Solvent including 1,2-dialkyl-1,2-difluoroethylene carbonate for non-aqueous electrolytic solution of lithium secondary battery

Patent metadata

Field	Value
Publication number	US-9240616-B2
Application number	US-86492609-A
Country	US
Kind code	B2
Filing date	Jan 22, 2009
Priority date	Jan 29, 2008
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

A solvent for non-aqueous electrolytic solution of lithium secondary battery including a non-fluorine-containing cyclic carbonate (I), a non-fluorine-containing chain carbonate (II) and 1,2-dialkyl-1,2-difluoroethylene carbonate (III). When the total amount of (I), (II) and (III) is taken as 100% by volume, the non-fluorine-containing cyclic carbonate (I) is contained in an amount of 10 to 50% by volume, the non-fluorine-containing chain carbonate (II) is contained in an amount of 49.9 to 89.9% by volume and the 1,2-dialkyl-1,2-difluoroethylene carbonate (III) is contained in an amount of not less than 0.1% by volume and less than 30% by volume. A non-aqueous electrolytic solution including the above-mentioned solvent and a lithium secondary battery using the non-aqueous electrolytic solution are also disclosed.

First claim

The invention claimed is:

1. A solvent for non-aqueous electrolytic solution of lithium secondary battery comprising
a non-fluorine-containing cyclic carbonate (I),
a non-fluorine-containing chain carbonate (II) and 1,2-dialkyl-1,2-difluoroethylene carbonate (III),
wherein the non-fluorine-containing cyclic carbonate (I) is at least one selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate and vinylene carbonate,
wherein the non-fluorine-containing chain carbonate (II) is at least one selected from the group consisting of diethyl carbonate, methyl ethyl carbonate, dimethyl carbonate and methyl propyl carbonate;
wherein the 1,2-dialkyl-1,2-difluoroethylene carbonate (III) is at least one selected from the group consisting of 1,2-dimethyl-1,2-difluoroethylene carbonate, 1,2-diethyl-1,2-difluoroethylene carbonate and 1-methyl-2-ethyl-1,2-difluoroethylene carbonate, and
wherein when the total amount of (I), (II) and (III) is taken as 100% by volume,
the non-fluorine-containing cyclic carbonate (I) is contained in an amount of 10 to 50% by volume,
the non-fluorine-containing chain carbonate (II) is contained in an amount of 49.5 to 89.5% by volume, and
the 1,2-dialkyl-1,2-difluoroethylene carbonate (III) is contained in an amount of not less than 0.5% by volume and less than 30% by volume.

2. The solvent for non-aqueous electrolytic solution of claim 1 , wherein the non-fluorine-containing cyclic carbonate (I) is one of ethylene carbonate and propylene carbonate or a mixture thereof.

3. The solvent for non-aqueous electrolytic solution of claim 1 , wherein the non-fluorine-containing chain carbonate (II) is one of dimethyl carbonate, methyl ethyl carbonate and diethyl carbonate or a mixture thereof.

4. The solvent for non-aqueous electrolytic solution of claim 1 , wherein when the total amount of (I), (II) and (III) is taken as 100% by volume,
the non-fluorine-containing cyclic carbonate (I) is contained in an amount of 10 to 40% by volume,
the non-fluorine-containing chain carbonate (II) is contained in an amount of 59.5 to 89.5% by volume, and
the 1,2-dialkyl-1,2-difluoroethylene carbonate (III) is contained in an amount of not less than 0.5% by volume and less than 10% by volume.

5. The solvent for non-aqueous electrolytic solution of claim 1 , wherein the 1,2-dialkyl-1,2-difluoroethylene carbonate (III) is 1,2-dimethyl-1,2-difluoroethylene carbonate.

6. The solvent for non-aqueous electrolytic solution of claim 5 , wherein the 1,2-dimethyl-1,2-difluoroethylene carbonate (III) is cis-form.

7. The solvent for non-aqueous electrolytic solution of claim 5 , wherein the 1,2-dimethyl-1,2-difluoroethylene carbonate (III) is trans-form.

8. A non-aqueous electrolytic solution of lithium secondary battery comprising the solvent for non-aqueous electrolytic solution of claim 1 , and
an electrolyte salt.

9. A lithium secondary battery using the non-aqueous electrolytic solution of claim 8 .

Assignees

• Koh Meiten
• Sakata Hideo
• Nakazawa Hitomi
• Yamauchi Akiyoshi
• Tani Akinori
• Daikin Ind Ltd

Inventors

• Koh Meiten
• Sakata Hideo
• Nakazawa Hitomi
• Yamauchi Akiyoshi
• Tani Akinori

Classifications

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• Y02T10/7011

  Cross-Sectional Technologies · mapped topic

• Y02E60/10

  Energy storage using batteries · CPC title