Fabrication and evaluation of a novel cathode-supported honeycomb SOFC stack

A novel solid oxide fuel cell (SOFC) stack based on a cathode-supported honeycomb SOFC single unit, capable of generating high volumetric power density, was fabricated. Facile connection of the honeycomb single units is achieved using a metal interconnect with a gastight conductive paste. The honeycomb single unit is designed to use the outer honeycomb face and the anode layer on the honeycomb edge face as the current collection paths for the cathode and anode sides, respectively. Current is conducted between the cathode of a single unit and the anode of an adjacent single unit through the metallic interconnect. A two-unit stack exhibited an open circuit voltage of approximately 2 V and twice the power of a single unit at 600 °C under wet H2 fuel flow. The volumetric power density of the honeycomb SOFC stack at 600 °C was calculated to be approximately 0.6 W/cm3.