Ammonium Borophosphate as a Proton Conducting Solid Electrolyte for Solid Acid Fuel Cells

Patent metadata

Field	Value
Publication number	US-2023420717-A1
Application number	US-202318213933-A
Country	US
Kind code	A1
Filing date	Jun 26, 2023
Priority date	Jun 28, 2022
Publication date	Dec 28, 2023
Grant date	—

Abstract

A new compound (NH 4 ) 3 H 2 [BOB(PO 4 ) 3 ] was prepared and found to conduct protons under a variety of temperature conditions relevant to fuel cell operation. Also described is the related material Rb x (NH 4 ) 3-x H 2 (BOB(PO 4 ) 3 ) where 0>x≥3.

First claim

What is claimed is:

1 . The compound (NH 4 ) 3 H 2 [BOB(PO 4 ) 3 ].

2 . The compound of claim 1 , in the form of a one-dimensional polymer.

3 . A method of preparing (NH 4 ) 3 H 2 [BOB(PO 4 ) 3 ], the method comprising:
mixing (NH 4 ) 2 HPO 4 and H 3 BO 3 in an ionic liquid; and subjecting the mixture to greater than standard temperature, thereby obtaining (NH 4 ) 3 H 2 [BOB(PO 4 ) 3 ].

4 . The method of claim 3 , wherein said ionic liquid is 1-butyl-3-methylimidazolium bromide.

5 . The method of claim 3 , wherein the mixture is subjected to a temperature of between 100 and 300° C.

6 . An electrochemical device comprising:
(NH 4 ) 3 H 2 [BOB(PO 4 ) 3 ] configured as a separator membrane and/or electrode of the electrochemical device, wherein the electrochemical device is selected from the group consisting of hydrogen fuel cells, flow batteries, and electrolyzers.

7 . The electrochemical device of claim 6 , being operable at temperatures ranging from about 150 to about 300° C.

8 . The electrochemical device of claim 6 ,
wherein the electrochemical device is the flow battery; and wherein the flow battery comprises a first half cell comprising an anolyte and a second half cell comprising a catholyte.

9 . The electrochemical device of claim 6 , being operable at temperatures ranging from about 150 to about 300° C.

10 . A mixed ammonium-rubidium one-dimensional borophosphates of the formula Rb x (NH 4 ) 3-x H 2 (BOB(PO 4 ) 3 ) where 0>x≥3.

11 . A method of preparing Rb x (NH 4 ) 3-x H 2 (BOB(PO 4 ) 3 ) where 0>x≥3, the method comprising:
mixing (NH 4 ) 2 HPO 4 , Rb 2 HPO 4 , and H 3 BO 3 in an ionic liquid; and
subjecting the mixture to greater than standard temperature, thereby obtaining Rb x (NH 4 ) 3-x H 2 (BOB(PO 4 ) 3 ) where 0>x≥3.

Assignees

• Us Gov Sec Navy

Inventors

• Ridenour James August
• Chaloux Brian L
• Epshteyn Albert

Classifications

• H01M8/1016 Primary

  characterised by the electrolyte material (H01M8/12 takes precedence) · CPC title

• H01M8/188

  by recharging of redox couples containing fluids; Redox flow type batteries · CPC title

• C25B13/05

  based on inorganic materials · CPC title

• C01B35/146 Primary

  Compounds containing boron and nitrogen, e.g. borazoles (ammonium tetrafluoborates C01B35/063; ammonium borates C01B35/12) · CPC title

• H01M2300/0068

  inorganic · CPC title