Solid oxide fuel cell

Patent metadata

Field	Value
Publication number	US-10056620-B2
Application number	US-201414304434-A
Country	US
Kind code	B2
Filing date	Jun 13, 2014
Priority date	Dec 19, 2011
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

A solid oxide fuel cell includes a cathode, and an anode, and a solid electrolyte layer disposed between the cathode and the anode. The cathode includes a complex oxide having a perovskite structure expressed by the general formula ABO3. A standard deviation value for the atomic percentage of respective elements at the A site measured using energy dispersive X-ray spectroscopy at 10 spots in a single field on the sectional surface of the cathode is no more than 10.4.

First claim

What is claimed is:

1. A solid oxide fuel cell comprising:
a cathode including a complex oxide having a perovskite structure expressed by the general formula ABO 3 , wherein the A site includes at least one of lanthanum and strontium, and the B site includes at least one of cobalt, iron and nickel;
an anode; and
a solid electrolyte layer disposed between the cathode and the anode,
the cathode including at least one additive in such an amount that a standard deviation value for an atomic percentage of each respective element at the A site measured using energy dispersive X-ray spectroscopy at 10 spots in a single field on a sectional surface of the cathode is no more than 10.4, the cathode including a cathode material having a uniform composition distribution throughout the cathode material including an outer surface and an inner body of the cathode material, and
the single field being within a range observed by an electron microscope with a magnification of 100 times to 5000 times.

2. The solid oxide fuel cell according to claim 1 , wherein
a standard deviation value for the atomic percentage of respective elements at the B site measured using energy dispersive X-ray spectroscopy at 10 spots in a single field is less than or equal to 5.03.

3. The solid oxide fuel cell according to claim 1 , wherein
at least one atom of Co and Fe is included at the B site.

4. The solid oxide fuel cell according to claim 1 , wherein
the complex oxide is (La, Sr)(Co, Fe)O 3 , (La, Sr) FeO 3 , (La, Sr)CoO 3 , or La(Ni, Fe)O 3 .

5. The solid oxide fuel cell according to claim 1 , wherein
an analysis spot size of each of the 10 spots is less than or equal to 1 micrometer.

6. The solid oxide fuel cell according to claim 1 , wherein
the position of the 10 spots is selected from the single field on the basis of the concentration level in 10 stages determined in response to a distribution of the atomic percentage in the single field.

7. The solid oxide fuel cell according to claim 6 , wherein
the concentration level of the 10 stages is set across an entire range of the distribution of the atomic percentage in the single field.

8. The solid oxide fuel cell according to claim 1 , wherein
the complex oxide includes at least Fe at the B site.

9. The solid oxide fuel cell according to claim 1 , wherein
the at least one additive is selected from the group consisting of phosphorus, chromium and boron.

10. The solid oxide fuel cell according to claim 1 , wherein
the at least one additive is selected from the group consisting of P, Cr, B, Na, Mg, Al, Si, Ca, Sc, Ti, Ni, Zn, Y, Zr, Ba, Ce and Gd.

11. A solid oxide fuel cell comprising:
a cathode including a complex oxide having a perovskite structure expressed by the general formula ABO 3 , wherein the A site includes at least one of lanthanum and strontium, and the B site includes at least one of cobalt, iron and nickel;
an anode; and
a solid electrolyte layer that is disposed between the cathode and the anode,
the cathode including at least one additive in such an amount that a standard deviation value for the atomic percentage of each respective element at the B site measured using energy dispersive X-ray spectroscopy at 10 spots in a single field on a sectional surface of the cathode being less than or equal to 5.03, the cathode including a cathode material having a uniform composition distribution throughout the cathode material including an outer surface and an inner body of the cathode material, and
the single field being within a range observed by an electron microscope with a magnification of 100 times to 5000 times.

Assignees

• Ngk Insulators Ltd

Inventors

• Ohmori Makoto
• Kobayashi Ayano
• Fujisaki Shinji

Classifications

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• B01J23/83

  with rare earths or actinides · CPC title

• C04B35/26

  based on ferrites · CPC title

• C04B2235/3213

  Strontium oxides or oxide-forming salts thereof · CPC title

• B01J27/188

  with chromium, molybdenum, tungsten or polonium · CPC title