Non-aqueous electrolyte secondary battery and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-2016197376-A1
Application number	US-201414912839-A
Country	US
Kind code	A1
Filing date	May 21, 2014
Priority date	Sep 5, 2013
Publication date	Jul 7, 2016
Grant date	—

Abstract

A non-aqueous electrolyte secondary battery includes: a positive electrode; a negative electrode that includes an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V or higher (versus Li/Li + ); and a non-aqueous electrolyte solution that contains a lithium salt and a non-aqueous solvent that dissolves the lithium salt therein. The non-aqueous electrolyte solution contains a dinitrile compound and/or a reaction product of the dinitrile compound.

First claim

1 . A non-aqueous electrolyte secondary battery, comprising:
a positive electrode; a negative electrode that includes an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V or higher (versus Li/Li + ); and a non-aqueous electrolyte solution that contains a lithium salt, a non-aqueous solvent, and a dinitrile compound and/or a reaction product of said dinitrile compound.

2 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
a total amount of said dinitrile compound and/or said reaction product of said dinitrile compound in said non-aqueous electrolyte solution is 1 to 5 mass %.

3 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
charge capacity of said non-aqueous electrolyte secondary battery is regulated by said negative electrode.

4 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said lithium salt includes at least lithium hexafluorophosphate and lithium tetrafluoroborate.

5 . The non-aqueous electrolyte secondary battery according to claim 4 , wherein
concentration of said lithium tetrafluoroborate in said non-aqueous electrolyte solution is 0.001 to 0.5 mol/1.

6 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said non-aqueous electrolyte solution contains said dinitrile compound before initial charge.

7 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said dinitrile compound is at least one selected from malononitrile, succinonitrile, glutaronitrile, and adiponitrile.

8 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said titanium oxide is selected from lithium titanate with a spinel structure, lithium titanate with a ramsdellite structure, a monoclinic titanic acid compound, a monoclinic titanium oxide, and lithium hydrogen titanate.

9 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said titanium oxide is selected from Li 4+x Ti 5 O 12 , Li 2+x Ti 3 O 7 , a titanic acid compound given by a general formula H 2 Ti n O 2n+1 , and a bronze titanium oxide (where x is a real number that satisfies 0≦x≦3 and n is an even number of 4 or more).

10 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said titanium oxide has a specific surface area of 5 m 2 /g or more as measured by a single-point BET method using nitrogen adsorption.

11 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
said non-aqueous electrolyte solution contains ethylene carbonate as a solvent and/or at least one selected from vinylene carbonate, ethylene sulfite, and 1,3-propanesultone as an additive.

12 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
an active material of said positive electrode is lithium iron phosphate.

13 . The non-aqueous electrolyte secondary battery according to claim 1 , wherein
an active material of said positive electrode is a lithium manganese composite oxide with a spinel structure.

14 . A method for manufacturing a non-aqueous electrolyte secondary battery, comprising the steps of:
placing in a packaging member a positive electrode, a negative electrode that includes an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V or higher (versus Li/Li + ), and a non-aqueous electrolyte solution that contains at least a lithium salt, a non-aqueous solvent, and a dinitrile compound, and sealing an opening of said packaging member to produce a sealed secondary battery; and charging said sealed secondary battery.

15 . A method for manufacturing a non-aqueous electrolyte secondary battery, comprising the steps of:
placing in a packaging member a positive electrode, a negative electrode that includes an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V or higher (versus Li/Li + ), and a non-aqueous electrolyte solution that contains at least a lithium salt, a non-aqueous solvent, and a dinitrile compound, and temporarily sealing an opening of said packaging member to produce a temporarily sealed secondary battery; adjusting a negative electrode potential of said temporarily sealed secondary battery to a potential higher than 0.8 V and equal to or lower than 1.4 V (versus Li/Li + ) and storing said temporarily sealed secondary battery in an atmosphere of 50° C. or higher and lower than 80° C.; and opening said temporarily sealed secondary battery to discharge gas therefrom, and then finally sealing said packaging member.

16 . The method according to claim 15 , wherein
said storage of said temporarily sealed secondary battery is performed in an open circuit.

17 . The method according to claim 14 , wherein
said non-aqueous electrolyte solution is introduced before said step of charging said sealed secondary battery.

Assignees

• Ishihara Sangyo Kaisha

Inventors

• Koshiba Nobuharu
• Kumashiro Yoshimasa
• Akagawa Kazuhiro

Classifications

• H01M10/0525

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

• H01M10/446

  Initial charging measures · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title