Fluorinated electrolyte compositions

• US 10,044,066 B2
• Filed: 03/08/2013
• Issued: 08/07/2018
• Est. Priority Date: 06/01/2012
• Status: Active Grant

• Current Assignee: Syensqo SA
• Original Assignee: Solvary SA
• Inventors: Dubois, Charles J., Kodokian, George K., Nyland, Barbara S
• Primary Examiner(s): WEINER, LAURA S
• Application Number:
  US14/404,214
• Publication Number:
  US 20150171467A1
• Time in Patent Office: 1,978 Days
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 10/0567 characterised by the additives
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0028 characterised by the solvent
• CPC Class Codes: H01M 2300/0034 Fluorinated solvents
• CPC Class Codes: H01M 2300/0037 Mixture of solvents
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• 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 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 6/164 by the solvent
• CPC Class Codes: H01M 6/166 by the solute
• CPC Class Codes: H01M 6/168 by additives
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Electrolyte compositions comprising novel fluorine-containing carboxylic acid ester solvents are described. The fluorine-containing carboxylic acid ester solvents are represented by the formula R¹—C(O)O—R², wherein

• • R¹ is CH₃CH₂— and R² is —CH₂CHF₂,
  • R¹ is CH₃— and R² is —CH₂CH₂CHF₂,
  • R¹ is CH₃CH₂— and R² is —CH₂CH₂CHF₂,
  • R¹ is CHF₂CH₂CH₂— and R² is —CH₂CH₃, or
  • R¹ is CHF₂CH₂— and R² is —CH₂CH₃.
    The electrolyte compositions are useful in electrochemical cells, such as lithium ion batteries.

Claims

1. An electrolyte composition comprising (a) at least one electrolyte salt, and (b) at least one fluorine-containing carboxylic acid ester represented by the formula R¹—

C(O)O—

R²,

wherein

R¹ is CH₃CH₂— and

R² is —

CH₂CHF₂,

R¹ is CH₃— and

R² is —

CH₂CH₂CHF₂,

R¹ is CH₃CH₂— and

R² is —

CH₂CH₂CHF₂,

R¹ is CHF₂CH₂CH₂— and

R² is —

CH₂CH₃, or

R¹ is CHF₂CH₂— and

R² is —

CH₂CH₃;

wherein the fluorine-containing carboxylic acid ester is prepared with a purity level of at least about 99.9%.

2. The electrolyte composition of claim 1, wherein the fluorine-containing carboxylic acid ester is CH₃CH₂—

COO—

CH₂CF₂H or CH₃—

COO—

CH₂CH₂CF₂H.

3. The electrolyte composition of claim 1 further comprising at least one carbonate co-solvent.

4. The electrolyte composition of claim 3 wherein the carbonate co-solvent is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, vinylethylene carbonate, fluoroethylene carbonate, 2,2,2-trifluoroethyl carbonate, and methyl 2,2,3,3-tetrafluoropropyl carbonate.

5. The electrolyte composition of claim 1 wherein the electrolyte salt is selected from one or more members of the group consisting of:

lithium hexafluorophosphate,

Li PF₃(CF₂CF₃)₃,

lithium bis(trifluoromethanesulfonyl)imide,

lithium bis (perfluoroethanesulfonyl)imide,

lithium (fluorosulfonyl) (nonafluorobutanesulfonyl)imide,

lithium bis(fluorosulfonyl)imide,

lithium tetrafluoroborate,

lithium perchlorate,

lithium hexafluoroarsenate,

lithium trifluoromethanesulfonate,

lithium tris (trifluoromethanesulfonyl)methide,

lithium bis(oxalato)borate,

lithium difluoro(oxalato)borate,

Li₂B₁₂F_12-xH_xwhere x is equal to 0 to 8, and

a mixture of lithium fluoride and an anion receptor.

6. The electrolyte composition of claim 1 further comprising at least one film-forming additive.

7. An electrochemical cell comprising:

(a) a housing;

(b) an anode and a cathode disposed in said housing and in ionically conductive contact with one another;

(c) an electrolyte composition disposed in said housing and providing an ionically conductive pathway between said anode and said cathode, wherein the electrolyte composition comprises;

(i) at least one electrolyte salt; and

(ii) at least one fluorine-containing carboxylic acid ester represented by the formula R¹—

C(O)O—

R², wherein

R¹ is CH₃CH₂— and

R² is —

CH₂CHF₂,

R¹ is CH₃— and

R² is —

CH₂CH₂CH F₂,

R¹ is CH₃CH₂— and

R² is —

CH₂CH₂CHF₂,

R¹ is CHF₂CH₂CH₂— and

R² is —

CH₂CH₃, or

R¹ is CHF₂CH₂— and

R² is —

CH₂CH₃; and

(d) a porous separator between said anode and said cathode;

wherein the fluorine-containing carboxylic acid ester is prepared with a purity level of at least about 99.9%.

8. The electrochemical cell of claim 7, wherein the electrolyte composition further comprises at least one carbonate co-solvent.

9. The electrochemical cell of claim 8 wherein the carbonate co-solvent is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, vinylethylene carbonate, fluoroethylene carbonate, 2,2,2-trifluoroethyl carbonate, and methyl 2,2,3,3-tetrafluoropropyl carbonate.

10. The electrochemical cell of claim 7, wherein said electrochemical cell is a lithium ion battery.

11. The lithium ion battery of claim 10, wherein the anode is lithium titanate or graphite.

12. An electronic device comprising an electrochemical cell according to claim 7.

13. A lithium ion battery, comprising:

(a) a housing;

(b) an anode and a cathode disposed in said housing and in ionically conductive contact with one another;

(c) an electrolyte composition disposed in said housing and providing an ionically conductive pathway between said anode and said cathode, wherein the electrolyte composition comprises;

(i) at least one electrolyte salt; and

(ii) at least one fluorine-containing carboxylic acid ester represented by the formula R¹—

C(O)O—

R², wherein

R¹ is CH₃CH₂— and

R² is —

CH₂CHF₂,

R¹ is CH₃— and

R² is —

CH₂CH₂CH F₂,

R¹ is CH₃CH₂— and

R² is —

CH₂CH₂CHF₂,

R¹ is CHF₂CH₂CH₂— and

R² is —

CH₂CH₃, or

R¹ is CHF₂CH₂— and

R² is —

CH₂CH₃; and

(d) a porous separator between said anode and said cathode;

wherein the cathode comprises a lithium-containing manganese composite oxide having a spinel structure as active material, the lithium-containing manganese composite oxide being represented by the formula;

Li_xNi_yM_zMn_2-y-zO_4-d,

 

wherein x is 0.03 to 1.0;

x changes in accordance with release and uptake of lithium ions and electrons during charge and discharge;

y is 0.3 to 0.6;

M comprises one or more of Cr, Fe, Co, Li, Al, Ga, Nb, Mo, Ti, Zr, Mg, Zn, V, and Cu;

z is 0.01 to 0.18, and d is 0 to 0.3.

14. The lithium ion battery of claim 13, wherein y is 0.38 to 0.48, z is 0.03 to 0.12, and d is 0 to 0.1 and wherein M is one or more of Li, Cr, Fe, Co, and Ga.