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St. Andrews Fuel Cells Ltd. is a spin-off company (formed in February 2005) from the University of St. Andrews. The company’s focus is on the development of the SOFCRoll fuel cell. The SOFCRoll design is produced from tape casting and is fired in a single unit, offering reduced fuel cell production costs. Additionally, the self-supporting nature of the SOFCRoll geometry removes the need for thick cell components, further reducing cell cost and offering increased power densities. This paper reviews the development of the SOFCRoll concerning the processing and performance testing.

The Solid Oxide Fuel Cell Roll (SOFCRoll) is a novel design based on a double spiral. Combining structural advantages of tubular geometries with processing advantages of thick film methods, it utilises a single cofiring process. The initial concept used separate tape cast layers which were laminated before rolling. To optimise layer thickness to function, thinner screen printed layers were combined into the tape cast structure in 2nd generation cells. This presented several processing challenges, such as achieving dense electrolyte layers, maintaining porous electrode and current collecting layers and incorporation of integral gas channels. Performance has been promising with open circuit voltages close to 1V and cell power of over 400mW at 800°C, however cracking is still evident. Therefore further iterations are in development where thinner layers are sequentially cast, aiming to improve interfacial bonding and better match plasticity and burn out to reduce cracking. This paper reviews key aspects of understanding and development of the SOFRoll , the challenges that have been tackled and what challenges remain, along with future directions for development and potential applications for this device.

Rolled tubular solid oxide fuel cells are manufactured in a low-cost single step firing process, so the design offers reduced production cost. All components are produced using a low cost tape casting method and are fired as a single unit. The geometry is self–supporting which removes the need for thick cell components further reducing cell cost and offering increased volumetric power densities. Here we present the results from some early studies on the influence of fast thermal cycling on performance characteristics. Thermal cycles were carried out heating and cooling at 10 °C min−1 between 400 and 800 °C. Less than 1% performance drop was calculated for the single cell and 5% drop was observed on the fourth cycle for the five cell bundle.

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