Flame Deposition of the Electrolyte and Cathode for High and Stable Performance of Low-Temperature SOFCs

The key obstacles to the development of low operating temperature (LT) SOFCs are high ohmic resistance and high electrode overpotentials. In the present work, we demonstrate excellent cell performance at 600 °C on a anode supported bi-layer electrolyte SOFC having a thin RSDT-made cerium gadolinium oxide (Gd0.2Ce0.8O2−δ, CGO) and a lanthanum strontium cobaltite (La0.6Sr0.4CoO3−δ, LSC) perovskite cathode. The measured ohmic resistance of the ASE cell with CGO layer deposited by RSDT was 0.24 ohm.cm2, which is close to the expected theoretical value of 0.17 ohm.cm2 for a 5 micron thick 8YSZ electrolyte at 600 °C. This indicates that the obtained peak power output density is approaching what is theoretically possible. This work is based on the lab scale use of Reactive Spray Deposition Technology (RSDT) which is an open atmosphere, cost efficient technique that does not require high vapor precursors and is an effective way to deposit thin ceramic layers of YSZ/CGO/LSC onto Ni-YSZ substrates. It has the potential to chain successive coating steps thus, significantly simplifying the production of multilayered ceramic structures as the SOFCs and reducing the cost associated with manufacturing of the cells.

Lack of electrical interaction between proximal bundle branches and subjacent muscle

Microelectrode techniques were used to assess the importance of subthreshold electrotonic interactions between the canine proximal bundle branches and adjacent septal myocardium, and vice versa. Bundle branch action potential duration, maximal rising velocity of phase O, current threshold requirements for all-or-none depolarization, transmembrane voltage, and spontaneous frequency were not altered by adjacent septal muscle activation. Activation of the proximal bundle branches did not change the transmembrane voltage of immediately subjacent muscle cells; likewise, all-or-none activation of ventricular septal muscle did not effect a voltage change in the overlying proximal bundle branches. We conclude that a high ohmic resistance barrier between proximal bundle branch and subjacent muscle precludes significant electrotonic interactions between these neighboring structures.