Electrolyte health management for redox flow battery

Patent metadata

Field	Value
Publication number	US-2021242479-A1
Application number	US-202117234509-A
Country	US
Kind code	A1
Filing date	Apr 19, 2021
Priority date	Nov 20, 2018
Publication date	Aug 5, 2021
Grant date	—

Abstract

Methods and systems are provided for a rebalancing reactor of a flow battery system. In one example, a pH of a battery electrolyte may be maintained by the rebalancing reactor by applying a negative potential to a catalyst bed of the rebalancing reactor. A performance of the rebalancing reactor may further be maintained by treating the catalyst bed with deionized water.

First claim

1 - 8 . (canceled)

9 . A redox flow battery system, comprising;
an electrolyte circulating through a cell of the redox flow battery and hydrogen gas stored in electrolyte chambers of the redox flow battery, both the electrolyte and hydrogen gas flowed to a rebalancing reactor coupled to the cell; a negative potential applied to the catalyst bed during charging of the redox flow battery; a controller, configured with computer readable instructions stored on non-transitory memory, the instructions executable by the controller to:
apply a negative potential to the catalyst bed during charging of the redox flow battery;
flush the catalyst bed with deionized water upon detection of the rate of ferric iron reduction at the rebalancing reactor falling below a second threshold; and
indicate a request for soaking of the catalyst bed in deionized water when an interval of operating time of the redox flow battery is elapsed.

10 . The redox flow battery system claim 9 , wherein the electrolyte includes ferric and ferrous iron complexes, non-redox active salts, and an acid.

11 . The redox flow battery system of claim 9 , where the hydrogen gas is generated at a negative electrode of the cell in a process that consumes protons from the electrolyte.

12 . The redox flow battery system of claim 9 , wherein the catalyst bed of the rebalancing reactor has a jelly roll structure.

13 . The redox flow battery system of claim 9 , wherein the negative potential applied to the catalyst bed is configured to generate a negative charge at the catalyst bed and wherein the negative potential is applied continuously during operation of the redox flow battery.

14 . The redox flow battery system of claim 9 , wherein the catalyst bed is flushed with deionized water while housed in the rebalancing reactor when deionized water is flowed through the rebalancing reactor.

15 . The redox flow battery system of claim 9 , wherein the catalyst is soaked when the redox flow battery system is deactivated and the catalyst is removed from the rebalancing reactor.

16 - 20 . (canceled)

Assignees

• Ess Technology Inc

Inventors

• Song Yang
• Mcdonald Timothy J
• Behr Alexandria

Classifications

• H01M2300/0005

  Acid electrolytes · CPC title

• H01M8/0444

  Concentration; Density (H01M8/04492 takes precedence) · CPC title

• H01M8/04477

  of the electrolyte · CPC title

• H01M8/0693 Primary

  Treatment of the electrolyte residue, e.g. reconcentrating · CPC title

• H01M8/04201

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title