Micro solid oxide fuel cell fabricated on porous stainless steel: a new strategy for enhanced thermal cycling ability

Miniaturized solid oxide fuel cells (micro-SOFCs) are being extensively studied as a promising alternative to Li batteries for next generation portable power. A new micro-SOFC is designed and fabricated which shows enhanced thermal robustness by employing oxide-based thin-film electrode and porous stainless steel (STS) substrate. To deposit gas-tight thin-film electrolyte on STS, nano-porous composite oxide is proposed and applied as a new contact layer on STS. The micro-SOFC fabricated on composite oxide- STS dual layer substrate shows the peak power density of 560 mW cm−2 at 550 °C and maintains this power density during rapid thermal cycles. This cell may be suitable for portable electronic device that requires high power-density and fast thermal cycling.1111Ysciescopu

Low-temperature fabrication of protonic ceramic fuel cells with BaZr0.8Y0.2O3-δ electrolytes coated by aerosol deposition method

To overcome the difficulties of sintering yttrium (Y)-doped barium zirconate (BZY), an aerosol deposition (AD) method is suggested as an attractive alternative since it produces dense BZY films in commercially large areas with high deposition efficiency at low temperature. In this study, highly Y-doped BZY powder for use in AD method was synthesized successfully without use of sintering additives; the process involves a series of careful preparation processes including pre-doping of Y, high-energy milling, and calcination with an atmospheric powder which maintains controlled BaO vapour pressure. It is noted that Y-doping of BaZrO3 in starting powder is important in the AD method. The increased conductivity of BZY electrolyte film using this powder resulted in relatively small Ohmic resistance (similar to 0.5 Omega cm(2) at 700 degrees C) and good cell performance (similar to 180 mW cm(-2) at 700 degrees C). These are one of the best performance among the reported values of cells that employ BaZr0.8Y0.2O3-delta (or BZY20) as an electrolyte. The high performance is also remarkable although the firing temperature of this cell (1200 degrees C) is much lower than those (>= 1400 degrees C) shown in literature studies. The performance can be further improved with appropriate choice of cathode and anode materials. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.X111512sciescopu

Printable Solid Electrolyte Interphase Mimic for Antioxidative Lithium Metal Electrodes

Despite the ever-growing demand for Li metals as next-generation Li battery electrodes, little attention has been paid to their oxidation stability, which must be achieved for practical applications. Here, a new class of printable solid electrolyte interphase mimic (pSEI) for antioxidative Li metal electrodes is presented. The pSEI (approximate to 1 mu m) is directly fabricated on a thin Li metal electrode (25 mu m) by processing solvent-free, UV polymerization-assisted printing, exhibiting its manufacturing simplicity and scalability. The pSEI is rationally designed to mimic a typical SEI comprising organic and inorganic components, in which ethoxylated trimethylolpropane triacrylate and diallyldimethylammonium bis(trifluoromethanesulfonyl)imide are introduced as an organic mimic (acting as a moisture-repellent structural framework) and inorganic mimic (allowing facile Li-ion transport/high Li+ transference number), respectively. Driven by the chemical/architectural uniqueness, the pSEI enables the thin Li metal electrode to show exceptional antioxidation stability and reliable full cell performance after exposure to humid environments

Nanofibrous Conductive Binders Based on DNA-Wrapped Carbon Nanotubes for Lithium Battery Electrodes

In contrast to enormous progresses in electrode active materials, little attention has been paid to electrode sheets despite their crucial influence on practical battery performances. Here, as a facile strategy to address this issue, we demonstrate nanofibrous conductive electrode binders based on deoxyribonucleic acid (DNA)-wrapped single-walled carbon nanotubes (SWCNT) (denoted as DNA@SWCNT). DNA@SWCNT binder allows the removal of conventional polymeric binders and carbon powder additives in electrodes. As a proof of concept, high-capacity overlithiated layered oxide (OLO) is chosen as a model electrode active material. Driven by nanofibrous structure and DNA-mediated chemical functionalities, the DNA@SWCNT binder enables improvements in the redox reaction kinetics, adhesion with metallic foil current collectors, and chelation of heavy metal ions dissolved from OLO. The resulting OLO cathode exhibits a fast charging capability (relative capacity ratio after 15 min [versus 10 h] of charging = 83%), long cyclability (capacity retention = 98% after 700 cycles), and thermal stability