Five‐layer reverse tape casting of IT‐SOFC

Abstract

Tape casting is a well‐established method for manufacturing thin ceramic layers with controllable thickness and porosity. This study investigates the potential of 10Sc1CeSZ material for the electrolyte and anode layers for intermediate‐temperature solid oxide fuel cells (IT‐SOFC) in an anode‐supported cell (ASC) geometry. In order to use La0.6Sr0.4Co0.2Fe0.8 Oxide (LSCF) cathode material, a Gd0.2Ce0.8 Oxide (GDC) barrier layer is needed; however, thermal expansion coefficient mismatch results in delamination of the GDC from the electrolyte during high temperature sintering when fabricated by conventional tape casting procedures. For the first time, ASCs have been manufactured by a five‐layer tape casting technique; barrier layer, novel composite layer, electrolyte, anode functional layer, and anode substrate. Ni‐ScCeSZ composite cells were tested between 650 and 800°C in H2:N2 fuel (85% H2) on the anode and air on the cathode to yield a maximum power density of .46 W/cm2. These results demonstrate the feasibility of this new five‐layer tape casting technique to produce IT‐SOFC.

Planar Solid Oxide Fuel Cell Fabricated by Aqueous Reverse Sequential Tape‐Casting of the Anode, Electrolyte, and Barrier Layer

“…PVA is selected as a binder and PEG400 as a plasticizer to decrease the glass temperature transition of PVA and increase the flexibility of the tape by breaking the close alignment and bonding of PVA chains. [11,14,14,27] PEG400 was used with a 1:1 plasticizer to binder ratio. Slurries were achieved by mixing the suspension with PVA and PEG400 in the planetary centrifugal mixer at 1000 rpm during 7 min and at 2000 rpm during 2 min and the excess of bubbles was outgassed in the machine during 2 min at 2000 rpm.…”

“…To solve that, researches of nontoxic and aqueous-based slurries have been developed and show that, to counterbalance the polarity of water molecules, the use of acrylic latex commercial emulsion or polyvinyl alcohol (PVA) as binder allows optimizing slurry dispersion and stability. [11][12][13][14][15] Following these principles, Snowdon et al successfully produced an anodic half-cell including the DBL layer by sequential tape-casting. [14] Slurries were composed of oxide powders of NiO-ScCeSZ for anode, ScCeSZ for electrolyte, and a 10GDC (Ce 0.9 Gd 0.1 O 2 ) as diffusion barrier layer but only the anode slurry was aqueous with a PVA binder, the others were composed of commercial binder solutions which are expensive and with a nonadjustable composition.…”

“…[11][12][13][14][15] Following these principles, Snowdon et al successfully produced an anodic half-cell including the DBL layer by sequential tape-casting. [14] Slurries were composed of oxide powders of NiO-ScCeSZ for anode, ScCeSZ for electrolyte, and a 10GDC (Ce 0.9 Gd 0.1 O 2 ) as diffusion barrier layer but only the anode slurry was aqueous with a PVA binder, the others were composed of commercial binder solutions which are expensive and with a nonadjustable composition.…”

“…To solve that, researches of nontoxic and aqueous‐based slurries have been developed and show that, to counterbalance the polarity of water molecules, the use of acrylic latex commercial emulsion or polyvinyl alcohol (PVA) as binder allows optimizing slurry dispersion and stability. [ 11–15 ]…”

A review on materials, advantages, and challenges in thin film based solid oxide fuel cells

“…The conventional techniques for fabricating SOFC components at the macro scale are dry pressing, 74,75 tape casting, 49,[76][77][78][79][80][81][82] slip casting, 83,84 screen printing, [85][86][87] dip coating, [88][89][90] and spin coating. 91,92 Many industries use to employ tape casting as a major fabrication tool for large scale production of SOFCs.…”