Solid oxide electrolyzer cell including electrolysis-tolerant air-side electrode

Patent metadata

Field	Value
Publication number	US-2022190373-A1
Application number	US-202017120426-A
Country	US
Kind code	A1
Filing date	Dec 14, 2020
Priority date	Dec 14, 2020
Publication date	Jun 16, 2022
Grant date	—

Abstract

A solid oxide electrolyzer cell (SOEC) includes a solid oxide electrolyte, a fuel-side electrode disposed on a fuel side of the electrolyte, and an air-side electrode disposed on an air side of the electrolyte. The air-side electrode includes a barrier layer disposed on the air side of the electrolyte and containing a stabilized zirconia material having a lower electrical conductivity than an electrical conductivity of the electrolyte, and a functional layer disposed on the barrier layer.

First claim

What is claimed is:

1 . A solid oxide electrolyzer cell (SOEC) comprising:
a solid oxide electrolyte; a fuel-side electrode disposed on a fuel side of the electrolyte; and an air-side electrode disposed on an air side of the electrolyte, the air-side electrode comprising:
a barrier layer disposed on the air side of the electrolyte and comprising a stabilized zirconia material having a lower electrical conductivity than an electrical conductivity of the electrolyte; and
a functional layer disposed on the barrier layer.

2 . The SOEC of claim 1 , wherein:
the functional layer comprises at least 10 weight percent (wt %) electrically conductive material and at least 10 wt % ionically conductive material; the barrier layer comprises less than 1 atomic percent (at %) of the electrically conductive material; and the barrier layer has a lower electrical conductivity than the functional layer.

3 . The SOEC of claim 2 , wherein:
the ionically conductive material of the functional layer comprises a stabilized zirconia material; and the electrically conductive material comprises a metal or an electrically conductive metal oxide.

4 . The SOEC of claim 3 , wherein:
the stabilized zirconia material of the functional layer is stabilized with scandia, ceria, yttria, ytterbia, or any combination thereof; and the electrically conductive material comprises lanthanum strontium manganite.

5 . The SOEC of claim 4 , wherein:
the stabilized zirconia material of the barrier layer is stabilized with scandia, yttria, ytterbia, or any combination thereof; and the barrier layer comprises 0 to 0.5 at % of the electrically conductive material and 0 to 1 at % ceria.

6 . The SOEC of claim 1 , wherein the stabilized zirconia material of the barrier layer is represented by a formula: (ZrO 2 ) 0.9+y−x (Sc 2 O 3 ) 0.1−y (Y 2 O 3 ) x , wherein:
y ranges from 0 to 0.05, and x ranges from 0.01 to (0.05+y).

7 . The SOEC of claim 6 , wherein the stabilized zirconia material of the barrier layer is represented by the formula: (ZrO 2 ) 0.9−x (Sc 2 O 3 ) 0.1 (Y 2 O 3 ) x , wherein x ranges from 0.01 to 0.05.

8 . The SOEC of claim 7 , wherein the stabilized zirconia material of the barrier layer comprises (ZrO 2 ) 0.89 (Sc 2 O 3 ) 0.1 (Y 2 O 3 ) 0.01 .

9 . The SOEC of claim 6 , wherein the stabilized zirconia material of the barrier layer is represented by the formula: (ZrO 2 ) 0.91−x (Sc 2 O 3 ) 0.09 (Y 2 O 3 ) x , wherein x ranges from 0.01 to 0.06.

10 . The SOEC of claim 1 , wherein the stabilized zirconia material of the barrier layer is represented by a formula: (ZrO 2 ) 0.9+y−x (Sc 2 O 3 ) 0.1−y (Yb 2 O 3 ) x , wherein:
y ranges from 0 to 0.05, and x ranges from 0.01 to (0.05+y).

11 . The SOEC of claim 1 , wherein the stabilized zirconia material of the barrier layer is represented by a formula: (ZrO 2 ) 1−x (Y 2 O 3 ) x , wherein x ranges from 0.02 to 0.12.

12 . The SOEC of claim 11 , wherein the stabilized zirconia material of the barrier layer is represented by the formula: (ZrO 2 ) 1−x (Y 2 O 3 ) x , wherein x ranges from 0.08 to 0.11.

13 . The SOEC of claim 12 , wherein the stabilized zirconia material of the barrier layer comprises (ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 .

14 . The SOEC of claim 13 , wherein the functional layer comprises lanthanum strontium manganate and yttria stabilized zirconia represented by a formula: (ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 .

15 . The SOEC of claim 11 , wherein the stabilized zirconia material of the barrier layer is represented by the formula: (ZrO 2 ) 1−x (Y 2 O 3 ) x , wherein x ranges from 0.03 to 0.05.

16 . The SOEC of claim 1 , wherein:
the functional layer comprises lanthanum strontium manganate and yttria stabilized zirconia; and the barrier layer consists essentially of yttria stabilized zirconia having less than 1 at % lanthanum strontium manganate.

17 . The SOEC of claim 1 , wherein the air-side electrode further comprises an electrically conductive contact layer located on the functional layer.

18 . The SOEC of claim 1 , wherein the SOEC comprises a solid oxide regenerative fuel cell which is configured to alternately operate in a fuel cell mode and an electrolysis mode.

19 . A solid oxide electrolyzer cell (SOEC) stack, comprising:
interconnects; and a plurality of SOECs of claim 1 separated by the interconnects.

20 . The SOEC stack of claim 19 , wherein the SOEC stack is configured to alternately operate in a fuel cell mode and an electrolysis mode.

Assignees

• Bloom Energy Corp

Inventors

• Armstrong Tad

Classifications

• Y02E60/50

  Fuel cells · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M8/126

  the electrolyte containing cerium oxide · CPC title

• H01M8/1253

  the electrolyte containing zirconium oxide · CPC title