Fuel cell

Patent metadata

Field	Value
Publication number	US-2018131007-A1
Application number	US-201815862277-A
Country	US
Kind code	A1
Filing date	Jan 4, 2018
Priority date	Jul 7, 2015
Publication date	May 10, 2018
Grant date	—

Abstract

The fuel cell according to the present invention has an anode, a cathode and a solid electrolyte layer. The cathode contains a perovskite oxide as a main component. The perovskite oxide is expressed by the general formula ABO 3 and including La and Sr at the A site. The solid electrolyte layer is disposed between the anode and the cathode. The cathode has a surface on opposite side to the solid electrolyte layer. A first ratio of a Sr concentration relative to an La concentration is less than or equal to 4 times a second ratio of the Sr concentration relative to the La concentration. The first ratio is detected by use of X-ray photoelectron spectroscopy on the surface of the cathode. The second ratio of a Sr concentration relative to a La concentration is detected by use of X-ray photoelectron spectroscopy on an exposed surface. The exposed surface is exposed by surface processing of the surface. The exposed surface is positioned within 5 nm of the surface in relation to a direction of thickness.

First claim

What is claimed is:

1 . A fuel cell comprising;
an anode, a cathode containing a perovskite oxide as a main component, the perovskite oxide expressed by the general formula ABO 3 and including La and Sr at the A site, and a solid electrolyte layer disposed between the anode and the cathode, the cathode having a surface on opposite side to the solid electrolyte layer, and a first ratio of a Sr concentration relative to an La concentration being less than or equal to 4 times a second ratio of the Sr concentration relative to the La concentration, the first ratio being detected by use of X-ray photoelectron spectroscopy on the surface of the cathode, the second ratio of a Sr concentration relative to a La concentration being detected by use of X-ray photoelectron spectroscopy on an exposed surface, the exposed surface being exposed by surface processing of the surface, the exposed surface being positioned within 5 nm of the surface in relation to a direction of thickness.

2 . The fuel cell according to claim 1 , wherein the first ratio is greater than or equal to 1.0 the second ratio.

3 . The fuel cell according to claim 1 , wherein a total amount of Ba, Ca, Na and K in the A site of the perovskite oxide is less than or equal to 2000 ppm.

Assignees

• Ngk Insulators Ltd

Inventors

• Fujisaki Shinji
• Yamamura Yoshihiko
• Ryu Takashi
• Ohmori Makoto

Classifications

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• C04B2235/3275

  Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite · CPC title

• C04B2235/3213

  Strontium oxides or oxide-forming salts thereof · CPC title

• C04B35/2608

  Compositions containing one or more ferrites of the group comprising manganese, zinc, nickel, copper or cobalt and one or more ferrites of the group comprising rare earth metals, alkali metals, alkaline earth metals or lead · CPC title

• C04B2235/72

  Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics · CPC title