Flow battery with hydrated ion-exchange membrane having maximum water domain cluster sizes

Patent metadata

Field	Value
Publication number	US-2016126579-A1
Application number	US-201314891013-A
Country	US
Kind code	A1
Filing date	May 16, 2013
Priority date	May 16, 2013
Publication date	May 5, 2016
Grant date	—

Abstract

A flow battery includes a cell that has a first electrode, a second electrode spaced apart from the first electrode and an electrolyte separator layer arranged between the first electrode and the second electrode. A supply/storage system is external of the at least one cell and includes first and second vessels that are fluidly connected with the at least one cell. First and second fluid electrolytes are located in the supply/storage system. The electrolyte separator layer includes a hydrated ion-exchange membrane of a polymer that has a carbon backbone chain and side chains extending from the carbon backbone chain. The side chains include hydrophilic chemical groups with water molecules attached by secondary bonding to form clusters of water domains. The clusters have an average maximum cluster size no greater than 4 nanometers, with an average number of water molecules per hydrophilic chemical group, λ (lambda), being greater than zero.

First claim

What is claimed is:

1 . A flow battery comprising:
at least one cell including a first electrode, a second electrode spaced apart from the first electrode and an electrolyte separator layer arranged between the first electrode and the second electrode; a supply/storage system external of the at least one cell, the supply/storage system including first and second vessels fluidly connected with the at least one cell; and first and second fluid electrolytes in the supply/storage system, wherein the electrolyte separator layer includes a hydrated ion-exchange membrane of a polymer comprising a carbon backbone chain and side chains extending from the carbon backbone chain, the side chains including hydrophilic chemical groups with water molecules attached by secondary bonding thereto to form clusters of water domains, the clusters having average maximum cluster sizes no greater than 4 nanometers, with an average number of water molecules per hydrophilic chemical group, λ (lambda), being greater than zero, the average maximum cluster size of no greater than 4 nanometers and the λ (lambda) limiting migration of vanadium or iron ions across the hydrated ion-exchange membrane.

2 . The flow battery as recited in claim 1 , wherein the carbon backbone chain is perfluorinated.

3 . The flow battery as recited in claim 1 , wherein the hydrophilic chemical groups are sulfonic acid groups, —SO 3 H.

4 . The flow battery as recited in claim 1 , wherein the polymer includes perfluorosulfonic acid.

5 . The flow battery as recited in claim 1 , wherein the hydrophilic chemical groups are carboxylic acid groups, —COOH.

6 . The flow battery as recited in claim 1 , wherein the hydrophilic chemical groups are terminal end groups of the side chains.

7 . The flow battery as recited in claim 1 , wherein λ (lambda) is less than or equal to 22.

8 . The flow battery as recited in claim 1 , wherein the hydrated ion-exchange membrane has a specific conductivity of 0.01 to 0.2 S/cm.

9 . The flow battery as recited in claim 1 , wherein the hydrated ion-exchange membrane has an average thickness of 25-178 micrometers.

10 . The flow battery as recited in claim 1 , wherein the first and second fluid electrolytes include an electrochemically active specie of vanadium.

11 . The flow battery as recited in claim 1 , wherein the hydrated ion-exchange membrane includes at least one of cations and anions bonded to the hydrophilic groups.

12 . The flow battery as recited in claim 11 , wherein the hydrated ion-exchange membrane includes cations, the cations are selected from the groups consisting of lithium, sodium, potassium, rubidium, cesium and combinations thereof.

13 . The flow battery as recited in claim 11 , wherein the hydrated ion-exchange membrane includes cations, the cations are selected from the groups consisting of potassium, rubidium, cesium and combinations thereof.

14 . The flow battery as recited in claim 11 , wherein the hydrated ion-exchange membrane includes anions, the anions including chlorine.

15 . The flow battery as recited in claim 1 , wherein the hydrated ion-exchange membrane has a percent crystallinity of at least 6%.

16 . The flow battery as recited in claim 1 , wherein a maximum design operating temperature of the hydrated ion-exchange membrane is below the glass transition temperature of the polymer.

17 . The flow battery as recited in claim 1 , wherein the side chains each include 5 or fewer carbon atoms.

18 . The flow battery as recited in claim 1 , wherein the polymer has an equivalent weight of 800 g/eq or greater.

19 . The flow battery as recited in claim 1 , wherein the polymer is cross-linked.

20 . The flow battery as recited in claim 1 , wherein the hydrophilic chemical groups include, respectively, an anion group bonded with a positive chemical group.

21 . The flow battery as recited in claim 20 , wherein the positive chemical group is an amine group.

22 . A flow battery comprising:
at least one cell including a first electrode, a second electrode spaced apart from the first electrode and an electrolyte separator layer arranged between the first electrode and the second electrode; a supply/storage system external of the at least one cell, the supply/storage system including first and second vessels fluidly connected with the respective first and second flow fields; and first and second fluid electrolytes in the supply/storage system, wherein the electrolyte separator layer includes a hydrated perfluorosulfonic acid ion-exchange membrane comprising a perfluorinated carbon backbone chain and perfluorinated carbon side chains extending from the perfluorinated carbon backbone chain, the perfluorinated carbon side chains terminating in hydrophilic chemical groups with water molecules attached by secondary bonding thereto to form clusters of water domains, the clusters having average maximum cluster sizes no greater than 4 nanometers, with an average number of water molecules per hydrophilic chemical group, λ (lambda), being greater than zero and less than or equal to 22.

Assignees

• United Technologies Corp

Inventors

• Darling Robert Mason
• Perry Michael L
• Xie Wei

Classifications

• H01M8/20

  Indirect fuel cells, e.g. fuel cells with redox couple being irreversible (H01M8/18 takes precedence) · CPC title

• H01M8/1023 Primary

  having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes · CPC title

• H01M8/1039

  halogenated, e.g. sulfonated polyvinylidene fluorides · CPC title

• H01M8/1067 Primary

  characterised by their physical properties, e.g. porosity, ionic conductivity or thickness · CPC title

• H01M8/188 Primary

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