Battery circulation system with improved four-way valve

• US 6,242,125 B1
• Filed: 05/04/1999
• Issued: 06/05/2001
• Est. Priority Date: 05/06/1998
• Status: Expired due to Fees

• Current Assignee: ZB Technology Co., Ltd.
• Original Assignee: ZB Technology Co., Ltd.
• Inventors: Lex, Peter J., Jonshagen, Bjorn, Rixford, Robert R., Eidler, Phillip A.
• Primary Examiner(s): Chaney, Carol
• Assistant Examiner(s): Martin, Angela J.
• Application Number:
  US09/305,218
• Time in Patent Office: 763 Days
• Field of Search: 429/51, 429/64, 429/63, 429/61, 429/72, 429/76, 429/74, 429/71, 429/14, 429/17, 429/101, 429/105, 429/82, 429/95, 429/50
• US Class Current: 429/51
• CPC Class Codes: H01M 12/085 Zinc-halogen cells or batteries
• CPC Class Codes: H01M 50/77 with external circulating path
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A circulation system for a flowing-electrolyte battery having at least one electrochemical cell, an anolyte reservoir, and a catholyte reservoir. The circulation system includes an anolyte pump coupled in fluid flowing relationship to the anolyte reservoir which pumps anolyte from the anolyte reservoir to the at least one electrochemical cell. A catholyte pump is coupled in fluid flowing relationship to the catholyte reservoir and also pumps catholyte to the at least one electrochemical cell. A second phase pump is coupled in fluid flowing relationship to the catholyte reservoir and is used to introduce second phase electrolyte into the aqueous catholyte pumped by the catholyte pump. The second phase pump is controlled by a controller so that the second phase is introduced into the catholyte stream in a metered fashion. A controllable four-way valve is coupled in fluid flowing relationship to the catholyte pump and operable to direct the flow of catholyte through the electrochemical cell in a first direction, and periodically reverse the flow of the catholyte in a second direction. Metering the amount of second phase injected into the catholyte stream and reversing catholyte flow improve battery efficiency.

Claims

1. A circulation system for a flowing-electrolyte battery having at least one electrochemical cell, an anolyte reservoir, and a catholyte reservoir, the circulation system comprising:

an anolyte pump coupled in fluid flowing relationship to the anolyte reservoir and for pumping anolyte from the anolyte reservoir to the at least one electrochemical cell;

a catholyte pump coupled in fluid flowing relationship to the catholyte reservoir and for pumping catholyte to the at least one electrochemical cell;

a second phase pump coupled in fluid flowing relationship to the catholyte reservoir and for introducing second phase electrolyte into the aqueous catholyte pumped by the catholyte pump;

a controller for controlling the operation of the second phase pump; and

a controllable four-way valve coupled in fluid flowing relationship to the catholyte pump and operable for directing the flow of catholyte through the at least one electrochemical cell in a first direction, and periodically reversing the flow of the catholyte in a second direction.

2. A circulation system as in claim 1;

wherein the four-way valve comprises

a main body having a hollow interior portion;

a valve body housed within the hollow interior portion, the valve body having a valve stem, a first U-shaped chamber with two axially positioned legs, a second U-shaped chamber having two axially positioned legs, each leg of the first and second U-shaped members terminating in a port; and

an end cap having four ports mounted on the main body;

wherein the valve body is rotatable within the main body such that the ports of the first and second U-shaped chambers may be aligned with the ports in the end cap.

3. A circulation system as in claim 2, wherein each of the ports in the legs of the first and second U-shaped chambers includes a compressible ring topped by a substantially non-compressible, low-friction ring.

4. A circulation system as in claim 2, further comprising an actuator coupled to the valve stem of the valve body, the actuator coupled in data transmission relation to the controller.

5. A circulation system as in claim 4, wherein the controller is operable to actuate the actuator such that it rotates the four-way valve every hour for a period of one minute.

6. A circulation system as in claim 1, wherein the controller is coupled to the anolyte and catholyte pumps and operable to adjust the speeds of each.

7. A circulation system for a flowing-electrolyte battery having at least one electrochemical cell, an anolyte reservoir, and a catholyte reservoir, the circulation system comprising:

an anolyte pump mounted near the top of the anolyte reservoir and for pumping anolyte from the anolyte reservoir to the at least one electrochemical cell;

a catholyte pump mounted near the top of the catholyte reservoir and for pumping catholyte to the at least one electrochemical cell;

a second phase pump mounted near the top of the catholyte reservoir and for introducing second phase electrolyte into the aqueous catholyte pumped by the catholyte pump, the second phase pump having an intake with a mouth positioned adjacent to the bottom of the catholyte reservoir;

a controller for controlling the operation of the second phase pump; and

a controllable four-way valve coupled in fluid flowing relationship to the catholyte pump and operable for directing the flow of catholyte through the at least one electrochemical cell in a first direction, and periodically reversing the flow of the catholyte in a second direction.

8. A circulation system as in claim 7;

wherein the four-way valve comprises

a main body having a hollow interior portion;

a valve body housed within the hollow interior portion, the valve body having a valve stem, a first U-shaped chamber with two axially positioned legs, a second U-shaped chamber having two axially positioned legs, each leg of the first and second U-shaped members terminating in a port; and

an end cap having four ports mounted on the main body;

wherein the valve body is rotatable within the main body such that the ports of the first and second U-shaped chambers may be aligned with the ports in the end cap.

9. A circulation system as in claim 8, wherein each of the ports in the legs of the first and second U-shaped chambers includes a compressible ring topped by a substantially non-compressible, low-friction ring.

10. A circulation system as in claim 8, further comprising an actuator coupled to the valve stem of the valve body, the actuator coupled in data transmission relation to the controller.

11. A circulation system as in claim 10, wherein the controller is operable to actuate the actuator such that it rotates the four-way valve every hour for a period of one minute.

12. A circulation system as in claim 7, wherein the controller is coupled to the anolyte and catholyte pumps and operable to adjust the speeds of each.

13. A circulation system as in claim 7, further comprising a first level sensor positioned in the anolyte reservoir and a second level sensor positioned within the catholyte reservoir, the first and second level sensor coupled in data exchange relation to the controller, and wherein the controller adjusts the speed of the anolyte pump to adjust the level of electrolyte in the system.

14. A method of removing gas from a liquid electrolyte battery having one or more cathodic half cells, the method comprising the step of periodically reversing the direction of flow of electrolyte through the cathodic half cells to push gas out of the half cells to an electrolyte reservoir.