Low Temperature Performance Improvement of SOFC with Thin Film Electrolyte and Electrodes Fabricated by Pulsed Laser Deposition

Abstract

The performance of solid oxide fuel cells (SOFCs) with thin film electrolytes and electrodes was investigated at a lower operating temperature regime (T≤600°C) . 2×2cm anode-supported unit cells with thin film components of a Ni–yttria-stabilized zirconia (YSZ) composite anode interlayer, a thin (≤1μm) YSZ electrolyte, and a lanthanum strontium cobalt oxide cathode were fabricated by using pulsed laser deposition, and the performance of the cells was characterized at the temperature range of 350°C≤T≤600°C . Stable open-circuit voltage values above 1 V were successfully obtained with thin film electrolyte cells, which implied that the 1μm thick electrolyte was fairly dense and gastight. The thin film electrolyte cells exhibited a much more improved cell performance than a thick film (∼8μm) YSZ electrolyte cell at the low operating temperature regime (350–550°C) and, in some cases, showed better power outputs than other thin film membrane micro-SOFCs.

Direct Applicability of La0.6Sr0.4CoO3 – δ Thin Film Cathode to Yttria Stabilised Zirconia Electrolytes at T ≤ 650 °C

“…Recently, much attention has been paid to develop micro-SOFCs for next generation portable and mobile power sources since the merits of SOFCs such as high efficiency and fuel flexibility are very intriguing properties for portable power sources also [1][2][3][4][5]. To realise micro-SOFCs for portable applications, size reduction and operating temperature decrease should be accomplished.…”

“…Especially, the latter is an important task for cutting down the burden in the thermal management of an integrated power pack, as well as for improving the reliability of the cell and the stack by preventing reaction between components. Although cutting down the Ohmic resistance by using thin film electrolytes is the most commonly sought approach to lower the operating temperature of SOFCs [1,[3][4][5][6], reducing polarisation losses at the lower temperature range is still a significant issue to be solved [7]. Therefore, cathode materials with high mixed ionic and electronic conducting (MIEC) properties like lanthanum strontium cobalt oxide (LSC) and other cobalt containing cathodes were studied for the lower temperature operation of SOFCs [7,8].…”

Solid oxide fuel cell anode surface modification by magnetron sputtering of NiO/YSZ thin film

“…Formation of the nanostructured anode functional layer (AFL) will lead to an increase of the TPB length of an anode and to a decrease of activation polarization of the anode [7]. Among many methods used to prepare the anode functional layer, the greatest success in terms of the nanostructures formation was achieved by methods of physical vapor deposition (PVD), such as pulsed laser deposition [8], magnetron sputtering [9,10], electron beam evaporation [11] and others. Among all, magnetron sputtering is characterized by several advantages.…”

Yttria and ceria doped zirconia thin films grown by pulsed laser deposition

“…The YSZ is a standard electrolyte for SOFCs, which are potential candidates for next generation portable and mobile power sources [3][4][5][6][7][8][9][10] . Standard YSZ electrolytes operate at high temperatures (800-1000 °C) due to their ionic conductivity properties which become efficient enough only at this temperature range.…”

“…Decreasing the operational temperature decreases the YSZ ionic conductivity, but this can be compensated by reducing the thickness of the electrolyte, and thus reducing ohmic losses 4,[6][7][8][9][10][11][12] . Thin and dense YSZ electrolytes can be fabricated by different techniques such as physical or chemical vapor deposition (PVD, CVD), plasma enhanced CVD (PECVD), sol-gel method, electrochemical vapor deposition, suspension or atmospheric plasma spraying [13][14] , pulsed laser deposition (PLD) 15 , etc.…”