A Danish-Norwegian research team claims to have developed a metal-based monolithic SOFC (solid oxide fuel cell) suited for transportation applications. Because of the high temperature at which SOFCs can function, they are commonly used for stationary applications, such as combined heat as well as power systems, according to the researchers. Due to their reduced power density and the restricted thermal cycling resilience of their ceramic anode, these devices are generally deemed less suited for cars.
The ceramic anode was substituted with metallic interconnects in the proposed fuel cell architecture. “The monolith concept combines the gas channels, cell support, and interconnects into a single layer, resulting in a 2–4 reduction in stack height,” the researchers noted, adding compared to the metal-centered monolith stack is substantially less expensive than a conventional stack. “This significantly improves the volumetric density and precise power of the stack, both of which are critical metrics in vehicles due to space and weight constraints.”
Furthermore, the SOFC’s high metal content is reported to reduce temperature variations throughout the stack and provide greater resistance to quick thermal cycles during operation, which the researchers believe could be essential when integrating the fuel cell alongside electric batteries in a car. “Prior work on monolithic SOFCs designs was reported by Saint-Gobain, which built entirely ceramic monolithic SOFC stacks, and Argonne National Laboratory, which designed metal-supported SOFC stacks (‘TuffCell’),” according to the study group. “However, when compared to the one produced by Argonne National Laboratory, our model of metal-based monolithic SOFCs contains some major distinctions, such as processing techniques to incorporate gas flow channels, electrode materials plus thicknesses, and the principle of integrated sealing.”
Four methods – co-sintering, catalyst infiltration, tape casting, and lamination – were used to create a monolith SOCF featuring an active cell size of roughly 18 cm2, which the scientists described as conventional techniques used in fuel cell manufacture. The device was discovered to possess an open-circuit voltage of about 1065mV as well as a 5.6 kW/L, its power density, which the researchers claim is comparable to the best ceramic anode fuel cells. “We predict that this concept, or one similar to it,” they concluded, “may enable large-scale manufacture of electric vehicles propelled by fuel cells with significantly greater range, reduced charging periods, and cheaper cost.”
The fuel cell technology is described in the Nature Communications paper titled Production of a monolithic fuel cell stack with excellent power density. Academics from the Technical University of Denmark and Sintef, a Norwegian research organization, are part of the research team.