Wet seal caulk with enhanced chemical resistance

Patent metadata

Field	Value
Publication number	US-2020395622-A1
Application number	US-202017008127-A
Country	US
Kind code	A1
Filing date	Aug 31, 2020
Priority date	Mar 8, 2018
Publication date	Dec 17, 2020
Grant date	—

Abstract

A caulk composition includes: at least one powder component and at least one binder component. The powder component is a ball-milled powder component comprising ceria, zirconia, alumina, or a combination thereof. The powder component is a heat-treated powder component that has been heated to a temperature of at least 1500° C. The powder component is present in a concentration range of 65 wt % to 75 wt % of the caulk composition. The powder component has a particle size distribution of 95% less than 25 μm and 90% greater than 1 μm. The binder component is present in a concentration range of 25 wt % to 35 wt % of the caulk composition.

First claim

What is claimed is:

1 . A caulk composition comprising:
at least one powder component, wherein:
the powder component is a ball-milled powder component comprising ceria, zirconia, alumina, or a combination thereof,
the powder component is a heat-treated powder component that has been heated to a temperature of at least 1500° C.,
the powder component is present in a concentration range of 65 wt % to 75 wt % of the caulk composition, and
the powder component has a particle size distribution of 95% less than 25 μm and 90% greater than 1 μm; and
at least one binder component, wherein the binder component is present in a concentration range of 25 wt % to 35 wt % of the caulk composition.

2 . The caulk composition of claim 1 , wherein the powder component is zirconia.

3 . The caulk composition of claim 1 , wherein the binder component comprises at least one of ceria or zirconia.

4 . The caulk composition of claim 3 , wherein the binder component is zirconia.

5 . The caulk composition of claim 1 , further comprising pores having a pore diameter in a range of about 1 nm to about 50 nm.

6 . The caulk composition of claim 1 , further comprising pores having a cumulative pore area of at most about 1 m 2 /g.

7 . The caulk composition of claim 1 , wherein the at least one powder component and the at least one binder component do not include ceria.

8 . A molten carbonate fuel cell (MCFC) comprising:
a fuel cell stack; a manifold; and a caulk between the fuel cell stack and the manifold, the caulk comprising:
at least one powder component, wherein:
the powder component is a ball-milled powder component comprising ceria, zirconia, alumina, or a combination thereof,
the powder component is a heat-treated powder component that has been heated at a temperature of to least 1500° C.,
the powder component is present in a concentration range of 65 wt % to 75 wt % of the caulk composition, and
the powder component has a particle size distribution of 95% less than 25 μm and 90% greater than 1 μm; and

at least one binder component, wherein the binder component is present in a concentration range of 25 wt % to 35 wt % of the caulk composition.

9 . The MCFC of claim 8 , wherein the fuel cell stack comprises a plurality of fuel cells, with each fuel cell including a cathode, an anode, an electrically conductive separator plate, corrugated current collectors, and an electrolyte matrix.

10 . The MCFC of claim 9 , wherein the caulk is positioned on a first portion of each fuel cell formed by the electrolyte matrix and on a second portion of each fuel cell formed by the separator plate.

11 . The MCFC of claim 10 , wherein the separator plate comprises a weld bead positioned between a top trough and a bottom trough of the separator plate and wherein the weld bead remains uncovered from the caulk to form a discontinuity.

12 . The MCFC of claim 8 , wherein the caulk is positioned discontinuously over the fuel cell stack.

13 . The MCFC of claim 8 , wherein the MCFC is configured to minimize electrolyte migration from a positive end of the fuel cell stack to a negative end of the fuel cell stack.

Assignees

• Fuelcell Energy Inc

Inventors

• Snider Matthew T
• Yuh Chao-Yi

Classifications

• H01M8/244

  with matrix-supported molten electrolyte · CPC title

• H01M8/14

  Fuel cells with fused electrolytes · CPC title

• H01M8/0286

  Processes for forming seals · CPC title

• H01M8/0282 Primary

  Inorganic material · CPC title

• H01M8/2485 Primary

  Arrangements for sealing external manifolds; Arrangements for mounting external manifolds around a stack · CPC title