Redox flow battery

Patent metadata

Field	Value
Publication number	US-9966626-B2
Application number	US-201515119908-A
Country	US
Kind code	B2
Filing date	Feb 16, 2015
Priority date	Feb 20, 2014
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

The present invention relates to a redox flow battery, and more particularly, to a redox flow battery which is charged and discharged by supplying a positive electrolyte and a negative electrolyte to a battery cell using an active material containing vanadium and a cation exchange membrane, in which the positive electrolyte and the negative electrolyte contain vanadium ions as active ions, the difference in volume between the positive electrolyte and the negative electrolyte is maintained at 10% or less, and the total concentration of anions in the negative electrolyte is higher than the total concentration of anions in the positive electrolyte, whereby the transfer of water in the battery is controlled and a change in the volume of the electrolytes is minimized.

First claim

The invention claimed is:

1. A redox flow battery which is charged and discharged by supplying a positive electrolyte and a negative electrolyte to a battery cell,
wherein the battery cell includes a cation exchange membrane, and the positive electrolyte and the negative electrolyte include an active material containing vanadium ions, and
wherein while charging and discharging the redox flow battery, a difference in volume between the positive electrolyte and the negative electrolyte is maintained at 10% or less, and
a total anion concentration of the negative electrolyte is higher than a total anion concentration of the positive electrolyte.

2. The redox flow battery of claim 1 , wherein anions in each of the positive electrolyte and the negative electrolyte includes: anion (A) dissociated from the active material; and anion (B) dissociated from a supporting electrolyte, in which the anion (A) and the anion (B) are the same or different.

3. The redox flow battery of claim 2 , wherein the amount of the active material in the positive electrolyte is the same as the amount of the active material in the negative electrolyte, and the amount of the supporting electrolyte in the negative electrolyte is larger than the amount of the supporting electrolyte in the positive electrolyte.

4. The redox flow battery of claim 1 , wherein the concentration of the vanadium ions in the positive electrolyte is the same as the concentration of the vanadium ions in the negative electrolyte.

5. The redox flow battery of claim 1 , wherein a ratio of a total anion concentration (C 1 ) of the negative electrolyte to a total anion concentration (C 2 ) of the positive electrolyte satisfies the following condition 1:
1< C 1 /C 2 ≤2.  Condition 1

6. The redox flow battery of claim 1 , wherein a ratio of a total anion concentration (C 1 ) of the negative electrolyte to a vanadium ion concentration (C 3 ) of the negative electrolyte satisfies the following condition 2:
2≤ C 1 /C 3 ≤3.5.  Condition 2

7. The redox flow battery of claim 1 , wherein a ratio of a total anion concentration (C 2 ) of the positive electrolyte to a vanadium ion concentration (C 4 ) of the positive electrolyte satisfies the following condition 3:
2≤ C 2 /C 4 ≤3.5.  Condition 3

8. The redox flow battery of claim 1 , wherein the positive electrolyte or the negative electrolyte further includes a cation selected from the group consisting of alkali metal ions, alkaline earth metal ions and zinc group metal ions.

Assignees

• Oci Co Ltd

Inventors

• Hong Ji-Eun
• Lee Seung-Yoen
• Kim Soo-Whan
• Ye Hee-Chang
• Kim Byung-Chul

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M8/02

  Details (electrodes H01M4/86 - H01M4/98) · CPC title

• H01M8/188 Primary

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

• Y02E60/528

  Cross-Sectional Technologies · mapped topic

• H01M8/20

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