Electrolyte for lithium batteries

• US 8,883,356 B2
• Filed: 06/11/2009
• Issued: 11/11/2014
• Est. Priority Date: 07/30/2008
• Status: Active Grant

• Current Assignee: BYD Company Limited
• Original Assignee: BYD Company Limited
• Inventors: Wang, Yong, Fan, YiWei, Zhou, GuiShu, Si, Lei
• Primary Examiner(s): WEINER, LAURA S
• Application Number:
  US12/482,690
• Publication Number:
  US 20100028771A1
• Time in Patent Office: 1,979 Days
• Field of Search: 429/331, 429/330, 429/200, 429/199, 429/340, 429/329, 429/307, 252/62.2, 296/232
• US Class Current: 429/307
• 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 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 2300/0031 Chlorinated solvents
• CPC Class Codes: H01M 2300/0034 Fluorinated solvents
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/4911 including sealing

Abstract

Electrolyte and lithium secondary batteries containing the same are disclosed. In one instance, the electrolyte includes a lithium salt, a solvent and an additive. In some examples, the additive includes substances A, B and C, wherein substance A is vinylene carbonate, substance B includes at least one of fluorinated or chlorinated ethylene carbonate or diethylene carbonate, and substance C includes at least one of ethylene sulfite, 1,3-propanesultone and propenyl sulfite.

Claims

1. An electrolyte comprising:

a lithium salt;

a solvent; and

an additive, wherein the additive comprises substances A, B and C,

wherein substance A is vinylene carbonate,

wherein substance B has the chemical structure of at least one of

2. The electrolyte of claim 1, wherein the solvent includes at least two members selected from the group consisting essentially of ethylene carbonate, propylene carbonate, diethylene carbonate and γ

-butyrolactone.

3. The electrolyte of claim 1, wherein the amount of additive can be from about 5% to about 40% of the electrolyte by weight.

4. The electrolyte of claim 1, wherein substance B is at least one of fluorinated ethylene carbonate, chloro-substituted ethylene carbonate, fluorinated diethylene carbonate and chloro-substituted diethylene carbonate, and wherein R₂=H, R₃=CH₂, R₄=CH₃ and R₅=C₂H₄Z.

5. The electrolyte of claim 1, substance B is fluorinated ethylene carbonate.

6. The electrolyte of claim 1, wherein the lithium salt includes at least one of lithium perchlorate (LiClO₄), lithium tetrafluoroborate (LiBF₄), lithium bis(oxalato)borate (LiBOB), and lithium hexafluorophosphate (LiPF₆).

7. A lithium battery comprising:

a shell;

a battery core disposed within the shell, wherein the battery core includes an anode, a cathode, and a separator disposed between the anode and the cathode; and

an electrolyte, wherein the electrolyte comprises;

a lithium salt;

a solvent; and

an additive, wherein the additive comprises substances A, B and C,

wherein substance A is vinylene carbonate,

wherein substance B has the chemical structure of at least one of

8. The battery of claim 7, wherein the solvent includes at least two members selected from the group consisting essentially of ethylene carbonate, propylene carbonate, diethylene carbonate and γ

-butyrolactone.

9. The battery of claim 7, wherein the amount of additive can be from about 5% to about 40% of the electrolyte by weight.

10. The battery of claim 7, wherein substance B is at least one of fluorinated ethylene carbonate, chloro-substituted ethylene carbonate, fluorinated diethylene carbonate and chloro-substituted diethylene carbonate, and wherein R₂=H, R₃=CH₂, R₄=CH₃ and R₅=C₂H₄Z.

11. The battery of claim 7, substance B is fluorinated ethylene carbonate.

12. The battery of claim 7, wherein the lithium salt includes at least one of lithium perchlorate (LiClO₄), lithium tetrafluoroborate (LiBF₄), lithium bis(oxalato)borate (LiBOB), and lithium hexafluorophosphate (LiPF₆).

13. A method comprising:

producing an electrolyte for lithium-ion batteries by mixing a lithium salt and an additive to a solvent, wherein the additive comprises substances A, B and C,

wherein substance A is vinylene carbonate,

wherein substance B has the chemical structure of at least one of

14. The method of claim 13, wherein the solvent includes at least two members selected from the group consisting essentially of ethylene carbonate, propylene carbonate, diethylene carbonate and γ

-butyrolactone.

15. The method of claim 13, substance B is fluorinated ethylene carbonate.

16. The method of claim 13, wherein the lithium salt includes at least one of lithium perchlorate (LiClO₄), lithium tetrafluoroborate (LiBF₄), lithium bis(oxalato)borate (LiBOB), and lithium hexafluorophosphate (LiPF₆).

17. A method comprising:

producing a lithium secondary battery by;

situating a separator film between a cathode and an anode to form a battery core;

disposing the battery core within a shell;

injecting an electrolyte within the shell, wherein the electrolyte can be produced using the method of claim 15; and

sealing the electrolyte and the battery core within the shell.