Method for supplying molten carbonate fuel cell with electrolyte and molten carbonate fuel cell using the same

Patent metadata

Field	Value
Publication number	US-2018048009-A1
Application number	US-201715675233-A
Country	US
Kind code	A1
Filing date	Aug 11, 2017
Priority date	Aug 12, 2016
Publication date	Feb 15, 2018
Grant date	—

Abstract

Disclosed are a method for supplying molten carbonate fuel cell with electrolyte and a molten carbonate fuel cell using the same, wherein a molten carbonate electrolyte is generated from a molten carbonate electrolyte precursor compound in a molten carbonate fuel cell and is supplied to the molten carbonate fuel cell.

First claim

What is claimed is:

1 . A method for supplying molten carbonate fuel cell with electrolyte, comprising:
generating a molten carbonate electrolyte from a molten carbonate electrolyte precursor compound in a molten carbonate fuel cell, thereby providing the molten carbonate electrolyte to the molten carbonate fuel cell.

2 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , wherein the molten carbonate electrolyte is generated from at least one of carbonate ion, carbon dioxide and oxygen; and the molten carbonate electrolyte precursor compound.

3 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , comprising:
supplying a molten carbonate electrolyte precursor compound to a first electrode; and supplying a reaction gas containing carbon dioxide to a second electrode, wherein the carbonate ion is generated from the reaction gas and transfers to an electrochemical reaction site in the first electrode, and carbon dioxide is not supplied to the first electrode.

4 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 3 , wherein the molten carbonate electrolyte precursor compound is supplied to the first electrode in a gaseous state.

5 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 4 , wherein a mixed gas of a gaseous molten carbonate electrolyte precursor compound and a carrier gas which does not react with the first electrode is provided to the first electrode.

6 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 5 , wherein a molten carbonate electrolyte precursor compound powder is melted and provided to the first electrode in a gaseous state.

7 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 5 , wherein a molten carbonate electrolyte precursor compound powder is dissolved in a solvent, then heated, and provided to the first electrode in a gaseous state.

8 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , wherein the molten carbonate electrolyte precursor compound reacts with at least one of carbonate ion, carbon dioxide and oxygen to form a molten carbonate electrolyte, and
the molten carbonate electrolyte precursor compound is a material having a higher vapor pressure than lithium carbonate (Li 2 CO 3 ), sodium carbonate (Na 2 CO 3 ), or potassium carbonate (K 2 CO 3 ) at an operating temperature of the molten carbonate fuel cell.

9 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , wherein the molten carbonate electrolyte precursor compound is a compound comprising at least one selected from the group consisting of lithium (Li), sodium (Na) and potassium (K); or
a compound comprising at least one selected from the group consisting of lithium (Li), sodium (Na) and potassium (K) and additionally comprising at least one selected from the group consisting of cesium (Cs), lanthanum (La), and rubidium.

10 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , wherein the molten carbonate electrolyte precursor compound is at least one selected from the group consisting of metal lithium (Li), Li 2 O, LiOH and a hydrate of LiOH, LiF, LiCl, LiI, Li 3 N, LiNH 2 , Li 2 C 2 , LiMoO 4 , LiAlH 4 , LiSn, LiPb, LiTi, LiHg, Li 3 Sb 2 , Li 3 Bi, Li 2 SO 4 , LiOCH 3 , LiOC 2 H 5 , metal sodium (Na), Na 2 O, NaOH and a hydrate of NaOH, NaF, NaCl, NaI, Na 3 N, NaNH 2 , Na 2 SO 4 , Na 2 C 2 O 4 , NaC 2 H 3 O 2 , NaOCH 3 , NaOC 2 H 5 , metal potassium (K), K 2 O, KOH and a hydrate of KOH, KF, KCl, KI, K 3 N, KNH 2 , and K 2 SO 4 .

11 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , wherein the molten carbonate electrolyte precursor compound comprises LiI and KI.

12 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 9 , wherein the molten carbonate electrolyte is Li—K-based molten carbonate electrolyte, Li—Na-based molten carbonate electrolyte, or Li—Na—K-based molten carbonate electrolyte; or
the molten carbonate electrolyte is Li—K-based molten carbonate electrolyte, Li—Na-based molten carbonate electrolyte, or Li—Na—K-based molten carbonate electrolyte which additionally comprises at least one selected from the group consisting of Cs 2 CO 3 , Rb 2 CO 3 , and La 2 CO 3 .

13 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 3 , wherein the molten carbonate fuel cell is operated in a water electrolysis mode in which a current is applied,
a first electrode is an air electrode and a second electrode is a fuel electrode, a reaction gas containing hydrogen, carbon dioxide and water vapor or a reaction gas containing carbon dioxide and oxygen or oxygen-containing gas in an oxygen partial pressure range in which the fuel electrode is not oxidized is supplied to the fuel electrode, and carbonate ion generated in the fuel electrode by applying a current transfers to an air electrode and a molten carbonate electrolyte is generated at an electrochemical reaction site in the air electrode.

14 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 3 , wherein the molten carbonate fuel cell is operated in a fuel cell mode in which a current is output,
a first electrode is a fuel electrode and a second electrode is an air electrode, a reaction gas containing oxygen or oxygen-containing gas and carbon dioxide is supplied to the air electrode, and carbonate ion generated in the air electrode by generating a current transfers to the fuel electrode and a molten carbonate electrolyte is generated at an electrochemical reaction site in the fuel electrode.

15 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 3 , wherein the molten carbonate electrolyte is generated by a reaction of at least one of oxygen and carbon dioxide generated from carbonate ion with the molten carbonate electrolyte precursor compound.

16 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 15 , wherein oxygen generated from carbonate ion reacts with the molten carbonate electrolyte precursor compound to produce a molten carbonate electrolyte intermediate precursor compound, and the molten carbonate electrolyte intermediate precursor compound reacts with the carbon dioxide generated from carbonate ion to generate the molten carbonate electrolyte.

17 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 1 , the method comprising:
supplying a molten carbonate electrolyte precursor compound to a first electrode; and supplying a reaction gas containing carbon dioxide to a second electrode, wherein the reaction gas transfers to an electrochemical reaction site in the first electrode by either of a concentration difference of the reaction gas between the first and second electrodes or a pressure difference between the first and second electrodes, and carbon dioxide is not supplied to a first electrode.

18 . The method for supplying molten carbonate fuel cell with electrolyte according to claim 17 , wherein the reaction gas comprises carbon dioxide, water vapor and hydrogen; or the reaction gas comprises carbon dioxide and oxygen or oxygen-containing gas.

19 . The method for supplying molten carbonate fuel cell with electrolyte according

Assignees

• Korea Inst Sci & Tech

Inventors

• Yoon Sung Pil
• Han Jonghee
• Ham Hyung Chul
• Yoon Chang Won
• Choi Sun Hee
• Park Hyun Seo
• Kim Yeong Cheon
• Lee Chang Whan
• Kim Hyoung Juhn
• Lim Tae Hoon
• Nam Suk Woo
• Jang Seong Cheol

Classifications

• C01D3/12

  Iodides · CPC title

• H01M8/145 Primary

  comprising carbonates · CPC title

• C01D7/00

  Carbonates of sodium, potassium or alkali metals in general · CPC title

• H01M8/04283

  Supply means of electrolyte to or in matrix-fuel cells · CPC title

• C25B1/14

  Alkali metal compounds · CPC title