Neng Cheng, Ruey Yi Lee
• Keywords: Electrical Efficiency, Fuel Utilization, Solid Oxide Fuel Cell Stack, Taguchi Method

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