Design of industrially scalable microtubular solid oxide fuel cells based on an extruded support

Abstract

The current work describes the adaptation of an existing lab-scale cell production method for an anode supported microtubular solid oxide fuel cell to an industrially ready and easily scalable method using extruded supports. For this purpose, Ni-YSZ (yttria stabilized-zirconia) anode is firstly manufactured by Powder Extrusion Moulding (PEM). Feedstock composition, extruding parameters and binder removal procedure are adapted to obtain the tubular supports. The final conditions for this process were: feedstock solid load of 65 vol%; a combination of solvent debinding in heptane and thermal debinding at 600 °C. Subsequently, the YSZ electrolyte layer is deposited by dip coating and the sintering parameters are optimized to achieve a dense layer at 1500 0 C during 2 hours. For the cathode, a LSM (lanthanum strontium manganite)-YSZ layer with an active area of 1 cm 2 is deposited by dip coating. Finally, the electrochemical performance of the cell is measured using pure humidified hydrogen as fuel. The measured power density of the cell at 0.5V was 0.7Wcm-2 at 850 0 C.

The influence of the reducing conditions on the final microstructure and performance of nickel-yttria stabilized zirconia cermets

“…Final dimensions of the cells are 50 mm in length; wall thickness of ∼700 μm; outer diameter of 3.2 mm; electrolyte thickness of ∼20 μm; and total cathode thickness of ∼35 μm. Additional details of the fabrication process can be found in references [26] and [27]. Chronoamperometric studies and Electrochemical Impedance Spectroscopy (EIS) studies were subsequently performed.…”

Tailoring the Microstructure of a Solid Oxide Fuel Cell Anode Support by Calcination and Milling of YSZ

“…Anode porosity has been found to be an important factor in cell microstructure and thus power performance. Porosities in the range of 50 vol.% for the anode supported microtubular cells are typically used10. Suzuki et al 11.…”

Highly stable microtubular cells for portable solid oxide fuel cell applications

“…Final composition of the anode support was adjusted to a Ni-YSZ ratio of 50:50 (% in volume of solid phase), and porosities in the range of 50%. Additional details about the extrusion process, as well as the debinding process to eliminate the organic load, are shown in reference [7] and [24]. Subsequently YSZ was deposited as the electrolyte and co- For the electrochemical studies, microtubular cells were sealed into alumina tubes using ceramic sealing and then introduced in a three-zone tubular furnace with a homogeneous hot zone of 5 cm in length.…”

“…One of the key parameters is to achieve strong interfaces between the different components and thus reducing polarization losses of the cells. For that purpose, different fabrication methods for the tubular supports were reported, such as cold isostatic pressing [4,5], powder extrusion moulding (PEM) [6,7,8], powder injection moulding (PIM) [9], gel-casting [10,11], slip-casting [12,13] or the immersion-induced inversion method [14,15]. Currently, the state of the art configuration for microtubular cells is the use on anode supported cells, and the most used composition is nickel-YSZ [2,3].…”

“…Extruded support tubes based on Nickel Oxide-YSZ (yttria stabilizedzirconia) were recently manufactured by Powder Extrusion Moulding (PEM) [7]. Feedstock composition and extruding parameters were adjusted to obtain highly reproducible tubular green bodies, followed by deposition of the electrolyte (YSZ) and cathode (Lanthanum Strontium Manganite LSM/ YSZ) [24].…”