Long life lithium batteries with stabilized electrodes

• US 20050019670A1
• Filed: 05/28/2004
• Published: 01/27/2005
• Est. Priority Date: 07/17/2003
• Status: Active Grant

• Current Assignee: U Chicago Argonne, LLC
• Original Assignee: U Chicago Argonne, LLC
• Inventors: Kim, Jaekook, Amine, Khalil, Vissers, Donald R.
• Granted Patent: US 7,968,235 B2
• Time in Patent Office: Days
• US Class Current: 429/326
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 6/166 by the solute
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention relates to non-aqueous electrolytes having stabilization additives and electrochemical devices containing the same. Thus the present invention provides electrolytes containing an alkali metal salt, a polar aprotic solvent, a first additive that is a substituted or unsubstituted organoamine, substituted or unsubstituted alkane, substituted or unsubstituted alkene, or substituted or unsubstituted aryl compound, and/or a second additive that is a metal(chelato)borate. When used in electrochemical devices with, e.g., lithium manganese oxide spinel electrodes, the new electrolytes provide batteries with improved calendar and cycle life.

Claims

1. A non-aqueous electrolyte comprising:

an alkali metal salt;

a polar aprotic solvent;

a first additive that is a substituted or unsubstituted organoamine, a substituted or unsubstituted alkane, a substituted or unsubstituted alkene, a substituted or unsubstituted aryl compound, or a mixture of any two or more thereof; and

a second additive that is a metal(chelato)borate.

2. The non-aqueous electrolyte of claim 1 wherein the first additive is pyridazine, vinyl pyridazine, quinoline, vinyl quinoline, pyridine, vinyl pyridine, indole, vinyl indole, triethanolamine, 1,3-dimethyl butadiene, butadiene, vinyl ethylene carbonate, vinyl carbonate, imidazole, vinyl imidazole, piperidine, vinyl piperidine, pyrimidine, vinyl pyrimidine, pyrazine, vinyl pyrazine, isoquinoline, vinyl isoquinoline, quinoxaline, vinyl quinoxaline, biphenyl, 1,2-diphenyl ether, 1,2-diphenylethane, o-terphenyl, N-methyl pyrrole, naphthalene, or a mixture of any two or more thereof.

3. The non-aqueous electrolyte of claim 1 wherein the first additive is N-methyl pyrrole, 2-vinyl pyridine, 4-vinyl pyridine, triethanolamine, or biphenyl.

4. The non-aqueous electrolyte of claim 1 wherein the second additive is a lithium(chelato)borate.

5. The non-aqueous electrolyte of claim 1 wherein the second additive is Li[(C₂O₄)₂B] or Li(C₂O₄)BF₂.

6. The non-aqueous electrolyte of claim 5 wherein the first additive is N-methyl pyrrole, 2-vinyl pyridine, 4-vinyl pyridine, triethanolamine or biphenyl.

7. The non-aqueous electrolyte of claim 1 wherein the alkali metal salt is a lithium salt.

8. The non-aqueous electrolyte of claim 1 wherein the alkali metal salt is LiClO₄, LiBF₄, LiAsF₆, LiPF₆, LiCF₃SO₃, Li(CF₃SO₂)₂N, Li(CF₃SO₂)₃C, LiN(SO₂C₂F₅)₂, lithium alkyl fluorophosphates, or a mixture of any two or more thereof.

9. The non-aqueous electrolyte of claim 1 wherein the polar aprotic solvent is ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl ether, gamma butyrolactone, or a mixture of any two or more thereof.

24. An electrochemical device comprising:

a cathode;

an anode; and

an electrolyte of claim 1.

25. The electrochemical device of claim 24 wherein the device is a lithium secondary battery;

the cathode is a lithium metal oxide cathode;

the anode is a carbon or lithium metal anode; and

the anode and cathode are separated from each other by a porous separator

26. The electrochemical device of claim 25 wherein the cathode comprises LiCoO₂, LiNiO₂, LiNi₁₋

xCo_yMet_zO₂, LiMn_0.5Ni_0.5O₂, LiMn_0.3Co_0.3Ni_0.3O₂, LiFePO₄, LiMn₂O₄, LiFeO₂, LiMet_0.5Mn_1.5O₄, vanadium oxide, or mixtures of any two or more thereof, wherein Met is Al, Mg, Ti, B, Ga, Si, Ni, or Co, and wherein 0<

x<

0.3, 0<

y<

0.5, and 0<

z<

0.5.

27. The electrochemical device of claim 25 wherein the cathode comprises a spinel manganese oxide with a formula of Li_1+xMn₂₋

zMet_yO<sub>4−

m</sub>X_n, wherein Met is Al, Mg, Ti, B, Ga, Si, Ni, or Co, and X is S or F, and wherein 0<

x<

0.3, 0<

y<

0.5, 0<

z<

0.5, 0<

m<

0.5 and 0<

n<

0.5.

28. The electrochemical device of claim 25 wherein the anode comprises graphite, carbon, Li₄Ti₅O₁₂, tin alloys, silica alloys, intermetallic compounds, lithium metal, or mixtures of any two or more thereof.

29. The electrochemical device according to claim 25 wherein the first additive and the second additive are independently present in an amount from about 0.0005 to about 30 wt %.

30. The electrochemical device according to claim 25 wherein the first additive is present in an amount from about 0.001 to about 10 wt %.

31. The electrochemical device of claim 25 wherein the first additive is present in an amount of about 0.01 to 2 wt %.

32. The electrochemical device of claim 25 wherein the second additive is present in an amount of about 0.001 to about 2 wt %.

35. A method of making the non-aqueous electrolyte of claim 1, the method comprising combining

an alkali metal salt;

a polar aprotic solvent;

a first additive that is a substituted or unsubstituted organoamine, a substituted or unsubstituted alkene, or a substituted or unsubstituted aryl compound; and

a second additive that is a metal(chelato)borate.

10. A non-aqueous electrolyte comprising:

an alkali metal salt;

a polar aprotic solvent; and

a first additive that is a substituted or unsubstituted unsaturated organoamine.

11. The non-aqueous electrolyte of claim 10 wherein the first additive is vinyl pyridazine, vinyl quinoline, vinyl pyridine, vinyl indole, vinyl imidazole, vinyl piperidine, vinyl pyrimidine, vinyl pyrazine, vinyl isoquinoline, vinyl quinoxaline, or a mixture of any two or more thereof.

12. The non-aqueous electrolyte of claim 10 wherein the first additive is vinyl pyridine.

13. The non-aqueous electrolyte of claim 12 wherein the first additive is 2- or 4-vinyl pyridine.

14. The non-aqueous electrolyte of claim 10 further comprising a second additive that is Li[(C₂O₄)₂B] or Li(C₂O₄)BF₂.

15. The non-aqueous electrolyte of claim 10 wherein the alkali metal salt is a lithium salt.

16. The non-aqueous electrolyte of claim 10 wherein the alkali metal salt is LiClO₄, LiBF₄, LiAsF₆, LiPF₆, LiCF₃SO₃, Li(CF₃SO₂)₂N, Li(CF₃SO₂)₃C, LiN(SO₂C₂F₅)₂, lithium alkyl fluorophosphates, or a mixture of any two or more thereof.

33. An electrochemical device comprising:

a cathode;

an anode; and

an electrolyte of claim 10.

36. A method of making the non-aqueous electrolyte of claim 10, the method comprising combining

an alkali metal salt;

a polar aprotic solvent; and

a first additive that is a substituted or unsubstituted unsaturated organoamine.

17. A non-aqueous electrolyte comprising:

an alkali metal salt other than Li[(C₂O₄)₂B];

a polar aprotic solvent; and

an additive that is a metal(chelato)borate.

18. The non-aqueous electrolyte of claim 17 wherein the additive is a lithium (chelato)borate.

19. The non-aqueous electrolyte of claim 17 wherein the additive is Li[(C₂O₄)₂B] or Li(C₂O₄)BF₂.

20. The non-aqueous electrolyte of claim 17, wherein the additive is present in an amount of about 0.0005 to about 10 wt %.

21. The non-aqueous electrolyte of claim 17, wherein the additive is present in an amount of about 0.0005 to about 2 wt %.

22. The non-aqueous electrolyte of claim 17 wherein the alkali metal salt is a lithium salt.

23. The non-aqueous electrolyte of claim 17 wherein the alkali metal salt is LiClO₄, LiBF₄, LiAsF₆, LiPF₆, LiCF₃SO₃, Li(CF₃SO₂)₂N, Li(CF₃SO₂)₃C, LiN(SO₂C₂F₅)₂, lithium alkyl fluorophosphates, or a mixture of any two or more thereof.

34. An electrochemical device comprising:

a cathode;

an anode; and

an electrolyte of claim 18.

37. A method of making the non-aqueous electrolyte of claim 17, the method comprising combining

an alkali metal salt other than Li[(C₂O₄)₂B];

a polar aprotic solvent; and

an additive that is a metal(chelato)borate.