Lithium-ion electrochemical cells including fluorocarbon electrolyte additives

• US 9,455,472 B2
• Filed: 05/30/2012
• Issued: 09/27/2016
• Est. Priority Date: 06/07/2011
• Status: Active Grant

• Current Assignee: Gelion Technologies Pty Ltd
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Lamanna, William M., Xiao, Ang, Triemert, Matthew J., Pham, Phat T.
• Primary Examiner(s): Gatewood, Daniel
• Application Number:
  US14/122,596
• Publication Number:
  US 20140093783A1
• Time in Patent Office: 1,581 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0564 the electrolyte being constituted of organic materials only
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 10/0567 characterised by the additives
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 2300/0065 Solid electrolytes
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• 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 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Lithium-ion electrochemical cells are provided that include a positive electrode that includes a lithium metal oxide or a lithium metal phosphate, a negative electrode capable of intercalating or alloying with lithium, and an electrolyte that includes an additive. The additive includes a multifunctional anion that has the formula, X—SO₂—R_f—SO₂—Y, wherein X and Y are, independently, either O— or R_fSO₂N—, R_f is a straight or branched fluoroalkyl moiety having from 1 to 6 carbon atoms, and can, optionally, contain one or more in-chain heteroatoms, wherein R_f is a straight or branched chain or cyclic fluoroalkylene having from 1 to 10 carbon atoms and can, optionally, contain one or more in-chain heteroatoms, and wherein both R_f and R_f have a maximum of 20% non-fluorine substituents. The provided additives can improve the performance, hydrolytic stability, and thermal stability of the provided electrochemical cells.

Claims

1. A lithium-ion electrochemical cell comprising:

a positive electrode comprising a lithium metal oxide or a lithium metal phosphate;

a negative electrode capable of intercalating lithium or alloying with lithium; and

a liquid or gel electrolyte comprising a lithium electrolyte salt and an additive, wherein the additive includes a multifunctional anion that has the formula;

⁻

OSO₂(CF₂)_nSO₂O⁻

,

where n=1-10, and

wherein the additive is present the electrolyte in an amount of from 0.01 to 3 weight percent, based on the total weight of the electrolyte.

2. A lithium-ion electrochemical cell according to claim 1, wherein the positive electrode comprises a lithium metal oxide.

3. A lithium-ion electrochemical cell according to claim 2, wherein the lithium metal oxide comprises a lithium mixed metal oxide that includes cobalt, nickel, manganese, or a combination thereof.

4. A lithium-ion electrochemical cell according to claim 1, wherein the n=1-4.

5. A lithium-ion electrochemical cell according to claim 1, wherein the additive is present in an amount of from about 0.1 weight percent to about 1.0 weight percent of the total weight of the electrolyte.

6. A lithium-ion electrochemical cell according to claim 1, wherein the additive includes at least one lithium ion.

7. A lithium-ion electrochemical cell according to claim 1, further comprising a charge-carrying medium and an electrolyte salt.

8. A lithium-ion electrochemical cell according to claim 7, wherein the charge-carrying medium comprises an organic carbonate.

9. A lithium-ion electrochemical cell according to claim 8, wherein the organic carbonate comprises ethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, vinylene carbonate, 2-fluoroethylene carbonate, or a combination thereof.

10. A lithium-ion electrochemical cell according to claim 9, wherein the organic carbonate comprises vinylene carbonate.

11. A lithium-ion electrochemical cell according to claim 7, wherein the electrolyte salt is selected from LiPF₆, LiBF₄, LiClO₄, lithium bis(oxalato)borate, LiN(SO₂CF₃)₂, LiN(SO₂C₂F₅)₂, LiAsF₆, LiC(SO₂CF₃)₃, LiN(SO₂F)₂, LiN(SO₂F)(SO₂CF₃), LiN(SO₂F)(SO₂C₄F₉), and combinations thereof.

12. A lithium-ion electrochemical cell according to claim 11, wherein the electrolyte salt comprises LiPF₆, or lithium bis(oxalate)borate.

13. A lithium-ion electrochemical cell according to claim 12, wherein the electrolyte further comprises vinylene carbonate.

14. A lithium-ion electrochemical cell according to claim 1, wherein the additive is perfluorinated.

15. A method of stabilizing a lithium-ion electrochemical cell comprising:

providing a lithium-ion electrochemical cell having a lithium metal oxide positive electrode or a lithium metal phosphate positive electrode, a negative electrode capable of intercalating or alloying with lithium, and a liquid electrolyte comprising a lithium electrolyte salt,

adding a multifunctional anion that has the formula;

⁻

OSO₂(CF₂)_nSO₂O⁻

,

where n=1-10, and

wherein the multifunctional anion is present the electrolyte in an amount of from 0.01 to 3 weight percent, based on the total weight of the electrolyte.