Microtubular SOFCs

Sammes N.M., Du Y., Bove R. (2005) Design and fabrication of a 100 W anode supported microtubular SOFC stack. Journal of Power Sources 145, 428 434. 

Hashimoto, S., Nishino, H., Uu, Y., Asano, K., Mori, M., Furahashi, Y., and Fujishiro, Y. (2008) Effects of pressurization on cell performance of a microtubular SOFC with Sc-doped zirco-nia electrolyte. /. Bectrochem. Soc., 155, B587-B591. 

Microtubular SOFCs have been successfully integrated into portable power xmits by Ultra Electronics AMI (USA). Figure 8 shows its 50 W and 250 W systems that use propane as the fuel to produce continuous power. The 50 W systems, miming on propane, provide power for ground sensors, unmanned aerial vehicles, and robots. The 250 W systems are fueled by propane or LPG and are used to extend military mission durations and deliver off-grid power for electronics, radios, and computers. The use of globally available fuels in such portable SOFC systems eliminates complicated logistics. 

Acumentrics Corp. USA 2kW 2002 Microtubular SOFCs, 2kW for uninterruptible power... 

The second major benefit of the microtubular design is a high thermal shock resistance [41]. Whereas the large-diameter tubular SOFCs are prone to cracking if they are rapidly heated, the microtubular SOFCs do not crack even when heated in a blow torch to their operating temperature of about 850°C in as little as 5 s. This is a marked advantage in applications where start-up time is critical. 

A typical design of a microtubular SOFC is shown in Figure 8.25. A YSZ electrolyte tube (typically 2 mm in diameter and about 150 pm wall thickness), is used as a support for the electrodes, as a gas inlet tube, and also as a combustor tube at its outlet. The overall length of the tube is between 100 and 200 mm, whereas the cell region only occupies a length of about 30 mm towards the outlet end of the tube. The Ni + YSZ anode, 30 mm long, is coated on the inner wall of... 

Microtubular SOFCs have also been effectively used to test the operation of SOFCs on various hydrocarbon fuels. A significant benefit of the microtubular... 

Microtubular SOFCs, 2 kW systems for uninterruptible power Microtubtilar, rapid start-up and cyclable... 

In March 2013, Advanced Manufacturing Research Unit (AIST) in Japan announced the release of a portable SOFC that can operate on a range of liquid fuels. It is a microtubular SOFC technology the system can directiy use... 

Single-Step Formation of Triple-Layer Membranes for Microtubular SOFC... 

Othman, M.H.D. et al., High-Performance, Anode-Supported, Microtubular SOFC Prepared from Single-Step-Fabricated, Dual-Layer Hollow Fibers. Advanced Materials, 2011.23(21) 2480. 

For a more economical fabrication of microtubular SOFC with more reliability and flexibility in quality control, an advanced dry-jet wet extrusion technique, that is, a phase inversion-based co-extrusion process, followed by co-sintering and reduction processes was employed to fabricate a novel electroly te/anode dual-layer hollow fiber. Using the co-extrusion technique, one of the layers has to be thick in order to provide mechanical strength to the fiber, and in this design, the anode is chosen to be the thick layer due to the much lower ohmic losses (as shown in Figure 11.16). Use of co-extrusion has many advantages over conventional dry-jet wet extrusion methods such as simplified fabrication and better control over the manbrane structure. Furthermore, the risk of defects formation can be reduced and at the same time greater adhesion between the layers can be achieved. 

FICURE11.23 Experimental apparatus of the single microtubular SOFC reactor. 

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