Non-aqueous electrolyte secondary battery and production method thereof

Patent metadata

Field	Value
Publication number	US-9923192-B2
Application number	US-201313968965-A
Country	US
Kind code	B2
Filing date	Aug 16, 2013
Priority date	Feb 18, 2011
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

According to one embodiment, there is provided a non-aqueous electrolyte secondary battery including a positive electrode, a negative electrode including a negative electrode active material layer, and a non-aqueous electrolyte. The negative electrode active material layer contains carbon dioxide and releases the carbon dioxide in the range of 0.1 ml to 5 ml per 1 g when heated at 200° C. for 1 minute.

First claim

What is claimed is:

1. A non-aqueous electrolyte secondary battery, comprising:
a positive electrode;
a negative electrode comprising a negative electrode active material layer; and
a non-aqueous electrolyte;
wherein:
the negative electrode active material layer contains physically adsorbed carbon dioxide in the range of 0.1 ml to 5 ml per 1 g of the negative electrode active material layer;
the negative electrode active material layer further contains lithium carbonate; and
the physically adsorbed carbon dioxide and the lithium carbonate contained in the negative electrode active material layer exist in such a form that in pyrolysis-gas chromatography/mass spectrometry for the negative electrode active material layer under a temperature rising condition of 5° C./minute, two peaks appear in the range of 120° C. to 350° C., where a ratio (a/b) of an intensity a of a low temperature side peak of the two peaks to an intensity b of a high temperature side peak of the two peaks is 1 or more.

2. The non-aqueous electrolyte secondary battery according to claim 1 ,
wherein the negative electrode active material layer contains the physically adsorbed carbon dioxide in the range of 0.2 ml to 2 ml per 1 g of the negative electrode active material layer.

3. The non-aqueous electrolyte secondary battery according to claim 1 ,
wherein the negative electrode active material layer further contains a lithium titanium composite oxide.

4. The non-aqueous electrolyte secondary battery according to claim 2 ,
wherein the negative electrode active material layer further contains a lithium titanium composite oxide.

5. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode active material layer releases carbon dioxide in the range of 0.1 ml to 5 ml per 1 g of the negative electrode active material layer, as measured by gas chromatography, when the negative electrode is washed with methyl ethyl carbonate and dried under a reduced pressure atmosphere, then the negative electrode active material layer is scraped out from the negative electrode, and the negative electrode active material layer is heated at 200° C. for 1 minute and the heated negative electrode active material is analyzed by gas chromatography.

6. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the non-aqueous electrolyte contains carbon dioxide and the carbon dioxide in the non-aqueous electrolyte functions as a shuttle compound that shuttles between the positive electrode and the negative electrode.

7. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the positive electrode active material comprises at least one member selected from the group consisting of lithium manganese composite oxide, lithium nickel composite oxide and lithium-containing phosphate compound.

8. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode active material has a lithium ion absorption potential of 0.4 V or more (versus Li/Li + ).

9. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode active material has an average primary particle diameter of 5 μm or less and a specific surface area of 1 to 10 m 2 /g.

10. The non-aqueous electrolyte secondary battery according to claim 1 , wherein a solid electrolyte interface film is formed on the surface of the negative electrode and the film has a thickness of 10 nm or less.

11. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode active material releases carbon dioxide in the range of 0.1 ml to 5 ml per 1 g of the negative electrode active material layer, as measured by gas chromatography by a process comprising:
washing the negative electrode with methyl ethyl carbonate for 10 minutes;
drying the washed negative electrode under a reduced pressure atmosphere of −80 kPa for one hour at room temperature without atmospheric exposure;
removing a sample of the negative electrode active material from the dried negative electrode in an inert gas atmosphere;
heating a sample of the negative electrode active material at 200° C. for 1 minute under an inert gas atmosphere; and
analyzing the heated sample of the negative electrode active material by gas chromatography,
wherein the inert gas is an inert gas other than carbon dioxide.

12. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode active material is prepared in an inert gas atmosphere having a dew point of −10° C. or less.

Assignees

• Toshiba Kk
• Kabushiki Kaihsa Toshiba

Inventors

• Matsuno Shinsuke
• Saruwatari Hidesato
• Yamamoto Dai
• Kondo Asato
• Kuriyama Hiromichi
• Satake Hideki
• Kuboki Takashi

Classifications

• H01M10/052

  Li-accumulators · CPC title

• Y10T29/49108

  Electric battery cell making · CPC title

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/133 Primary

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title