Method and apparatus for maintaining the pH in zinc-bromine battery systems

• US 4,540,639 A
• Filed: 06/19/1984
• Issued: 09/10/1985
• Est. Priority Date: 12/01/1982
• Status: Expired due to Term

• Current Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Original Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Inventors: Grimes, Patrick G.
• Primary Examiner(s): LeFevour, Charles F.
• Application Number:
  US06/622,183
• Time in Patent Office: 448 Days
• Field of Search: 429/14, 429/15, 429/17, 429/19, 429/13, 429/50, 429/51, 429/101, 429/105, 423/487
• US Class Current: 429/402
• CPC Class Codes: H01M 10/365 Zinc-halogen accumulators
• CPC Class Codes: H01M 10/52 Removing gases inside the secondary cell, e.g. by absorption vent plugs or other mechanical arrangements for facilitating escape of gases H01M50/30
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A method and apparatus for maintaining the pH level in a zinc-bromine battery features reacting decomposition hydrogen with bromine in the presence of a catalyst. The catalyst encourages the formation of hydrogen and bromine ions. The decomposition hydrogen is therefore consumed, alloying the pH of the system to remain substantially at a given value.

Claims

1. A method for recombining gaseous decomposition hydrogen with bromine in a zinc-bromine battery system, comprising the steps of:

reacting gaseous decomposition hydrogen with bromine within said zinc-bromine system in the presence of a catalyst supported on an electronically conductive substrate and disposed at a gas/liquid interface of said system for causing formation of hydrogen and bromide ions, whereby said gaseous decomposition hydrogen is consumed and the pH of the system is substantially maintained at a given value.

2. The method of claim 1, wherein said catalyst comprises ruthenium.

3. The method of claim 1, wherein said catalyst is disposed in a reservoir of said system.

4. The method of claim 1, wherein said catalyst is free-floating in a liquid phase of said system.

5. A zinc-bromine battery system which consumes its decomposition gaseous hydrogen so that the pH of the system is substantially maintained at a given value, comprising a catalyst supported on an electronically conductive substrate and disposed at a gas/liquid interface of said system for causing formation of hydrogen and bromide ions in the presence of said decomposition gaseous hydrogen and bromine.

6. The zinc-bromine battery system of claim 5, wherein said catalyst comprises ruthenium.

7. The zinc-bromine battery system of claim 5, wherein said catalyst is disposed in a reservoir of said system.

8. The zinc-bromine battery system of claim 5, wherein said catalyst is free-floating in a liquid phase of said system.