Additives for electrochemical cells

• US 6,395,422 B1
• Filed: 04/15/1998
• Issued: 05/28/2002
• Est. Priority Date: 06/02/1995
• Status: Expired due to Term

• Current Assignee: Energizer Brands, LLC (Energizer Holdings, Inc.)
• Original Assignee: Eveready Battery Company Incorporated (Energizer Holdings, Inc.)
• Inventors: Randell, Christopher Fred, White, Neal Charles
• Primary Examiner(s): HARDEE, JOHN R
• Application Number:
  US08/973,245
• Time in Patent Office: 1,504 Days
• Field of Search: 429/203,341,342,144
• US Class Current: 429/203
• CPC Class Codes: H01M 2300/0005 Acid electrolytes
• CPC Class Codes: H01M 2300/0014 Alkaline electrolytes
• CPC Class Codes: H01M 50/409 Separators, membranes or diaphragms characterised by the material
• CPC Class Codes: H01M 6/06 Dry cells, i.e. cells wherein the electrolyte is rendered non-fluid
• CPC Class Codes: H01M 6/16 with organic electrolyte H01M6/18 takes precedence
• CPC Class Codes: H01M 6/22 Immobilising of electrolyte
• CPC Class Codes: H01M 6/5083 Testing apparatus

Abstract

Polyoxyalkylene nitrogen containing compounds are useful in electrochemical cells having an acidic electrolyte to inhibit gassing and leakage.

Claims

1. An electrochemical cell comprising:

a zinc anode, a cathode, an acidic electrolyte, a separator between the zinc anode and the cathode, and a polyoxyalkylene nitrogen-containing compound, wherein the polyoxyalkylene portion of the polyoxyalkylene nitrogen-containing compound has a chain length of from 3 to 15 on average.

2. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound is an amine.

3. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound is an ammonium compound.

4. The electrochemical cell of claim 1, wherein the alkylene portions of the polyoxyalkylene nitrogen-containing compound are the same.

5. The electrochemical cell of claim 1, wherein the alkylene portions of the polyoxyalkylene nitrogen-containing compound are selected from ethylene and propylene groups.

6. The electrochemical cell of claim 1, wherein the alkylene portions of the polyoxyalkylene nitrogen-containing compound are ethylene groups.

7. The electrochemical cell of claim 1, wherein the nitrogen of the polyoxyalkylene nitrogen-containing compound is substituted by at least one polyoxyalkylene group, and at least one optionally substituted alkyl group.

8. The electrochemical cell of claim 7, wherein the alkyl group is substituted by one or more hydroxy groups and/or halogen atoms.

9. The electrochemical cell of claim 7, wherein the alkyl group is unsubstituted.

10. The electrochemical cell of claim 7, wherein the alkyl group is a straight chain alkyl group.

11. The electrochemical cell of claim 7, wherein the alkyl group contains from 1 to 30 carbon atoms.

12. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound contains a plurality of amine groups.

13. The electrochemical cell of claim 12, wherein the amine groups are linked to each other by alkylene groups.

14. The electrochemical cell of claim 13, wherein the alkylene groups are short chain alkylene groups.

15. The electrochemical cell of claim 14, wherein the alkylene groups are trimethylene groups.

16. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound includes two amine groups, the amine groups being linked by one alkylene group.

17. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound contains two amine groups, the amine groups being linked by one alkylene group, and wherein a first of the amine groups has one polyoxyalkylene substituent and one straight chain alkyl substituent having from 1 to 30 carbon atoms, and a second of the amine groups has two polyoxyalkylene substituents.

18. The electrochemical cell of claim 1, wherein the polyoxyalkylene portion of the polyoxyalkylene nitrogen-containing compound has a chain length of 10, on average.

19. The electrochemical cell of claim 1, wherein the polyoxyalkylene nitrogen-containing compound is derived from coconut amines.

20. An electrochemical cell comprising a zinc anode, a cathode, an acidic electrolyte, a separator between the zinc anode and the cathode, and a polyoxyalkylene nitrogen-containing compound having one of the two following general formulae:

wherein R represent an optionally substituted alkyl group having from 1 to 30 carbon atoms, R′

represents an alkyl group having a from 2 to 10 carbon atoms, each m is the same or different and represents an integer from 1 to 4 inclusive, and n, x, y, and z are the same or different, and each represents an integer from 1 to 30.

21. The electrochemical cell of claim 20, wherein R has an average of about 10 carbon atoms.

22. The electrochemical cell of claim 20, wherein R′

has 3 or 4 carbon atoms.

23. The electrochemical cell of claim 20, wherein each m is 2.

24. The electrochemical cell of claim 20, wherein n, x, y and z each averages about 10.

25. The electrochemical cell of claim 20, wherein R is unsubstituted.

26. An electrochemical cell comprising a zinc anode, a cathode, an acidic electrolyte, a separator between the zinc anode and the cathode, and a polyoxyalkylene nitrogen-containing compound having one of the two following general formulae:

wherein R represents an optionally substituted alkyl group having from 1 to 30 carbon atoms, R′

represents an alkyl group having from 2 to 10 carbon atoms and n, x, y and z are the same or different, and each represents an integer from 1 to 30.

27. The electrochemical cell of claim 26, wherein R has an average of about 10 carbon atoms.

29. The electrochemical cell of claim 26, wherein n, x, y and z each averages about 10.

30. The electrochemical cell of claim 26, wherein R is unsubstituted.

31. The electrochemical cell of claim 26, having no added mercury.

28. The electrochemical cell of 26, wherein R′

has 3 or 4 carbon atoms.