Flow battery flow field having volume that is function of power parameter, time parameter and concentration parameter

Patent metadata

Field	Value
Publication number	US-10892499-B2
Application number	US-201314768622-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Mar 15, 2013
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A flow battery includes a cell that has first and second flow fields spaced apart from each other and an electrolyte separator layer. A supply/storage system is external of the cell and includes first and second vessels fluidly connected with the first and second flow fields, and first and second pumps configured to selectively move first and second fluid electrolytes between the vessels and the first and second flow fields. The flow fields each have an electrochemically active zone that is configured to receive flow of the fluid electrolytes. The electrochemically active zone has a total open volume that is a function of at least one of a power parameter of the flow battery, a time parameter of the pumps and a concentration parameter of the fluid electrolytes.

First claim

What is claimed is:

1. A flow battery comprising:
at least one cell having first and second flow fields spaced apart from each other, and an electrolyte separator layer arranged there between; and
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 pumps configured to selectively move first and second fluid electrolytes between the first and second vessels and the first and second flow fields,
wherein the first and second flow fields each have an electrochemically active zone configured to receive flow of the respective first and second fluid electrolytes, the electrochemically active zone having a total open volume that is a function of at least one of a power parameter of the flow battery, a time parameter of the respective first and second pumps and a concentration parameter of the respective first and second fluid electrolytes,
wherein the power parameter is a maximum rated power of the flow battery, the time parameter is the time in seconds for the first and second pumps to achieve full flow of the first and second fluid electrolyte from a low-flow state, and the concentration parameter is a concentration of at least one electrochemically active species in the first and second fluid electrolytes.

2. The flow battery as recited in claim 1 , wherein the total open volume is a function of the power parameter.

3. The flow battery as recited in claim 1 , wherein the total open volume is a function of the time parameter of the respective first and second pumps.

4. The flow battery as recited in claim 1 , wherein the total open volume is a function of the concentration parameter.

5. The flow battery as recited in claim 1 , wherein the total open volume is a function of the power parameter, the time parameter and the concentration parameter.

6. The flow battery as recited in claim 1 , wherein the total open volume is according to Equation I:
V =( S×P×t pump )/( E×F×C ),  Equation I:

wherein V is the total open volume in Liters, S is the moles of active species reacted per electron, P is a rated maximum output power of the flow battery in Watts, t pump is a time in seconds for the respective first and second pumps to achieve full flow of the fluid electrolytes from a low-flow state, E is a minimum allowable voltage in Volts, F is Faraday's constant and C is a concentration of at least one electrochemically active species in the fluid electrolytes in moles per Liter.

7. The flow battery as recited in claim 1 , wherein the total open volume is a total open volume in channels of the respective first and second flow fields and open volume in respective first and second porous electrodes adjacent the electrolyte separator layer.

8. A flow battery comprising at least one cell having a flow field adjacent an electrolyte separator layer, with a supply/storage system external of the at least one cell, the supply/storage system including a vessel fluidly connected with the flow field and a pump configured to selectively move a fluid electrolyte between the vessel and the flow field, the flow field having an electrochemically active zone configured to receive flow of the fluid electrolyte, the electrochemically active zone having a total open volume according to Equation I:
V =( S×P×t pump )/( E×F×C ),  Equation I:

wherein V is the total open volume in Liters, S is the moles of active species reacted per electron, P is a rated maximum output power of the flow battery in Watts, t pump is a time in seconds for the pump to achieve full flow of the fluid electrolyte from a low-flow state, E is a minimum allowable voltage in Volts, F is Faraday's constant and C is a concentration of at least one electrochemically active species in the fluid electrolyte in moles per Liter.

9. The flow battery as recited in claim 8 , wherein the total open volume is a total open volume in channels of the flow field and open volume in a porous electrode adjacent the electrolyte separator layer.

10. A method of managing flow battery response time to a change in power demand, the method comprising:
providing a flow battery having at least one cell including a flow field adjacent an electrolyte separator layer, with a supply/storage system external of the at least one cell, the supply/storage system including a vessel fluidly connected with the flow field and a pump configured to selectively move a fluid electrolyte between the vessel and the flow field, the pump being operable between a first, low-flow state and a second, full-flow state with respect to flow of the fluid electrolyte through the flow field; and
in response to a change in a power demand on the flow battery, ramping the pump from the first, low-flow state to the second, full-flow state over a time period and,
prior to the pump achieving the full-flow state, providing a required electrical load corresponding to the change in the power demand.

11. The method as recited in claim 10 , wherein the flow field has an electrochemically active zone configured to receive flow of the fluid electrolyte, and the providing includes establishing the electrochemically active zone to have a total open volume that is a function of at least one of a power parameter of the flow battery, a time parameter of the pump and a concentration parameter of the fluid electrolyte.

12. The method as recited in claim 11 , wherein the total open volume is a function of at least the power parameter, and power parameter is a maximum rated power of the flow battery.

13. The method as recited in claim 11 , wherein the total open volume is a function of at least the time parameter, and the time parameter is the time in seconds for the pump to achieve full flow of the fluid electrolyte from a low-flow state.

14. The method as recited in claim 1 , wherein the total open volume is a function of at least the concentration parameter, and the concentration parameter is a concentration of at least one of the electrochemically active species in the fluid electrolyte.

15. The method as recited in claim 11 , wherein the total open volume is a function of the power parameter, the time parameter and the concentration parameter.

16. The method as recited in claim 10 , wherein the total open volume is according to Equation I:
V =( S×P×t pump )/( E×F×C ),  Equation I:

wherein V is the total open volume in Liters, S is the moles of active species reacted per electron, P is a rated maximum output power of the flow battery in Watts, t pump is a time in seconds for the pump to achieve full flow of the fluid electrolyte from a low-flow state, E is a minimum allowable voltage in Volts, F is Faraday's constant and C is a concentration of an electrochemically active species in the fluid electrolyte in moles per Liter.

17. The method as recited in claim 10 , further comprising:
limiting a maximum charging rate of the flow battery to limit exposure of non-oxidized carbon surfaces to high voltage potentials.

18. The method as recited in claim 17 , including limiting the voltage ramp rate to a maximum voltage during charging of the flow battery.

19. The flow battery as recited in claim 7 , wherein the channels include a first channel and a second, adjacent channel that is separated from the first channel by a rib.

20. The flow battery as recited in claim 7 , wherein the channels positively force at least a portion of a flow of the fluid electrolyte into one of the first and se

Assignees

• United Technologies Corp
• Raytheon Tech Corp

Inventors

• Smeltz Andrew
• Darling Robert Mason
• Perry Michael L
• Ding Zhongfen

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M8/04992

  characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence · CPC title

• H01M8/04276 Primary

  Arrangements for managing the electrolyte stream, e.g. heat exchange · CPC title

• H01M8/04186

  of liquid-charged or electrolyte-charged reactants · CPC title

• H01M8/20

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