Nonaqueous electrolyte secondary battery and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-9466854-B2
Application number	US-201313934673-A
Country	US
Kind code	B2
Filing date	Jul 3, 2013
Priority date	Jul 4, 2012
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

According to one embodiment, there is provided a nonaqueous electrolyte secondary battery including a positive electrode, a negative electrode containing a titanium-containing oxide, and a nonaqueous electrolyte. The nonaqueous electrolyte contains carbon monoxide and at least one selected from difluorophosphoric acid and monofluorophosphoric acid. The ratio of the mass concentration of carbon monoxide to the sum of the mass concentrations of difluorophosphoric acid and monofluorophosphoric acid is in the range of 0.1 to 5%.

First claim

What is claimed is:

1. A nonaqueous electrolyte secondary battery comprising:
a positive electrode;
a negative electrode containing a titanium-containing oxide; and
a nonaqueous electrolyte,
wherein the nonaqueous electrolyte contains carbon monoxide and at least one selected from difluorophosphoric acid and monofluorophosphoric acid, and
a ratio of a mass concentration of carbon monoxide to a sum of mass concentrations of difluorophosphoric acid and monofluorophosphoric acid is in the range of 0.1 to 5%.

2. The battery according to claim 1 , wherein a ratio of a sum of masses of the difluorophosphoric acid and the monofluorophosphoric acid to a mass of the nonaqueous electrolyte is in the range of 1000 ppm to 50000 ppm.

3. The battery according to claim 1 , wherein a ratio of a mass of carbon monoxide to that of nonaqueous electrolyte is in the range of 5 ppm to 100 ppm.

4. The battery according to claim 2 , wherein a ratio of a mass of carbon monoxide to that of nonaqueous electrolyte is in the range of 5 ppm to 100 ppm.

5. A method for manufacturing a nonaqueous electrolyte secondary battery comprising:
preparing a nonaqueous electrolyte under an inert gas atmosphere excluding carbon dioxide;
dissolving at least one selected from difluorophosphoric acid, monofluorophosphoric acid, and salts thereof in the nonaqueous electrolyte under the inert gas atmosphere;
adjusting a mass concentration of carbon monoxide in the nonaqueous electrolyte to the range of 0.1 to 5% based on a sum of mass concentrations of difluorophosphoric acid and monofluorophosphoric acid under the inert gas atmosphere; and
assembling the nonaqueous electrolyte secondary battery using the nonaqueous electrolyte.

6. The method according to claim 5 , wherein the mass concentration of carbon monoxide is adjusted by bubbling a gas selected from carbon monoxide and an inert gas excluding carbon dioxide in the nonaqueous electrolyte.

Assignees

• Toshiba Kk

Inventors

• Yamamoto Dai
• Matsuno Shinsuke
• Saruwatari Hidesato
• Watando Hiroko
• Morimoto Sayaka
• Kuriyama Kazuya
• Satake Hideki

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• Y02P70/54

  Cross-Sectional Technologies · mapped topic

• H01M10/0568

  characterised by the solutes · CPC title

• H01M10/0525

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